[llvm] [AMDGPU][Attributor] Make `AAAMDFlatWorkGroupSize` honor existing attribute (PR #114357)

[Shilei Tian via llvm-commits]

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@@ -144,6 +144,20 @@ static bool funcRequiresHostcallPtr(const Function &F) {
 }
 
 namespace {
+
+std::optional<std::pair<unsigned, unsigned>> static parseRangeAttribute(
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shiltian wrote:

> We should probably make this an IR verifier check

Yes, that is definitely a good idea.

https://github.com/llvm/llvm-project/pull/114357