[llvm] [AMDGPU] Extend promotion of alloca to vectors (PR #127973)

[Pierre van Houtryve via llvm-commits]

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@@ -310,12 +322,17 @@ bool AMDGPUPromoteAllocaImpl::run(Function &F, bool PromoteToLDS) {
 
   bool SufficientLDS = PromoteToLDS ? hasSufficientLocalMem(F) : false;
 
-  // Use up to 1/4 of available register budget for vectorization.
-  // FIXME: Increase the limit for whole function budgets? Perhaps x2?
+  const unsigned VGPRRatio =
+      PromoteAllocaToVectorVGPRRatio.getNumOccurrences()
+          ? PromoteAllocaToVectorVGPRRatio
+          : F.getFnAttributeAsParsedInteger(
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Pierre-vh wrote:

No, I mean outlining `F.getFnAttributeAsParsedInteger(...)` into a variable and reusing the variable after the colon, instead of having  3 lines of function call nested inside a ternary 

https://github.com/llvm/llvm-project/pull/127973