[llvm] [SPIRV] Audit `select` Result in SPIRVInstructionSelector (PR #115193)

[Sarah Spall via llvm-commits]

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@@ -1229,17 +1244,26 @@ bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
     const MachineMemOperand *MemOp = *I.memoperands_begin();
     unsigned Scope = static_cast<uint32_t>(getMemScope(
         GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
-    ScopeReg = buildI32Constant(Scope, I);
+    auto ScopeConstant = buildI32Constant(Scope, I);
+    ScopeReg = ScopeConstant.first;
+    Result &= ScopeConstant.second;
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spall wrote:

ditto

https://github.com/llvm/llvm-project/pull/115193