Enabled SSE2 optimization of GX_TF_CMPR decoder only for x86 builds. It can't compete with the x64 optimized reference C code.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6755 8ced0084-cf51-0410-be5f-012b33b47a6e

1 files changed, 109 insertions, 234 deletions

diff --git a/Source/Core/VideoCommon/Src/TextureDecoder.cpp b/Source/Core/VideoCommon/Src/TextureDecoder.cpp
index eb630cdee2..7e6c168cc7 100644
--- a/Source/Core/VideoCommon/Src/TextureDecoder.cpp
+++ b/Source/Core/VideoCommon/Src/TextureDecoder.cpp
@@ -1707,20 +1707,18 @@ PC_TexFormat TexDecoder_Decode_RGBA(u32 * dst, const u8 * src, int width, int he
 	case GX_TF_CMPR:  // speed critical
 		// The metroid games use this format almost exclusively.
 		{
+#if !defined(_M_X64)
 			// JSD optimized with SSE2 intrinsics.
-			// Produces a ~40% improvement in speed over reference C implementation on an x86 Intel Core 2 Duo
-			// but also a -10% to 0% "improvement" on an x64 AMD Phenom II. Further optimization is required to
-			// ensure that all architectures and CPUs gain benefits.
+			// Produces a 30% improvement for x86 code only.
 			for (int y = 0; y < height; y += 8)
 			{
 				for (int x = 0; x < width; x += 8)
 				{
-					u32 *dst32 = dst + y * width + x;
 					// We handle two DXT blocks simultaneously to take full advantage of SSE2's 128-bit registers.
 					// This is ideal because a single DXT block contains 2 RGBA colors when decoded from their 16-bit.
 					// Two DXT blocks therefore contain 4 RGBA colors to be processed. The processing is parallelizable
 					// at this level, so we do.
-					for (int z = 0; z < 2; ++z, src += sizeof(struct DXTBlock) * 2, dst32 += (width * 4))
+					for (int z = 0; z < 2; ++z, src += sizeof(struct DXTBlock) * 2)
 					{
 						// JSD NOTE: You may see many strange patterns of behavior in the below code, but they
 						// are for performance reasons. Sometimes, calculating what should be obvious hard-coded
@@ -1820,12 +1818,6 @@ PC_TexFormat TexDecoder_Decode_RGBA(u32 * dst, const u8 * src, int width, int he
 							_mm_slli_si128(_mm_srli_si128(rgb31, 4), 8 + 4)
 						);
 
-						// Copy the color arrays from the XMM registers to local variables in RAM:
-						GC_ALIGNED16(u32 colors0A[4]);
-						GC_ALIGNED16(u32 colors0B[4]);
-						_mm_store_si128((__m128i *)colors0A, rgb01230);
-						_mm_store_si128((__m128i *)colors0B, rgb01450);
-
 						// Create an array for color lookups for DXT1 so we can use the 2-bit indices:
 						const __m128i rgb01231 = _mm_or_si128(
 							_mm_or_si128(
@@ -1842,12 +1834,6 @@ PC_TexFormat TexDecoder_Decode_RGBA(u32 * dst, const u8 * src, int width, int he
 							_mm_slli_si128(_mm_srli_si128(rgb31, 8 + 4), 8 + 4)
 						);
 
-						// Copy the color arrays from the XMM registers to aligned local variables in RAM:
-						GC_ALIGNED16(u32 colors1A[4]);
-						GC_ALIGNED16(u32 colors1B[4]);
-						_mm_store_si128((__m128i *)colors1A, rgb01231);
-						_mm_store_si128((__m128i *)colors1B, rgb01451);
-
 						// The #ifdef CHECKs here and below are to compare correctness of output against the reference code.
 						// Don't use them in a normal build.
 #ifdef CHECK
@@ -1867,11 +1853,48 @@ PC_TexFormat TexDecoder_Decode_RGBA(u32 * dst, const u8 * src, int width, int he
 						// the assembly generated was swapping a lot of temporaries to RAM.
 
 						// Compare rgb0 to rgb1:
-						// Each 32-bit word will contain either 0xFFFFFFFF or 0x00000000 for true/false.
-						//const __m128i cmprgb0rgb1 = _mm_cmpgt_epi32(rgb0, rgb1);
-						const __m128i c0cmp = _mm_srli_epi32(_mm_slli_epi32(_mm_srli_epi64(c0, 8), 16), 16);
+
+						//                 rgb1rgb1 rgb0rgb0 rgb1rgb1 rgb0rgb0
+						// c0 example: {0x 5ef05ef0 c003c003 3ff83ff8 e003e003} in BIG ENDIAN
+						// c0cmp contains rgb0 values in 64-bit words in LITTLE ENDIAN
+						// c0cmp:      {0x 00000000 000003c0 00000000 000003e0}
+						// c0shr contains rgb1 values in 64-bit words in LITTLE ENDIAN
+						// c0cmp:      {0x 00000000 0000f05e 00000000 0000f83f}
+
+						__m128i c0cmp = _mm_srli_epi32(_mm_slli_epi32(_mm_srli_epi64(c0, 8), 16), 16);
 						const __m128i c0shr = _mm_srli_epi64(c0cmp, 32);
-						const __m128i cmprgb0rgb1 = _mm_cmpgt_epi32(c0cmp, c0shr);
+						c0cmp = _mm_srli_epi64(_mm_slli_epi64(c0cmp, 48), 48);
+
+#if 0
+						// SSE4 only.
+						const __m128i cmprgb0rgb1 = _mm_cmpgt_epi64(c0cmp, c0shr);
+#else
+						// We need 64-bit words full of 0xFF bytes for comparison masks. cmgt_epi64 would do that but it's only SSE4
+						// so we fake it on SSE2 by shuffling the 32-bit comparison masks to copy the 0xFF bytes to the high 32-bits of
+						// each 64-bit word.
+						__m128i cmprgb0rgb1 = _mm_cmpgt_epi32(c0cmp, c0shr);
+						cmprgb0rgb1 = _mm_shuffle_epi32(cmprgb0rgb1, _MM_SHUFFLE(2, 2, 0, 0));
+#endif
+
+						// Now use the comparison mask from rgb0 > rgb1 to conditionally move colors from
+						// either rgb0123X or rgb0145X:
+						const __m128i cmp0 = _mm_unpacklo_epi64(cmprgb0rgb1, cmprgb0rgb1);
+						const __m128i cmp1 = _mm_unpackhi_epi64(cmprgb0rgb1, cmprgb0rgb1);
+						const __m128i mmcolors0 = _mm_or_si128(
+							_mm_and_si128(cmp0, rgb01230),
+							_mm_andnot_si128(cmp0, rgb01450)
+						);
+						const __m128i mmcolors1 = _mm_or_si128(
+							_mm_and_si128(cmp1, rgb01231),
+							_mm_andnot_si128(cmp1, rgb01451)
+						);
+
+						// Copy the color arrays from the XMM registers to local variables in RAM:
+						GC_ALIGNED16(u32 colors0[4]);
+						GC_ALIGNED16(u32 colors1[4]);
+
+						_mm_store_si128((__m128i *)colors0, mmcolors0);
+						_mm_store_si128((__m128i *)colors1, mmcolors1);
 
 						// Copy the 2-bit indices from each DXT block:
 						GC_ALIGNED16(u32 dxttmp[4]);
@@ -1880,254 +1903,106 @@ PC_TexFormat TexDecoder_Decode_RGBA(u32 * dst, const u8 * src, int width, int he
 						u32 dxt0sel = dxttmp[1];
 						u32 dxt1sel = dxttmp[3];
 
-						// Copy the comparison results:
-						GC_ALIGNED16(u16 cmptmp[8]);
-						_mm_store_si128((__m128i *)cmptmp, cmprgb0rgb1);
-
 						// Per each row written we alternate storing RGBA values from DXT0 and DXT1.
 
 						__m128i *dst128 = (__m128i *)( dst + (y + z*4) * width + x );
 
 						// Row 0:
 						__m128i col0, col1;
-						if (cmptmp[0])
-						{
-							// rgb0a > rgb1a
-							col0 = _mm_set_epi32(
-								colors0A[(dxt0sel >> ((0*8)+0)) & 3],
-								colors0A[(dxt0sel >> ((0*8)+2)) & 3],
-								colors0A[(dxt0sel >> ((0*8)+4)) & 3],
-								colors0A[(dxt0sel >> ((0*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 0), col0);
-#ifdef CHECK
-							assert( memcmp(&(tmp0[0]), dst128 + ((width / 4) * 0), 16) == 0 );
-#endif
-						}
-						else
-						{
-							// rgb0a <= rgb1a
-							col0 = _mm_set_epi32(
-								colors0B[(dxt0sel >> ((0*8)+0)) & 3],
-								colors0B[(dxt0sel >> ((0*8)+2)) & 3],
-								colors0B[(dxt0sel >> ((0*8)+4)) & 3],
-								colors0B[(dxt0sel >> ((0*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 0), col0);
+						col0 = _mm_set_epi32(
+							colors0[(dxt0sel >> ((0*8)+0)) & 3],
+							colors0[(dxt0sel >> ((0*8)+2)) & 3],
+							colors0[(dxt0sel >> ((0*8)+4)) & 3],
+							colors0[(dxt0sel >> ((0*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 0), col0);
 #ifdef CHECK
-							assert( memcmp(&(tmp0[0]), dst128 + ((width / 4) * 0), 16) == 0 );
+						assert( memcmp(&(tmp0[0]), dst128 + ((width / 4) * 0), 16) == 0 );
 #endif
-						}
 
-						if (cmptmp[4])
-						{
-							// (rgb0b > rgb1b)
-							col1 = _mm_set_epi32(
-								colors1A[(dxt1sel >> ((0*8)+0)) & 3],
-								colors1A[(dxt1sel >> ((0*8)+2)) & 3],
-								colors1A[(dxt1sel >> ((0*8)+4)) & 3],
-								colors1A[(dxt1sel >> ((0*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 0) + 1, col1);
-#ifdef CHECK
-							assert( memcmp(&(tmp1[0]), dst128 + ((width / 4) * 0) + 1, 16) == 0 );
-#endif
-						}
-						else
-						{
-							// (rgb0b <= rgb1b)
-							col1 = _mm_set_epi32(
-								colors1B[(dxt1sel >> ((0*8)+0)) & 3],
-								colors1B[(dxt1sel >> ((0*8)+2)) & 3],
-								colors1B[(dxt1sel >> ((0*8)+4)) & 3],
-								colors1B[(dxt1sel >> ((0*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 0) + 1, col1);
+						col1 = _mm_set_epi32(
+							colors1[(dxt1sel >> ((0*8)+0)) & 3],
+							colors1[(dxt1sel >> ((0*8)+2)) & 3],
+							colors1[(dxt1sel >> ((0*8)+4)) & 3],
+							colors1[(dxt1sel >> ((0*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 0) + 1, col1);
 #ifdef CHECK
-							assert( memcmp(&(tmp1[0]), dst128 + ((width / 4) * 0) + 1, 16) == 0 );
+						assert( memcmp(&(tmp1[0]), dst128 + ((width / 4) * 0) + 1, 16) == 0 );
 #endif
-						}
 
 						// Row 1:
-						if (cmptmp[0])
-						{
-							// rgb0a > rgb1a
-							col0 = _mm_set_epi32(
-								colors0A[(dxt0sel >> ((1*8)+0)) & 3],
-								colors0A[(dxt0sel >> ((1*8)+2)) & 3],
-								colors0A[(dxt0sel >> ((1*8)+4)) & 3],
-								colors0A[(dxt0sel >> ((1*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 1), col0);
-#ifdef CHECK
-							assert( memcmp(&(tmp0[1]), dst128 + ((width / 4) * 1), 16) == 0 );
-#endif
-						}
-						else
-						{
-							// rgb0a <= rgb1a
-							col0 = _mm_set_epi32(
-								colors0B[(dxt0sel >> ((1*8)+0)) & 3],
-								colors0B[(dxt0sel >> ((1*8)+2)) & 3],
-								colors0B[(dxt0sel >> ((1*8)+4)) & 3],
-								colors0B[(dxt0sel >> ((1*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 1), col0);
+						col0 = _mm_set_epi32(
+							colors0[(dxt0sel >> ((1*8)+0)) & 3],
+							colors0[(dxt0sel >> ((1*8)+2)) & 3],
+							colors0[(dxt0sel >> ((1*8)+4)) & 3],
+							colors0[(dxt0sel >> ((1*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 1), col0);
 #ifdef CHECK
-							assert( memcmp(&(tmp0[1]), dst128 + ((width / 4) * 1), 16) == 0 );
+						assert( memcmp(&(tmp0[1]), dst128 + ((width / 4) * 1), 16) == 0 );
 #endif
-						}
 
-						if (cmptmp[4])
-						{
-							// (rgb0b > rgb1b)
-							col1 = _mm_set_epi32(
-								colors1A[(dxt1sel >> ((1*8)+0)) & 3],
-								colors1A[(dxt1sel >> ((1*8)+2)) & 3],
-								colors1A[(dxt1sel >> ((1*8)+4)) & 3],
-								colors1A[(dxt1sel >> ((1*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 1) + 1, col1);
-#ifdef CHECK
-							assert( memcmp(&(tmp1[1]), dst128 + ((width / 4) * 1) + 1, 16) == 0 );
-#endif
-						}
-						else
-						{
-							// (rgb0b <= rgb1b)
-							col1 = _mm_set_epi32(
-								colors1B[(dxt1sel >> ((1*8)+0)) & 3],
-								colors1B[(dxt1sel >> ((1*8)+2)) & 3],
-								colors1B[(dxt1sel >> ((1*8)+4)) & 3],
-								colors1B[(dxt1sel >> ((1*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 1) + 1, col1);
+						col1 = _mm_set_epi32(
+							colors1[(dxt1sel >> ((1*8)+0)) & 3],
+							colors1[(dxt1sel >> ((1*8)+2)) & 3],
+							colors1[(dxt1sel >> ((1*8)+4)) & 3],
+							colors1[(dxt1sel >> ((1*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 1) + 1, col1);
 #ifdef CHECK
-							assert( memcmp(&(tmp1[1]), dst128 + ((width / 4) * 1) + 1, 16) == 0 );
+						assert( memcmp(&(tmp1[1]), dst128 + ((width / 4) * 1) + 1, 16) == 0 );
 #endif
-						}
 
 						// Row 2:
-						if (cmptmp[0])
-						{
-							// rgb0a > rgb1a
-							col0 = _mm_set_epi32(
-								colors0A[(dxt0sel >> ((2*8)+0)) & 3],
-								colors0A[(dxt0sel >> ((2*8)+2)) & 3],
-								colors0A[(dxt0sel >> ((2*8)+4)) & 3],
-								colors0A[(dxt0sel >> ((2*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 2), col0);
-#ifdef CHECK
-							assert( memcmp(&(tmp0[2]), dst128 + ((width / 4) * 2), 16) == 0 );
-#endif
-						}
-						else
-						{
-							// rgb0a <= rgb1a
-							col0 = _mm_set_epi32(
-								colors0B[(dxt0sel >> ((2*8)+0)) & 3],
-								colors0B[(dxt0sel >> ((2*8)+2)) & 3],
-								colors0B[(dxt0sel >> ((2*8)+4)) & 3],
-								colors0B[(dxt0sel >> ((2*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 2), col0);
+						col0 = _mm_set_epi32(
+							colors0[(dxt0sel >> ((2*8)+0)) & 3],
+							colors0[(dxt0sel >> ((2*8)+2)) & 3],
+							colors0[(dxt0sel >> ((2*8)+4)) & 3],
+							colors0[(dxt0sel >> ((2*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 2), col0);
 #ifdef CHECK
-							assert( memcmp(&(tmp0[2]), dst128 + ((width / 4) * 2), 16) == 0 );
+						assert( memcmp(&(tmp0[2]), dst128 + ((width / 4) * 2), 16) == 0 );
 #endif
-						}
 
-						if (cmptmp[4])
-						{
-							// (rgb0b > rgb1b)
-							col1 = _mm_set_epi32(
-								colors1A[(dxt1sel >> ((2*8)+0)) & 3],
-								colors1A[(dxt1sel >> ((2*8)+2)) & 3],
-								colors1A[(dxt1sel >> ((2*8)+4)) & 3],
-								colors1A[(dxt1sel >> ((2*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 2) + 1, col1);
-#ifdef CHECK
-							assert( memcmp(&(tmp1[2]), dst128 + ((width / 4) * 2) + 1, 16) == 0 );
-#endif
-						}
-						else
-						{
-							// (rgb0b <= rgb1b)
-							col1 = _mm_set_epi32(
-								colors1B[(dxt1sel >> ((2*8)+0)) & 3],
-								colors1B[(dxt1sel >> ((2*8)+2)) & 3],
-								colors1B[(dxt1sel >> ((2*8)+4)) & 3],
-								colors1B[(dxt1sel >> ((2*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 2) + 1, col1);
+						col1 = _mm_set_epi32(
+							colors1[(dxt1sel >> ((2*8)+0)) & 3],
+							colors1[(dxt1sel >> ((2*8)+2)) & 3],
+							colors1[(dxt1sel >> ((2*8)+4)) & 3],
+							colors1[(dxt1sel >> ((2*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 2) + 1, col1);
 #ifdef CHECK
-							assert( memcmp(&(tmp1[2]), dst128 + ((width / 4) * 2) + 1, 16) == 0 );
+						assert( memcmp(&(tmp1[2]), dst128 + ((width / 4) * 2) + 1, 16) == 0 );
 #endif
-						}
 
 						// Row 3:
-						if (cmptmp[0])
-						{
-							// rgb0a > rgb1a
-							col0 = _mm_set_epi32(
-								colors0A[(dxt0sel >> ((3*8)+0)) & 3],
-								colors0A[(dxt0sel >> ((3*8)+2)) & 3],
-								colors0A[(dxt0sel >> ((3*8)+4)) & 3],
-								colors0A[(dxt0sel >> ((3*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 3), col0);
-#ifdef CHECK
-							assert( memcmp(&(tmp0[3]), dst128 + ((width / 4) * 3), 16) == 0 );
-#endif
-						}
-						else
-						{
-							// rgb0a <= rgb1a
-							col0 = _mm_set_epi32(
-								colors0B[(dxt0sel >> ((3*8)+0)) & 3],
-								colors0B[(dxt0sel >> ((3*8)+2)) & 3],
-								colors0B[(dxt0sel >> ((3*8)+4)) & 3],
-								colors0B[(dxt0sel >> ((3*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 3), col0);
+						col0 = _mm_set_epi32(
+							colors0[(dxt0sel >> ((3*8)+0)) & 3],
+							colors0[(dxt0sel >> ((3*8)+2)) & 3],
+							colors0[(dxt0sel >> ((3*8)+4)) & 3],
+							colors0[(dxt0sel >> ((3*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 3), col0);
 #ifdef CHECK
-							assert( memcmp(&(tmp0[3]), dst128 + ((width / 4) * 3), 16) == 0 );
+						assert( memcmp(&(tmp0[3]), dst128 + ((width / 4) * 3), 16) == 0 );
 #endif
-						}
 
-						if (cmptmp[4])
-						{
-							// (rgb0b > rgb1b)
-							col1 = _mm_set_epi32(
-								colors1A[(dxt1sel >> ((3*8)+0)) & 3],
-								colors1A[(dxt1sel >> ((3*8)+2)) & 3],
-								colors1A[(dxt1sel >> ((3*8)+4)) & 3],
-								colors1A[(dxt1sel >> ((3*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 3) + 1, col1);
-#ifdef CHECK
-							assert( memcmp(&(tmp1[3]), dst128 + ((width / 4) * 3) + 1, 16) == 0 );
-#endif
-						}
-						else
-						{
-							// (rgb0b <= rgb1b)
-							col1 = _mm_set_epi32(
-								colors1B[(dxt1sel >> ((3*8)+0)) & 3],
-								colors1B[(dxt1sel >> ((3*8)+2)) & 3],
-								colors1B[(dxt1sel >> ((3*8)+4)) & 3],
-								colors1B[(dxt1sel >> ((3*8)+6)) & 3]
-							);
-							_mm_store_si128(dst128 + ((width / 4) * 3) + 1, col1);
+						col1 = _mm_set_epi32(
+							colors1[(dxt1sel >> ((3*8)+0)) & 3],
+							colors1[(dxt1sel >> ((3*8)+2)) & 3],
+							colors1[(dxt1sel >> ((3*8)+4)) & 3],
+							colors1[(dxt1sel >> ((3*8)+6)) & 3]
+						);
+						_mm_store_si128(dst128 + ((width / 4) * 3) + 1, col1);
 #ifdef CHECK
-							assert( memcmp(&(tmp1[3]), dst128 + ((width / 4) * 3) + 1, 16) == 0 );
+						assert( memcmp(&(tmp1[3]), dst128 + ((width / 4) * 3) + 1, 16) == 0 );
 #endif
-						}
 					}
 				}
 			}
-#if 0
+#else
 			for (int y = 0; y < height; y += 8)
 			{
 				for (int x = 0; x < width; x += 8)