[llvm] Limit Alloca->LDS promotion based on speculations as to eventual register pressure (PR #152814)

[Patrick Simmons via llvm-commits]

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@@ -100,6 +106,14 @@ class AMDGPUPromoteAllocaImpl {
   unsigned VGPRBudgetRatio;
   unsigned MaxVectorRegs;
 
+  std::unordered_map<BasicBlock *, std::unordered_set<Instruction *>>
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linuxrocks123 wrote:

That may perform slightly better, but it would be harder to read.  Perhaps it would be possible to encapsulate this algorithm into a set data structure somehow.

https://github.com/llvm/llvm-project/pull/152814