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Jit64: mtfsfx - Optimized masking 

The masking logic can be eliminated when the mask is known to be all
ones. This case is very common.

Before:
66 48 0F 7E F0       movq        rax,xmm6
8B 55 5C             mov         edx,dword ptr [rbp+5Ch]
83 E0 FF             and         eax,0FFFFFFFFh
83 E2 00             and         edx,0
0B C2                or          eax,edx
89 45 5C             mov         dword ptr [rbp+5Ch],eax
48 8D 15 C3 3C FE 01 lea         rdx,[19520020h]
83 E0 07             and         eax,7
0F AE 14 82          ldmxcsr     dword ptr [rdx+rax*4]

After:
66 48 0F 7E F0       movq        rax,xmm6
89 45 5C             mov         dword ptr [rbp+5Ch],eax
48 8D 15 2A D1 FD 01 lea         rdx,[19440000h]
83 E0 07             and         eax,7
0F AE 14 82          ldmxcsr     dword ptr [rdx+rax*4]
This commit is contained in:
Sintendo 2021-06-26 16:46:09 +02:00
parent c77a5f7e32
commit 7de4623d48
1 changed files with 7 additions and 4 deletions
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11
Source/Core/Core/PowerPC/Jit64/Jit_SystemRegisters.cpp
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@ -792,10 +792,13 @@ void Jit64::mtfsfx(UGeckoInstruction inst)
else
MOV(32, R(RSCRATCH), Rb);
MOV(32, R(RSCRATCH2), PPCSTATE(fpscr));
AND(32, R(RSCRATCH), Imm32(mask));
AND(32, R(RSCRATCH2), Imm32(~mask));
OR(32, R(RSCRATCH), R(RSCRATCH2));
if (mask != 0xFFFFFFFF)
{
MOV(32, R(RSCRATCH2), PPCSTATE(fpscr));
AND(32, R(RSCRATCH), Imm32(mask));
AND(32, R(RSCRATCH2), Imm32(~mask));
OR(32, R(RSCRATCH), R(RSCRATCH2));
}
MOV(32, PPCSTATE(fpscr), R(RSCRATCH));
if (inst.FM & 1)