From: Nikita Popov <npopov@redhat.com>
Date: Tue, 4 Oct 2022 09:02:31 +0000 (+0200)
Subject: [ValueTracking] Avoid known bits fallthrough for freeze (NFCI)
X-Git-Tag: upstream/17.0.6~31685
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=45dec8f5fdd82cf1ed456b0fa860774a26c0acca;p=platform%2Fupstream%2Fllvm.git

[ValueTracking] Avoid known bits fallthrough for freeze (NFCI)

The known bits logic should never produce a better result than
the direct recursive non-zero query here, so skip the fallthrough.
---

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index e7c7d63..81f606f 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -2737,10 +2737,9 @@ bool isKnownNonZero(const Value *V, const APInt &DemandedElts, unsigned Depth,
     }
     break;
   case Instruction::Freeze:
-    if (isKnownNonZero(I->getOperand(0), Depth, Q) &&
-        isGuaranteedNotToBePoison(I->getOperand(0), Q.AC, Q.CxtI, Q.DT, Depth))
-      return true;
-    break;
+    return isKnownNonZero(I->getOperand(0), Depth, Q) &&
+           isGuaranteedNotToBePoison(I->getOperand(0), Q.AC, Q.CxtI, Q.DT,
+                                     Depth);
   case Instruction::Call:
     if (cast<CallInst>(I)->getIntrinsicID() == Intrinsic::vscale)
       return true;