[llvm] 19732a3 - [SCEV] Check correct binary operator for nowrap flags

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2023-04-27T11:25:40+02:00
New Revision: 19732a3eaa978f2c65c233a97593b09e43a618cc

URL: https://github.com/llvm/llvm-project/commit/19732a3eaa978f2c65c233a97593b09e43a618cc
DIFF: https://github.com/llvm/llvm-project/commit/19732a3eaa978f2c65c233a97593b09e43a618cc.diff

LOG: [SCEV] Check correct binary operator for nowrap flags

We should be checking the current BO here, not the nested one. If
the current BO has nowrap flags (and is UB on poison), then we'll
fetch both operand SCEVs of that BO. We'll check the nested BO
on the next iteration of the do/while loop.

Added: 
    

Modified: 
    llvm/lib/Analysis/ScalarEvolution.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 861dea21f49b..d82ffe52c4cb 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -7452,8 +7452,8 @@ ScalarEvolution::getOperandsToCreate(Value *V, SmallVectorImpl<Value *> &Ops) {
         }
         // CreateSCEV calls getNoWrapFlagsFromUB, which under certain conditions
         // requires a SCEV for the LHS.
-        if (NewBO->Op && (NewBO->IsNSW || NewBO->IsNUW)) {
-          auto *I = dyn_cast<Instruction>(NewBO->Op);
+        if (BO->Op && (BO->IsNSW || BO->IsNUW)) {
+          auto *I = dyn_cast<Instruction>(BO->Op);
           if (I && programUndefinedIfPoison(I)) {
             Ops.push_back(BO->LHS);
             break;