commit 980a3aa9834a886b3c68826d7e8a46984d715516
author Nikita Popov <npopov@redhat.com> Fri Sep 29 11:09:44 2023 +0200
committer Copybara-Service <copybara-worker@google.com> Fri Sep 29 02:16:19 2023 -0700
tree 10e34d755dd7c658dfddf1e2ff422cd4c08725b4
parent 8db0c6af8c7c0c4286f33fe6cbe3d8c70bce7ab0

[JumpThreading] Avoid use of ConstantExpr::getCast()

Use the constant folding API instead.

GitOrigin-RevId: 5cacf4e688aafbc59f101f0ba190b31fa2234928

lib/Transforms/Scalar/JumpThreading.cpp

diff --git a/lib/Transforms/Scalar/JumpThreading.cpp b/lib/Transforms/Scalar/JumpThreading.cpp
index 6c1a1db..ed69f19 100644
--- a/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/lib/Transforms/Scalar/JumpThreading.cpp
@@ -568,6 +568,8 @@
     Value *V, BasicBlock *BB, PredValueInfo &Result,
     ConstantPreference Preference, DenseSet<Value *> &RecursionSet,
     Instruction *CxtI) {
+  const DataLayout &DL = BB->getModule()->getDataLayout();
+
   // This method walks up use-def chains recursively.  Because of this, we could
   // get into an infinite loop going around loops in the use-def chain.  To
   // prevent this, keep track of what (value, block) pairs we've already visited
@@ -635,16 +637,19 @@
   // Handle Cast instructions.
   if (CastInst *CI = dyn_cast<CastInst>(I)) {
     Value *Source = CI->getOperand(0);
-    computeValueKnownInPredecessorsImpl(Source, BB, Result, Preference,
+    PredValueInfoTy Vals;
+    computeValueKnownInPredecessorsImpl(Source, BB, Vals, Preference,
                                         RecursionSet, CxtI);
-    if (Result.empty())
+    if (Vals.empty())
       return false;
 
     // Convert the known values.
-    for (auto &R : Result)
-      R.first = ConstantExpr::getCast(CI->getOpcode(), R.first, CI->getType());
+    for (auto &Val : Vals)
+      if (Constant *Folded = ConstantFoldCastOperand(CI->getOpcode(), Val.first,
+                                                     CI->getType(), DL))
+        Result.emplace_back(Folded, Val.second);
 
-    return true;
+    return !Result.empty();
   }
 
   if (FreezeInst *FI = dyn_cast<FreezeInst>(I)) {
@@ -726,7 +731,6 @@
     if (Preference != WantInteger)
       return false;
     if (ConstantInt *CI = dyn_cast<ConstantInt>(BO->getOperand(1))) {
-      const DataLayout &DL = BO->getModule()->getDataLayout();
       PredValueInfoTy LHSVals;
       computeValueKnownInPredecessorsImpl(BO->getOperand(0), BB, LHSVals,
                                           WantInteger, RecursionSet, CxtI);