[llvm] VirtRegRewriter: Fix verifier errors after regalloc failures (PR #128280)

[Christudasan Devadasan via llvm-commits]

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@@ -617,9 +620,7 @@ void VirtRegRewriter::rewrite() {
         assert(Register(PhysReg).isPhysical());
 
         RewriteRegs.insert(PhysReg);
-        assert((!MRI->isReserved(PhysReg) ||
-                MF->getProperties().hasProperty(
-                    MachineFunctionProperties::Property::FailedRegAlloc)) &&
+        assert((!MRI->isReserved(PhysReg) || !IsValidAlloc) &&
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cdevadas wrote:

```suggestion
        assert((!MRI->isReserved(PhysReg) || IsFailedAlloc) &&
```

https://github.com/llvm/llvm-project/pull/128280