[llvm] Add support for x87 registers on GISel register selection (PR #83528)

[Matt Arsenault via llvm-commits]

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@@ -234,7 +250,7 @@ X86RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
     (void)Size;
     assert((Size == 32 || Size == 64) && "Unsupported size for G_FCMP");
 
-    auto FpRegBank = getPartialMappingIdx(Ty1, /* isFP */ true);
+    auto FpRegBank = getPartialMappingIdx(MI, Ty1, /* isFP */ true);
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arsenm wrote:

```suggestion
    auto FpRegBank = getPartialMappingIdx(MI, Ty1, /* isFP= */ true);
```

https://github.com/llvm/llvm-project/pull/83528