[llvm] [LLVM] New NoDivergenceSource function attribute (PR #111832)

[Jay Foad via llvm-commits]

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@@ -32,7 +32,10 @@ bool llvm::GenericUniformityAnalysisImpl<SSAContext>::markDefsDivergent(
 
 template <> void llvm::GenericUniformityAnalysisImpl<SSAContext>::initialize() {
   for (auto &I : instructions(F)) {
-    if (TTI->isSourceOfDivergence(&I))
+    bool NoDivergenceSource = false;
+    if (auto Call = dyn_cast<CallBase>(&I))
+      NoDivergenceSource = Call->hasFnAttr(Attribute::NoDivergenceSource);
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jayfoad wrote:

Would it make more sense to check for calls in `TargetTransformInfo::isSourceOfDivergence` before it calls into `TTIImpl`?

https://github.com/llvm/llvm-project/pull/111832