Jit_Integer: Handle NOP case for xori and xoris

Like ori and oris, xori and xoris can also be used to introduce a NOP. In that case, just don't do anything.
dolphin-emu · Mar 23, 2018 · fc16a78 · fc16a78
1 parent 007f9e5
commit fc16a78
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Showing 2 changed files with 21 additions and 6 deletions.
diff --git a/Source/Core/Core/PowerPC/Jit64/Jit_Integer.cpp b/Source/Core/Core/PowerPC/Jit64/Jit_Integer.cpp
@@ -326,11 +326,19 @@ void Jit64::reg_imm(UGeckoInstruction inst)
     regimmop(a, s, true, inst.UIMM << 16, And, &XEmitter::AND, true);
     break;
   case 26:  // xori
-    regimmop(a, s, true, inst.UIMM, Xor, &XEmitter::XOR, false);
-    break;
   case 27:  // xoris
-    regimmop(a, s, true, inst.UIMM << 16, Xor, &XEmitter::XOR, false);
+  {
+    if (s == a && inst.UIMM == 0)
+    {
+      // Make the nop visible in the generated code.
+      NOP();
+      return;
+    }
+
+    const u32 immediate = inst.OPCD == 26 ? inst.UIMM : inst.UIMM << 16;
+    regimmop(a, s, true, immediate, Xor, &XEmitter::XOR, false);
     break;
+  }
   case 12:  // addic
     regimmop(d, a, false, (u32)(s32)inst.SIMM_16, Add, &XEmitter::ADD, false, true);
     break;

diff --git a/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp b/Source/Core/Core/PowerPC/JitArm64/JitArm64_Integer.cpp
@@ -142,12 +142,19 @@ void JitArm64::arith_imm(UGeckoInstruction inst)
     reg_imm(a, s, inst.UIMM << 16, BitAND, &ARM64XEmitter::ANDI2R, true);
     break;
   case 26:  // xori
-    reg_imm(a, s, inst.UIMM, BitXOR, &ARM64XEmitter::EORI2R);
-    break;
   case 27:  // xoris
-    reg_imm(a, s, inst.UIMM << 16, BitXOR, &ARM64XEmitter::EORI2R);
+  {
+    if (a == s && inst.UIMM == 0)
+    {
+      // NOP
+      return;
+    }
+
+    const u32 immediate = inst.OPCD == 26 ? inst.UIMM : inst.UIMM << 16;
+    reg_imm(a, s, immediate, BitXOR, &ARM64XEmitter::EORI2R);
     break;
   }
+  }
 }
 
 void JitArm64::addix(UGeckoInstruction inst)