[llvm] [CGP] Fix missing sign extension for base offset in optimizeMemoryInst (PR #161377)

[Nikita Popov via llvm-commits]

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@@ -6100,7 +6100,7 @@ bool CodeGenPrepare::optimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
 
       // Add in the Base Offset if present.
       if (AddrMode.BaseOffs) {
-        Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
+        Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs, true);
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nikic wrote:

```suggestion
        Value *V = ConstantInt::getSigned(IntPtrTy, AddrMode.BaseOffs);
```

https://github.com/llvm/llvm-project/pull/161377