JitArm64_Integer: Merge subfx and subfcx

The optimizations for subfcx introduced in #13852 also apply to subfx.
Rather than duplicating the logic, we merge the handlers, like we did
in #10120 for x86.

3 files changed, 22 insertions, 30 deletions

diff --git a/Source/Core/Core/PowerPC/JitArm64/Jit.h b/Source/Core/Core/PowerPC/JitArm64/Jit.h
index e98f950d42..5fd25d51d2 100644
--- a/Source/Core/Core/PowerPC/JitArm64/Jit.h
+++ b/Source/Core/Core/PowerPC/JitArm64/Jit.h
@@ -114,7 +114,6 @@ public:
   void rlwimix(UGeckoInstruction inst);
   void subfex(UGeckoInstruction inst);
   void subfzex(UGeckoInstruction inst);
-  void subfcx(UGeckoInstruction inst);
   void subfic(UGeckoInstruction inst);
   void addex(UGeckoInstruction inst);
   void divwux(UGeckoInstruction inst);
diff --git a/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp b/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp
index cd8b00d49f..e82db40756 100644
--- a/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp
+++ b/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp
@@ -18,15 +18,18 @@
 using namespace Arm64Gen;
 using namespace JitCommon;
 
-#define CARRY_IF_NEEDED(inst_without_carry, inst_with_carry, ...)                                  \
+#define CARRY_IF_NEEDED_COND(carry, inst_without_carry, inst_with_carry, ...)                      \
   do                                                                                               \
   {                                                                                                \
-    if (js.op->wantsCA)                                                                            \
+    if ((carry) && js.op->wantsCA)                                                                 \
       inst_with_carry(__VA_ARGS__);                                                                \
     else                                                                                           \
       inst_without_carry(__VA_ARGS__);                                                             \
   } while (0)
 
+#define CARRY_IF_NEEDED(inst_without_carry, inst_with_carry, ...)                                  \
+  CARRY_IF_NEEDED_COND(true, inst_without_carry, inst_with_carry, __VA_ARGS__)
+
 void JitArm64::ComputeRC0(ARM64Reg reg)
 {
   gpr.BindCRToRegister(0, false);
@@ -1114,20 +1117,6 @@ void JitArm64::addzex(UGeckoInstruction inst)
     ComputeRC0(gpr.R(d));
 }
 
-void JitArm64::subfx(UGeckoInstruction inst)
-{
-  INSTRUCTION_START
-  JITDISABLE(bJITIntegerOff);
-  FALLBACK_IF(inst.OE);
-
-  int a = inst.RA, b = inst.RB, d = inst.RD;
-
-  gpr.BindToRegister(d, d == a || d == b);
-  SUB(gpr.R(d), gpr.R(b), gpr.R(a));
-  if (inst.Rc)
-    ComputeRC0(gpr.R(d));
-}
-
 void JitArm64::subfex(UGeckoInstruction inst)
 {
   INSTRUCTION_START
@@ -1259,13 +1248,14 @@ void JitArm64::subfex(UGeckoInstruction inst)
     ComputeRC0(gpr.R(d));
 }
 
-void JitArm64::subfcx(UGeckoInstruction inst)
+void JitArm64::subfx(UGeckoInstruction inst)
 {
   INSTRUCTION_START
   JITDISABLE(bJITIntegerOff);
   FALLBACK_IF(inst.OE);
 
-  int a = inst.RA, b = inst.RB, d = inst.RD;
+  const int a = inst.RA, b = inst.RB, d = inst.RD;
+  const bool carry = !(inst.SUBOP10 & (1 << 5));
 
   if (gpr.IsImm(a))
   {
@@ -1278,7 +1268,8 @@ void JitArm64::subfcx(UGeckoInstruction inst)
         gpr.BindToRegister(d, false);
         MOV(gpr.R(d), gpr.R(b));
       }
-      ComputeCarry(true);
+      if (carry)
+        ComputeCarry(true);
       if (inst.Rc)
         ComputeRC0(gpr.R(d));
       return;
@@ -1289,8 +1280,10 @@ void JitArm64::subfcx(UGeckoInstruction inst)
     if (low_12 || high_12)
     {
       gpr.BindToRegister(d, d == b);
-      CARRY_IF_NEEDED(SUB, SUBS, gpr.R(d), gpr.R(b), high_12 ? imm >> 12 : imm, high_12);
-      ComputeCarry();
+      CARRY_IF_NEEDED_COND(carry, SUB, SUBS, gpr.R(d), gpr.R(b), high_12 ? imm >> 12 : imm,
+                           high_12);
+      if (carry)
+        ComputeCarry();
       if (inst.Rc)
         ComputeRC0(gpr.R(d));
       return;
@@ -1300,8 +1293,9 @@ void JitArm64::subfcx(UGeckoInstruction inst)
   if (gpr.IsImm(b, 0))
   {
     gpr.BindToRegister(d, d == a);
-    CARRY_IF_NEEDED(NEG, NEGS, gpr.R(d), gpr.R(a));
-    ComputeCarry();
+    CARRY_IF_NEEDED_COND(carry, NEG, NEGS, gpr.R(d), gpr.R(a));
+    if (carry)
+      ComputeCarry();
     if (inst.Rc)
       ComputeRC0(gpr.R(d));
     return;
@@ -1310,10 +1304,9 @@ void JitArm64::subfcx(UGeckoInstruction inst)
   gpr.BindToRegister(d, d == a || d == b);
 
   // d = b - a
-  CARRY_IF_NEEDED(SUB, SUBS, gpr.R(d), gpr.R(b), gpr.R(a));
-
-  ComputeCarry();
-
+  CARRY_IF_NEEDED_COND(carry, SUB, SUBS, gpr.R(d), gpr.R(b), gpr.R(a));
+  if (carry)
+    ComputeCarry();
   if (inst.Rc)
     ComputeRC0(gpr.R(d));
 }
diff --git a/Source/Core/Core/PowerPC/JitArm64/JitArm64_Tables.cpp b/Source/Core/Core/PowerPC/JitArm64/JitArm64_Tables.cpp
index eb97db9b91..17b2030e25 100644
--- a/Source/Core/Core/PowerPC/JitArm64/JitArm64_Tables.cpp
+++ b/Source/Core/Core/PowerPC/JitArm64/JitArm64_Tables.cpp
@@ -172,8 +172,8 @@ constexpr std::array<JitArm64OpTemplate, 107> s_table31{{
     {616, &JitArm64::negx},     // negox
     {40, &JitArm64::subfx},     // subfx
     {552, &JitArm64::subfx},    // subfox
-    {8, &JitArm64::subfcx},     // subfcx
-    {520, &JitArm64::subfcx},   // subfcox
+    {8, &JitArm64::subfx},      // subfcx
+    {520, &JitArm64::subfx},    // subfcox
     {136, &JitArm64::subfex},   // subfex
     {648, &JitArm64::subfex},   // subfeox
     {232, &JitArm64::subfex},   // subfmex