[llvm] [SPIR-V] Fix an undefined behaviour in the SPIRV emit-intrinsics pass (PR #123620)

[Vyacheslav Levytskyy via llvm-commits]

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@@ -2475,8 +2475,10 @@ void SPIRVEmitIntrinsics::parseFunDeclarations(Module &M) {
     if (DemangledName.empty())
       continue;
     // allow only OpGroupAsyncCopy use case at the moment
-    auto [Grp, Opcode, ExtNo] =
-        SPIRV::mapBuiltinToOpcode(DemangledName, InstrSet);
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VyacheslavLevytskyy wrote:

Not necessarily, it is in use in one more piece of the code in deduceOperandElementTypeCalledFunction(). However, it may make sense indeed, because it's the only use of it, so caching improves nothing.

https://github.com/llvm/llvm-project/pull/123620