Use IDO for assembling handwritten asm files in src (#2390)

* as0 * Fix ASOPTFLAGS for src/libc, remove unnecessary noreorder region in kanread * Suggested changes * Use %half to load the boot bss size for matching Co-authored-by: cadmic <cadmic24@gmail.com> * Wrap all of __osProbeTLB in noreorder --------- Co-authored-by: cadmic <cadmic24@gmail.com>
author: Tharo <17233964+Thar0@users.noreply.github.com> 2024-12-28 20:18:45 +0000
committer: GitHub <noreply@github.com> 2024-12-28 15:18:45 -0500
commit: 7e082f0c4f6b34820b4dbf6285d05adf423c091b (patch)
tree: 5b2f1d322eafd4afd6b30109eab12ae36d2b72bf /src
parent: ba6a83533ac3dcbd6c0c70c9857572ed1ef1d009 (diff)
46 files changed, 1868 insertions, 2165 deletions
diff --git a/src/boot/mio0.s b/src/boot/mio0.s
index a3fb8eba2..a6c2eee6b 100644
--- a/src/boot/mio0.s
+++ b/src/boot/mio0.s
@@ -1,10 +1,7 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  *  void Mio0_Decompress(void* src, void* dst);
@@ -12,53 +9,56 @@
  *  Decompress Mio0 chunk
  */
 LEAF(Mio0_Decompress)
-    lw      $a3, 8($a0)     // compressed offset
-    lw      $t9, 0xC($a0)   // uncompressed offset
-    lw      $t8, 4($a0)     // decompressed length
-    add     $a3, $a3, $a0   // compressed start
-    add     $t9, $t9, $a0   // uncompressed start
-    move    $a2, $zero      // 0
-    addi    $a0, $a0, 0x10  // move past header
-    add     $t8, $t8, $a1   // dst + decompressed length = end
+    lw      a3, 0x08(a0)    /* compressed offset */
+    lw      t9, 0x0C(a0)    /* uncompressed offset */
+    lw      t8, 0x04(a0)    /* decompressed length */
+    add     a3, a3, a0      /* compressed start */
+    add     t9, t9, a0      /* uncompressed start */
+    move    a2, zero        /* 0 */
+    addi    a0, a0, 0x10    /* move past header */
+    add     t8, t8, a1      /* dst + decompressed length = end */
 mainloop:
-    bnez    $a2, 1f
-     nop
-    lw      $t0, ($a0)
-    li      $a2, 32
-    addi    $a0, $a0, 4
+    bnez    a2, 1f
+
+    lw      t0, (a0)
+    li      a2, 32
+    addi    a0, a0, 4
 1:
-    slt     $t1, $t0, $zero
-    beqz    $t1, read_comp
-     nop
-    lb      $t2, ($t9)      // read 1 byte from uncompressed data
-    addi    $t9, $t9, 1     // advance uncompressed start
-    addi    $a1, $a1, 1
+    slt     t1, t0, zero
+    beqz    t1, read_comp
+
+    lb      t2, (t9)      /* read 1 byte from uncompressed data */
+    sb      t2, (a1)      /* store uncompressed byte */
+    addi    t9, t9, 1     /* advance uncompressed start */
+    addi    a1, a1, 1
     b       next_iter
-     sb     $t2, -1($a1)    // store uncompressed byte
+
 read_comp:
-    lhu     $t2, ($a3)      // read 2 bytes from compressed data
-    addi    $a3, $a3, 2     // advance compressed start
-    srl     $t3, $t2, 0xC
-    andi    $t2, $t2, 0xFFF
-    beqz    $t3, 3f
-     sub    $t1, $a1, $t2
-    addi    $t3, $t3, 2
+    lhu     t2, (a3)      /* read 2 bytes from compressed data */
+    addi    a3, a3, 2     /* advance compressed start */
+    srl     t3, t2, 0xC
+    andi    t2, t2, 0xFFF
+    sub     t1, a1, t2
+    beqz    t3, 3f
+
+    addi    t3, t3, 2
 2:
-    lb      $t2, -1($t1)
-    addi    $t3, $t3, -1
-    addi    $t1, $t1, 1
-    addi    $a1, $a1, 1
-    bnez    $t3, 2b
-     sb     $t2, -1($a1)
+    lb      t2, -1(t1)
+    addi    t3, t3, -1
+    addi    t1, t1, 1
+    sb      t2, (a1)
+    addi    a1, a1, 1
+    bnez    t3, 2b
+
 next_iter:
-    sll     $t0, $t0, 1
-    bne     $a1, $t8, mainloop // continue until decompressed length is reached
-     addi   $a2, $a2, -1
-    jr      $ra
-     nop
+    sll     t0, t0, 1
+    addi    a2, a2, -1
+    bne     a1, t8, mainloop /* continue until decompressed length is reached */
+
+    jr      ra
 3:
-    lbu     $t3, ($t9)
-    addi    $t9, $t9, 1
+    lbu     t3, (t9)
+    addi    t9, t9, 1
+    addi    t3, t3, 0x12
     b       2b
-     addi   $t3, $t3, 0x12
 END(Mio0_Decompress)
diff --git a/src/code/kanread.s b/src/code/kanread.s
index a163f9ead..fdf69ed9b 100644
--- a/src/code/kanread.s
+++ b/src/code/kanread.s
@@ -1,11 +1,7 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  * s32 Kanji_OffsetFromShiftJIS(s32 sjis);
@@ -26,64 +22,57 @@
  * @remark Almost identical to "LeoGetKadr" from libleo.
  */
 LEAF(Kanji_OffsetFromShiftJIS)
-    // Characters with codepoints >= 0x8800 are kanji. Arrangement is regular,
-    // so convert index directly.
-    li      $at, 0x8800
-    slt     $at, $a0, $at
-    bnez    $at, .nonkanji
-     // 0xBC is number of glyphs in one block in the `kanji` file:
-     // 0x100 possible codepoints with the same byte1
-     // - 0x40 unused at beginning
-     // - 1 unused at 0x7F
-     // - 3 unused at 0xFD, 0xFE, 0xFF
-     li     $a2, 0xBC
-    // Get byte1 and adjust so starts at 0
-    srl     $a1, $a0, 8
-    addi    $a1, $a1, -0x88
-    multu   $a2, $a1
-    // Get byte2 and adjust so starts at 0
-    andi    $a3, $a0, 0xFF
-    addi    $a3, $a3, -0x40
-    slti    $at, $a3, (0x80 - 0x40)
-    mflo    $a2
-    // 0x__7F is always empty and elided in the file, so decrement if larger
-    bnezl   $at, .kanji_lower_halfblock
-     mflo   $a2
-    addi    $a3, $a3, -1
-    mflo    $a2
+    /* Characters with codepoints >= 0x8800 are kanji. Arrangement is regular, */
+    /* so convert index directly. */
+    li      a2, 0xBC
+    blt     a0, 0x8800, .nonkanji
+     /* 0xBC is number of glyphs in one block in the `kanji` file: */
+     /* 0x100 possible codepoints with the same byte1 */
+     /* - 0x40 unused at beginning */
+     /* - 1 unused at 0x7F */
+     /* - 3 unused at 0xFD, 0xFE, 0xFF */
+    /* Get byte1 and adjust so starts at 0 */
+    srl     a1, a0, 8
+    addi    a1, a1, -0x88
+    /* Get byte2 and adjust so starts at 0 */
+    andi    a3, a0, 0xFF
+    addi    a3, a3, -0x40
+    mul     a2, a2, a1
+    blt     a3, 0x40, .kanji_lower_halfblock
+
+    /* 0x__7F is always empty and elided in the file, so decrement if larger */
+    addi    a3, a3, -1
 .kanji_lower_halfblock:
-    addi    $a3, $a3, 0x30A
-    add     $a3, $a3, $a2
-    jr      $ra
-     sll    $v0, $a3, 7
-     // returns (0x30A + (adjusted byte2) + (adjusted byte1) * 0xBC) * FONT_CHAR_TEX_SIZE
+    mflo    a2  /* Unncessary mflo: the pseudo-op `mul` already performs mflo */
+    addi    a3, a3, 0x30A
+    add     a3, a3, a2
+    /* returns (0x30A + (adjusted byte2) + (adjusted byte1) * 0xBC) * FONT_CHAR_TEX_SIZE */
+    sll     v0, a3, 7
+    jr      ra
 
-// Non-kanji are arranged with irregular gaps, use the lookup table.
+/* Non-kanji are arranged with irregular gaps, use the lookup table. */
 .nonkanji:
-    // Get byte1 and adjust so starts at 0
-    srl     $a1, $a0, 8
-    addi    $a1, $a1, -0x81
-    multu   $a2, $a1
-    // Get byte2 and adjust so starts at 0
-    andi    $a3, $a0, 0xFF
-    addi    $a3, $a3, -0x40
-    slti    $at, $a3, (0x80 - 0x40)
-    mflo    $a2
-    // 0x__7F is always empty and elided in the file, so decrement if larger
-    bnezl   $at, .nonkanji_lower_halfblock
-     mflo   $a2
-    addi    $a3, $a3, -1
-    mflo    $a2
+    /* Get byte1 and adjust so starts at 0 */
+    srl     a1, a0, 8
+    addi    a1, a1, -0x81
+    /* Get byte2 and adjust so starts at 0 */
+    andi    a3, a0, 0xFF
+    addi    a3, a3, -0x40
+    mul     a2, a2, a1
+    blt     a3, 0x40, .nonkanji_lower_halfblock
+
+    /* 0x__7F is always empty and elided in the file, so decrement if larger */
+    addi    a3, a3, -1
 .nonkanji_lower_halfblock:
-    add     $a3, $a3, $a2
-    lui     $a2, %hi(sNonKanjiIndices)
-    sll     $a3, $a3, 1
-    addiu   $a2, %lo(sNonKanjiIndices)
-    add     $a3, $a3, $a2
-    lh      $a2, ($a3)
-    jr      $ra
-     sll    $v0, $a2, 7
-     // returns sNonKanjiIndices[(adjusted byte2) + (adjusted byte1) * 0xBC] * FONT_CHAR_TEX_SIZE
+    mflo    a2  /* Unncessary mflo: the pseudo-op `mul` already performs mflo */
+    add     a3, a3, a2
+    sll     a3, a3, 1
+    la      a2, sNonKanjiIndices
+    add     a3, a3, a2
+    lh      a2, (a3)
+    /* returns sNonKanjiIndices[(adjusted byte2) + (adjusted byte1) * 0xBC] * FONT_CHAR_TEX_SIZE */
+    sll     v0, a2, 7
+    jr      ra
 END(Kanji_OffsetFromShiftJIS)
 
 /**
@@ -116,7 +105,7 @@ END(Kanji_OffsetFromShiftJIS)
  * into blocks by high byte.
  */
 DATA(sNonKanjiIndices)
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x814_ */ .half 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000A, 0x000B, 0x000C, 0x000D, 0x000E, 0x000F
 /* 0x815_ */ .half 0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001A, 0x001B, 0x001C, 0x001D, 0x001E, 0x001F
 /* 0x816_ */ .half 0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002A, 0x002B, 0x002C, 0x002D, 0x002E, 0x002F
@@ -130,7 +119,7 @@ DATA(sNonKanjiIndices)
 /* 0x81E_ */ .half 0x0080, 0x0081, 0x0082, 0x0083, 0x0084, 0x0085, 0x0086, 0x0087, 0x0088, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x81F_ */ .half 0x0089, 0x008A, 0x008B, 0x008C, 0x008D, 0x008E, 0x008F, 0x0090, 0x0000, 0x0000, 0x0000, 0x0000, 0x0091
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x824_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0092
 /* 0x825_ */ .half 0x0093, 0x0094, 0x0095, 0x0096, 0x0097, 0x0098, 0x0099, 0x009A, 0x009B, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x826_ */ .half 0x009C, 0x009D, 0x009E, 0x009F, 0x00A0, 0x00A1, 0x00A2, 0x00A3, 0x00A4, 0x00A5, 0x00A6, 0x00A7, 0x00A8, 0x00A9, 0x00AA, 0x00AB
@@ -144,7 +133,7 @@ DATA(sNonKanjiIndices)
 /* 0x82E_ */ .half 0x0111, 0x0112, 0x0113, 0x0114, 0x0115, 0x0116, 0x0117, 0x0118, 0x0119, 0x011A, 0x011B, 0x011C, 0x011D, 0x011E, 0x011F, 0x0120
 /* 0x82F_ */ .half 0x0121, 0x0122, 0x0123, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x834_ */ .half 0x0124, 0x0125, 0x0126, 0x0127, 0x0128, 0x0129, 0x012A, 0x012B, 0x012C, 0x012D, 0x012E, 0x012F, 0x0130, 0x0131, 0x0132, 0x0133
 /* 0x835_ */ .half 0x0134, 0x0135, 0x0136, 0x0137, 0x0138, 0x0139, 0x013A, 0x013B, 0x013C, 0x013D, 0x013E, 0x013F, 0x0140, 0x0141, 0x0142, 0x0143
 /* 0x836_ */ .half 0x0144, 0x0145, 0x0146, 0x0147, 0x0148, 0x0149, 0x014A, 0x014B, 0x014C, 0x014D, 0x014E, 0x014F, 0x0150, 0x0151, 0x0152, 0x0153
@@ -158,7 +147,7 @@ DATA(sNonKanjiIndices)
 /* 0x83E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x83F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x844_ */ .half 0x01AB, 0x01AC, 0x01AD, 0x01AE, 0x01AF, 0x01B0, 0x01B1, 0x01B2, 0x01B3, 0x01B4, 0x01B5, 0x01B6, 0x01B7, 0x01B8, 0x01B9, 0x01BA
 /* 0x845_ */ .half 0x01BB, 0x01BC, 0x01BD, 0x01BE, 0x01BF, 0x01C0, 0x01C1, 0x01C2, 0x01C3, 0x01C4, 0x01C5, 0x01C6, 0x01C7, 0x01C8, 0x01C9, 0x01CA
 /* 0x846_ */ .half 0x01CB, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
@@ -172,7 +161,7 @@ DATA(sNonKanjiIndices)
 /* 0x84E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x84F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x854_ */ .half 0x020E, 0x020F, 0x0210, 0x0211, 0x0212, 0x0213, 0x0214, 0x0215, 0x0216, 0x0217, 0x0218, 0x0219, 0x021A, 0x021B, 0x021C, 0x021D
 /* 0x855_ */ .half 0x021E, 0x021F, 0x0220, 0x0221, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0222, 0x0223
 /* 0x856_ */ .half 0x0224, 0x0225, 0x0226, 0x0227, 0x0228, 0x0229, 0x022A, 0x022B, 0x022C, 0x022D, 0x022E, 0x022F, 0x0230, 0x0231, 0x0232, 0x0233
@@ -186,7 +175,7 @@ DATA(sNonKanjiIndices)
 /* 0x85E_ */ .half 0x026C, 0x026D, 0x026E, 0x026F, 0x0270, 0x0271, 0x0272, 0x0273, 0x0274, 0x0275, 0x0276, 0x0277, 0x0278, 0x0279, 0x027A, 0x027B
 /* 0x85F_ */ .half 0x027C, 0x027D, 0x027E, 0x027F, 0x0280, 0x0281, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x864_ */ .half 0x0282, 0x0283, 0x0284, 0x0285, 0x0286, 0x0287, 0x0288, 0x0289, 0x028A, 0x028B, 0x028C, 0x028D, 0x028E, 0x028F, 0x0290, 0x0291
 /* 0x865_ */ .half 0x0292, 0x0293, 0x0294, 0x0295, 0x0296, 0x0297, 0x0298, 0x0299, 0x029A, 0x029B, 0x029C, 0x029D, 0x029E, 0x029F, 0x0000, 0x0000
 /* 0x866_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
@@ -200,7 +189,7 @@ DATA(sNonKanjiIndices)
 /* 0x86E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x86F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x874_ */ .half 0x02C0, 0x02C1, 0x02C2, 0x02C3, 0x02C4, 0x02C5, 0x02C6, 0x02C7, 0x02C8, 0x02C9, 0x02CA, 0x02CB, 0x02CC, 0x02CD, 0x02CE, 0x02CF
 /* 0x875_ */ .half 0x02D0, 0x02D1, 0x02D2, 0x02D3, 0x02D4, 0x02D5, 0x02D6, 0x02D7, 0x02D8, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x876_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
diff --git a/src/code/z_vimode.c b/src/code/z_vimode.c
index 59fa5df2d..0d2f5716f 100644
--- a/src/code/z_vimode.c
+++ b/src/code/z_vimode.c
@@ -86,7 +86,7 @@ void ViMode_Configure(ViMode* viMode, s32 type, s32 tvType, s32 loRes, s32 antia
     yScaleHiOddField = modeF ? (loResInterlaced ? (F210(0.75) << 16) : (F210(0.5) << 16)) : 0;
 
     viMode->customViMode.type = type;
-    viMode->customViMode.comRegs.ctrl = VI_CTRL_PIXEL_ADV_3 | VI_CTRL_GAMMA_ON | VI_CTRL_GAMMA_DITHER_ON |
+    viMode->customViMode.comRegs.ctrl = VI_CTRL_PIXEL_ADV(3) | VI_CTRL_GAMMA_ON | VI_CTRL_GAMMA_DITHER_ON |
                                         (!loResDeinterlaced ? VI_CTRL_SERRATE_ON : 0) |
                                         (antialiasOn ? VI_CTRL_DIVOT_ON : 0) |
                                         (fb32Bit ? VI_CTRL_TYPE_32 : VI_CTRL_TYPE_16);
diff --git a/src/libc/absf.s b/src/libc/absf.s
index b42333461..58450e779 100644
--- a/src/libc/absf.s
+++ b/src/libc/absf.s
@@ -1,15 +1,9 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-#if DEBUG_FEATURES
-.set noreorder
-#endif
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(absf)
-    abs.s       $f0, $f12
-    jr          $ra
-     nop
+    abs.s       fv0, fa0
+    jr          ra
 END(absf)
diff --git a/src/libc/sqrt.s b/src/libc/sqrt.s
index 6ffb2b708..1d69d3adb 100644
--- a/src/libc/sqrt.s
+++ b/src/libc/sqrt.s
@@ -1,15 +1,9 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-#if DEBUG_FEATURES
-.set noreorder
-#endif
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(sqrt)
-    sqrt.d      $f0, $f12
-    jr          $ra
-     nop
+    sqrt.d      fv0, fa0
+    jr          ra
 END(sqrt)
diff --git a/src/libc64/fp.s b/src/libc64/fp.s
index 117e7815e..32c084ef5 100644
--- a/src/libc64/fp.s
+++ b/src/libc64/fp.s
@@ -1,12 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noreorder
-
-.section .data
-
-.balign 16
+.data
 
 #if !PLATFORM_N64
+
 DATA(gPositiveInfinity)
     .word 0x7F800000
 ENDDATA(gPositiveInfinity)
@@ -34,150 +32,135 @@ ENDDATA(qNaN0x10000)
 DATA(sNaN0x3FFFFF)
     .word 0x7FFFFFFF
 ENDDATA(sNaN0x3FFFFF)
-#endif
 
-.section .text
+#endif
 
-.balign 16
+.text
 
 LEAF(floorf)
-    floor.w.s   $f12, $f12
-    jr          $ra
-     cvt.s.w    $f0, $f12
+    floor.w.s   fa0, fa0
+    cvt.s.w     fv0, fa0
+    jr          ra
 END(floorf)
 
 LEAF(floor)
-    floor.w.d   $f12, $f12
-    jr          $ra
-     cvt.d.w    $f0, $f12
+    floor.w.d   fa0, fa0
+    cvt.d.w     fv0, fa0
+    jr          ra
 END(floor)
 
 LEAF(lfloorf)
-    floor.w.s   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    floor.w.s   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lfloorf)
 
 LEAF(lfloor)
-    floor.w.d   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    floor.w.d   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lfloor)
 
 LEAF(ceilf)
-    ceil.w.s    $f12, $f12
-    jr          $ra
-     cvt.s.w    $f0, $f12
+    ceil.w.s    fa0, fa0
+    cvt.s.w     fv0, fa0
+    jr          ra
 END(ceilf)
 
 LEAF(ceil)
-    ceil.w.d    $f12, $f12
-    jr          $ra
-     cvt.d.w    $f0, $f12
+    ceil.w.d    fa0, fa0
+    cvt.d.w     fv0, fa0
+    jr          ra
 END(ceil)
 
 LEAF(lceilf)
-    ceil.w.s    $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    ceil.w.s    ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lceilf)
 
 LEAF(lceil)
-    ceil.w.d    $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    ceil.w.d    ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lceil)
 
 LEAF(truncf)
-    trunc.w.s   $f12, $f12
-    jr          $ra
-     cvt.s.w    $f0, $f12
+    trunc.w.s   fa0, fa0
+    cvt.s.w     fv0, fa0
+    jr          ra
 END(truncf)
 
 LEAF(trunc)
-    trunc.w.d   $f12, $f12
-    jr          $ra
-     cvt.d.w    $f0, $f12
+    trunc.w.d   fa0, fa0
+    cvt.d.w     fv0, fa0
+    jr          ra
 END(trunc)
 
 LEAF(ltruncf)
-    trunc.w.s   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    trunc.w.s   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(ltruncf)
 
 LEAF(ltrunc)
-    trunc.w.d   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    trunc.w.d   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(ltrunc)
 
 LEAF(nearbyintf)
-    round.w.s   $f12, $f12
-    jr          $ra
-     cvt.s.w    $f0, $f12
+    round.w.s   fa0, fa0
+    cvt.s.w     fv0, fa0
+    jr          ra
 END(nearbyintf)
 
 LEAF(nearbyint)
-    round.w.d   $f12, $f12
-    jr          $ra
-     cvt.d.w    $f0, $f12
+    round.w.d   fa0, fa0
+    cvt.d.w     fv0, fa0
+    jr          ra
 END(nearbyint)
 
 LEAF(lnearbyintf)
-    round.w.s   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    round.w.s   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lnearbyintf)
 
 LEAF(lnearbyint)
-    round.w.d   $f4, $f12
-    mfc1        $v0, $f4
-    jr          $ra
-     nop
+    round.w.d   ft0, fa0
+    mfc1        v0, ft0
+    jr          ra
 END(lnearbyint)
 
 LEAF(roundf)
-    li.s        $f4, 0.5
-    nop
-    add.s       $f0, $f12, $f4
-    floor.w.s   $f0, $f0
-    jr          $ra
-     cvt.s.w     $f0, $f0
+    li.s        ft0, 0.5
+    add.s       fv0, fa0, ft0
+    floor.w.s   fv0, fv0
+    cvt.s.w     fv0, fv0
+    jr          ra
 END(roundf)
 
 LEAF(round)
-    li.d        $f4, 0.5
-    nop
-    add.d       $f0, $f12, $f4
-    floor.w.d   $f0, $f0
-    jr          $ra
-     cvt.d.w     $f0, $f0
+    li.d        ft0, 0.5
+    add.d       fv0, fa0, ft0
+    floor.w.d   fv0, fv0
+    cvt.d.w     fv0, fv0
+    jr          ra
 END(round)
 
 LEAF(lroundf)
-    li.s        $f4, 0.5
-    nop
-    add.s       $f0, $f12, $f4
-    floor.w.s   $f0, $f0
-    mfc1        $v0, $f0
-    jr          $ra
-     nop
+    li.s        ft0, 0.5
+    add.s       fv0, fa0, ft0
+    floor.w.s   fv0, fv0
+    mfc1        v0, fv0
+    jr          ra
 END(lroundf)
 
 LEAF(lround)
-    li.d        $f4, 0.5
-    nop
-    add.d       $f0, $f12, $f4
-    floor.w.d   $f0, $f0
-    mfc1        $v0, $f0
-    jr          $ra
-     nop
+    li.d        ft0, 0.5
+    add.d       fv0, fa0, ft0
+    floor.w.d   fv0, fv0
+    mfc1        v0, fv0
+    jr          ra
 END(lround)
diff --git a/src/libleo/api/getaadr.s b/src/libleo/api/getaadr.s
index a36d27a5b..95c1cfb14 100644
--- a/src/libleo/api/getaadr.s
+++ b/src/libleo/api/getaadr.s
@@ -1,42 +1,33 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(LeoGetAAdr)
-    bltz    $a0, .out_of_range
-     slti   $at, $a0, 0x908
-    beqz    $at, .out_of_range
-     nop
-    lui     $v1, %hi(asc2tbl)
-    sll     $t0, $a0, 2
-    addiu   $v1, %lo(asc2tbl)
-    add     $t1, $t0, $v1
-    lbu     $t8, 2($t1)
-    lhu     $t9, 0($t1)
-    li      $at, 0x70000
-    andi    $t2, $t8, 0xF
-    addi    $t3, $t2, 1
-    sw      $t3, ($a2)
-    lb      $t0, 3($t1)
-    srl     $t4, $t8, 4
-    ori     $at, $at, 0xEE80
-    andi    $t5, $t0, 1
-    sll     $t6, $t5, 4
-    or      $t7, $t6, $t4
-    sw      $t7, ($a1)
-    sll     $v0, $t9, 1
-    sra     $v1, $t0, 1
-    sw      $v1, ($a3)
-    jr      $ra
-     add     $v0, $v0, $at
+    bltz    a0, .out_of_range
+    bge     a0, 0x908, .out_of_range
+    sll     t0, a0, 2
+    la      v1, asc2tbl
+    add     t1, t0, v1
+    lbu     t8, 2(t1)
+    lhu     t9, 0(t1)
+    andi    t2, t8, 0xF
+    addi    t3, t2, 1
+    sw      t3, (a2)
+    lb      t0, 3(t1)
+    srl     t4, t8, 4
+    andi    t5, t0, 1
+    sll     t6, t5, 4
+    or      t7, t6, t4
+    sw      t7, (a1)
+    sll     v0, t9, 1
+    sra     v1, t0, 1
+    sw      v1, (a3)
+    add     v0, v0, 0x7EE80
+    jr      ra
 .out_of_range:
-    jr      $ra
-     li     $v0, -1
+    li      v0, -1
+    jr      ra
 END(LeoGetAAdr)
 
 DATA(asc2tbl)
diff --git a/src/libleo/api/getaadr2.s b/src/libleo/api/getaadr2.s
index e3ea0868b..cac52cd90 100644
--- a/src/libleo/api/getaadr2.s
+++ b/src/libleo/api/getaadr2.s
@@ -1,33 +1,25 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(LeoGetAAdr2)
-    li      $at, 0x10000
-    srl     $t8, $a0, 0xF
-    ori     $at, $at, 0xFFFE
-    and     $v1, $t8, $at
-    li      $at, 0x70000
-    ori     $at, $at, 0xEE80
-    srl     $t2, $a0, 0x8
-    add     $v0, $v1, $at
-    andi    $t3, $t2, 0xF
-    andi    $t5, $a0, 0xFE
-    addi    $t4, $t3, 1
-    sll     $t6, $t5, 0x18
-    andi    $t9, $a0, 0x1
-    srl     $v1, $a0, 0xC
-    sw      $t4, ($a2)
-    sra     $t7, $t6, 0x19
-    sll     $t8, $t9, 0x4
-    andi    $t1, $v1, 0xF
-    sw      $t7, ($a3)
-    or      $t2, $t1, $t8
-    jr      $ra
-     sw     $t2, ($a1)
+    srl     t8, a0, 15
+    and     v1, t8, 0x1FFFE
+    add     v0, v1, 0x7EE80
+    srl     t2, a0, 8
+    andi    t3, t2, 0xF
+    andi    t5, a0, 0xFE
+    addi    t4, t3, 1
+    sll     t6, t5, 24
+    andi    t9, a0, 1
+    srl     v1, a0, 12
+    sw      t4, (a2)
+    sra     t7, t6, 25
+    sll     t8, t9, 4
+    andi    t1, v1, 0xF
+    sw      t7, (a3)
+    or      t2, t1, t8
+    sw      t2, (a1)
+    jr      ra
 END(LeoGetAAdr2)
diff --git a/src/libleo/api/getkadr.s b/src/libleo/api/getkadr.s
index 22d85cb59..d71719525 100644
--- a/src/libleo/api/getkadr.s
+++ b/src/libleo/api/getkadr.s
@@ -1,11 +1,7 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  * int LeoGetKAdr(int sjis);
@@ -22,74 +18,61 @@
  * @return int Storage offset address into the N64 Disk Drive mask ROM.
  */
 LEAF(LeoGetKAdr)
-    // Check if the codepoint is in the range 0x8140 to 0x9872.
-    li      $at, 0x8140
-    slt     $at, $a0, $at
-    bnez    $at, .out_of_range
-    li      $at, 0x9873
-    slt     $at, $a0, $at
-    beqz    $at, .out_of_range
-    // Characters with codepoints >= 0x8800 are kanji. Arrangement is regular,
-    // so convert index directly.
-    li      $at, 0x8800
-    slt     $at, $a0, $at
-    bnez    $at, .nonkanji
-     // 0xBC is number of glyphs in one block in the `kanji` file:
-     // 0x100 possible codepoints with the same byte1
-     // - 0x40 unused at beginning
-     // - 1 unused at 0x7F
-     // - 3 unused at 0xFD, 0xFE, 0xFF
-     li     $a2, 0xBC
-    // Get byte1 and adjust so starts at 0
-    srl     $a1, $a0, 8
-    addi    $a1, $a1, -0x88
-    multu   $a2, $a1
-    // Get byte2 and adjust so starts at 0
-    andi    $a3, $a0, 0xFF
-    addi    $a3, $a3, -0x40
-    slti    $at, $a3, (0x80 - 0x40)
-    mflo    $a2
-    // 0x__7F is always empty and elided in the file, so decrement if larger
-    bnezl   $at, .kanji_lower_halfblock
-     mflo   $a2
-    addi    $a3, $a3, -1
-    mflo    $a2
+    /* Check if the codepoint is in the range 0x8140 to 0x9872. */
+    blt     a0, 0x8140, .out_of_range
+    bge     a0, 0x9873, .out_of_range
+    /* Characters with codepoints >= 0x8800 are kanji. Arrangement is regular,
+     * so convert index directly. */
+    li      a2, 0xBC
+    blt     a0, 0x8800, .nonkanji
+    /* 0xBC is number of glyphs in one block in the `kanji` file:
+     * 0x100 possible codepoints with the same byte1
+     * - 0x40 unused at beginning
+     * - 1 unused at 0x7F
+     * - 3 unused at 0xFD, 0xFE, 0xFF */
+    /* Get byte1 and adjust so starts at 0 */
+    srl     a1, a0, 8
+    addi    a1, a1, -0x88
+    mul     a2, a2, a1
+    /* Get byte2 and adjust so starts at 0 */
+    andi    a3, a0, 0xFF
+    addi    a3, a3, -0x40
+    /* 0x__7F is always empty and elided in the file, so decrement if larger */
+    blt     a3, 0x40, .kanji_lower_halfblock
+    addi    a3, a3, -1
 .kanji_lower_halfblock:
-    addi    $a3, $a3, 0x30A
-    add     $a3, $a3, $a2
-    jr      $ra
-     sll    $v0, $a3, 7
-     // returns (0x30A + (adjusted byte2) + (adjusted byte1) * 0xBC) * FONT_CHAR_TEX_SIZE
+    mflo    a2
+    addi    a3, a3, 0x30A
+    add     a3, a3, a2
+    sll    v0, a3, 7
+    jr      ra
+    /* returns (0x30A + (adjusted byte2) + (adjusted byte1) * 0xBC) * FONT_CHAR_TEX_SIZE */
 
-// Non-kanji are arranged with irregular gaps, use the lookup table.
+/* Non-kanji are arranged with irregular gaps, use the lookup table. */
 .nonkanji:
-    // Get byte1 and adjust so starts at 0
-    srl     $a1, $a0, 8
-    addi    $a1, $a1, -0x81
-    multu   $a2, $a1
-    // Get byte2 and adjust so starts at 0
-    andi    $a3, $a0, 0xFF
-    addi    $a3, $a3, -0x40
-    slti    $at, $a3, (0x80 - 0x40)
-    mflo    $a2
-    // 0x__7F is always empty and elided in the file, so decrement if larger
-    bnezl   $at, .nonkanji_lower_halfblock
-     mflo   $a2
-    addi    $a3, $a3, -1
-    mflo    $a2
+    /* Get byte1 and adjust so starts at 0 */
+    srl     a1, a0, 8
+    addi    a1, a1, -0x81
+    mul     a2, a2, a1
+    /* Get byte2 and adjust so starts at 0 */
+    andi    a3, a0, 0xFF
+    addi    a3, a3, -0x40
+    /* 0x__7F is always empty and elided in the file, so decrement if larger */
+    blt     a3, 0x40, .nonkanji_lower_halfblock
+    addi    a3, a3, -1
 .nonkanji_lower_halfblock:
-    add     $a3, $a3, $a2
-    lui     $a2, %hi(kantbl)
-    sll     $a3, $a3, 1
-    addiu   $a2, %lo(kantbl)
-    add     $a3, $a3, $a2
-    lh      $a2, ($a3)
-    jr      $ra
-     sll    $v0, $a2, 7
-     // returns kantbl[(adjusted byte2) + (adjusted byte1) * 0xBC] * FONT_CHAR_TEX_SIZE
+    mflo    a2
+    add     a3, a3, a2
+    sll     a3, a3, 1
+    la      a2, kantbl
+    add     a3, a3, a2
+    lh      a2, (a3)
+    sll     v0, a2, 7
+    jr      ra
+    /* returns kantbl[(adjusted byte2) + (adjusted byte1) * 0xBC] * FONT_CHAR_TEX_SIZE */
 .out_of_range:
-    jr      $ra
-     li     $v0, -1
+    li      v0, -1
+    jr      ra
 END(LeoGetKAdr)
 
 /**
@@ -129,7 +112,7 @@ END(LeoGetKAdr)
  * into blocks by high byte.
  */
 DATA(kantbl)
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x814_ */ .half 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000A, 0x000B, 0x000C, 0x000D, 0x000E, 0x000F
 /* 0x815_ */ .half 0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001A, 0x001B, 0x001C, 0x001D, 0x001E, 0x001F
 /* 0x816_ */ .half 0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002A, 0x002B, 0x002C, 0x002D, 0x002E, 0x002F
@@ -143,7 +126,7 @@ DATA(kantbl)
 /* 0x81E_ */ .half 0x0080, 0x0081, 0x0082, 0x0083, 0x0084, 0x0085, 0x0086, 0x0087, 0x0088, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x81F_ */ .half 0x0089, 0x008A, 0x008B, 0x008C, 0x008D, 0x008E, 0x008F, 0x0090, 0x0000, 0x0000, 0x0000, 0x0000, 0x0091
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x824_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0092
 /* 0x825_ */ .half 0x0093, 0x0094, 0x0095, 0x0096, 0x0097, 0x0098, 0x0099, 0x009A, 0x009B, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x826_ */ .half 0x009C, 0x009D, 0x009E, 0x009F, 0x00A0, 0x00A1, 0x00A2, 0x00A3, 0x00A4, 0x00A5, 0x00A6, 0x00A7, 0x00A8, 0x00A9, 0x00AA, 0x00AB
@@ -157,7 +140,7 @@ DATA(kantbl)
 /* 0x82E_ */ .half 0x0111, 0x0112, 0x0113, 0x0114, 0x0115, 0x0116, 0x0117, 0x0118, 0x0119, 0x011A, 0x011B, 0x011C, 0x011D, 0x011E, 0x011F, 0x0120
 /* 0x82F_ */ .half 0x0121, 0x0122, 0x0123, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x834_ */ .half 0x0124, 0x0125, 0x0126, 0x0127, 0x0128, 0x0129, 0x012A, 0x012B, 0x012C, 0x012D, 0x012E, 0x012F, 0x0130, 0x0131, 0x0132, 0x0133
 /* 0x835_ */ .half 0x0134, 0x0135, 0x0136, 0x0137, 0x0138, 0x0139, 0x013A, 0x013B, 0x013C, 0x013D, 0x013E, 0x013F, 0x0140, 0x0141, 0x0142, 0x0143
 /* 0x836_ */ .half 0x0144, 0x0145, 0x0146, 0x0147, 0x0148, 0x0149, 0x014A, 0x014B, 0x014C, 0x014D, 0x014E, 0x014F, 0x0150, 0x0151, 0x0152, 0x0153
@@ -171,7 +154,7 @@ DATA(kantbl)
 /* 0x83E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x83F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x844_ */ .half 0x01AB, 0x01AC, 0x01AD, 0x01AE, 0x01AF, 0x01B0, 0x01B1, 0x01B2, 0x01B3, 0x01B4, 0x01B5, 0x01B6, 0x01B7, 0x01B8, 0x01B9, 0x01BA
 /* 0x845_ */ .half 0x01BB, 0x01BC, 0x01BD, 0x01BE, 0x01BF, 0x01C0, 0x01C1, 0x01C2, 0x01C3, 0x01C4, 0x01C5, 0x01C6, 0x01C7, 0x01C8, 0x01C9, 0x01CA
 /* 0x846_ */ .half 0x01CB, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
@@ -185,7 +168,7 @@ DATA(kantbl)
 /* 0x84E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x84F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x854_ */ .half 0x020E, 0x020F, 0x0210, 0x0211, 0x0212, 0x0213, 0x0214, 0x0215, 0x0216, 0x0217, 0x0218, 0x0219, 0x021A, 0x021B, 0x021C, 0x021D
 /* 0x855_ */ .half 0x021E, 0x021F, 0x0220, 0x0221, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0222, 0x0223
 /* 0x856_ */ .half 0x0224, 0x0225, 0x0226, 0x0227, 0x0228, 0x0229, 0x022A, 0x022B, 0x022C, 0x022D, 0x022E, 0x022F, 0x0230, 0x0231, 0x0232, 0x0233
@@ -199,7 +182,7 @@ DATA(kantbl)
 /* 0x85E_ */ .half 0x026C, 0x026D, 0x026E, 0x026F, 0x0270, 0x0271, 0x0272, 0x0273, 0x0274, 0x0275, 0x0276, 0x0277, 0x0278, 0x0279, 0x027A, 0x027B
 /* 0x85F_ */ .half 0x027C, 0x027D, 0x027E, 0x027F, 0x0280, 0x0281, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x864_ */ .half 0x0282, 0x0283, 0x0284, 0x0285, 0x0286, 0x0287, 0x0288, 0x0289, 0x028A, 0x028B, 0x028C, 0x028D, 0x028E, 0x028F, 0x0290, 0x0291
 /* 0x865_ */ .half 0x0292, 0x0293, 0x0294, 0x0295, 0x0296, 0x0297, 0x0298, 0x0299, 0x029A, 0x029B, 0x029C, 0x029D, 0x029E, 0x029F, 0x0000, 0x0000
 /* 0x866_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
@@ -213,7 +196,7 @@ DATA(kantbl)
 /* 0x86E_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x86F_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 
-//                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F
+/*                 0x___0  0x___1  0x___2  0x___3  0x___4  0x___5  0x___6  0x___7  0x___8  0x___9  0x___A  0x___B  0x___C  0x___D  0x___E  0x___F */
 /* 0x874_ */ .half 0x02C0, 0x02C1, 0x02C2, 0x02C3, 0x02C4, 0x02C5, 0x02C6, 0x02C7, 0x02C8, 0x02C9, 0x02CA, 0x02CB, 0x02CC, 0x02CD, 0x02CE, 0x02CF
 /* 0x875_ */ .half 0x02D0, 0x02D1, 0x02D2, 0x02D3, 0x02D4, 0x02D5, 0x02D6, 0x02D7, 0x02D8, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
 /* 0x876_ */ .half 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
diff --git a/src/libultra/gu/libm_vals.s b/src/libultra/gu/libm_vals.s
index 18de1ae4f..91f2cadb3 100644
--- a/src/libultra/gu/libm_vals.s
+++ b/src/libultra/gu/libm_vals.s
@@ -1,8 +1,6 @@
 #include "ultra64/asm.h"
 
-.section .rodata
-
-.balign 16
+.rdata
 
 DATA(__libm_qnan_f)
     .word 0x7F810000
diff --git a/src/libultra/io/vimodefpallan1.c b/src/libultra/io/vimodefpallan1.c
index 37cb5ff55..5fb019cdf 100644
--- a/src/libultra/io/vimodefpallan1.c
+++ b/src/libultra/io/vimodefpallan1.c
@@ -16,15 +16,15 @@ OSViMode osViModeFpalLan1 = {
     {
         // comRegs
         VI_CTRL_TYPE_16 | VI_CTRL_GAMMA_DITHER_ON | VI_CTRL_GAMMA_ON | VI_CTRL_DIVOT_ON | VI_CTRL_ANTIALIAS_MODE_1 |
-            VI_CTRL_PIXEL_ADV_3, // ctrl
-        WIDTH(320),              // width
-        BURST(58, 30, 4, 69),    // burst
-        VSYNC(625),              // vSync
-        HSYNC(3177, 23),         // hSync
-        LEAP(3183, 3181),        // leap
-        HSTART(128, 768),        // hStart
-        SCALE(2, 0),             // xScale
-        VCURRENT(0),             // vCurrent
+            VI_CTRL_PIXEL_ADV(3), // ctrl
+        WIDTH(320),               // width
+        BURST(58, 30, 4, 69),     // burst
+        VSYNC(625),               // vSync
+        HSYNC(3177, 23),          // hSync
+        LEAP(3183, 3181),         // leap
+        HSTART(128, 768),         // hStart
+        SCALE(2, 0),              // xScale
+        VCURRENT(0),              // vCurrent
     },
     { // fldRegs
       {
diff --git a/src/libultra/io/vimodempallan1.c b/src/libultra/io/vimodempallan1.c
index bcc4273af..23d53987b 100644
--- a/src/libultra/io/vimodempallan1.c
+++ b/src/libultra/io/vimodempallan1.c
@@ -16,15 +16,15 @@ OSViMode osViModeMpalLan1 = {
     {
         // comRegs
         VI_CTRL_TYPE_16 | VI_CTRL_GAMMA_DITHER_ON | VI_CTRL_GAMMA_ON | VI_CTRL_DIVOT_ON | VI_CTRL_ANTIALIAS_MODE_1 |
-            VI_CTRL_PIXEL_ADV_3, // ctrl
-        WIDTH(320),              // width
-        BURST(57, 30, 5, 70),    // burst
-        VSYNC(525),              // vSync
-        HSYNC(3089, 4),          // hSync
-        LEAP(3097, 3098),        // leap
-        HSTART(108, 748),        // hStart
-        SCALE(2, 0),             // xScale
-        VCURRENT(0),             // vCurrent
+            VI_CTRL_PIXEL_ADV(3), // ctrl
+        WIDTH(320),               // width
+        BURST(57, 30, 5, 70),     // burst
+        VSYNC(525),               // vSync
+        HSYNC(3089, 4),           // hSync
+        LEAP(3097, 3098),         // leap
+        HSTART(108, 748),         // hStart
+        SCALE(2, 0),              // xScale
+        VCURRENT(0),              // vCurrent
     },
     { // fldRegs
       {
diff --git a/src/libultra/io/vimodentsclan1.c b/src/libultra/io/vimodentsclan1.c
index a29d15129..19a7160ac 100644
--- a/src/libultra/io/vimodentsclan1.c
+++ b/src/libultra/io/vimodentsclan1.c
@@ -16,15 +16,15 @@ OSViMode osViModeNtscLan1 = {
     {
         // comRegs
         VI_CTRL_TYPE_16 | VI_CTRL_GAMMA_DITHER_ON | VI_CTRL_GAMMA_ON | VI_CTRL_DIVOT_ON | VI_CTRL_ANTIALIAS_MODE_1 |
-            VI_CTRL_PIXEL_ADV_3, // ctrl
-        WIDTH(320),              // width
-        BURST(57, 34, 5, 62),    // burst
-        VSYNC(525),              // vSync
-        HSYNC(3093, 0),          // hSync
-        LEAP(3093, 3093),        // leap
-        HSTART(108, 748),        // hStart
-        SCALE(2, 0),             // xScale
-        VCURRENT(0),             // vCurrent
+            VI_CTRL_PIXEL_ADV(3), // ctrl
+        WIDTH(320),               // width
+        BURST(57, 34, 5, 62),     // burst
+        VSYNC(525),               // vSync
+        HSYNC(3093, 0),           // hSync
+        LEAP(3093, 3093),         // leap
+        HSTART(108, 748),         // hStart
+        SCALE(2, 0),              // xScale
+        VCURRENT(0),              // vCurrent
     },
     { // fldRegs
       {
diff --git a/src/libultra/io/vimodepallan1.c b/src/libultra/io/vimodepallan1.c
index d656dc4f9..7a8db603f 100644
--- a/src/libultra/io/vimodepallan1.c
+++ b/src/libultra/io/vimodepallan1.c
@@ -16,15 +16,15 @@ OSViMode osViModePalLan1 = {
     {
         // comRegs
         VI_CTRL_TYPE_16 | VI_CTRL_GAMMA_DITHER_ON | VI_CTRL_GAMMA_ON | VI_CTRL_DIVOT_ON | VI_CTRL_ANTIALIAS_MODE_1 |
-            VI_CTRL_PIXEL_ADV_3, // ctrl
-        WIDTH(320),              // width
-        BURST(58, 30, 4, 69),    // burst
-        VSYNC(625),              // vSync
-        HSYNC(3177, 23),         // hSync
-        LEAP(3183, 3181),        // leap
-        HSTART(128, 768),        // hStart
-        SCALE(2, 0),             // xScale
-        VCURRENT(0),             // vCurrent
+            VI_CTRL_PIXEL_ADV(3), // ctrl
+        WIDTH(320),               // width
+        BURST(58, 30, 4, 69),     // burst
+        VSYNC(625),               // vSync
+        HSYNC(3177, 23),          // hSync
+        LEAP(3183, 3181),         // leap
+        HSTART(128, 768),         // hStart
+        SCALE(2, 0),              // xScale
+        VCURRENT(0),              // vCurrent
     },
     { // fldRegs
       {
diff --git a/src/libultra/libc/bcmp.s b/src/libultra/libc/bcmp.s
index df6692feb..dcd5bc002 100644
--- a/src/libultra/libc/bcmp.s
+++ b/src/libultra/libc/bcmp.s
@@ -1,93 +1,89 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
+.text
 
-.section .text
+LEAF(bcmp)
+    xor     v0, a0, a1
+    blt     a2, 0x10, bytecmp
 
-.balign 16
+    and     v0, v0, 3
+    negu    t8, a0
+    bnez    v0, unaligncmp
+
+    and     t8, t8, 3
+    subu    a2, a2, t8
+    beqz    t8, wordcmp
+
+    move    v0, v1
+    lwl     v0, (a0)
+    lwl     v1, (a1)
+    addu    a0, a0, t8
+    addu    a1, a1, t8
+    bne     v0, v1, cmpne
 
-LEAF(bcmp)
-    slti    $at, $a2, 0x10
-    bnez    $at, bytecmp
-     xor    $v0, $a0, $a1
-    andi    $v0, $v0, 3
-    bnez    $v0, unaligncmp
-     negu   $t8, $a0
-    andi    $t8, $t8, 3
-    beqz    $t8, wordcmp
-     subu   $a2, $a2, $t8
-    move    $v0, $v1
-    lwl     $v0, ($a0)
-    lwl     $v1, ($a1)
-    addu    $a0, $a0, $t8
-    addu    $a1, $a1, $t8
-    bne     $v0, $v1, cmpne
 wordcmp:
-     li     $at, ~3
-    and     $a3, $a2, $at
-    beqz    $a3, bytecmp
-     subu   $a2, $a2, $a3
-    addu    $a3, $a3, $a0
-    lw      $v0, ($a0)
+    and     a3, a2, ~3
+    subu    a2, a2, a3
+    beqz    a3, bytecmp
+
+    addu    a3, a3, a0
 1:
-    lw      $v1, ($a1)
-    addiu   $a0, $a0, 4
-    addiu   $a1, $a1, 4
-    bne     $v0, $v1, cmpne
-     nop
-    bnel    $a0, $a3, 1b
-     lw     $v0, ($a0)
+    lw      v0, (a0)
+    lw      v1, (a1)
+    addu    a0, a0, 4
+    addu    a1, a1, 4
+    bne     v0, v1, cmpne
+    bne     a0, a3, 1b
+
     b       bytecmp
-     nop
+
 unaligncmp:
-    negu    $a3, $a1
-    andi    $a3, $a3, 3
-    beqz    $a3, partaligncmp
-     subu   $a2, $a2, $a3
-    addu    $a3, $a3, $a0
-    lbu     $v0, ($a0)
+    negu    a3, a1
+    and     a3, a3, 3
+    subu    a2, a2, a3
+    beqz    a3, partaligncmp
+
+    addu    a3, a3, a0
 1:
-    lbu     $v1, ($a1)
-    addiu   $a0, $a0, 1
-    addiu   $a1, $a1, 1
-    bne     $v0, $v1, cmpne
-     nop
-    bnel    $a0, $a3, 1b
-     lbu    $v0, ($a0)
+    lbu     v0, (a0)
+    lbu     v1, (a1)
+    addu    a0, a0, 1
+    addu    a1, a1, 1
+    bne     v0, v1, cmpne
+    bne     a0, a3, 1b
+
 partaligncmp:
-    li      $at, ~3
-    and     $a3, $a2, $at
-    beqz    $a3, bytecmp
-     subu   $a2, $a2, $a3
-    addu    $a3, $a3, $a0
-    lwl     $v0, ($a0)
+    and     a3, a2, ~3
+    subu    a2, a2, a3
+    beqz    a3, bytecmp
+
+    addu    a3, a3, a0
 1:
-    lw      $v1, ($a1)
-    lwr     $v0, 3($a0)
-    addiu   $a0, $a0, 4
-    addiu   $a1, $a1, 4
-    bne     $v0, $v1, cmpne
-     nop
-    bnel    $a0, $a3, 1b
-     lwl    $v0, ($a0)
+    lwl     v0, (a0)
+    lw      v1, (a1)
+    lwr     v0, 3(a0)
+    addu    a0, a0, 4
+    addu    a1, a1, 4
+    bne     v0, v1, cmpne
+    bne     a0, a3, 1b
+
 bytecmp:
-    blez    $a2, cmpdone
-     addu   $a3, $a2, $a0
-    lbu     $v0, ($a0)
+    addu    a3, a2, a0
+    blez    a2, cmpdone
 1:
-    lbu     $v1, ($a1)
-    addiu   $a0, $a0, 1
-    addiu   $a1, $a1, 1
-    bne     $v0, $v1, cmpne
-     nop
-    bnel    $a0, $a3, 1b
-     lbu    $v0, ($a0)
+    lbu     v0, (a0)
+    lbu     v1, (a1)
+    addu    a0, a0, 1
+    addu    a1, a1, 1
+    bne     v0, v1, cmpne
+    bne     a0, a3, 1b
+
 cmpdone:
-    jr      $ra
-     move   $v0, $zero
+    move    v0, zero
+    jr      ra
 
 cmpne:
-    jr      $ra
-     li     $v0, 1
+    li      v0, 1
+    jr      ra
 END(bcmp)
diff --git a/src/libultra/libc/bcopy.s b/src/libultra/libc/bcopy.s
index e1240f113..dcb6ad13c 100644
--- a/src/libultra/libc/bcopy.s
+++ b/src/libultra/libc/bcopy.s
@@ -1,233 +1,211 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(bcopy)
-    beqz    $a2, ret
-     move   $a3, $a1
-    beq     $a0, $a1, ret
-     slt    $at, $a1, $a0
-    bnezl   $at, goforwards
-     slti   $at, $a2, 0x10
-    add     $v0, $a0, $a2
-    slt     $at, $a1, $v0
-    beql    $at, $zero, goforwards
-     slti   $at, $a2, 0x10
+    move    a3, a1
+    beqz    a2, ret
+    beq     a0, a1, ret
+    blt     a1, a0, goforwards
+    add     v0, a0, a2
+    bge     a1, v0, goforwards
     b       gobackwards
-     slti   $at, $a2, 0x10
-    slti    $at, $a2, 0x10
+
 goforwards:
-    bnez    $at, forwards_bytecopy
-     nop
-    andi    $v0, $a0, 3
-    andi    $v1, $a1, 3
-    beq     $v0, $v1, forwalignable
-     nop
+    blt     a2, 0x10, forwards_bytecopy
+    and     v0, a0, 3
+    and     v1, a1, 3
+    beq     v0, v1, forwalignable
+
 forwards_bytecopy:
-    beqz    $a2, ret
-     nop
-    addu    $v1, $a0, $a2
+    beqz    a2, ret
+    addu    v1, a0, a2
 99:
-    lb      $v0, ($a0)
-    addiu   $a0, $a0, 1
-    addiu   $a1, $a1, 1
-    bne     $a0, $v1, 99b
-     sb     $v0, -1($a1)
+    lb      v0, (a0)
+    addu    a0, a0, 1
+    sb      v0, (a1)
+    addu    a1, a1, 1
+    bne     a0, v1, 99b
 ret:
-    jr      $ra
-     move   $v0, $a3
+    move    v0, a3
+    jr      ra
 
 forwalignable:
-    beqz    $v0, forwards_32
-     li     $at, 1
-    beq     $v0, $at, forw_copy3
-     li     $at, 2
-    beql    $v0, $at, forw_copy2
-     lh     $v0, ($a0)
-    lb      $v0, ($a0)
-    addiu   $a0, $a0, 1
-    addiu   $a1, $a1, 1
-    addiu   $a2, $a2, -1
+    beqz    v0, forwards_32
+    beq     v0, 1, forw_copy3
+    beq     v0, 2, forw_copy2
+
+    lb      v0, (a0)
+    addu    a0, a0, 1
+    sb      v0, (a1)
+    addu    a1, a1, 1
+    addu    a2, a2, -1
     b       forwards_32
-     sb     $v0, -1($a1)
-    lh      $v0, ($a0)
+
 forw_copy2:
-    addiu   $a0, $a0, 2
-    addiu   $a1, $a1, 2
-    addiu   $a2, $a2, -2
+    lh      v0, (a0)
+    addu    a0, a0, 2
+    sh      v0, (a1)
+    addu    a1, a1, 2
+    addu    a2, a2, -2
     b       forwards_32
-     sh     $v0, -2($a1)
+
 forw_copy3:
-    lb      $v0, ($a0)
-    lh      $v1, 1($a0)
-    addiu   $a0, $a0, 3
-    addiu   $a1, $a1, 3
-    addiu   $a2, $a2, -3
-    sb      $v0, -3($a1)
-    sh      $v1, -2($a1)
+    lb      v0, (a0)
+    lh      v1, 1(a0)
+    addiu   a0, a0, 3
+    sb      v0, (a1)
+    sh      v1, 1(a1)
+    addiu   a1, a1, 3
+    addiu   a2, a2, -3
 
 forwards:
 forwards_32:
-    slti    $at, $a2, 0x20
-    bnezl   $at, forwards_16_
-     slti   $at, $a2, 0x10
-    lw      $v0, ($a0)
-    lw      $v1, 4($a0)
-    lw      $t0, 8($a0)
-    lw      $t1, 0xC($a0)
-    lw      $t2, 0x10($a0)
-    lw      $t3, 0x14($a0)
-    lw      $t4, 0x18($a0)
-    lw      $t5, 0x1C($a0)
-    addiu   $a0, $a0, 0x20
-    addiu   $a1, $a1, 0x20
-    addiu   $a2, $a2, -0x20
-    sw      $v0, -0x20($a1)
-    sw      $v1, -0x1C($a1)
-    sw      $t0, -0x18($a1)
-    sw      $t1, -0x14($a1)
-    sw      $t2, -0x10($a1)
-    sw      $t3, -0xC($a1)
-    sw      $t4, -8($a1)
+    blt     a2, 32, forwards_16
+    lw      v0, 0(a0)
+    lw      v1, 4(a0)
+    lw      t0, 8(a0)
+    lw      t1, 12(a0)
+    lw      t2, 16(a0)
+    lw      t3, 20(a0)
+    lw      t4, 24(a0)
+    lw      t5, 28(a0)
+    addiu   a0, a0, 32
+    sw      v0, 0(a1)
+    sw      v1, 4(a1)
+    sw      t0, 8(a1)
+    sw      t1, 12(a1)
+    sw      t2, 16(a1)
+    sw      t3, 20(a1)
+    sw      t4, 24(a1)
+    sw      t5, 28(a1)
+    addiu   a1, a1, 32
+    addiu   a2, a2, -32
     b       forwards_32
-     sw     $t5, -4($a1)
+
 forwards_16:
-    slti    $at, $a2, 0x10
-forwards_16_: // fake label due to branch likely optimization
-    bnezl   $at, forwards_4_
-     slti   $at, $a2, 4
-    lw      $v0, ($a0)
-    lw      $v1, 4($a0)
-    lw      $t0, 8($a0)
-    lw      $t1, 0xC($a0)
-    addiu   $a0, $a0, 0x10
-    addiu   $a1, $a1, 0x10
-    addiu   $a2, $a2, -0x10
-    sw      $v0, -0x10($a1)
-    sw      $v1, -0xC($a1)
-    sw      $t0, -8($a1)
+    blt     a2, 16, forwards_4
+    lw      v0, 0(a0)
+    lw      v1, 4(a0)
+    lw      t0, 8(a0)
+    lw      t1, 12(a0)
+    addiu   a0, a0, 16
+    sw      v0, 0(a1)
+    sw      v1, 4(a1)
+    sw      t0, 8(a1)
+    sw      t1, 12(a1)
+    addiu   a1, a1, 16
+    addiu   a2, a2, -16
     b       forwards_16
-     sw     $t1, -4($a1)
+
 forwards_4:
-    slti    $at, $a2, 4
-forwards_4_: // fake label due to branch likely optimization
-    bnez    $at, forwards_bytecopy
-     nop
-    lw      $v0, ($a0)
-    addiu   $a0, $a0, 4
-    addiu   $a1, $a1, 4
-    addiu   $a2, $a2, -4
+    blt     a2, 4, forwards_bytecopy
+
+    lw      v0, 0(a0)
+    addiu   a0, a0, 4
+    sw      v0, 0(a1)
+    addiu   a1, a1, 4
+    addiu   a2, a2, -4
     b       forwards_4
-     sw     $v0, -4($a1)
-    slti    $at, $a2, 0x10
+
 gobackwards:
-    add     $a0, $a0, $a2
-    bnez    $at, backwards_bytecopy
-     add    $a1, $a1, $a2
-    andi    $v0, $a0, 3
-    andi    $v1, $a1, 3
-    beq     $v0, $v1, backalignable
-     nop
+    add     a0, a0,a2
+    add     a1, a1,a2
+    blt     a2, 16, backwards_bytecopy
+
+    andi    v0, a0, 0x3
+    andi    v1, a1, 0x3
+    beq     v0, v1, backalignable
+
 backwards_bytecopy:
-    beqz    $a2, ret
-     nop
-    addiu   $a0, $a0, -1
-    addiu   $a1, $a1, -1
-    subu    $v1, $a0, $a2
+    beqz    a2, ret
+    addiu   a0, a0, -1
+    addiu   a1, a1, -1
+    subu    v1, a0,a2
 99:
-    lb      $v0, ($a0)
-    addiu   $a0, $a0, -1
-    addiu   $a1, $a1, -1
-    bne     $a0, $v1, 99b
-     sb     $v0, 1($a1)
-    jr      $ra
-     move   $v0, $a3
+    lb      v0, 0(a0)
+    addiu   a0, a0, -1
+    sb      v0, 0(a1)
+    addiu   a1, a1, -1
+    bne     a0, v1,99b
+
+    move    v0, a3
+    jr      ra
 
 backalignable:
-    beqz    $v0, backwards_32
-     li     $at, 3
-    beq     $v0, $at, back_copy3
-     li     $at, 2
-    beql    $v0, $at, back_copy2
-     lh     $v0, -2($a0)
-    lb      $v0, -1($a0)
-    addiu   $a0, $a0, -1
-    addiu   $a1, $a1, -1
-    addiu   $a2, $a2, -1
-    b       backwards_32
-     sb     $v0, ($a1)
-    lh      $v0, -2($a0)
+    beqz    v0, backwards
+    beq     v0, 3, back_copy3
+    beq     v0, 2, back_copy2
+    lb      v0, -1(a0)
+    addiu   a0, a0, -1
+    sb      v0, -1(a1)
+    addiu   a1, a1, -1
+    addiu   a2, a2, -1
+    b       backwards
+
 back_copy2:
-    addiu   $a0, $a0, -2
-    addiu   $a1, $a1, -2
-    addiu   $a2, $a2, -2
-    b       backwards_32
-     sh     $v0, ($a1)
+    lh      v0, -2(a0)
+    addiu   a0, a0, -2
+    sh      v0, -2(a1)
+    addiu   a1, a1, -2
+    addiu   a2, a2, -2
+    b       backwards
+
 back_copy3:
-    lb      $v0, -1($a0)
-    lh      $v1, -3($a0)
-    addiu   $a0, $a0, -3
-    addiu   $a1, $a1, -3
-    addiu   $a2, $a2, -3
-    sb      $v0, 2($a1)
-    sh      $v1, ($a1)
+    lb      v0, -1(a0)
+    lh      v1, -3(a0)
+    addiu   a0, a0, -3
+    sb      v0, -1(a1)
+    sh      v1, -3(a1)
+    addiu   a1, a1, -3
+    addiu   a2, a2, -3
 
 backwards:
 backwards_32:
-    slti    $at, $a2, 0x20
-    bnezl   $at, backwards_16_
-     slti   $at, $a2, 0x10
-    lw      $v0, -4($a0)
-    lw      $v1, -8($a0)
-    lw      $t0, -0xc($a0)
-    lw      $t1, -0x10($a0)
-    lw      $t2, -0x14($a0)
-    lw      $t3, -0x18($a0)
-    lw      $t4, -0x1c($a0)
-    lw      $t5, -0x20($a0)
-    addiu   $a0, $a0, -0x20
-    addiu   $a1, $a1, -0x20
-    addiu   $a2, $a2, -0x20
-    sw      $v0, 0x1C($a1)
-    sw      $v1, 0x18($a1)
-    sw      $t0, 0x14($a1)
-    sw      $t1, 0x10($a1)
-    sw      $t2, 0xC($a1)
-    sw      $t3, 8($a1)
-    sw      $t4, 4($a1)
+    blt     a2, 32, backwards_16
+    lw      v0, -4(a0)
+    lw      v1, -8(a0)
+    lw      t0, -12(a0)
+    lw      t1, -16(a0)
+    lw      t2, -20(a0)
+    lw      t3, -24(a0)
+    lw      t4, -28(a0)
+    lw      t5, -32(a0)
+    addiu   a0, a0, -32
+    sw      v0, -4(a1)
+    sw      v1, -8(a1)
+    sw      t0, -12(a1)
+    sw      t1, -16(a1)
+    sw      t2, -20(a1)
+    sw      t3, -24(a1)
+    sw      t4, -28(a1)
+    sw      t5, -32(a1)
+    addiu   a1, a1, -32
+    addiu   a2, a2, -32
     b       backwards_32
-     sw     $t5, ($a1)
+
 backwards_16:
-    slti    $at, $a2, 0x10
-backwards_16_: // fake label due to branch likely optimization
-    bnezl   $at, backwards_4_
-     slti   $at, $a2, 4
-    lw      $v0, -4($a0)
-    lw      $v1, -8($a0)
-    lw      $t0, -0xC($a0)
-    lw      $t1, -0x10($a0)
-    addiu   $a0, $a0, -0x10
-    addiu   $a1, $a1, -0x10
-    addiu   $a2, $a2, -0x10
-    sw      $v0, 0xC($a1)
-    sw      $v1, 8($a1)
-    sw      $t0, 4($a1)
+    blt     a2, 16, backwards_4
+    lw      v0, -4(a0)
+    lw      v1, -8(a0)
+    lw      t0, -12(a0)
+    lw      t1, -16(a0)
+    addiu   a0, a0, -16
+    sw      v0, -4(a1)
+    sw      v1, -8(a1)
+    sw      t0, -12(a1)
+    sw      t1, -16(a1)
+    addiu   a1, a1, -16
+    addiu   a2, a2, -16
     b       backwards_16
-     sw     $t1, ($a1)
+
 backwards_4:
-    slti    $at, $a2, 4
-backwards_4_: // fake label due to branch likely optimization
-    bnez    $at, backwards_bytecopy
-     nop
-    lw      $v0, -4($a0)
-    addiu   $a0, $a0, -4
-    addiu   $a1, $a1, -4
-    addiu   $a2, $a2, -4
+    blt     a2, 4, backwards_bytecopy
+    lw      v0, -4(a0)
+    addiu   a0, a0, -4
+    sw      v0, -4(a1)
+    addiu   a1, a1, -4
+    addiu   a2, a2, -4
     b       backwards_4
-     sw     $v0, ($a1)
 END(bcopy)
diff --git a/src/libultra/libc/bzero.s b/src/libultra/libc/bzero.s
index 5323a92d7..9c6552f65 100644
--- a/src/libultra/libc/bzero.s
+++ b/src/libultra/libc/bzero.s
@@ -1,65 +1,59 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
+.text
 
-.section .text
+LEAF(bzero)
+    negu    v1, a0
+    blt     a1, 0xC, bytezero
 
-.balign 16
+    and     v1, v1, 3
+    subu    a1, a1, v1
+    beqz    v1, blkzero
 
-LEAF(bzero)
-    slti    $at, $a1, 0xC
-    bnez    $at, bytezero
-     negu   $v1, $a0
-    andi    $v1, $v1, 3
-    beqz    $v1, blkzero
-     subu   $a1, $a1, $v1
-    swl     $zero, ($a0)
-    addu    $a0, $a0, $v1
+    swl     zero, (a0)
+    addu    a0, a0, v1
 blkzero:
-    // align backwards to 0x20
-    li      $at, ~0x1F
-    and     $a3, $a1, $at
-    // If the result is zero, the amount to zero is less than 0x20 bytes
-    beqz    $a3, wordzero
-     subu   $a1, $a1, $a3
-    // zero in blocks of 0x20 at a time
-    addu    $a3, $a3, $a0
+    /* align backwards to 0x20 */
+    and     a3, a1, ~(0x20 - 1)
+    /* If the result is zero, the amount to zero is less than 0x20 bytes */
+    subu    a1, a1, a3
+    beqz    a3, wordzero
+    /* zero in blocks of 0x20 at a time */
+    addu    a3, a3, a0
 1:
-    addiu   $a0, $a0, 0x20
-    sw      $zero, -0x20($a0)
-    sw      $zero, -0x1C($a0)
-    sw      $zero, -0x18($a0)
-    sw      $zero, -0x14($a0)
-    sw      $zero, -0x10($a0)
-    sw      $zero, -0xC($a0)
-    sw      $zero, -8($a0)
-    bne     $a0, $a3, 1b
-     sw     $zero, -4($a0)
+    sw      zero, 0(a0)
+    sw      zero, 4(a0)
+    sw      zero, 8(a0)
+    sw      zero, 12(a0)
+    addiu   a0, a0, 0x20
+    sw      zero, -16(a0)
+    sw      zero, -12(a0)
+    sw      zero, -8(a0)
+    sw      zero, -4(a0)
+    bne     a0, a3, 1b
+
 wordzero:
-    // align backwards to 0x4
-    li      $at, ~3
-    and     $a3, $a1, $at
-    // If the result is zero, the amount to zero is less than 0x4 bytes
-    beqz    $a3, bytezero
-     subu   $a1, $a1, $a3
-    // zero one word at a time
-    addu    $a3, $a3, $a0
+    /* align backwards to 0x4 */
+    and     a3, a1, ~3
+    /* If the result is zero, the amount to zero is less than 0x4 bytes */
+    subu    a1, a1, a3
+    beqz    a3, bytezero
+    /* zero one word at a time */
+    addu    a3, a3, a0
 1:
-    addiu   $a0, $a0, 4
-    bne     $a0, $a3, 1b
-     sw     $zero, -4($a0)
+    addu    a0, a0, 4
+    sw      zero, -4(a0)
+    bne     a0, a3, 1b
 bytezero:
-    // test if nothing left to zero
-    blez    $a1, zerodone
-     nop
-    // zero one byte at a time
-    addu    $a1, $a1, $a0
+    /* test if nothing left to zero */
+    blez    a1, zerodone
+    /* zero one byte at a time */
+    addu    a1, a1, a0
 1:
-    addiu   $a0, $a0, 1
-    bne     $a0, $a1, 1b
-     sb     $zero, -1($a0)
+    sb      zero, (a0)
+    addiu   a0, a0, 1
+    bne     a0, a1, 1b
 zerodone:
-    jr      $ra
-     nop
+    jr      ra
 END(bzero)
diff --git a/src/libultra/mgu/mtxf2l.s b/src/libultra/mgu/mtxf2l.s
index edbb675a8..1fada6b53 100644
--- a/src/libultra/mgu/mtxf2l.s
+++ b/src/libultra/mgu/mtxf2l.s
@@ -1,40 +1,36 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 32
+.text
+.align 5
 
 #define MTX_INTPART  0
 #define MTX_FRACPART 0x20
 
 LEAF(guMtxF2L)
-    li      $at, 0x47800000 // 65536.0f
-    mtc1    $at, $f0
-    li      $t9, 0xFFFF0000
-    addiu   $t8, $a1, MTX_FRACPART
+    li.s    fv0, 65536.0
+    li      t9, 0xFFFF0000
+    addu    t8, a1, MTX_FRACPART
 1:
-    lwc1    $f4, ($a0)
-    lwc1    $f10, 4($a0)
-    addiu   $a1, $a1, 4
-    mul.s   $f6, $f4, $f0
-    addiu   $a0, $a0, 8
-    mul.s   $f16, $f10, $f0
-    trunc.w.s $f8, $f6
-    trunc.w.s $f18, $f16
-    mfc1    $t0, $f8
-    mfc1    $t1, $f18
-    and     $t2, $t0, $t9
-    sll     $t5, $t0, 0x10
-    srl     $t3, $t1, 0x10
-    andi    $t6, $t1, 0xFFFF
-    or      $t4, $t2, $t3
-    or      $t7, $t5, $t6
-    sw      $t4, (MTX_INTPART-4)($a1)
-    bne     $a1, $t8, 1b
-     sw     $t7, (MTX_FRACPART-4)($a1)
-    jr      $ra
-     nop
+    lwc1    ft0, 0(a0)
+    lwc1    ft3, 4(a0)
+    mul.s   ft1, ft0, fv0
+    mul.s   ft4, ft3, fv0
+    trunc.w.s ft2, ft1
+    trunc.w.s ft5, ft4
+    mfc1    t0, ft2
+    mfc1    t1, ft5
+    srl     t3, t1, 0x10
+    and     t6, t1, 0xFFFF
+    and     t2, t0, t9
+    sll     t5, t0, 0x10
+    or      t4, t2, t3
+    or      t7, t5, t6
+    sw      t4, (MTX_INTPART)(a1)
+    sw      t7, (MTX_FRACPART)(a1)
+    addu    a0, a0, 8
+    addu    a1, a1, 4
+    bne     a1, t8, 1b
+
+    jr      ra
 END(guMtxF2L)
diff --git a/src/libultra/mgu/mtxident.s b/src/libultra/mgu/mtxident.s
index fb0e4c44a..7f074a552 100644
--- a/src/libultra/mgu/mtxident.s
+++ b/src/libultra/mgu/mtxident.s
@@ -1,29 +1,27 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noreorder
-
-.section .text
-
-.balign 32
+.text
+.align 5
 
 LEAF(guMtxIdent)
-    addi    $t0, $zero, 1
-    sll     $t1, $t0, 0x10
-    sw      $t1, ($a0)
-    sw      $zero, 4($a0)
-    sw      $t0, 8($a0)
-    sw      $zero, 0xc($a0)
-    sw      $zero, 0x10($a0)
-    sw      $t1, 0x14($a0)
-    sw      $zero, 0x18($a0)
-    sw      $t0, 0x1C($a0)
-    sw      $zero, 0x20($a0)
-    sw      $zero, 0x24($a0)
-    sw      $zero, 0x28($a0)
-    sw      $zero, 0x2c($a0)
-    sw      $zero, 0x30($a0)
-    sw      $zero, 0x34($a0)
-    sw      $zero, 0x38($a0)
-    jr      $ra
-     sw     $zero, 0x3C($a0)
+    add     t0, zero, 1
+    sll     t1, t0, 0x10
+    sw      t1,   0x00(a0)
+    sw      zero, 0x04(a0)
+    sw      t0,   0x08(a0)
+    sw      zero, 0x0C(a0)
+    sw      zero, 0x10(a0)
+    sw      t1,   0x14(a0)
+    sw      zero, 0x18(a0)
+    sw      t0,   0x1C(a0)
+    sw      zero, 0x20(a0)
+    sw      zero, 0x24(a0)
+    sw      zero, 0x28(a0)
+    sw      zero, 0x2c(a0)
+    sw      zero, 0x30(a0)
+    sw      zero, 0x34(a0)
+    sw      zero, 0x38(a0)
+    sw      zero, 0x3C(a0)
+    jr      ra
 END(guMtxIdent)
diff --git a/src/libultra/mgu/mtxidentf.s b/src/libultra/mgu/mtxidentf.s
index 583fc2218..490b79e4b 100644
--- a/src/libultra/mgu/mtxidentf.s
+++ b/src/libultra/mgu/mtxidentf.s
@@ -1,28 +1,26 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noreorder
-
-.section .text
-
-.balign 32
+.text
+.align 5
 
 LEAF(guMtxIdentF)
-    li      $t0, 0x3F800000 // 1.0f
-    sw      $t0, ($a0)
-    sw      $zero, 4($a0)
-    sw      $zero, 8($a0)
-    sw      $zero, 0xC($a0)
-    sw      $zero, 0x10($a0)
-    sw      $t0, 0x14($a0)
-    sw      $zero, 0x18($a0)
-    sw      $zero, 0x1C($a0)
-    sw      $zero, 0x20($a0)
-    sw      $zero, 0x24($a0)
-    sw      $t0, 0x28($a0)
-    sw      $zero, 0x2C($a0)
-    sw      $zero, 0x30($a0)
-    sw      $zero, 0x34($a0)
-    sw      $zero, 0x38($a0)
-    jr      $ra
-     sw     $t0, 0x3C($a0)
+    li.s    t0,   1.0
+    sw      t0,   0x00(a0)
+    sw      zero, 0x04(a0)
+    sw      zero, 0x08(a0)
+    sw      zero, 0x0C(a0)
+    sw      zero, 0x10(a0)
+    sw      t0,   0x14(a0)
+    sw      zero, 0x18(a0)
+    sw      zero, 0x1C(a0)
+    sw      zero, 0x20(a0)
+    sw      zero, 0x24(a0)
+    sw      t0,   0x28(a0)
+    sw      zero, 0x2C(a0)
+    sw      zero, 0x30(a0)
+    sw      zero, 0x34(a0)
+    sw      zero, 0x38(a0)
+    sw      t0,   0x3C(a0)
+    jr      ra
 END(guMtxIdentF)
diff --git a/src/libultra/mgu/mtxl2f.s b/src/libultra/mgu/mtxl2f.s
index 9298da37c..b95e3aca7 100644
--- a/src/libultra/mgu/mtxl2f.s
+++ b/src/libultra/mgu/mtxl2f.s
@@ -1,41 +1,43 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 32
+.text
+.align 5
 
 #define MTX_INTPART  0
 #define MTX_FRACPART 0x20
 
+#define FIXTOF 0.0000152587890625 /* 1.0f / 65536.0f */
+
 LEAF(guMtxL2F)
-    li      $at, 0x37800000 // 1.0f / 65536.0f
-    mtc1    $at, $f0
-    li      $t9, 0xFFFF0000
-    addiu   $t8, $a1, MTX_FRACPART
+    li.s    fv0, FIXTOF
+    li      t9, 0xFFFF0000
+    addiu   t8, a1, MTX_FRACPART
 1:
-    lw      $t0, MTX_INTPART($a1)
-    lw      $t1, MTX_FRACPART($a1)
-    addiu   $a1, $a1, 4
-    and     $t2, $t0, $t9
-    srl     $t3, $t1, 0x10
-    or      $t4, $t2, $t3
-    mtc1    $t4, $f4
-    sll     $t5, $t0, 0x10
-    andi    $t6, $t1, 0xFFFF
-    or      $t7, $t5, $t6
-    cvt.s.w $f6, $f4
-    mtc1    $t7, $f10
-    addiu   $a0, $a0, 8
-    cvt.s.w $f16, $f10
-    mul.s   $f8, $f6, $f0
-    nop
-    mul.s   $f18, $f16, $f0
-    swc1    $f8, -8($a0)
-    bne     $a1, $t8, 1b
-     swc1   $f18, -4($a0)
-    jr      $ra
-     nop
+    lw      t0, MTX_INTPART(a1)
+    lw      t1, MTX_FRACPART(a1)
+
+    and     t2, t0, t9
+    srl     t3, t1, 0x10
+    or      t4, t2, t3
+
+    sll     t5, t0, 0x10
+    and     t6, t1, 0xFFFF
+    or      t7, t5, t6
+
+    mtc1    t4, ft0
+    cvt.s.w ft1, ft0
+    mul.s   ft2, ft1, fv0
+
+    mtc1    t7, ft3
+    cvt.s.w ft4, ft3
+    mul.s   ft5, ft4, fv0
+
+    swc1    ft2, 0(a0)
+    swc1    ft5, 4(a0)
+    addu    a0, a0, 8
+    addu    a1, a1, 4
+    bne     a1, t8, 1b
+
+    jr      ra
 END(guMtxL2F)
diff --git a/src/libultra/mgu/normalize.s b/src/libultra/mgu/normalize.s
index 7686317ea..da10204d6 100644
--- a/src/libultra/mgu/normalize.s
+++ b/src/libultra/mgu/normalize.s
@@ -1,31 +1,27 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noreorder
-
-.section .text
-
-.balign 32
+.text
+.align 5
 
 LEAF(guNormalize)
-    lwc1    $f4, ($a0)
-    lwc1    $f6, ($a1)
-    lwc1    $f8, ($a2)
-    mul.s   $f10, $f4, $f4
-    li      $t0, 0x3F800000 // 1.0f
-    mul.s   $f16, $f6, $f6
-    add.s   $f18, $f10, $f16
-    mul.s   $f16, $f8, $f8
-    add.s   $f10, $f16, $f18
-    mtc1    $t0, $f18
-    sqrt.s  $f16, $f10
-    div.s   $f10, $f18, $f16
-    mul.s   $f16, $f4, $f10
-    nop
-    mul.s   $f18, $f6, $f10
-    nop
-    mul.s   $f4, $f8, $f10
-    swc1    $f16, ($a0)
-    swc1    $f18, ($a1)
-    jr      $ra
-     swc1   $f4, ($a2)
+    lwc1    ft0, (a0)
+    lwc1    ft1, (a1)
+    lwc1    ft2, (a2)
+    li.s    t0, 1.0
+    mul.s   ft3, ft0, ft0
+    mul.s   ft4, ft1, ft1
+    add.s   ft5, ft3, ft4
+    mul.s   ft4, ft2, ft2
+    add.s   ft3, ft4, ft5
+    mtc1    t0, ft5
+    sqrt.s  ft4, ft3
+    div.s   ft3, ft5, ft4
+    mul.s   ft4, ft0, ft3
+    mul.s   ft5, ft1, ft3
+    mul.s   ft0, ft2, ft3
+    swc1    ft4, (a0)
+    swc1    ft5, (a1)
+    swc1    ft0, (a2)
+    jr      ra
 END(guNormalize)
diff --git a/src/libultra/mgu/scale.s b/src/libultra/mgu/scale.s
index 80199c062..5661b940c 100644
--- a/src/libultra/mgu/scale.s
+++ b/src/libultra/mgu/scale.s
@@ -1,52 +1,56 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
+.text
+.align 5
 
-.section .text
+LEAF(guScale)
+    li.s    ft0, 65536.0
 
-.balign 32
+    mtc1    a1, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t1, ft3
 
-LEAF(guScale)
-    li      $at, 0x47800000 // 65536.0f
-    mtc1    $at, $f4
-    mtc1    $a1, $f6
-    sw      $zero, 4($a0)
-    sw      $zero, 0xC($a0)
-    mul.s   $f8, $f6, $f4
-    mtc1    $a2, $f6
-    sw      $zero, 0x10($a0)
-    sw      $zero, 0x18($a0)
-    sw      $zero, 0x24($a0)
-    sw      $zero, 0x2C($a0)
-    sw      $zero, 0x30($a0)
-    trunc.w.s $f10, $f8
-    mul.s   $f8, $f6, $f4
-    mtc1    $a3, $f6
-    sw      $zero, 0x38($a0)
-    mfc1    $t1, $f10
-    sw      $zero, 0x3C($a0)
-    srl     $t2, $t1, 0x10
-    trunc.w.s $f10, $f8
-    mul.s   $f8, $f6, $f4
-    sll     $t0, $t2, 0x10
-    sll     $t2, $t1, 0x10
-    mfc1    $t1, $f10
-    sw      $t0, ($a0)
-    sw      $t2, 0x20($a0)
-    srl     $t0, $t1, 0x10
-    trunc.w.s $f10, $f8
-    andi    $t2, $t1, 0xFFFF
-    sw      $t2, 0x28($a0)
-    sw      $t0, 8($a0)
-    mfc1    $t1, $f10
-    nop
-    srl     $t2, $t1, 0x10
-    sll     $t0, $t2, 0x10
-    sw      $t0, 0x14($a0)
-    li      $t0, 1
-    sll     $t2, $t1, 0x10
-    sw      $t2, 0x34($a0)
-    jr      $ra
-     sw     $t0, 0x1C($a0)
+    srl     t2, t1, 0x10
+    sll     t0, t2, 0x10
+    sw      t0, 0x00(a0)
+    sll     t2, t1, 0x10
+    sw      t2, 0x20(a0)
+
+    mtc1    a2, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t1, ft3
+
+    srl     t0, t1, 0x10
+    sw      t0, 0x08(a0)
+    andi    t2, t1, 0xFFFF
+    sw      t2, 0x28(a0)
+
+    mtc1    a3, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t1, ft3
+
+    srl     t2, t1, 0x10
+    sll     t0, t2, 0x10
+    sw      t0, 0x14(a0)
+    sll     t2, t1, 0x10
+    sw      t2, 0x34(a0)
+
+    li      t0, 1
+    sw      t0, 0x1C(a0)
+
+    sw      zero, 0x04(a0)
+    sw      zero, 0x0C(a0)
+    sw      zero, 0x10(a0)
+    sw      zero, 0x18(a0)
+    sw      zero, 0x24(a0)
+    sw      zero, 0x2C(a0)
+    sw      zero, 0x30(a0)
+    sw      zero, 0x38(a0)
+    sw      zero, 0x3C(a0)
+
+    jr      ra
 END(guScale)
diff --git a/src/libultra/mgu/translate.s b/src/libultra/mgu/translate.s
index d059ad569..4ee630751 100644
--- a/src/libultra/mgu/translate.s
+++ b/src/libultra/mgu/translate.s
@@ -1,61 +1,68 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 
-.set noat
-.set noreorder
+.text
+.align 5
 
-.section .text
+LEAF(guTranslate)
+    li.s    ft0, 65536.0
 
-.balign 32
+    mtc1    a1, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t1, ft3
 
-LEAF(guTranslate)
-    li      $at, 0x47800000 // 65536.0f
-    mtc1    $at, $f4
-    mtc1    $a1, $f6
-    sw      $zero, ($a0)
-    sw      $zero, 0x14($a0)
-    mul.s   $f8, $f6, $f4
-    mtc1    $a2, $f6
-    sw      $zero, 8($a0)
-    sw      $zero, 4($a0)
-    sw      $zero, 0xC($a0)
-    sw      $zero, 0x10($a0)
-    sw      $zero, 0x20($a0)
-    trunc.w.s $f10, $f8
-    mul.s   $f8, $f6, $f4
-    mtc1    $a3, $f6
-    sw      $zero, 0x24($a0)
-    mfc1    $t1, $f10
-    sw      $zero, 0x28($a0)
-    sw      $zero, 0x2C($a0)
-    srl     $t2, $t1, 0x10
-    trunc.w.s $f10, $f8
-    mul.s   $f8, $f6, $f4
-    sll     $t0, $t2, 0x10
-    sw      $zero, 0x30($a0)
-    mfc1    $t3, $f10
-    sw      $zero, 0x34($a0)
-    srl     $t2, $t3, 0x10
-    trunc.w.s $f10, $f8
-    or      $t0, $t0, $t2
-    sw      $t0, 0x18($a0)
-    sll     $t0, $t1, 0x10
-    sll     $t2, $t3, 0x10
-    mfc1    $t1, $f10
-    srl     $t2, $t2, 0x10
-    or      $t0, $t0, $t2
-    sw      $t0, 0x38($a0)
-    srl     $t2, $t1, 0x10
-    sll     $t0, $t2, 0x10
-    addiu   $t0, $t0, 1
-    sw      $t0, 0x1C($a0)
-    lui     $t0, 1
-    ori     $t0, $t0, 0
-    sw      $t0, ($a0)
-    sw      $t0, 0x14($a0)
-    lui     $t0, (0x00000001 >> 16)
-    ori     $t0, (0x00000001 & 0xFFFF)
-    sll     $t2, $t1, 0x10
-    sw      $t2, 0x3C($a0)
-    jr      $ra
-     sw     $t0, 8($a0)
+    mtc1    a2, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t3, ft3
+
+    srl     t2, t1, 0x10
+    sll     t0, t2, 0x10
+    srl     t2, t3, 0x10
+    or      t0, t0, t2
+    sw      t0, 0x18(a0)
+
+    sll     t2, t3, 0x10
+    sll     t0, t1, 0x10
+    srl     t2, t2, 0x10
+    or      t0, t0, t2
+    sw      t0, 0x38(a0)
+
+    mtc1    a3, ft1
+    mul.s   ft2, ft1, ft0
+    trunc.w.s ft3, ft2
+    mfc1    t1, ft3
+
+    srl     t2, t1, 0x10
+    sll     t0, t2, 0x10
+    addiu   t0, t0, 1
+    sw      t0, 0x1C(a0)
+
+    sll     t2, t1, 0x10
+    sw      t2, 0x3C(a0)
+
+    sw      zero, 0x00(a0)
+    sw      zero, 0x04(a0)
+    sw      zero, 0x08(a0)
+    sw      zero, 0x0C(a0)
+    sw      zero, 0x10(a0)
+    sw      zero, 0x14(a0)
+    sw      zero, 0x20(a0)
+    sw      zero, 0x24(a0)
+    sw      zero, 0x28(a0)
+    sw      zero, 0x2C(a0)
+    sw      zero, 0x30(a0)
+    sw      zero, 0x34(a0)
+
+    lui     t0, (0x00010000 >> 16)
+    ori     t0, (0x00010000 & 0xFFFF)
+    sw      t0, (a0)
+    sw      t0, 0x14(a0)
+
+    lui     t0, (0x00000001 >> 16)
+    ori     t0, (0x00000001 & 0xFFFF)
+    sw      t0, 8(a0)
+
+    jr      ra
 END(guTranslate)
diff --git a/src/libultra/os/exceptasm.s b/src/libultra/os/exceptasm.s
index 3c55d66ac..3c02267b9 100644
--- a/src/libultra/os/exceptasm.s
+++ b/src/libultra/os/exceptasm.s
@@ -1,4 +1,8 @@
+#ifdef __GNUC__
+.set gp=64
+#endif
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 #include "ultra64/rcp.h"
 #include "ultra64/message.h"
@@ -6,17 +10,12 @@
 #include "ultra64/exception.h"
 #include "ultra64/version.h"
 
-.set noat
-.set noreorder
-.set gp=64
-
-.section .data
-
-.balign 16
+.data
+.align 2
 
 DATA(__osHwIntTable)
     .word 0, 0
-    .word 0, 0 // cart
+    .word 0, 0 /* cart */
     .word 0, 0
     .word 0, 0
     .word 0, 0
@@ -26,9 +25,8 @@ DATA(__osPiIntTable)
     .word 0, 0
 ENDDATA(__osPiIntTable)
 
-.section .rodata
-
-.balign 16
+.rdata
+.align 2
 
 __osIntOffTable:
     .byte 0x00 /* redispatch */
@@ -75,215 +73,197 @@ __osIntTable:
     .word IP7_Hdlr
     .word counter
 
-.section .text
-
-.balign 16
+.text
 
 /**
- * The exception preamble is copied to the exception vectors at
+ * The 16-byte exception preamble is copied to the exception vectors at
  * UT_VEC, XUT_VEC, ECC_VEC, E_VEC, to direct execution to __osException
  */
 LEAF(__osExceptionPreamble)
-    lui     $k0, %hi(__osException)
-    addiu   $k0, %lo(__osException)
-    jr      $k0
-     nop
+    la      k0, __osException
+    jr      k0
 END(__osExceptionPreamble)
 
 LEAF(__osException)
-    // Load scratch space for thread saving
-    lui     $k0, %hi(__osThreadSave)
-    addiu   $k0, %lo(__osThreadSave)
-    // Save $at
-    sd      $at, THREAD_AT($k0)
-    // Save sr
-    mfc0    $k1, C0_SR
-    sw      $k1, THREAD_SR($k0)
-    // Disable interrupts
-    li      $at, ~(SR_IE | SR_EXL)
-    and     $k1, $k1, $at
-    mtc0    $k1, C0_SR
-    // Save some temp registers for use in the following
-    sd      $t0, THREAD_T0($k0)
-    sd      $t1, THREAD_T1($k0)
-    sd      $t2, THREAD_T2($k0)
-    // Mark FPU as unused
-    sw      $zero, THREAD_FP($k0)
-    // Left over from misplaced ifdef, immediately overwritten on next instruction
-    mfc0    $t0, C0_CAUSE
+.set noat
+    /* Load scratch space for thread saving */
+    la      k0, __osThreadSave
+    /* Save at */
+    sd      AT, THREAD_AT(k0)
+.set at
+    /* Save sr */
+    MFC0(   k1, C0_SR)
+    sw      k1, THREAD_SR(k0)
+    /* Disable interrupts */
+    and     k1, k1, ~(SR_IE | SR_EXL)
+    MTC0(   k1, C0_SR)
+    /* Save some temp registers for use in the following */
+    sd      t0, THREAD_T0(k0)
+    sd      t1, THREAD_T1(k0)
+    sd      t2, THREAD_T2(k0)
+    /* Mark FPU as unused */
+    sw      zero, THREAD_FP(k0)
+    /* Left over from misplaced ifdef, immediately overwritten on next instruction */
+    MFC0(   t0, C0_CAUSE)
 savecontext:
-    // Save the previously running thread's context to be restored when it resumes
-    move    $t0, $k0
-    lui     $k0, %hi(__osRunningThread)
-    lw      $k0, %lo(__osRunningThread)($k0)
-    ld      $t1, THREAD_AT($t0)
-    sd      $t1, THREAD_AT($k0)
-    ld      $t1, THREAD_SR($t0)
-    sd      $t1, THREAD_SR($k0)
-    ld      $t1, THREAD_T0($t0)
-    sd      $t1, THREAD_T0($k0)
-    ld      $t1, THREAD_T1($t0)
-    sd      $t1, THREAD_T1($k0)
-    ld      $t1, THREAD_T2($t0)
-    sd      $t1, THREAD_T2($k0)
-    lw      $k1, THREAD_SR($k0)
-    mflo    $t0
-    sd      $t0, THREAD_LO($k0)
-    mfhi    $t0
-    andi    $t1, $k1, SR_IMASK
-    sd      $v0, THREAD_V0($k0)
-    sd      $v1, THREAD_V1($k0)
-    sd      $a0, THREAD_A0($k0)
-    sd      $a1, THREAD_A1($k0)
-    sd      $a2, THREAD_A2($k0)
-    sd      $a3, THREAD_A3($k0)
-    sd      $t3, THREAD_T3($k0)
-    sd      $t4, THREAD_T4($k0)
-    sd      $t5, THREAD_T5($k0)
-    sd      $t6, THREAD_T6($k0)
-    sd      $t7, THREAD_T7($k0)
-    sd      $s0, THREAD_S0($k0)
-    sd      $s1, THREAD_S1($k0)
-    sd      $s2, THREAD_S2($k0)
-    sd      $s3, THREAD_S3($k0)
-    sd      $s4, THREAD_S4($k0)
-    sd      $s5, THREAD_S5($k0)
-    sd      $s6, THREAD_S6($k0)
-    sd      $s7, THREAD_S7($k0)
-    sd      $t8, THREAD_T8($k0)
-    sd      $t9, THREAD_T9($k0)
-    sd      $gp, THREAD_GP($k0)
-    sd      $sp, THREAD_SP($k0)
-    sd      $fp, THREAD_S8($k0)
-    sd      $ra, THREAD_RA($k0)
-    beqz    $t1, savercp
-     sd     $t0, THREAD_HI($k0)
-    // If any CPU interrupts are enabled in the previous thread's SR, bitwise-OR in the
-    // disabled CPU interrupts from the global interrupt mask.
-    // This is an attempt at reverting the effect of masking the thread's SR with the
-    // global interrupt mask. This is however broken, see comments for osSetIntMask.
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, ($t0)
-    li      $at, ~0
-    xor     $t2, $t0, $at
-    lui     $at, ((~SR_IMASK) >> 0x10) & 0xFFFF
-    andi    $t2, $t2, SR_IMASK
-    ori     $at, (~SR_IMASK) & 0xFFFF
-    or      $t4, $t1, $t2
-    and     $t3, $k1, $at
-    andi    $t0, $t0, SR_IMASK
-    or      $t3, $t3, $t4
-    and     $t1, $t1, $t0
-    and     $k1, $k1, $at
-    sw      $t3, THREAD_SR($k0)
-    or      $k1, $k1, $t1
+.set noreorder
+    /* Save the previously running thread's context to be restored when it resumes */
+    move    t0, k0
+    lw      k0, __osRunningThread
+    ld      t1, THREAD_AT(t0)
+    sd      t1, THREAD_AT(k0)
+    ld      t1, THREAD_SR(t0)
+    sd      t1, THREAD_SR(k0)
+    ld      t1, THREAD_T0(t0)
+    sd      t1, THREAD_T0(k0)
+    ld      t1, THREAD_T1(t0)
+    sd      t1, THREAD_T1(k0)
+    ld      t1, THREAD_T2(t0)
+    sd      t1, THREAD_T2(k0)
+.set reorder
+    sd      $2, THREAD_V0(k0)
+    sd      $3, THREAD_V1(k0)
+    sd      $4, THREAD_A0(k0)
+    sd      $5, THREAD_A1(k0)
+    sd      $6, THREAD_A2(k0)
+    sd      $7, THREAD_A3(k0)
+    sd      $11, THREAD_T3(k0)
+    sd      $12, THREAD_T4(k0)
+    sd      $13, THREAD_T5(k0)
+    sd      $14, THREAD_T6(k0)
+    sd      $15, THREAD_T7(k0)
+    sd      $16, THREAD_S0(k0)
+    sd      $17, THREAD_S1(k0)
+    sd      $18, THREAD_S2(k0)
+    sd      $19, THREAD_S3(k0)
+    sd      $20, THREAD_S4(k0)
+    sd      $21, THREAD_S5(k0)
+    sd      $22, THREAD_S6(k0)
+    sd      $23, THREAD_S7(k0)
+    sd      $24, THREAD_T8(k0)
+    sd      $25, THREAD_T9(k0)
+    sd      $28, THREAD_GP(k0)
+    sd      $29, THREAD_SP(k0)
+    sd      $30, THREAD_S8(k0)
+    sd      $31, THREAD_RA(k0)
+    mflo    t0
+    sd      t0, THREAD_LO(k0)
+    mfhi    t0
+    sd      t0, THREAD_HI(k0)
+    lw      k1, THREAD_SR(k0)
+    andi    t1, k1, SR_IMASK
+    beqz    t1, savercp
+    /* If any CPU interrupts are enabled in the previous thread's SR, bitwise-OR in the */
+    /* disabled CPU interrupts from the global interrupt mask. */
+    /* This is an attempt at reverting the effect of masking the thread's SR with the */
+    /* global interrupt mask. This is however broken, see comments for osSetIntMask. */
+    la      t0, __OSGlobalIntMask
+    lw      t0, (t0)
+    xor     t2, t0, ~0
+    andi    t2, t2, SR_IMASK
+    or      t4, t1, t2
+    and     t3, k1, ~SR_IMASK
+    andi    t0, t0, SR_IMASK
+    or      t3, t3, t4
+    and     t1, t1, t0
+    and     k1, k1, ~SR_IMASK
+    sw      t3, THREAD_SR(k0)
+    or      k1, k1, t1
 savercp:
-    // Save the currently masked RCP interrupts.
-    lui     $t1, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    lw      $t1, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))($t1)
-    beqz    $t1, endrcp
-     nop
-    // Similar to the above comment, but for RCP interrupt enable bits rather than CPU.
-    // This suffers from the same problem as above.
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, ($t0)
-    lw      $t4, THREAD_RCP($k0)
-    li      $at, ~0
-    srl     $t0, $t0, RCP_IMASKSHIFT
-    xor     $t0, $t0, $at
-    andi    $t0, $t0, (RCP_IMASK >> RCP_IMASKSHIFT)
-    and     $t0, $t0, $t4
-    or      $t1, $t1, $t0
+    /* Save the currently masked RCP interrupts. */
+    lw      t1, PHYS_TO_K1(MI_INTR_MASK_REG)
+    beqz    t1, endrcp
+    /* Similar to the above comment, but for RCP interrupt enable bits rather than CPU. */
+    /* This suffers from the same problem as above. */
+    la      t0, __OSGlobalIntMask
+    lw      t0, (t0)
+    srl     t0, t0, RCP_IMASKSHIFT
+    xor     t0, t0, ~0
+    andi    t0, t0, (RCP_IMASK >> RCP_IMASKSHIFT)
+    lw      t4, THREAD_RCP(k0)
+    and     t0, t0, t4
+    or      t1, t1, t0
 endrcp:
-    sw      $t1, THREAD_RCP($k0)
-    mfc0    $t0, C0_EPC
-    sw      $t0, THREAD_PC($k0)
-    lw      $t0, THREAD_FP($k0)
-    beqz    $t0, handle_interrupt
-     nop
-    // Save FP Registers if FPU was used by the thread
-    cfc1    $t0, C1_FPCSR
+    sw      t1, THREAD_RCP(k0)
+    MFC0(   t0, C0_EPC)
+    sw      t0, THREAD_PC(k0)
+    lw      t0, THREAD_FP(k0)
+    beqz    t0, handle_interrupt
+    /* Save FP Registers if FPU was used by the thread */
+.set noreorder 
+    cfc1    t0, C1_FPCSR
     nop
-    sw      $t0, THREAD_FPCSR($k0)
-    sdc1    $f0, THREAD_FP0($k0)
-    sdc1    $f2, THREAD_FP2($k0)
-    sdc1    $f4, THREAD_FP4($k0)
-    sdc1    $f6, THREAD_FP6($k0)
-    sdc1    $f8, THREAD_FP8($k0)
-    sdc1    $f10, THREAD_FP10($k0)
-    sdc1    $f12, THREAD_FP12($k0)
-    sdc1    $f14, THREAD_FP14($k0)
-    sdc1    $f16, THREAD_FP16($k0)
-    sdc1    $f18, THREAD_FP18($k0)
-    sdc1    $f20, THREAD_FP20($k0)
-    sdc1    $f22, THREAD_FP22($k0)
-    sdc1    $f24, THREAD_FP24($k0)
-    sdc1    $f26, THREAD_FP26($k0)
-    sdc1    $f28, THREAD_FP28($k0)
-    sdc1    $f30, THREAD_FP30($k0)
+    sw      t0, THREAD_FPCSR(k0)
+.set reorder
+    sdc1    $f0, THREAD_FP0(k0)
+    sdc1    $f2, THREAD_FP2(k0)
+    sdc1    $f4, THREAD_FP4(k0)
+    sdc1    $f6, THREAD_FP6(k0)
+    sdc1    $f8, THREAD_FP8(k0)
+    sdc1    $f10, THREAD_FP10(k0)
+    sdc1    $f12, THREAD_FP12(k0)
+    sdc1    $f14, THREAD_FP14(k0)
+    sdc1    $f16, THREAD_FP16(k0)
+    sdc1    $f18, THREAD_FP18(k0)
+    sdc1    $f20, THREAD_FP20(k0)
+    sdc1    $f22, THREAD_FP22(k0)
+    sdc1    $f24, THREAD_FP24(k0)
+    sdc1    $f26, THREAD_FP26(k0)
+    sdc1    $f28, THREAD_FP28(k0)
+    sdc1    $f30, THREAD_FP30(k0)
 
 handle_interrupt:
-    // Determine the cause of the exception or interrupt and
-    // enter appropriate handling routine
-    mfc0    $t0, C0_CAUSE
-    sw      $t0, THREAD_CAUSE($k0)
-    li      $t1, OS_STATE_RUNNABLE
-    sh      $t1, THREAD_STATE($k0)
-    andi    $t1, $t0, CAUSE_EXCMASK
-    // Test for break exception
-    li      $t2, EXC_BREAK
-    beq     $t1, $t2, handle_break
-     nop
-    // Test for CpU (coprocessor unusable) exception
-    li      $t2, EXC_CPU
-    beq     $t1, $t2, handle_CpU
-     nop
-    // Test for interrupt, if it's not an interrupt, panic
-    li      $t2, EXC_INT
-    bne     $t1, $t2, panic
-     nop
-    and     $s0, $k1, $t0
+    /* Determine the cause of the exception or interrupt and */
+    /* enter appropriate handling routine */
+    MFC0(   t0, C0_CAUSE)
+    sw      t0, THREAD_CAUSE(k0)
+label:
+    li      t1, OS_STATE_RUNNABLE
+    sh      t1, THREAD_STATE(k0)
+    andi    t1, t0, CAUSE_EXCMASK
+    /* Test for break exception */
+    li      t2, EXC_BREAK
+    beq     t1, t2, handle_break
+    /* Test for CpU (coprocessor unusable) exception */
+    li      t2, EXC_CPU
+    beq     t1, t2, handle_CpU
+    /* Test for interrupt, if it's not an interrupt, panic */
+    li      t2, EXC_INT
+    bne     t1, t2, panic
+
+    and     s0, k1, t0
 
 next_interrupt:
-    // Handle external interrupt causes, using a jump table
-    // to enter into the appropriate handler
-    andi    $t1, $s0, CAUSE_IPMASK
-    srl     $t2, $t1, CAUSE_IPSHIFT + 4
-    bnez    $t2, 1f
-     nop
-    srl     $t2, $t1, CAUSE_IPSHIFT
-    addi    $t2, $t2, 0x10
+    /* Handle external interrupt causes, using a jump table */
+    /* to enter into the appropriate handler */
+    andi    t1, s0, CAUSE_IPMASK
+    srl     t2, t1, CAUSE_IPSHIFT + 4
+    bnez    t2, 1f
+
+    srl     t2, t1, CAUSE_IPSHIFT
+    addi    t2, t2, 0x10
 1:
-    lui     $at, %hi(__osIntOffTable)
-    addu    $at, $at, $t2
-    lbu     $t2, %lo(__osIntOffTable)($at)
-    lui     $at, %hi(__osIntTable)
-    addu    $at, $at, $t2
-    lw      $t2, %lo(__osIntTable)($at)
-    jr      $t2
-     nop
+    lbu     t2, __osIntOffTable(t2)
+    lw      t2, __osIntTable(t2)
+    jr      t2
 
 /**
  *  IP6 Interrupt
  *  Only signalled by development hardware
  */
 IP6_Hdlr:
-    // Mask out interrupt and continue
-    li      $at, ~CAUSE_IP6
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_IP6
     b       next_interrupt
-     and    $s0, $s0, $at
 
 /**
  *  IP7 Interrupt
  *  Only signalled by development hardware
  */
 IP7_Hdlr:
-    // Mask out interrupt and continue
-    li      $at, ~CAUSE_IP7
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_IP7
     b       next_interrupt
-     and    $s0, $s0, $at
 
 /**
  *  IP8/Counter Interrupt
@@ -291,435 +271,368 @@ IP7_Hdlr:
  *  cop0 compare register, this interrupt is triggered
  */
 counter:
-    mfc0    $t1, C0_COMPARE
-    mtc0    $t1, C0_COMPARE
-    // Post counter message
+    MFC0(   t1, C0_COMPARE)
+    MTC0(   t1, C0_COMPARE)
+    /* Post counter message */
+    li      a0, OS_EVENT_COUNTER*8
     jal     send_mesg
-     li     $a0, OS_EVENT_COUNTER*8
-    // Mask out interrupt and continue
-    li      $at, ~CAUSE_IP8
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_IP8
     b       next_interrupt
-     and    $s0, $s0, $at
 
 /**
  *  IP4/Cartridge Interrupt
  *  Signalled by the N64 Disk Drive
  */
 cart:
-    // Load cart callback set by __osSetHWIntrRoutine
-    lui     $t1, %hi(__osHwIntTable)
-    addiu   $t1, %lo(__osHwIntTable)
-    lw      $t2, (OS_INTR_CART*HWINT_SIZE+HWINT_CALLBACK)($t1)
-    // Mask out interrupt
-    li      $at, ~CAUSE_IP4
-    and     $s0, $s0, $at
-    // If the callback is NULL, handling is done
-    beqz    $t2, send_cart_mesg
-     addi   $t1, $t1, (OS_INTR_CART*HWINT_SIZE)
-    // Set up a stack and run the callback
-    jalr    $t2
-     lw     $sp, HWINT_SP($t1)
-    beqz    $v0, send_cart_mesg
-     nop
-    // Redispatch immediately if the callback returned nonzero
+    /* Load cart callback set by __osSetHWIntrRoutine */
+    la      t1, __osHwIntTable
+    lw      t2, (OS_INTR_CART*HWINT_SIZE+HWINT_CALLBACK)(t1)
+    /* Mask out interrupt */
+    and     s0, s0, ~CAUSE_IP4
+    /* If the callback is NULL, handling is done */
+    addi    t1, t1, (OS_INTR_CART*HWINT_SIZE)
+    beqz    t2, send_cart_mesg
+    /* Set up a stack and run the callback */
+    lw      sp, HWINT_SP(t1)
+    jalr    t2
+    beqz    v0, send_cart_mesg
+    /* Redispatch immediately if the callback returned nonzero */
     b       redispatch
-     nop
 send_cart_mesg:
-    // Post a cart event message
+    /* Post a cart event message */
+    li      a0, OS_EVENT_CART*8
     jal     send_mesg
-     li     $a0, OS_EVENT_CART*8
-    // Continue
+    /* Continue */
     b       next_interrupt
-     nop
 
 /**
  *  IP3/RCP Interrupt
  *  Signalled by the RCP for various reasons, described below
  */
 rcp:
-    // Load the MI interrupts and mask with the RCP bits in the global interrupt mask
-    //! @bug this clobbers the t0 register which is expected to hold the value of the
-    //! C0_CAUSE register in the sw1 and sw2 handlers. If the sw1 or sw2 handler runs
-    //! after this, the interrupt will not be cleared properly.
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, ($t0)
-    lui     $s1, %hi(PHYS_TO_K1(MI_INTR_REG))
-    lw      $s1, %lo(PHYS_TO_K1(MI_INTR_REG))($s1)
-    srl     $t0, $t0, RCP_IMASKSHIFT
-    and     $s1, $s1, $t0
+    /* Load the MI interrupts and mask with the RCP bits in the global interrupt mask */
+    /*! @bug this clobbers the t0 register which is expected to hold the value of the */
+    /*! C0_CAUSE register in the sw1 and sw2 handlers. If the sw1 or sw2 handler runs */
+    /*! after this, the interrupt will not be cleared properly. */
+    la      t0, __OSGlobalIntMask
+    lw      t0, (t0)
+    srl     t0, t0, RCP_IMASKSHIFT
+    lw      s1, PHYS_TO_K1(MI_INTR_REG)
+    and     s1, s1, t0
 
 /**
  *  Signal Processor (SP) Interrupt
  */
-sp:
-    // Test for sp interrupt
-    andi    $t1, $s1, MI_INTR_SP
-    beqz    $t1, vi
-     nop
-    // Test for yielded or done signals in particular
-    lui     $t4, %hi(PHYS_TO_K1(SP_STATUS_REG))
-    lw      $t4, %lo(PHYS_TO_K1(SP_STATUS_REG))($t4)
-    li      $t1, (SP_CLR_INTR | SP_CLR_SIG3)
-    lui     $at, %hi(PHYS_TO_K1(SP_STATUS_REG))
-    andi    $t4, $t4, (SP_STATUS_YIELDED | SP_STATUS_TASKDONE)
-    // Mask out SP interrupt
-    andi    $s1, $s1, (MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
-    beqz    $t4, sp_other_break
-    // Clear interrupt and signal 3
-     sw     $t1, %lo(PHYS_TO_K1(SP_STATUS_REG))($at)
-    // Post an SP event message
+    /* Test for sp interrupt */
+    andi    t1, s1, MI_INTR_SP
+    beqz    t1, vi
+    /* Test for yielded or done signals in particular */
+    lw      t4, PHYS_TO_K1(SP_STATUS_REG)
+    li      t1, (SP_CLR_INTR | SP_CLR_SIG3)
+    andi    t4, t4, (SP_STATUS_YIELDED | SP_STATUS_TASKDONE)
+    /* Mask out SP interrupt */
+    andi    s1, s1, (MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
+    sw      t1, PHYS_TO_K1(SP_STATUS_REG)
+    beqz    t4, sp_other_break
+    /* Clear interrupt and signal 3 */
+    /* Post an SP event message */
+    li      a0, OS_EVENT_SP*8
     jal     send_mesg
-     li     $a0, OS_EVENT_SP*8
-    beqz    $s1, NoMoreRcpInts
-     nop
-    // Step over sp_other_break handler
+    beqz    s1, NoMoreRcpInts
+    /* Step over sp_other_break handler */
     b       vi
-     nop
 
 sp_other_break:
-    // An sp signal that is not due to yielding or task completion, such as
-    // an sp breakpoint. Post a different event message
+    /* An sp signal that is not due to yielding or task completion, such as */
+    /* an sp breakpoint. Post a different event message */
+    li      a0, OS_EVENT_SP_BREAK*8
     jal     send_mesg
-     li     $a0, OS_EVENT_SP_BREAK*8
-    beqz    $s1, NoMoreRcpInts
-     nop
+    beqz    s1, NoMoreRcpInts
 
 /**
  *  Video Interface (VI) Interrupt
  */
 vi:
-    // Test for vi interrupt
-    andi    $t1, $s1, MI_INTR_VI
-    beqz    $t1, ai
-     lui    $at, %hi(PHYS_TO_K1(VI_CURRENT_REG))
-    // Mask out vi interrupt
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_PI | MI_INTR_DP)
-    // Clear interrupt
-    sw      $zero, %lo(PHYS_TO_K1(VI_CURRENT_REG))($at)
-    // Post vi event message
+    /* Test for vi interrupt */
+    andi    t1, s1, MI_INTR_VI
+    beqz    t1, ai
+    /* Mask out vi interrupt */
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_PI | MI_INTR_DP)
+    /* Clear interrupt */
+    sw      zero, PHYS_TO_K1(VI_CURRENT_REG)
+    /* Post vi event message */
+    li      a0, OS_EVENT_VI*8
     jal     send_mesg
-     li     $a0, OS_EVENT_VI*8
-    beqz    $s1, NoMoreRcpInts
-     nop
+    beqz    s1, NoMoreRcpInts
 
 /**
  *  Audio Interface (AI) Interrupt
  */
 ai:
-    // Test for ai interrupt
-    andi    $t1, $s1, MI_INTR_AI
-    beqz    $t1, si
-     nop
-    li      $t1, 1
-    lui     $at, %hi(PHYS_TO_K1(AI_STATUS_REG))
-    // Mask out ai interrupt
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
-    // Clear interrupt
-    sw      $t1, %lo(PHYS_TO_K1(AI_STATUS_REG))($at)
-    // Post ai event message
+    /* Test for ai interrupt */
+    andi    t1, s1, MI_INTR_AI
+    beqz    t1, si
+
+    /* Mask out ai interrupt */
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
+    /* Clear interrupt */
+    li      t1, 1
+    sw      t1, PHYS_TO_K1(AI_STATUS_REG)
+    /* Post ai event message */
+    li      a0, OS_EVENT_AI*8
     jal     send_mesg
-     li     $a0, OS_EVENT_AI*8
-    beqz    $s1, NoMoreRcpInts
-     nop
+    beqz    s1, NoMoreRcpInts
 
 /**
  *  Serial Interface (SI) Interrupt
  */
 si:
-    // Test for si interrupt
-    andi    $t1, $s1, MI_INTR_SI
-    beqz    $t1, pi
-     lui    $at, %hi(PHYS_TO_K1(SI_STATUS_REG))
-    // Mask out si interrupt
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
-    // Clear interrupt
-    sw      $zero, %lo(PHYS_TO_K1(SI_STATUS_REG))($at)
-    // Post si event message
+    /* Test for si interrupt */
+    andi    t1, s1, MI_INTR_SI
+    beqz    t1, pi
+
+    /* Mask out si interrupt */
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI | MI_INTR_DP)
+    /* Clear interrupt */
+    sw      zero, PHYS_TO_K1(SI_STATUS_REG)
+    /* Post si event message */
+    li      a0, OS_EVENT_SI*8
     jal     send_mesg
-     li     $a0, OS_EVENT_SI*8
-    beqz    $s1, NoMoreRcpInts
-     nop
+    beqz    s1, NoMoreRcpInts
 
 /**
  *  Parallel Interface (PI) Interrupt
  */
 pi:
-    // Test for pi interrupt
-    andi    $t1, $s1, MI_INTR_PI
-    beqz    $t1, dp
-     nop
+    /* Test for pi interrupt */
+    andi    t1, s1, MI_INTR_PI
+    beqz    t1, dp
+
+    /* Clear and mask the interrupt */
 #if LIBULTRA_VERSION < LIBULTRA_VERSION_J
-    // Clear interrupt and mask out pi interrupt
-    li      $t1, PI_STATUS_CLR_INTR
-    lui     $at, %hi(PHYS_TO_K1(PI_STATUS_REG))
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_DP)
-    sw      $t1, %lo(PHYS_TO_K1(PI_STATUS_REG))($at)
+    li      t1, PI_STATUS_CLR_INTR
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_DP)
+    sw      t1, PHYS_TO_K1(PI_STATUS_REG)
 #else
-    // Clear interrupt
-    li      $t1, PI_STATUS_CLR_INTR
-    lui     $at, %hi(PHYS_TO_K1(PI_STATUS_REG))
-    sw      $t1, %lo(PHYS_TO_K1(PI_STATUS_REG))($at)
-    // Load pi callback
-    lui     $t1, %hi(__osPiIntTable)
-    addiu   $t1, %lo(__osPiIntTable)
-    lw      $t2, HWINT_CALLBACK($t1)
-    // Mask out pi interrupt
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_DP)
-    // Skip callback if NULL
-    beqz    $t2, no_pi_callback
-     nop
-    // Set up a stack and run the callback
-    lw      $sp, HWINT_SP($t1)
-    jalr    $t2
-     move   $a0, $v0
-    // If the callback returns non-zero, don't post a pi event message
-    bnez    $v0, skip_pi_mesg
-     nop
+    /* Clear the interrupt */
+    li      t1, PI_STATUS_CLR_INTR
+    sw      t1, PHYS_TO_K1(PI_STATUS_REG)
+    /* Load pi callback */
+    la      t1, __osPiIntTable
+    lw      t2, HWINT_CALLBACK(t1)
+    /* Mask out pi interrupt */
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_DP)
+    /* Skip callback if NULL */
+    beqz    t2, no_pi_callback
+    /* Set up a stack and run the callback */
+    lw      sp, HWINT_SP(t1)
+    move    a0, v0
+    jalr    t2
+    /* If the callback returns non-zero, don't post a pi event message */
+    bnez    v0, skip_pi_mesg
 #endif
 no_pi_callback:
-    // Post pi event message
+    /* Post pi event message */
+    li      a0, OS_EVENT_PI*8
     jal     send_mesg
-     li     $a0, OS_EVENT_PI*8
 skip_pi_mesg:
-    beqz    $s1, NoMoreRcpInts
-     nop
+    beqz    s1, NoMoreRcpInts
 
 /**
  *  Display Processor (DP) Interrupt
  */
 dp:
-    // Test for dp interrupt
-    andi    $t1, $s1, MI_INTR_DP
-    beqz    $t1, NoMoreRcpInts
-     nop
-    // Clear dp interrupt
-    li      $t1, MI_CLR_DP_INTR
-    lui     $at, %hi(PHYS_TO_K1(MI_INIT_MODE_REG))
-    // Mask out dp interrupt
-    andi    $s1, $s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI)
-    sw      $t1, %lo(PHYS_TO_K1(MI_INIT_MODE_REG))($at)
-    // Post dp event message
+    /* Test for dp interrupt */
+    andi    t1, s1, MI_INTR_DP
+    beqz    t1, NoMoreRcpInts
+
+    /* Mask out dp interrupt */
+    andi    s1, s1, (MI_INTR_SP | MI_INTR_SI | MI_INTR_AI | MI_INTR_VI | MI_INTR_PI)
+    /* Clear dp interrupt */
+    li      t1, MI_CLR_DP_INTR
+    sw      t1, PHYS_TO_K1(MI_INIT_MODE_REG)
+    /* Post dp event message */
+    li      a0, OS_EVENT_DP*8
     jal     send_mesg
-     li     $a0, OS_EVENT_DP*8
 
 NoMoreRcpInts:
-    // Mask out interrupt and continue
-    li      $at, ~CAUSE_IP3
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_IP3
     b       next_interrupt
-     and    $s0, $s0, $at
 
 /**
  *  IP5/PreNMI Interrupt
  *  Reset button has been pressed
  */
 prenmi:
-    // Disable IP5/PreNMI interrupt for the previously running thread
-    lw      $k1, THREAD_SR($k0)
-    li      $at, ~SR_IBIT5
-    lui     $t1, %hi(__osShutdown)
-    and     $k1, $k1, $at
-    sw      $k1, THREAD_SR($k0)
-    addiu   $t1, %lo(__osShutdown)
-    // Test __osShutdown for first PreNMI event
-    lw      $t2, ($t1)
-    beqz    $t2, firstnmi
-     li     $at, ~CAUSE_IP5
-    // Mask out interrupt and redispatch immediately
+    /* Disable IP5/PreNMI interrupt for the previously running thread */
+    lw      k1, THREAD_SR(k0)
+    and     k1, k1, ~SR_IBIT5
+    sw      k1, THREAD_SR(k0)
+    /* Test __osShutdown for first PreNMI event */
+    la      t1, __osShutdown
+    lw      t2, (t1)
+    beqz    t2, firstnmi
+    /* Mask out interrupt and redispatch immediately */
+    and     s0, s0, ~CAUSE_IP5
     b       redispatch
-     and    $s0, $s0, $at
 
 firstnmi:
-    // Set __osShutdown
-    li      $t2, 1
-    sw      $t2, ($t1)
-    // Post a PreNMI event message
+    /* Set __osShutdown */
+    li      t2, 1
+    sw      t2, (t1)
+    /* Post a PreNMI event message */
+    li      a0, OS_EVENT_PRENMI*8
     jal     send_mesg
-     li     $a0, OS_EVENT_PRENMI*8
-    // Mask out and disable IP5/PreNMI interrupt for the highest priority thread
-    lui     $t2, %hi(__osRunQueue)
-    lw      $t2, %lo(__osRunQueue)($t2)
-    li      $at, ~SR_IBIT5
-    and     $s0, $s0, $at
-    lw      $k1, THREAD_SR($t2)
-    and     $k1, $k1, $at
-    // Redispatch immediately
+    /* Mask out and disable IP5/PreNMI interrupt for the highest priority thread */
+    lw      t2, __osRunQueue
+    and     s0, s0, ~SR_IBIT5
+    lw      k1, THREAD_SR(t2)
+    and     k1, k1, ~SR_IBIT5
+    sw      k1, THREAD_SR(t2)
+    /* Redispatch immediately */
     b       redispatch
-     sw     $k1, THREAD_SR($t2)
 
 sw2:
-    // Mask out interrupt
-    li      $at, ~CAUSE_SW2
-    and     $t0, $t0, $at
-    mtc0    $t0, C0_CAUSE
-    // Post sw2 event message
+    /* Mask out interrupt */
+    and     t0, t0, ~CAUSE_SW2
+    MTC0(   t0, C0_CAUSE)
+    /* Post sw2 event message */
+    li      a0, OS_EVENT_SW2*8
     jal     send_mesg
-     li     $a0, OS_EVENT_SW2*8
-    li      $at, ~CAUSE_SW2
-    // Mask out interrupt and continue
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_SW2
     b       next_interrupt
-     and    $s0, $s0, $at
 
 sw1:
-    // Mask out interrupt
-    li      $at, ~CAUSE_SW1
-    and     $t0, $t0, $at
-    mtc0    $t0, C0_CAUSE
-    // Post sw1 event message
+    /* Mask out interrupt */
+    and     t0, t0, ~CAUSE_SW1
+    MTC0(   t0, C0_CAUSE)
+    /* Post sw1 event message */
+    li      a0, OS_EVENT_SW1*8
     jal     send_mesg
-     li     $a0, OS_EVENT_SW1*8
-    li      $at, ~CAUSE_SW1
-    // Mask out interrupt and continue
+    /* Mask out interrupt and continue */
+    and     s0, s0, ~CAUSE_SW1
     b       next_interrupt
-     and    $s0, $s0, $at
 
 handle_break:
-    // Set last thread as having hit a break exception
-    li      $t1, OS_FLAG_CPU_BREAK
-    sh      $t1, THREAD_FLAGS($k0)
-    // Post a cpu break event message
+    /* Set last thread as having hit a break exception */
+    li      t1, OS_FLAG_CPU_BREAK
+    sh      t1, THREAD_FLAGS(k0)
+    /* Post a cpu break event message */
+    li      a0, OS_EVENT_CPU_BREAK*8
     jal     send_mesg
-     li     $a0, OS_EVENT_CPU_BREAK*8
-    // Redispatch
+    /* Redispatch */
     b       redispatch
-     nop
 
 redispatch:
-    lui     $t2, %hi(__osRunQueue)
-    lw      $t2, %lo(__osRunQueue)($t2)
-    // Get priority of previously running thread
-    lw      $t1, THREAD_PRI($k0)
-    // Get highest priority from waiting threads
-    lw      $t3, THREAD_PRI($t2)
-    slt     $at, $t1, $t3
-    beqz    $at, enqueueRunning
-     nop
-    // The previously running thread is no longer the highest priority,
-    //  enqueue it to the run queue to wait its turn again
-    lui     $a0, %hi(__osRunQueue)
-    move    $a1, $k0
+    lw      t2, __osRunQueue
+    /* Get priority of previously running thread */
+    lw      t1, THREAD_PRI(k0)
+    /* Get highest priority from waiting threads */
+    lw      t3, THREAD_PRI(t2)
+    bge     t1, t3, enqueueRunning
+    /* The previously running thread is no longer the highest priority, */
+    /*  enqueue it to the run queue to wait its turn again */
+    move    a1, k0
+    la      a0, __osRunQueue
     jal     __osEnqueueThread
-     addiu  $a0, $a0, %lo(__osRunQueue)
+
     j       __osDispatchThread
-     nop
 
 /**
  *  Resume the previously running thread by placing it at the top of
  *  the run queue and dispatching it
  */
 enqueueRunning:
-    lui     $t1, %hi(__osRunQueue)
-    addiu   $t1, $t1, %lo(__osRunQueue)
-    lw      $t2, ($t1)
-    sw      $t2, THREAD_NEXT($k0)
+    la      t1, __osRunQueue
+    lw      t2, (t1)
+    sw      t2, THREAD_NEXT(k0)
+    sw      k0, (t1)
     j       __osDispatchThread
-     sw     $k0, ($t1)
 
 /**
  *  Unhandled exceptions & interrupts end up here,
  *  trap to software by posting a fault message
  */
 panic:
-    // Mark the thread as having faulted
-    lui     $at, %hi(__osFaultedThread)
-    sw      $k0, %lo(__osFaultedThread)($at)
-    li      $t1, OS_STATE_STOPPED
-    sh      $t1, THREAD_STATE($k0)
-    li      $t1, OS_FLAG_FAULT
-    sh      $t1, THREAD_FLAGS($k0)
-    // Save C0_BADVADDR
-    mfc0    $t2, C0_BADVADDR
-    sw      $t2, THREAD_BADVADDR($k0)
-    // Post the fault message
+    /* Mark the thread as having faulted */
+    sw      k0, __osFaultedThread
+    li      t1, OS_STATE_STOPPED
+    sh      t1, THREAD_STATE(k0)
+    li      t1, OS_FLAG_FAULT
+    sh      t1, THREAD_FLAGS(k0)
+    /* Save C0_BADVADDR */
+    MFC0(   t2, C0_BADVADDR)
+    sw      t2, THREAD_BADVADDR(k0)
+    /* Post the fault message */
+    li      a0, OS_EVENT_FAULT*8
     jal     send_mesg
-     li     $a0, OS_EVENT_FAULT*8
-    // Dispatch next thread
+    /* Dispatch next thread */
     j       __osDispatchThread
-     nop
 
 /**
  *  Handles posting event messages to the listening message queue, if there is one
  */
 send_mesg:
-    // Load pointer to listening message queue
-    lui     $t2, %hi(__osEventStateTab)
-    addiu   $t2, %lo(__osEventStateTab)
-    addu    $t2, $t2, $a0
-    lw      $t1, ($t2)
-    // Save return address
-    move    $s2, $ra
-    // If there is no listening message queue, done
-    beqz    $t1, send_done
-     nop
-    // Test if the message queue is full, if so don't post the message
-    lw      $t3, MQ_VALIDCOUNT($t1)
-    lw      $t4, MQ_MSGCOUNT($t1)
-    slt     $at, $t3, $t4
-    beqz    $at, send_done
-     nop
-    // Add validcount to first and modulo with msgcount
-    lw      $t5, MQ_FIRST($t1)
-    addu    $t5, $t5, $t3
-    // Modulo
-    div     $zero, $t5, $t4
-    bnez    $t4, 1f
-     nop
-    break   7 // div0
-1:
-    li      $at, -1
-    bne     $t4, $at, 2f
-     li     $at, -0x80000000
-    bne     $t5, $at, 2f
-     nop
-    break   6 // overflow
-2:
-    // End Modulo
-    lw      $t4, MQ_MSG($t1)
-    mfhi    $t5
-    sll     $t5, $t5, 2
-    addu    $t4, $t4, $t5
-    // Fetch the message to post
-    lw      $t5, 4($t2)
-    addiu   $t2, $t3, 1
-    // Post the message to the message queue
-    sw      $t5, ($t4)
-    // Increment the validCount
-    sw      $t2, MQ_VALIDCOUNT($t1)
-    // If there was a thread blocked on this message queue,
-    //  wake it up
-    lw      $t2, MQ_MTQUEUE($t1)
-    lw      $t3, ($t2)
-    beqz    $t3, send_done
-     nop
+    /* Load pointer to listening message queue */
+    la      t2, __osEventStateTab
+    addu    t2, t2, a0
+    lw      t1, (t2)
+    /* Save return address */
+    move    s2, ra
+    /* If there is no listening message queue, done */
+    beqz    t1, send_done
+
+    /* Test if the message queue is full, if so don't post the message */
+    lw      t3, MQ_VALIDCOUNT(t1)
+    lw      t4, MQ_MSGCOUNT(t1)
+    bge     t3, t4, send_done
+
+    /* Add validcount to first and modulo with msgcount */
+    lw      t5, MQ_FIRST(t1)
+    addu    t5, t5, t3
+    rem     t5, t5, t4
+    lw      t4, MQ_MSG(t1)
+    sll     t5, t5, 2
+    addu    t4, t4, t5
+    /* Fetch the message to post */
+    lw      t5, 4(t2)
+    addiu   t2, t3, 1
+    /* Post the message to the message queue */
+    sw      t5, (t4)
+    /* Increment the validCount */
+    sw      t2, MQ_VALIDCOUNT(t1)
+    /* If there was a thread blocked on this message queue, */
+    /*  wake it up */
+    lw      t2, MQ_MTQUEUE(t1)
+    lw      t3, (t2)
+    beqz    t3, send_done
+    move    a0, t1
     jal     __osPopThread
-     move    $a0, $t1
-    move    $t2, $v0
-    lui     $a0, %hi(__osRunQueue)
-    move    $a1, $t2
+    move    t2, v0
+    move    a1, t2
+    la      a0, __osRunQueue
     jal     __osEnqueueThread
-     addiu  $a0, %lo(__osRunQueue)
 send_done:
-    jr      $s2
-     nop
+    jr      s2
 
 /**
  *  Handle coprocessor unusable exception
  */
 handle_CpU:
-    li      $at, CAUSE_CEMASK
-    and     $t1, $t0, $at
-    srl     $t1, $t1, CAUSE_CESHIFT
-    li      $t2, 1 // if not coprocessor 1, panic
-    bne     $t1, $t2, panic
-     nop
-    // Mark cop1 as usable for previous thread
-    lw      $k1, THREAD_SR($k0)
-    li      $at, SR_CU1
-    li      $t1, 1
-    or      $k1, $k1, $at
-    sw      $t1, THREAD_FP($k0)
+    and     t1, t0, CAUSE_CEMASK
+    srl     t1, t1, CAUSE_CESHIFT
+    li      t2, 1 /* if not coprocessor 1, panic */
+    bne     t1, t2, panic
+    /* Mark cop1 as usable for previous thread */
+    lw      k1, THREAD_SR(k0)
+    li      t1, 1
+    or      k1, k1, SR_CU1
+    sw      t1, THREAD_FP(k0)
+    sw      k1, THREAD_SR(k0)
     b       enqueueRunning
-     sw     $k1, THREAD_SR($k0)
 END(__osException)
 
 /**
@@ -731,83 +644,71 @@ END(__osException)
  *   unblocked runnable thread.
  */
 LEAF(__osEnqueueAndYield)
-    lui     $a1, %hi(__osRunningThread)
-    lw      $a1, %lo(__osRunningThread)($a1)
-    // Save SR
-    mfc0    $t0, C0_SR
-    lw      $k1, THREAD_FP($a1)
-    ori     $t0, $t0, SR_EXL
-    sw      $t0, THREAD_SR($a1)
-    // Save callee-saved registers
-    sd      $s0, THREAD_S0($a1)
-    sd      $s1, THREAD_S1($a1)
-    sd      $s2, THREAD_S2($a1)
-    sd      $s3, THREAD_S3($a1)
-    sd      $s4, THREAD_S4($a1)
-    sd      $s5, THREAD_S5($a1)
-    sd      $s6, THREAD_S6($a1)
-    sd      $s7, THREAD_S7($a1)
-    sd      $gp, THREAD_GP($a1)
-    sd      $sp, THREAD_SP($a1)
-    sd      $fp, THREAD_S8($a1)
-    sd      $ra, THREAD_RA($a1)
-    // Save FPU callee-saved registers if the current thread has used the FPU
-    beqz    $k1, 1f
-     sw     $ra, THREAD_PC($a1)
-    cfc1    $k1, C1_FPCSR
-    sdc1    $f20, THREAD_FP20($a1)
-    sdc1    $f22, THREAD_FP22($a1)
-    sdc1    $f24, THREAD_FP24($a1)
-    sdc1    $f26, THREAD_FP26($a1)
-    sdc1    $f28, THREAD_FP28($a1)
-    sdc1    $f30, THREAD_FP30($a1)
-    sw      $k1, THREAD_FPCSR($a1)
+    lw      a1, __osRunningThread
+    /* Save SR */
+    MFC0(   t0, C0_SR)
+    lw      k1, THREAD_FP(a1)
+    ori     t0, t0, SR_EXL
+    sw      t0, THREAD_SR(a1)
+    /* Save callee-saved registers */
+    sd      s0, THREAD_S0(a1)
+    sd      s1, THREAD_S1(a1)
+    sd      s2, THREAD_S2(a1)
+    sd      s3, THREAD_S3(a1)
+    sd      s4, THREAD_S4(a1)
+    sd      s5, THREAD_S5(a1)
+    sd      s6, THREAD_S6(a1)
+    sd      s7, THREAD_S7(a1)
+    sd      gp, THREAD_GP(a1)
+    sd      sp, THREAD_SP(a1)
+    sd      fp, THREAD_S8(a1)
+    sd      ra, THREAD_RA(a1)
+    sw      ra, THREAD_PC(a1)
+    /* Save FPU callee-saved registers if the current thread has used the FPU */
+    beqz    k1, 1f
+    cfc1    k1, C1_FPCSR
+    sdc1    $f20, THREAD_FP20(a1)
+    sdc1    $f22, THREAD_FP22(a1)
+    sdc1    $f24, THREAD_FP24(a1)
+    sdc1    $f26, THREAD_FP26(a1)
+    sdc1    $f28, THREAD_FP28(a1)
+    sdc1    $f30, THREAD_FP30(a1)
+    sw      k1, THREAD_FPCSR(a1)
 1:
-    lw      $k1, THREAD_SR($a1)
-    andi    $t1, $k1, SR_IMASK
-    beqz    $t1, 2f
-     nop
-    // This code does the same thing as the block just above the `savercp` label.
-    // See the comment there for more about this.
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, ($t0)
-    li      $at, ~0
-    xor     $t0, $t0, $at
-    lui     $at, ((~SR_IMASK) >> 0x10) & 0xFFFF
-    andi    $t0, $t0, SR_IMASK
-    ori     $at, (~SR_IMASK) & 0xFFFF
-    or      $t1, $t1, $t0
-    and     $k1, $k1, $at
-    or      $k1, $k1, $t1
-    sw      $k1, THREAD_SR($a1)
+    lw      k1, THREAD_SR(a1)
+    andi    t1, k1, SR_IMASK
+    beqz    t1, 2f
+    /* This code does the same thing as the block just above the `savercp` label. */
+    /* See the comment there for more about this. */
+    la      t0, __OSGlobalIntMask
+    lw      t0, (t0)
+    xor     t0, t0, ~0
+    andi    t0, t0, SR_IMASK
+    or      t1, t1, t0
+    and     k1, k1, ~SR_IMASK
+    or      k1, k1, t1
+    sw      k1, THREAD_SR(a1)
 2:
-    lui     $k1, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    lw      $k1, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))($k1)
-    beqz    $k1, 3f
-     nop
-    // This code does the same thing as the block just below the `savercp` label.
-    // See the comment there for more about this.
-    lui     $k0, %hi(__OSGlobalIntMask)
-    addiu   $k0, %lo(__OSGlobalIntMask)
-    lw      $k0, ($k0)
-    lw      $t0, THREAD_RCP($a1)
-    li      $at, ~0
-    srl     $k0, $k0, RCP_IMASKSHIFT
-    xor     $k0, $k0, $at
-    andi    $k0, $k0, (RCP_IMASK >> RCP_IMASKSHIFT)
-    and     $k0, $k0, $t0
-    or      $k1, $k1, $k0
+    lw      k1, PHYS_TO_K1(MI_INTR_MASK_REG)
+    beqz    k1, 3f
+    /* This code does the same thing as the block just below the `savercp` label. */
+    /* See the comment there for more about this. */
+    la      k0, __OSGlobalIntMask
+    lw      k0, (k0)
+    lw      t0, THREAD_RCP(a1)
+    srl     k0, k0, RCP_IMASKSHIFT
+    xor     k0, k0, ~0
+    andi    k0, k0, (RCP_IMASK >> RCP_IMASKSHIFT)
+    and     k0, k0, t0
+    or      k1, k1, k0
 3:
-    // If the specified thread queue is null, skip
-    //  straight to dispatching
-    beqz    $a0, no_enqueue
-     sw     $k1, THREAD_RCP($a1)
+    /* If the specified thread queue is null, skip */
+    /*  straight to dispatching */
+    sw      k1, THREAD_RCP(a1)
+    beqz    a0, no_enqueue
     jal     __osEnqueueThread
-     nop
 no_enqueue:
     j       __osDispatchThread
-     nop
 END(__osEnqueueAndYield)
 
 /**
@@ -816,31 +717,27 @@ END(__osEnqueueAndYield)
  *  Enqueues `thread` to the thread queue `threadQueue`, inserted by priority
  */
 LEAF(__osEnqueueThread)
-    lw      $t8, ($a0)
-    lw      $t7, THREAD_PRI($a1)
-    move    $t9, $a0
-    lw      $t6, THREAD_PRI($t8)
-    slt     $at, $t6, $t7
-    // If the current highest priority thread is a lower priority than
-    //  the new thread, skip searching the queue
-    bnez    $at, 2f
-     nop
+    lw      t8, (a0)
+    lw      t7, THREAD_PRI(a1)
+    move    t9, a0
+    lw      t6, THREAD_PRI(t8)
+    /* If the current highest priority thread is a lower priority than */
+    /*  the new thread, skip searching the queue */
+    blt     t6, t7, 2f
 1:
-    // Search the queue for the position to insert the thread to maintain
-    //  ordering by priority
-    move    $t9, $t8
-    lw      $t8, THREAD_NEXT($t8)
-    lw      $t6, THREAD_PRI($t8)
-    slt     $at, $t6, $t7
-    beqz    $at, 1b
-     nop
+    /* Search the queue for the position to insert the thread to maintain */
+    /*  ordering by priority */
+    move    t9, t8
+    lw      t8, THREAD_NEXT(t8)
+    lw      t6, THREAD_PRI(t8)
+    bge     t6, t7, 1b
 2:
-    // Insert the thread into the queue
-    lw      $t8, ($t9)
-    sw      $t8, THREAD_NEXT($a1)
-    sw      $a1, ($t9)
-    jr      $ra
-     sw     $a0, THREAD_QUEUE($a1)
+    /* Insert the thread into the queue */
+    lw      t8, (t9)
+    sw      t8, THREAD_NEXT(a1)
+    sw      a1, (t9)
+    sw      a0, THREAD_QUEUE(a1)
+    jr      ra
 END(__osEnqueueThread)
 
 /**
@@ -850,16 +747,15 @@ END(__osEnqueueThread)
  *   thread queue `threadQueue` and returns it
  */
 LEAF(__osPopThread)
-    lw      $v0, ($a0)
-    lw      $t9, THREAD_NEXT($v0)
-    jr      $ra
-     sw     $t9, ($a0)
+    lw      v0, (a0)
+    lw      t9, THREAD_NEXT(v0)
+    sw      t9, (a0)
+    jr      ra
 END(__osPopThread)
 
 #if LIBULTRA_VERSION >= LIBULTRA_VERSION_K
 LEAF(__osNop)
-    jr      $ra
-     nop
+    jr      ra
 END(__osNop)
 #endif
 
@@ -869,113 +765,111 @@ END(__osNop)
  *  Dispatches the next thread to run after restoring the context
  */
 LEAF(__osDispatchThread)
-    // Obtain highest priority thread from the active run queue
-    lui     $a0, %hi(__osRunQueue)
+    /* Obtain highest priority thread from the active run queue */
+    la      a0, __osRunQueue
     jal     __osPopThread
-     addiu  $a0, $a0, %lo(__osRunQueue)
-    // Set thread as running
-    lui     $at, %hi(__osRunningThread)
-    sw      $v0, %lo(__osRunningThread)($at)
-    li      $t0, OS_STATE_RUNNING
-    sh      $t0, THREAD_STATE($v0)
-    // Restore SR, masking out any interrupts that are not also
-    // enabled in the global interrupt mask
-    move    $k0, $v0
-    lui     $t0, %hi(__OSGlobalIntMask)
-    lw      $k1, THREAD_SR($k0)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, ($t0)
-    lui     $at, ((~SR_IMASK) >> 0x10) & 0xFFFF
-    andi    $t1, $k1, SR_IMASK
-    ori     $at, (~SR_IMASK) & 0xFFFF
-    andi    $t0, $t0, SR_IMASK
-    and     $t1, $t1, $t0
-    and     $k1, $k1, $at
-    or      $k1, $k1, $t1
-    mtc0    $k1, C0_SR
-    // Restore GPRs
-    ld      $k1, THREAD_LO($k0)
-    ld      $at, THREAD_AT($k0)
-    ld      $v0, THREAD_V0($k0)
-    mtlo    $k1
-    ld      $k1, THREAD_HI($k0)
-    ld      $v1, THREAD_V1($k0)
-    ld      $a0, THREAD_A0($k0)
-    ld      $a1, THREAD_A1($k0)
-    ld      $a2, THREAD_A2($k0)
-    ld      $a3, THREAD_A3($k0)
-    ld      $t0, THREAD_T0($k0)
-    ld      $t1, THREAD_T1($k0)
-    ld      $t2, THREAD_T2($k0)
-    ld      $t3, THREAD_T3($k0)
-    ld      $t4, THREAD_T4($k0)
-    ld      $t5, THREAD_T5($k0)
-    ld      $t6, THREAD_T6($k0)
-    ld      $t7, THREAD_T7($k0)
-    ld      $s0, THREAD_S0($k0)
-    ld      $s1, THREAD_S1($k0)
-    ld      $s2, THREAD_S2($k0)
-    ld      $s3, THREAD_S3($k0)
-    ld      $s4, THREAD_S4($k0)
-    ld      $s5, THREAD_S5($k0)
-    ld      $s6, THREAD_S6($k0)
-    ld      $s7, THREAD_S7($k0)
-    ld      $t8, THREAD_T8($k0)
-    ld      $t9, THREAD_T9($k0)
-    ld      $gp, THREAD_GP($k0)
-    mthi    $k1
-    ld      $sp, THREAD_SP($k0)
-    ld      $fp, THREAD_S8($k0)
-    ld      $ra, THREAD_RA($k0)
-    // Move thread pc to EPC so that eret will return execution to where the thread left off
-    lw      $k1, THREAD_PC($k0)
-    mtc0    $k1, C0_EPC
-    // Check if the FPU was used by this thread and if so also restore the FPU registers
-    lw      $k1, THREAD_FP($k0)
-    beqz    $k1, 1f
-     nop
-    lw      $k1, THREAD_FPCSR($k0)
-    ctc1    $k1, C1_FPCSR
-    ldc1    $f0, THREAD_FP0($k0)
-    ldc1    $f2, THREAD_FP2($k0)
-    ldc1    $f4, THREAD_FP4($k0)
-    ldc1    $f6, THREAD_FP6($k0)
-    ldc1    $f8, THREAD_FP8($k0)
-    ldc1    $f10, THREAD_FP10($k0)
-    ldc1    $f12, THREAD_FP12($k0)
-    ldc1    $f14, THREAD_FP14($k0)
-    ldc1    $f16, THREAD_FP16($k0)
-    ldc1    $f18, THREAD_FP18($k0)
-    ldc1    $f20, THREAD_FP20($k0)
-    ldc1    $f22, THREAD_FP22($k0)
-    ldc1    $f24, THREAD_FP24($k0)
-    ldc1    $f26, THREAD_FP26($k0)
-    ldc1    $f28, THREAD_FP28($k0)
-    ldc1    $f30, THREAD_FP30($k0)
+    /* Set thread as running */
+    sw      v0, __osRunningThread
+    li      t0, OS_STATE_RUNNING
+    sh      t0, THREAD_STATE(v0)
+    /* Restore SR, masking out any interrupts that are not also */
+    /* enabled in the global interrupt mask */
+    move    k0, v0
+    lw      k1, THREAD_SR(k0)
+    la      t0, __OSGlobalIntMask
+    lw      t0, (t0)
+    andi    t1, k1, SR_IMASK
+    andi    t0, t0, SR_IMASK
+    and     t1, t1, t0
+    and     k1, k1, ~SR_IMASK
+    or      k1, k1, t1
+    MTC0(   k1, C0_SR)
+    /* Restore GPRs */
+.set noat
+    ld      AT, THREAD_AT(k0)
+    ld      v0, THREAD_V0(k0)
+    ld      v1, THREAD_V1(k0)
+    ld      a0, THREAD_A0(k0)
+    ld      a1, THREAD_A1(k0)
+    ld      a2, THREAD_A2(k0)
+    ld      a3, THREAD_A3(k0)
+    ld      t0, THREAD_T0(k0)
+    ld      t1, THREAD_T1(k0)
+    ld      t2, THREAD_T2(k0)
+    ld      t3, THREAD_T3(k0)
+    ld      t4, THREAD_T4(k0)
+    ld      t5, THREAD_T5(k0)
+    ld      t6, THREAD_T6(k0)
+    ld      t7, THREAD_T7(k0)
+    ld      s0, THREAD_S0(k0)
+    ld      s1, THREAD_S1(k0)
+    ld      s2, THREAD_S2(k0)
+    ld      s3, THREAD_S3(k0)
+    ld      s4, THREAD_S4(k0)
+    ld      s5, THREAD_S5(k0)
+    ld      s6, THREAD_S6(k0)
+    ld      s7, THREAD_S7(k0)
+    ld      t8, THREAD_T8(k0)
+    ld      t9, THREAD_T9(k0)
+    ld      gp, THREAD_GP(k0)
+    ld      k1, THREAD_LO(k0)
+    mtlo    k1
+    ld      k1, THREAD_HI(k0)
+    mthi    k1
+    ld      sp, THREAD_SP(k0)
+    ld      fp, THREAD_S8(k0)
+    ld      ra, THREAD_RA(k0)
+    /* Move thread pc to EPC so that eret will return execution to where the thread left off */
+    lw      k1, THREAD_PC(k0)
+    MTC0(   k1, C0_EPC)
+    /* Check if the FPU was used by this thread and if so also restore the FPU registers */
+    lw      k1, THREAD_FP(k0)
+    beqz    k1, 1f
+
+.set noreorder 
+    lw      k1, THREAD_FPCSR(k0)
+    ctc1    k1, C1_FPCSR
+.set reorder
+    ldc1    $f0, THREAD_FP0(k0)
+    ldc1    $f2, THREAD_FP2(k0)
+    ldc1    $f4, THREAD_FP4(k0)
+    ldc1    $f6, THREAD_FP6(k0)
+    ldc1    $f8, THREAD_FP8(k0)
+    ldc1    $f10, THREAD_FP10(k0)
+    ldc1    $f12, THREAD_FP12(k0)
+    ldc1    $f14, THREAD_FP14(k0)
+    ldc1    $f16, THREAD_FP16(k0)
+    ldc1    $f18, THREAD_FP18(k0)
+    ldc1    $f20, THREAD_FP20(k0)
+    ldc1    $f22, THREAD_FP22(k0)
+    ldc1    $f24, THREAD_FP24(k0)
+    ldc1    $f26, THREAD_FP26(k0)
+    ldc1    $f28, THREAD_FP28(k0)
+    ldc1    $f30, THREAD_FP30(k0)
 1:
-    // Restore RCP interrupt mask, masking out any RCP interrupts that
-    // are not also enabled in the global interrupt mask
-    lw      $k1, THREAD_RCP($k0)
-    lui     $k0, %hi(__OSGlobalIntMask)
-    addiu   $k0, %lo(__OSGlobalIntMask)
-    lw      $k0, ($k0)
-    srl     $k0, $k0, RCP_IMASKSHIFT
-    and     $k1, $k1, $k0
-    sll     $k1, $k1, 1
-    lui     $k0, %hi(__osRcpImTable)
-    addiu   $k0, %lo(__osRcpImTable)
-    addu    $k1, $k1, $k0
-    lhu     $k1, ($k1)
-    lui     $k0, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    addiu   $k0, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))
-    sw      $k1, ($k0)
-    // Empty pipeline
+    /* Restore RCP interrupt mask, masking out any RCP interrupts that */
+    /* are not also enabled in the global interrupt mask */
+.set noreorder
+    lw      k1, THREAD_RCP(k0)
+    la      k0, __OSGlobalIntMask
+    lw      k0, (k0)
+    srl     k0, k0, RCP_IMASKSHIFT
+    and     k1, k1, k0
+    sll     k1, k1, 1
+    la      k0, __osRcpImTable
+    addu    k1, k1, k0
+    lhu     k1, (k1)
+    la      k0, PHYS_TO_K1(MI_INTR_MASK_REG)
+    sw      k1, (k0)
+    /* Empty pipeline */
     nop
     nop
     nop
     nop
-    // Resume thread execution
+    /* Resume thread execution */
     eret
+.set reorder
+.set at
 END(__osDispatchThread)
 
 /**
@@ -986,7 +880,7 @@ END(__osDispatchThread)
  *  current thread to be destroyed.
  */
 LEAF(__osCleanupThread)
+    move    a0, zero
     jal     osDestroyThread
-     move   $a0, $zero
-    // Despite being a jal, this function does not return as the thread will have been destroyed
+    /* Despite being a jal, this function does not return as the thread will have been destroyed */
 END(__osCleanupThread)
diff --git a/src/libultra/os/getcause.s b/src/libultra/os/getcause.s
index a621e9736..b59c5c680 100644
--- a/src/libultra/os/getcause.s
+++ b/src/libultra/os/getcause.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osGetCause)
-    mfc0    $v0, C0_CAUSE
-    jr      $ra
-     nop
+    MFC0(   v0, C0_CAUSE)
+    jr      ra
 END(__osGetCause)
diff --git a/src/libultra/os/getcount.s b/src/libultra/os/getcount.s
index 242c9da69..84552adb0 100644
--- a/src/libultra/os/getcount.s
+++ b/src/libultra/os/getcount.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(osGetCount)
-    mfc0    $v0, C0_COUNT
-    jr      $ra
-     nop
+    MFC0(   v0, C0_COUNT)
+    jr      ra
 END(osGetCount)
diff --git a/src/libultra/os/getfpccsr.s b/src/libultra/os/getfpccsr.s
index 93d4e51b8..37c0e8c3b 100644
--- a/src/libultra/os/getfpccsr.s
+++ b/src/libultra/os/getfpccsr.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osGetFpcCsr)
-    cfc1    $v0, C1_FPCSR
-    jr      $ra
-     nop
+    CFC1(   v0, C1_FPCSR)
+    jr      ra
 END(__osGetFpcCsr)
diff --git a/src/libultra/os/getintmask.s b/src/libultra/os/getintmask.s
index 2c6ddc86e..f73410393 100644
--- a/src/libultra/os/getintmask.s
+++ b/src/libultra/os/getintmask.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 #include "ultra64/rcp.h"
 #include "ultra64/exception.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  *  OSIntMask osGetIntMask(void);
@@ -23,38 +19,35 @@
  *       See the comment for osSetIntMask for more details.
  */
 LEAF(osGetIntMask)
-    // Extract interrupt enable bits from current SR
-    mfc0    $v0, C0_SR
-    andi    $v0, $v0, (SR_IMASK | SR_IE)
-    // Get value of __OSGlobalIntMask
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t1, 0($t0)
-    // Bitwise-OR in the disabled CPU bits of __OSGlobalIntMask
-    li      $at, ~0
-    xor     $t0, $t1, $at
-    andi    $t0, $t0, SR_IMASK
-    or      $v0, $v0, $t0
-    // Fetch MI_INTR_MASK_REG
-    lui     $t1, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    lw      $t1, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))($t1)
-    // If there are RCP interrupts masked
-    beqz    $t1, 1f
-    // Get value of __OSGlobalIntMask
-     lui    $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t0, 0($t0)
-    // Bitwise-OR in the disabled RCP bits of __OSGlobalIntMask
-    srl     $t0, $t0, RCP_IMASKSHIFT
-    li      $at, ~0
-    xor     $t0, $t0, $at
-    andi    $t0, $t0, (RCP_IMASK >> RCP_IMASKSHIFT)
-    or      $t1, $t1, $t0
+.set noreorder
+    /* Extract interrupt enable bits from current SR */
+    mfc0    v0, C0_SR
+    andi    v0, v0, (SR_IMASK | SR_IE)
+    /* Get value of __OSGlobalIntMask */
+    la      t0, __OSGlobalIntMask
+    lw      t1, (t0)
+    /* Bitwise-OR in the disabled CPU bits of __OSGlobalIntMask */
+    xor     t0, t1, ~0
+    andi    t0, t0, SR_IMASK
+    or      v0, v0, t0
+    /* Fetch MI_INTR_MASK_REG */
+    lw      t1, PHYS_TO_K1(MI_INTR_MASK_REG)
+    /* If there are RCP interrupts masked */
+    beqz    t1, 1f
+    /* Get value of __OSGlobalIntMask */
+     la     t0, __OSGlobalIntMask /* Note: macro expansion in delay slot */
+    lw      t0, (t0)
+    /* Bitwise-OR in the disabled RCP bits of __OSGlobalIntMask */
+    srl     t0, t0, RCP_IMASKSHIFT
+    xor     t0, t0, ~0
+    andi    t0, t0, (RCP_IMASK >> RCP_IMASKSHIFT)
+    or      t1, t1, t0
 1:
-    // Shift the RCP bits to not conflict with the CPU bits
-    sll     $t2, $t1, RCP_IMASKSHIFT
-    // OR the CPU and RCP bits together
-    or      $v0, $v0, $t2
-    jr      $ra
+    /* Shift the RCP bits to not conflict with the CPU bits */
+    sll     t2, t1, RCP_IMASKSHIFT
+    /* OR the CPU and RCP bits together */
+    or      v0, v0, t2
+    jr      ra
      nop
+.set reorder
 END(osGetIntMask)
diff --git a/src/libultra/os/getsr.s b/src/libultra/os/getsr.s
index dc6901b98..709075a7b 100644
--- a/src/libultra/os/getsr.s
+++ b/src/libultra/os/getsr.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osGetSR)
-    mfc0    $v0, C0_SR
-    jr      $ra
-     nop
+    MFC0(   v0, C0_SR)
+    jr      ra
 END(__osGetSR)
diff --git a/src/libultra/os/interrupt.s b/src/libultra/os/interrupt.s
index 829377bb0..3a9102c57 100644
--- a/src/libultra/os/interrupt.s
+++ b/src/libultra/os/interrupt.s
@@ -1,53 +1,45 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 #include "ultra64/thread.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osDisableInt)
-    lui     $t2, %hi(__OSGlobalIntMask)
-    addiu   $t2, $t2, %lo(__OSGlobalIntMask)
-    lw      $t3, ($t2)
-    andi    $t3, $t3, SR_IMASK
-    mfc0    $t0, C0_SR
-    li      $at, ~SR_IE
-    and     $t1, $t0, $at
-    mtc0    $t1, C0_SR
-    andi    $v0, $t0, SR_IE
-    lw      $t0, ($t2)
-    andi    $t0, $t0, SR_IMASK
-    beq     $t0, $t3, No_Change_Global_Int
-     lui    $t2, %hi(__osRunningThread)
-    //! @bug this addiu should be lw, it may never come up in practice as to reach this code
-    //! the CPU bits of __OSGlobalIntMask must have changed while this function is running.
-    addiu   $t2, $t2, %lo(__osRunningThread)
-    lw      $t1, THREAD_SR($t2)
-    andi    $t2, $t1, SR_IMASK
-    and     $t2, $t2, $t0
-    li      $at, ~SR_IMASK
-    and     $t1, $t1, $at
-    or      $t1, $t1, $t2
-    li      $at, ~SR_IE
-    and     $t1, $t1, $at
-    mtc0    $t1, C0_SR
-    nop
-    nop
+    la      t2, __OSGlobalIntMask
+    lw      t3, (t2)
+    and     t3, t3, SR_IMASK
+    MFC0(   t0, C0_SR)
+    and     t1, t0, ~SR_IE
+    MTC0(   t1, C0_SR)
+    and     v0, t0, SR_IE
+    lw      t0, (t2)
+    and     t0, t0, SR_IMASK
+.set noreorder
+    beq     t0, t3, No_Change_Global_Int
+    /*! @bug this la should be lw, it may never come up in practice as to reach this code
+     *! the CPU bits of __OSGlobalIntMask must have changed while this function is running.
+     */
+    la      t2, __osRunningThread
+    lw      t1, THREAD_SR(t2)
+    and     t2, t1, SR_IMASK
+    and     t2, t2, t0
+.set reorder
+    and     t1, t1, ~SR_IMASK
+    or      t1, t1, t2
+    and     t1, t1, ~SR_IE
+    MTC0(   t1, C0_SR)
+    NOP
+    NOP
 No_Change_Global_Int:
-    jr      $ra
-     nop
+    jr      ra
 END(__osDisableInt)
 
 LEAF(__osRestoreInt)
-    mfc0    $t0, C0_SR
-    or      $t0, $t0, $a0
-    mtc0    $t0, C0_SR
-    nop
-    nop
-    jr      $ra
-     nop
+    MFC0(   t0, C0_SR)
+    or      t0, t0, a0
+    MTC0(   t0, C0_SR)
+    NOP
+    NOP
+    jr      ra
 END(__osRestoreInt)
diff --git a/src/libultra/os/invaldcache.s b/src/libultra/os/invaldcache.s
index 9464a24da..22109e13a 100644
--- a/src/libultra/os/invaldcache.s
+++ b/src/libultra/os/invaldcache.s
@@ -1,12 +1,8 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  *  void osInvalDCache(void* vaddr, s32 nbytes);
@@ -24,71 +20,67 @@
  *  the entire data cache is invalidated.
  */
 LEAF(osInvalDCache)
-    // If the amount to invalidate is less than or equal to 0, return immediately
-    blez    $a1, 3f
+.set noreorder
+    /* If the amount to invalidate is less than or equal to 0, return immediately */
+    blez    a1, 3f
      nop
-    // If the amount to invalidate is as large as or larger than
-    // the data cache size, invalidate all
-    li      $t3, DCACHE_SIZE
-    sltu    $at, $a1, $t3
-    beqz    $at, 4f
+    /* If the amount to invalidate is as large as or larger than
+     * the data cache size, invalidate all */
+    li      t3, DCACHE_SIZE
+    bgeu    a1, t3, 4f
      nop
-    // Ensure end address doesn't wrap around and end up smaller
-    // than the start address
-    move    $t0, $a0
-    addu    $t1, $a0, $a1
-    sltu    $at, $t0, $t1
-    beqz    $at, 3f
+    /* Ensure end address doesn't wrap around and end up smaller
+     * than the start address */
+    move    t0, a0
+    addu    t1, a0, a1
+    bgeu    t0, t1, 3f
      nop
-    // Mask start with cache line
-    andi    $t2, $t0, DCACHE_LINEMASK
-    // If mask is not zero, the start is not cache aligned
-    beqz    $t2, 1f
-     addiu  $t1, $t1, -DCACHE_LINESIZE
-    // Subtract mask result to align to cache line
-    subu    $t0, $t0, $t2
-    // Hit-Writeback-Invalidate unaligned part
-    cache   (CACH_PD | C_HWBINV), ($t0)
-    sltu    $at, $t0, $t1
-    // If that's all there is to do, return early
-    beqz    $at, 3f
+    /* Mask start with cache line */
+    andi    t2, t0, DCACHE_LINEMASK
+    /* If mask is not zero, the start is not cache aligned */
+    beqz    t2, 1f
+     addiu  t1, t1, -DCACHE_LINESIZE
+    /* Subtract mask result to align to cache line */
+    subu    t0, t0, t2
+    /* Hit-Writeback-Invalidate unaligned part */
+    cache   (CACH_PD | C_HWBINV), (t0)
+    /* If that's all there is to do, return early */
+    bgeu    t0, t1, 3f
      nop
-    addiu   $t0, $t0, DCACHE_LINESIZE
+    addiu   t0, t0, DCACHE_LINESIZE
 1:
-    // Mask end with cache line
-    andi    $t2, $t1, DCACHE_LINEMASK
-    // If mask is not zero, the end is not cache aligned
-    beqz    $t2, 1f
+    /* Mask end with cache line */
+    andi    t2, t1, DCACHE_LINEMASK
+    /* If mask is not zero, the end is not cache aligned */
+    beqz    t2, 1f
      nop
-    // Subtract mask result to align to cache line
-    subu    $t1, $t1, $t2
-    // Hit-Writeback-Invalidate unaligned part
-    cache   (CACH_PD | C_HWBINV), DCACHE_LINESIZE($t1)
-    sltu    $at, $t1, $t0
-    // If that's all there is to do, return early
-    bnez    $at, 3f
+    /* Subtract mask result to align to cache line */
+    subu    t1, t1, t2
+    /* Hit-Writeback-Invalidate unaligned part */
+    cache   (CACH_PD | C_HWBINV), DCACHE_LINESIZE(t1)
+    /* If that's all there is to do, return early */
+    bltu    t1, t0, 3f
      nop
-    // Invalidate the rest
+    /* Invalidate the rest */
 1:
-    // Hit-Invalidate
-    cache   (CACH_PD | C_HINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 1b
-     addiu  $t0, $t0, DCACHE_LINESIZE
+    /* Hit-Invalidate */
+    cache   (CACH_PD | C_HINV), (t0)
+    bltu    t0, t1, 1b
+     addiu  t0, t0, DCACHE_LINESIZE
 3:
-    jr      $ra
+    jr      ra
      nop
 
 4:
-    li      $t0, K0BASE
-    addu    $t1, $t0, $t3
-    addiu   $t1, $t1, -DCACHE_LINESIZE
+    li      t0, K0BASE
+    addu    t1, t0, t3
+    addiu   t1, t1, -DCACHE_LINESIZE
 5:
-    // Index-Writeback-Invalidate
-    cache   (CACH_PD | C_IWBINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 5b
-     addiu  $t0, DCACHE_LINESIZE
-    jr      $ra
+    /* Index-Writeback-Invalidate */
+    cache   (CACH_PD | C_IWBINV), (t0)
+    bltu    t0, t1, 5b
+     addiu  t0, DCACHE_LINESIZE
+    jr      ra
      nop
+.set reorder
 END(osInvalDCache)
diff --git a/src/libultra/os/invalicache.s b/src/libultra/os/invalicache.s
index 55f831238..757215cf1 100644
--- a/src/libultra/os/invalicache.s
+++ b/src/libultra/os/invalicache.s
@@ -1,52 +1,46 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(osInvalICache)
-    // If the amount to invalidate is less than or equal to 0, return immediately
-    blez    $a1, 2f
+.set noreorder
+    /* If the amount to invalidate is less than or equal to 0, return immediately */
+    blez    a1, 2f
      nop
-    // If the amount to invalidate is as large as or larger than
-    // the instruction cache size, invalidate all
-    li      $t3, ICACHE_SIZE
-    sltu    $at, $a1, $t3
-    beqz    $at, 3f
+    /* If the amount to invalidate is as large as or larger than */
+    /* the instruction cache size, invalidate all */
+    li      t3, ICACHE_SIZE
+    bgeu    a1, t3, 3f
      nop
-    // ensure end address doesn't wrap around and end up smaller
-    // than the start address
-    move    $t0, $a0
-    addu    $t1, $a0, $a1
-    sltu    $at, $t0, $t1
-    beqz    $at, 2f
+    /* ensure end address doesn't wrap around and end up smaller */
+    /* than the start address */
+    move    t0, a0
+    addu    t1, a0, a1
+    bgeu    t0, t1, 2f
      nop
-    // Mask and subtract to align to cache line
-    andi    $t2, $t0, ICACHE_LINEMASK
-    addiu   $t1, $t1, -ICACHE_LINESIZE
-    subu    $t0, $t0, $t2
+    /* Mask and subtract to align to cache line */
+    andi    t2, t0, ICACHE_LINEMASK
+    addiu   t1, t1, -ICACHE_LINESIZE
+    subu    t0, t0, t2
 1:
-    cache   (CACH_PI | C_HINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 1b
-     addiu  $t0, $t0, ICACHE_LINESIZE
+    cache   (CACH_PI | C_HINV), (t0)
+    bltu    t0, t1, 1b
+     addiu  t0, t0, ICACHE_LINESIZE
 2:
-    jr      $ra
+    jr      ra
      nop
 
 3:
-    li      $t0, K0BASE
-    addu    $t1, $t0, $t3
-    addiu   $t1, $t1, -ICACHE_LINESIZE
+    li      t0, K0BASE
+    addu    t1, t0, t3
+    addiu   t1, t1, -ICACHE_LINESIZE
 4:
-    cache   (CACH_PI | C_IINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 4b
-     addiu  $t0, ICACHE_LINESIZE
-    jr      $ra
+    cache   (CACH_PI | C_IINV), (t0)
+    bltu    t0, t1, 4b
+     addiu  t0, ICACHE_LINESIZE
+    jr      ra
      nop
+.set reorder
 END(osInvalICache)
diff --git a/src/libultra/os/maptlbrdb.s b/src/libultra/os/maptlbrdb.s
index c3ac20948..43e7cc93a 100644
--- a/src/libultra/os/maptlbrdb.s
+++ b/src/libultra/os/maptlbrdb.s
@@ -1,36 +1,31 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 #include "ultra64/rdb.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(osMapTLBRdb)
-    mfc0    $t0, C0_ENTRYHI
-    li      $t1, NTLBENTRIES
-    mtc0    $t1, C0_INX
-    mtc0    $zero, C0_PAGEMASK
-    li      $t2, (TLBLO_UNCACHED | TLBLO_D | TLBLO_V | TLBLO_G)
-    li      $t1, (RDB_BASE_REG & TLBHI_VPN2MASK)
-    mtc0    $t1, C0_ENTRYHI
-    // Possible bug? Virtual address instead of physical address
-    // set as page frame number
-    li      $t1, RDB_BASE_VIRTUAL_ADDR
-    srl     $t3, $t1, TLBLO_PFNSHIFT
-    or      $t3, $t3, $t2
-    mtc0    $t3, C0_ENTRYLO0
-    li      $t1, TLBLO_G
-    mtc0    $t1, C0_ENTRYLO1
-    nop
-    tlbwi
-    nop
-    nop
-    nop
-    nop
-    mtc0    $t0, C0_ENTRYHI
-    jr      $ra
-     nop
+    MFC0(   t0, C0_ENTRYHI)
+    li      t1, NTLBENTRIES
+    MTC0(   t1, C0_INX)
+    MTC0(   zero, C0_PAGEMASK)
+    li      t2, (TLBLO_UNCACHED | TLBLO_D | TLBLO_V | TLBLO_G)
+    li      t1, (RDB_BASE_REG & TLBHI_VPN2MASK)
+    MTC0(   t1, C0_ENTRYHI)
+    /* Possible bug? Virtual address instead of physical address set as page frame number */
+    li      t1, RDB_BASE_VIRTUAL_ADDR
+    srl     t3, t1, TLBLO_PFNSHIFT
+    or      t3, t3, t2
+    MTC0(   t3, C0_ENTRYLO0)
+    li      t1, TLBLO_G
+    MTC0(   t1, C0_ENTRYLO1)
+    NOP
+    TLBWI
+    NOP
+    NOP
+    NOP
+    NOP
+    MTC0(   t0, C0_ENTRYHI)
+    jr      ra
 END(osMapTLBRdb)
diff --git a/src/libultra/os/parameters.s b/src/libultra/os/parameters.s
index c0020ddbe..b88114814 100644
--- a/src/libultra/os/parameters.s
+++ b/src/libultra/os/parameters.s
@@ -1,22 +1,29 @@
 #include "ultra64/asm.h"
 
-.section .text
+.text
 
-.macro IPL_SYMBOL name, address, size
-    .global \name
-    .set \name, \address
-    .type \name, @object
-    .size \name, \size
-.endm
+#ifdef __sgi
+#define IPL_SYMBOL(name, address, size) \
+    ABS(name, address)
+#else
+#define IPL_SYMBOL(name, address, sz) \
+    ABS(name, address)               ;\
+    .type name, @object              ;\
+    .size name, sz
+#endif
 
-IPL_SYMBOL leoBootID,       0x800001A0, 4
-IPL_SYMBOL osTvType,        0x80000300, 4
-IPL_SYMBOL osRomType,       0x80000304, 4
-IPL_SYMBOL osRomBase,       0x80000308, 4
-IPL_SYMBOL osResetType,     0x8000030C, 4
-IPL_SYMBOL osCicId,         0x80000310, 4
-IPL_SYMBOL osVersion,       0x80000314, 4
-IPL_SYMBOL osMemSize,       0x80000318, 4
-IPL_SYMBOL osAppNMIBuffer,  0x8000031C, 0x40
 
-.fill 0x60
+IPL_SYMBOL(leoBootID,      0x800001A0, 4)
+IPL_SYMBOL(osTvType,       0x80000300, 4)
+IPL_SYMBOL(osRomType,      0x80000304, 4)
+IPL_SYMBOL(osRomBase,      0x80000308, 4)
+IPL_SYMBOL(osResetType,    0x8000030C, 4)
+IPL_SYMBOL(osCicId,        0x80000310, 4)
+IPL_SYMBOL(osVersion,      0x80000314, 4)
+IPL_SYMBOL(osMemSize,      0x80000318, 4)
+IPL_SYMBOL(osAppNMIBuffer, 0x8000031C, 0x40)
+
+
+.repeat 0x60/4
+    NOP
+.endr
diff --git a/src/libultra/os/probetlb.s b/src/libultra/os/probetlb.s
index 7bc7856e1..4fa8abc38 100644
--- a/src/libultra/os/probetlb.s
+++ b/src/libultra/os/probetlb.s
@@ -1,12 +1,8 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  *  u32 __osProbeTLB(void* vaddr);
@@ -17,70 +13,71 @@
  *  Returns the physical address if found, or -1 if not found.
  */
 LEAF(__osProbeTLB)
-    // Set C0_ENTRYHI based on supplied vaddr
-    mfc0    $t0, C0_ENTRYHI
-    andi    $t1, $t0, TLBHI_PIDMASK
-    li      $at, TLBHI_VPN2MASK
-    and     $t2, $a0, $at
-    or      $t1, $t1, $t2
-    mtc0    $t1, C0_ENTRYHI
+.set noreorder
+    /* Set C0_ENTRYHI based on supplied vaddr */
+    mfc0    t0, C0_ENTRYHI
+    and     t1, t0, TLBHI_PIDMASK
+    and     t2, a0, TLBHI_VPN2MASK
+    or      t1, t1, t2
+    mtc0    t1, C0_ENTRYHI
     nop
     nop
     nop
-    // TLB probe, sets C0_INX to a value matching C0_ENTRYHI.
-    // If no match is found the TLBINX_PROBE bit is set to indicate this.
+    /* TLB probe, sets C0_INX to a value matching C0_ENTRYHI. */
+    /* If no match is found the TLBINX_PROBE bit is set to indicate this. */
     tlbp
     nop
     nop
-    // Read result
-    mfc0    $t3, C0_INX
-    li      $at, TLBINX_PROBE
-    and     $t3, $t3, $at
-    // Branch if no match was found
-    bnez    $t3, 3f
+    /* Read result */
+    mfc0    t3, C0_INX
+    and     t3, t3, TLBINX_PROBE
+    /* Branch if no match was found */
+    bnez    t3, 3f
      nop
-    // Read TLB, sets C0_ENTRYHI, C0_ENTRYLO0, C0_ENTRYLO1 and C0_PAGEMASK for the TLB
-    // entry indicated by C0_INX
+
+    /* Read TLB, sets C0_ENTRYHI, C0_ENTRYLO0, C0_ENTRYLO1 and C0_PAGEMASK for the TLB */
+    /* entry indicated by C0_INX */
     tlbr
     nop
     nop
     nop
-    // Calculate page size = (page mask + 0x2000) >> 1
-    mfc0    $t3, C0_PAGEMASK
-    addi    $t3, $t3, 0x2000
-    srl     $t3, $t3, 1
-    // & with vaddr
-    and     $t4, $t3, $a0
-    // Select C0_ENTRYLO0 or C0_ENTRYLO1
-    bnez    $t4, 1f
-     addi   $t3, $t3, -1 // make bitmask out of page size
-    mfc0    $v0, C0_ENTRYLO0
+    /* Calculate page size = (page mask + 0x2000) >> 1 */
+    mfc0    t3, C0_PAGEMASK
+    add     t3, t3, 0x2000
+    srl     t3, t3, 1
+    /* & with vaddr */
+    and     t4, t3, a0
+    /* Select C0_ENTRYLO0 or C0_ENTRYLO1 */
+    bnez    t4, 1f
+     add    t3, t3, -1 /* make bitmask out of page size */
+    mfc0    v0, C0_ENTRYLO0
     b       2f
      nop
 1:
-    mfc0    $v0, C0_ENTRYLO1
+    mfc0    v0, C0_ENTRYLO1
 2:
-    // Check valid bit and branch if not valid
-    andi    $t5, $v0, TLBLO_V
-    beqz    $t5, 3f
+    /* Check valid bit and branch if not valid */
+    and     t5, v0, TLBLO_V
+    beqz    t5, 3f
      nop
-    // Extract the Page Frame Number from the entry
-    li      $at, TLBLO_PFNMASK
-    and     $v0, $v0, $at
-    sll     $v0, $v0, TLBLO_PFNSHIFT
-    // Mask vaddr with page size mask
-    and     $t5, $a0, $t3
-    // Add masked vaddr to pfn to obtain the physical address
-    add     $v0, $v0, $t5
+
+    /* Extract the Page Frame Number from the entry */
+    and     v0, v0, TLBLO_PFNMASK
+    sll     v0, v0, TLBLO_PFNSHIFT
+    /* Mask vaddr with page size mask */
+    and     t5, a0, t3
+    /* Add masked vaddr to pfn to obtain the physical address */
+    add     v0, v0, t5
     b       4f
      nop
 3:
-    // No physical address for the supplied virtual address was found,
-    // return -1
-    li      $v0, -1
+    /* No physical address for the supplied virtual address was found, */
+    /* return -1 */
+    li      v0, -1
 4:
-    // Restore original C0_ENTRYHI value before returning
-    mtc0    $t0, C0_ENTRYHI
-    jr      $ra
+    /* Restore original C0_ENTRYHI value before returning */
+    mtc0    t0, C0_ENTRYHI
+    jr      ra
      nop
+.set reorder
 END(__osProbeTLB)
diff --git a/src/libultra/os/setcompare.s b/src/libultra/os/setcompare.s
index bd1653377..3c175c494 100644
--- a/src/libultra/os/setcompare.s
+++ b/src/libultra/os/setcompare.s
@@ -1,14 +1,10 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osSetCompare)
-    mtc0    $a0, C0_COMPARE
-    jr      $ra
-     nop
+    MTC0(   a0, C0_COMPARE)
+    jr      ra
 END(__osSetCompare)
diff --git a/src/libultra/os/setfpccsr.s b/src/libultra/os/setfpccsr.s
index 1aa0e7d29..e33355084 100644
--- a/src/libultra/os/setfpccsr.s
+++ b/src/libultra/os/setfpccsr.s
@@ -1,15 +1,11 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osSetFpcCsr)
-    cfc1    $v0, C1_FPCSR
-    ctc1    $a0, C1_FPCSR
-    jr      $ra
-     nop
+    CFC1(   v0, C1_FPCSR)
+    CTC1(   a0, C1_FPCSR)
+    jr      ra
 END(__osSetFpcCsr)
diff --git a/src/libultra/os/setintmask.s b/src/libultra/os/setintmask.s
index e48c1b376..bf6bec020 100644
--- a/src/libultra/os/setintmask.s
+++ b/src/libultra/os/setintmask.s
@@ -1,14 +1,11 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 #include "ultra64/rcp.h"
 #include "ultra64/exception.h"
 
-.set noat
-.set noreorder
-
-.section .rodata
-
-.balign 16
+.rdata
+.align 2
 
 /**
  *  LUT to convert between an interrupt mask value and a value for MI_INTR_MASK_REG.
@@ -82,9 +79,7 @@ DATA(__osRcpImTable)
     .half MI_INTR_MASK_SET_SP | MI_INTR_MASK_SET_SI | MI_INTR_MASK_SET_AI | MI_INTR_MASK_SET_VI | MI_INTR_MASK_SET_PI | MI_INTR_MASK_SET_DP
 ENDDATA(__osRcpImTable)
 
-.section .text
-
-.balign 16
+.text
 
 /**
  *  OSIntMask osSetIntMask(OSIntMask);
@@ -113,56 +108,47 @@ ENDDATA(__osRcpImTable)
  *       OS_IM_ALL, so the operation is usually simply (SR | 0).
  */
 LEAF(osSetIntMask)
-    // Extract interrupt enable bits from current SR
-    mfc0    $t4, C0_SR
-    andi    $v0, $t4, (SR_IMASK | SR_IE)
-    // Get value of __OSGlobalIntMask
-    lui     $t0, %hi(__OSGlobalIntMask)
-    addiu   $t0, %lo(__OSGlobalIntMask)
-    lw      $t3, ($t0)
-    // Bitwise-OR in the disabled CPU bits of __OSGlobalIntMask
-    li      $at, ~0
-    xor     $t0, $t3, $at
-    andi    $t0, $t0, SR_IMASK
-    or      $v0, $v0, $t0
-    // Fetch MI_INTR_MASK_REG
-    lui     $t2, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    lw      $t2, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))($t2)
-    // If there are RCP interrupts masked
-    beqz    $t2, 1f
-     srl    $t1, $t3, RCP_IMASKSHIFT
-    // Bitwise-OR in the disabled RCP bits of __OSGlobalIntMask
-    li      $at, ~0
-    xor     $t1, $t1, $at
-    andi    $t1, $t1, (RCP_IMASK >> RCP_IMASKSHIFT)
-    or      $t2, $t2, $t1
+     /* Extract interrupt enable bits from current SR */
+    MFC0(   t4, C0_SR)
+.set noreorder
+    and     v0, t4, (SR_IMASK | SR_IE)
+     /* Get value of __OSGlobalIntMask */
+    la      t0, __OSGlobalIntMask
+    lw      t3, (t0)
+     /* Bitwise-OR in the disabled CPU bits of __OSGlobalIntMask */
+    xor     t0, t3, ~0
+    and     t0, t0, SR_IMASK
+    or      v0, v0, t0
+     /* Fetch MI_INTR_MASK_REG */
+    lw      t2, PHYS_TO_K1(MI_INTR_MASK_REG)
+     /* If there are RCP interrupts masked */
+    beqz    t2, 1f
+     srl    t1, t3, RCP_IMASKSHIFT
+    /* Bitwise-OR in the disabled RCP bits of __OSGlobalIntMask */
+    xor     t1, t1, ~0
+    and     t1, t1, (RCP_IMASK >> RCP_IMASKSHIFT)
+    or      t2, t2, t1
 1:
-    // Shift the RCP bits to not conflict with the CPU bits
-    sll     $t2, $t2, RCP_IMASKSHIFT
-    // OR the CPU and RCP bits together
-    or      $v0, $v0, $t2
-    // Extract RCP interrupt enable bits from requested mask and mask with __OSGlobalIntMask
-    li      $at, RCP_IMASK
-    and     $t0, $a0, $at
-    and     $t0, $t0, $t3
-    // Convert to a value for MI_INTR_MASK_REG and set it
-    srl     $t0, $t0, (RCP_IMASKSHIFT-1)
-    lui     $t2, %hi(__osRcpImTable)
-    addu    $t2, $t2, $t0
-    lhu     $t2, %lo(__osRcpImTable)($t2)
-    lui     $at, %hi(PHYS_TO_K1(MI_INTR_MASK_REG))
-    sw      $t2, %lo(PHYS_TO_K1(MI_INTR_MASK_REG))($at)
-    // Extract CPU interrupt enable bits from requested mask and mask with __OSGlobalIntMask
-    andi    $t0, $a0, OS_IM_CPU
-    andi    $t1, $t3, SR_IMASK
-    and     $t0, $t0, $t1
-    li      $at, ~SR_IMASK
-    and     $t4, $t4, $at
-    // Bitwise OR in the remaining bits of SR and set new SR
-    or      $t4, $t4, $t0
-    mtc0    $t4, C0_SR
-    nop
-    nop
-    jr      $ra
-     nop
+     /* Shift the RCP bits to not conflict with the CPU bits */
+    sll     t2, t2, RCP_IMASKSHIFT
+     /* OR the CPU and RCP bits together */
+    or      v0, v0, t2
+     /* Extract RCP interrupt enable bits from requested mask and mask with __OSGlobalIntMask */
+    and     t0, a0, RCP_IMASK
+    and     t0, t0, t3
+     /* Convert to a value for MI_INTR_MASK_REG and set it */
+    srl     t0, t0, (RCP_IMASKSHIFT-1)
+    lhu     t2, __osRcpImTable(t0)
+    sw      t2, PHYS_TO_K1(MI_INTR_MASK_REG)
+     /* Extract CPU interrupt enable bits from requested mask and mask with __OSGlobalIntMask */
+    and     t0, a0, OS_IM_CPU
+    and     t1, t3, SR_IMASK
+    and     t0, t0, t1
+    and     t4, t4, ~SR_IMASK
+     /* Bitwise OR in the remaining bits of SR and set new SR */
+    or      t4, t4, t0
+    MTC0(   t4, C0_SR)
+    NOP
+    NOP
+    jr      ra
 END(osSetIntMask)
diff --git a/src/libultra/os/setsr.s b/src/libultra/os/setsr.s
index b754359ea..fb7a1586d 100644
--- a/src/libultra/os/setsr.s
+++ b/src/libultra/os/setsr.s
@@ -1,15 +1,11 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osSetSR)
-    mtc0    $a0, C0_SR
-    nop
-    jr      $ra
-     nop
+    MTC0(   a0, C0_SR)
+    NOP
+    jr      ra
 END(__osSetSR)
diff --git a/src/libultra/os/setwatchlo.s b/src/libultra/os/setwatchlo.s
index aee3ad4d6..962513a48 100644
--- a/src/libultra/os/setwatchlo.s
+++ b/src/libultra/os/setwatchlo.s
@@ -1,15 +1,11 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(__osSetWatchLo)
-    mtc0    $a0, C0_WATCHLO
-    nop
-    jr      $ra
-     nop
+    MTC0(   a0, C0_WATCHLO)
+    NOP
+    jr      ra
 END(__osSetWatchLo)
diff --git a/src/libultra/os/unmaptlball.s b/src/libultra/os/unmaptlball.s
index e1a03b1a2..8cd79984e 100644
--- a/src/libultra/os/unmaptlball.s
+++ b/src/libultra/os/unmaptlball.s
@@ -1,29 +1,25 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(osUnmapTLBAll)
-    mfc0    $t0, C0_ENTRYHI
-    li      $t1, (NTLBENTRIES - 1)
-    li      $t2, (K0BASE & TLBHI_VPN2MASK)
-    mtc0    $t2, C0_ENTRYHI
-    mtc0    $zero, C0_ENTRYLO0
-    mtc0    $zero, C0_ENTRYLO1
+    MFC0(   t0, C0_ENTRYHI)
+    li      t1, (NTLBENTRIES - 1)
+    li      t2, (K0BASE & TLBHI_VPN2MASK)
+    MTC0(   t2, C0_ENTRYHI)
+    MTC0(   zero, C0_ENTRYLO0)
+    MTC0(   zero, C0_ENTRYLO1)
 1:
-    mtc0    $t1, C0_INX
-    nop
-    tlbwi
-    nop
-    nop
-    addi    $t1, $t1, -1
-    bgez    $t1, 1b
-     nop
-    mtc0    $t0, C0_ENTRYHI
-    jr      $ra
-     nop
+    MTC0(   t1, C0_INX)
+    NOP
+    TLBWI
+    NOP
+    NOP
+    addi    t1, t1, -1
+    bgez    t1, 1b
+
+    MTC0(   t0, C0_ENTRYHI)
+    jr      ra
 END(osUnmapTLBAll)
diff --git a/src/libultra/os/writebackdcache.s b/src/libultra/os/writebackdcache.s
index 829f6f4a0..c7207c7e5 100644
--- a/src/libultra/os/writebackdcache.s
+++ b/src/libultra/os/writebackdcache.s
@@ -1,12 +1,8 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 /**
  *  void osWritebackDCache(void* vaddr, s32 nbytes);
@@ -16,45 +12,43 @@
  *  written back.
  */
 LEAF(osWritebackDCache)
-    // If the amount to write back is less than or equal to 0, return immediately
-    blez    $a1, .ret
-     nop
-    // If the amount to write back is as large as or larger than
-    // the data cache size, write back all
-    li      $t3, DCACHE_SIZE
-    sltu    $at, $a1, $t3
-    beqz    $at, .all
-     nop
-    // ensure end address doesn't wrap around and end up smaller
-    // than the start address
-    move    $t0, $a0
-    addu    $t1, $a0, $a1
-    sltu    $at, $t0, $t1
-    beqz    $at, .ret
-     nop
-    // Mask and subtract to align to cache line
-    andi    $t2, $t0, DCACHE_LINEMASK
-    addiu   $t1, $t1, -DCACHE_LINESIZE
-    subu    $t0, $t0, $t2
+    /* If the amount to write back is less than or equal to 0, return immediately */
+    blez    a1, .ret
+
+    /* If the amount to write back is as large as or larger than */
+    /* the data cache size, write back all */
+    li      t3, DCACHE_SIZE
+    bgeu    a1, t3, .all
+
+    /* ensure end address doesn't wrap around and end up smaller */
+    /* than the start address */
+    move    t0, a0
+    addu    t1, a0, a1
+    bgeu    t0, t1, .ret
+
+    /* Mask and subtract to align to cache line */
+    andi    t2, t0, DCACHE_LINEMASK
+    addiu   t1, t1, -DCACHE_LINESIZE
+    subu    t0, t0, t2
 1:
-    cache   (CACH_PD | C_HWB), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 1b
-     addiu  $t0, $t0, DCACHE_LINESIZE
+.set noreorder
+    cache   (CACH_PD | C_HWB), (t0)
+    bltu    t0, t1, 1b
+     addiu  t0, t0, DCACHE_LINESIZE
+.set reorder
 .ret:
-    jr      $ra
-     nop
+    jr      ra
 
-// same as osWritebackDCacheAll in operation
+/* same as osWritebackDCacheAll in operation */
 .all:
-    li      $t0, K0BASE
-    addu    $t1, $t0, $t3
-    addiu   $t1, $t1, -DCACHE_LINESIZE
+    li      t0, K0BASE
+    addu    t1, t0, t3
+    addiu   t1, t1, -DCACHE_LINESIZE
 1:
-    cache   (CACH_PD | C_IWBINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 1b
-     addiu  $t0, DCACHE_LINESIZE
-    jr      $ra
-     nop
+.set noreorder
+    cache   (CACH_PD | C_IWBINV), (t0)
+    bltu    t0, t1, 1b
+     addiu  t0, DCACHE_LINESIZE
+.set reorder
+    jr      ra
 END(osWritebackDCache)
diff --git a/src/libultra/os/writebackdcacheall.s b/src/libultra/os/writebackdcacheall.s
index 54a58dff8..a15ef4554 100644
--- a/src/libultra/os/writebackdcacheall.s
+++ b/src/libultra/os/writebackdcacheall.s
@@ -1,23 +1,19 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "ultra64/R4300.h"
 
-.set noat
-.set noreorder
-
-.section .text
-
-.balign 16
+.text
 
 LEAF(osWritebackDCacheAll)
-    li      $t0, K0BASE
-    li      $t2, DCACHE_SIZE
-    addu    $t1, $t0, $t2
-    addiu   $t1, $t1, -DCACHE_LINESIZE
+    li      t0, K0BASE
+    li      t2, DCACHE_SIZE
+    addu    t1, t0, t2
+    addiu   t1, t1, -DCACHE_LINESIZE
 1:
-    cache   (CACH_PD | C_IWBINV), ($t0)
-    sltu    $at, $t0, $t1
-    bnez    $at, 1b
-     addiu  $t0, DCACHE_LINESIZE
-    jr      $ra
-     nop
+.set noreorder
+    cache   (CACH_PD | C_IWBINV), (t0)
+    bltu    t0, t1, 1b
+     addiu  t0, DCACHE_LINESIZE
+.set reorder
+    jr      ra
 END(osWritebackDCacheAll)
diff --git a/src/makerom/entry.s b/src/makerom/entry.s
index 6be493e6b..0a1233d80 100644
--- a/src/makerom/entry.s
+++ b/src/makerom/entry.s
@@ -1,34 +1,44 @@
 #include "ultra64/asm.h"
+#include "ultra64/regdef.h"
 #include "boot.h"
 
-.set noreorder
+.text
 
-.section .text
-
-.balign 16
-
-LEAF(entrypoint)
-    // Clear boot segment .bss
-    la      $t0, _bootSegmentBssStart
-#ifndef AVOID_UB
-    // UB: li only loads the lower 16 bits of _bootSegmentBssSize when it may be larger than this,
-    // so not all of bss may be cleared if it is too large
-    li      $t1, _bootSegmentBssSize
+#if defined(__sgi) && !defined(AVOID_UB)
+/* IDO assembler workaround: The makerom tool in the N64 SDK was given the bss segment size as a const
+ * literal, and since this literal was < 0x10000 it was loaded in one instruction. We don't have access
+ * to the bss segment size until we link everything so we cannot do the same thing. Instead we must load
+ * only the lower 16 bits of the bss size for matching.
+ * When AVOID_UB is enabled, don't do this and instead load the full symbol value, otherwise not all of
+ * bss may be cleared. */
+#define LOAD_BSS_SIZE(reg) li reg, %half(_bootSegmentBssSize)
 #else
-    la      $t1, _bootSegmentBssSize
+#define LOAD_BSS_SIZE(reg) la reg, _bootSegmentBssSize
 #endif
+
+LEAF(entrypoint)
+    /* Clear boot segment .bss */
+    la      t0, _bootSegmentBssStart
+    LOAD_BSS_SIZE(t1)
 .clear_bss:
-    addi    $t1, $t1, -8
-    sw      $zero, ($t0)
-    sw      $zero, 4($t0)
-    bnez    $t1, .clear_bss
-     addi   $t0, $t0, 8
-    // Set up stack and enter program code
-    lui     $t2, %hi(bootproc)
-    lui     $sp, %hi(sBootThreadStack + BOOT_STACK_SIZE)
-    addiu   $t2, %lo(bootproc)
-    jr      $t2
-     addiu  $sp, %lo(sBootThreadStack + BOOT_STACK_SIZE)
+    sw      zero, 0(t0)
+    sw      zero, 4(t0)
+    addi    t0, t0, 8
+    addi    t1, t1, -8
+    bnez    t1, .clear_bss
+
+    /* Set up stack and enter program code */
+    la      sp, sBootThreadStack + BOOT_STACK_SIZE
+    la      t2, bootproc
+    jr      t2
 END(entrypoint)
 
+#ifdef __GNUC__
+/* Pad to a total size of 0x60 */
 .fill 0x60 - (. - entrypoint)
+#else
+/* IDO can't take absolute differences of symbols.. */
+.repeat (0x60 - 0x34)
+    .byte 0
+.endr
+#endif
diff --git a/src/makerom/ipl3.s b/src/makerom/ipl3.s
deleted file mode 100644
index 45f1c8e6f..000000000
--- a/src/makerom/ipl3.s
+++ /dev/null
@@ -1,4 +0,0 @@
-
-.section .text
-
-.incbin "incbin/ipl3"
author	Tharo <17233964+Thar0@users.noreply.github.com>	2024-12-28 20:18:45 +0000
committer	GitHub <noreply@github.com>	2024-12-28 15:18:45 -0500
commit	7e082f0c4f6b34820b4dbf6285d05adf423c091b (patch)
tree	5b2f1d322eafd4afd6b30109eab12ae36d2b72bf /src
parent	ba6a83533ac3dcbd6c0c70c9857572ed1ef1d009 (diff)