[llvm] [SCCP] Consider provenance when propagating constant ptrs (PR #160083)

[Nikita Popov via llvm-commits]

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@@ -82,6 +83,26 @@ bool SCCPSolver::tryToReplaceWithConstant(Value *V) {
     return false;
   }
 
+  // Perform constant pointer propagation as long as assuming PredicateInfo
+  // derived equality between the two holds, and their provenance is the same.
+  if (auto *I = dyn_cast<Instruction>(V); I && I->getType()->isPointerTy()) {
+    if (getPredicateInfoFor(I)) {
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nikic wrote:

Won't think not work if there any intermediate copies of the value? Like through a phi/select or in the IPSCCP case a function return value etc.

https://github.com/llvm/llvm-project/pull/160083