[llvm] AMDGPU/PromoteAlloca: Refactor into analysis / commit phases (PR #170512)

[Nicolai Hähnle via llvm-commits]

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@@ -933,21 +1010,22 @@ bool AMDGPUPromoteAllocaImpl::tryPromoteAllocaToVector(AllocaInst &Alloca) {
         return RejectUser(Inst, "mem transfer inst length is non-constant or "
                                 "not a multiple of the vector element size");
 
-      if (TransferInfo.try_emplace(TransferInst).second) {
-        DeferredInsts.push_back(Inst);
-        WorkList.push_back(Inst);
-      }
-
       auto getPointerIndexOfAlloca = [&](Value *Ptr) -> ConstantInt * {
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nhaehnle wrote:

Renaming to `getConstIndexIntoAlloca` ("of" feels like the wrong preposition here)

https://github.com/llvm/llvm-project/pull/170512