Revert "[VPlan] Expand WidenInt inductions with nuw/nsw" (#168080)

Reverts llvm/llvm-project#163538

This is causing build failures on the two-stage RVV buildbots. e.g.
https://lab.llvm.org/buildbot/#/builders/214/builds/1363. I've shared a
reproducer and more information at
https://github.com/llvm/llvm-project/pull/163538#issuecomment-3533482822

This reverts commit 355e0f94af5adabe90ac57110ce1b47596afd4cd.

1 files changed, 3 insertions, 12 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 89893af5c114..58fcab40d589 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -7639,10 +7639,6 @@ createWidenInductionRecipes(VPInstruction *PhiR,
   assert(Plan.getLiveIn(IndDesc.getStartValue()) == Start &&
          "Start VPValue must match IndDesc's start value");
 
-  // It is always safe to copy over the NoWrap and FastMath flags. In
-  // particular, when folding tail by masking, the masked-off lanes are never
-  // used, so it is safe.
-  VPIRFlags Flags = vputils::getFlagsFromIndDesc(IndDesc);
   VPValue *Step =
       vputils::getOrCreateVPValueForSCEVExpr(Plan, IndDesc.getStep());
 
@@ -7655,7 +7651,7 @@ createWidenInductionRecipes(VPInstruction *PhiR,
 
   PHINode *Phi = cast<PHINode>(PhiR->getUnderlyingInstr());
   return new VPWidenIntOrFpInductionRecipe(Phi, Start, Step, &Plan.getVF(),
-                                           IndDesc, Flags, PhiR->getDebugLoc());
+                                           IndDesc, PhiR->getDebugLoc());
 }
 
 VPHeaderPHIRecipe *
@@ -7709,15 +7705,10 @@ VPRecipeBuilder::tryToOptimizeInductionTruncate(VPInstruction *VPI,
   PHINode *Phi = WidenIV->getPHINode();
   VPValue *Start = WidenIV->getStartValue();
   const InductionDescriptor &IndDesc = WidenIV->getInductionDescriptor();
-
-  // It is always safe to copy over the NoWrap and FastMath flags. In
-  // particular, when folding tail by masking, the masked-off lanes are never
-  // used, so it is safe.
-  VPIRFlags Flags = vputils::getFlagsFromIndDesc(IndDesc);
   VPValue *Step =
       vputils::getOrCreateVPValueForSCEVExpr(Plan, IndDesc.getStep());
-  return new VPWidenIntOrFpInductionRecipe(
-      Phi, Start, Step, &Plan.getVF(), IndDesc, I, Flags, VPI->getDebugLoc());
+  return new VPWidenIntOrFpInductionRecipe(Phi, Start, Step, &Plan.getVF(),
+                                           IndDesc, I, VPI->getDebugLoc());
 }
 
 VPSingleDefRecipe *VPRecipeBuilder::tryToWidenCall(VPInstruction *VPI,