[llvm] [VirtRegMap] Store MCRegister in Virt2PhysMap. (PR #108775)

[Craig Topper via llvm-commits]

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@@ -49,7 +48,7 @@ class TargetInstrInfo;
     /// it; even spilled virtual registers (the register mapped to a
     /// spilled register is the temporary used to load it from the
     /// stack).
-    IndexedMap<Register, VirtReg2IndexFunctor> Virt2PhysMap;
+    IndexedMap<MCRegister, VirtReg2IndexFunctor> Virt2PhysMap;
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topperc wrote:

The Key is determined by the `argument_type` field in `VirtReg2IndexFunctor`.

https://github.com/llvm/llvm-project/pull/108775