[llvm] [Uniformity] Avoid marking all PHIs as divergent in join blocks (PR #157808)

[Jay Foad via llvm-commits]

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@@ -68,6 +69,23 @@ bool SSAContext::isConstantOrUndefValuePhi(const Instruction &Instr) {
   return false;
 }
 
+template <>
+void SSAContext::getPhiInputs(
+    const Instruction &Instr, SmallVectorImpl<const Value *> &Values,
+    SmallVectorImpl<const BasicBlock *> &Blocks) const {
+  if (auto *Phi = dyn_cast<PHINode>(&Instr)) {
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jayfoad wrote:

Same here, Instr must be a PHINode

https://github.com/llvm/llvm-project/pull/157808