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[x64] Explicitly handle AND_NOT dest == src1

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This addresses a JIT-issue in the case that the `src1` and `dest`
register are both the same. This issue only happens in the "generic"
x86 path but not in the BMI1-accelerated path.

Thanks Rick for the extensive debugging help.

When `src1` and `dest` were the same, then the `addc` instruction at
`82099A08` in title `584108FF` might emit the following assembly:
```
.text:82099A08                 andc      r11, r10, r11
  |
  | Jitted
  |
  V
00000000A0011B15  mov         rbx,r10
00000000A0011B18  not         rbx
00000000A0011B1B  and         rbx,rbx
```

This was due to the src1 operand and the destination register being the
same, which used to call the "else" case in the x64 emitter when it
needs to be handled explicitly due to register aliasing/allocation.

Addresses issue #1945
This commit is contained in:
Wunkolo 2022-01-10 13:37:19 -08:00 committed by Rick Gibbed
parent 975eadf17e
commit 37aa3d129c
1 changed files with 5 additions and 0 deletions
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5
src/xenia/cpu/backend/x64/x64_sequences.cc
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@ -2688,6 +2688,11 @@ void EmitAndNotXX(X64Emitter& e, const ARGS& i) {
if (i.dest == i.src2) {
e.not_(i.dest);
e.and_(i.dest, i.src1);
} else if (i.dest == i.src1) {
auto temp = GetTempReg<typename decltype(i.dest)::reg_type>(e);
e.mov(temp, i.src2);
e.not_(temp);
e.and_(i.dest, temp);
} else {
e.mov(i.dest, i.src2);
e.not_(i.dest);