[llvm] 71c5e7b - [msan] Do not deppend on arguments evaluation order

[Vitaly Buka via llvm-commits]

Author: Vitaly Buka
Date: 2022-09-10T13:50:32-07:00
New Revision: 71c5e7b26abaf85d85294170785335dee1ab8afa

URL: https://github.com/llvm/llvm-project/commit/71c5e7b26abaf85d85294170785335dee1ab8afa
DIFF: https://github.com/llvm/llvm-project/commit/71c5e7b26abaf85d85294170785335dee1ab8afa.diff

LOG: [msan] Do not deppend on arguments evaluation order

Clang and GCC do this differently making IR inconsistent.
https://lab.llvm.org/buildbot#builders/6/builds/13120

Added: 
    

Modified: 
    llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index bdb410b48ace..62367dc9bc1c 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -3313,9 +3313,11 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
           Acc = IRB.CreateOr(Acc, More);
         }
 
-        Value *Origin = IRB.CreateSelect(
-            IRB.CreateICmpNE(Acc, Constant::getNullValue(Acc->getType())),
-            getOrigin(PassThru), IRB.CreateLoad(MS.OriginTy, OriginPtr));
+        Value *NotNull =
+            IRB.CreateICmpNE(Acc, Constant::getNullValue(Acc->getType()));
+        Value *PtrOrigin = IRB.CreateLoad(MS.OriginTy, OriginPtr);
+        Value *Origin =
+            IRB.CreateSelect(NotNull, getOrigin(PassThru), PtrOrigin);
 
         setOrigin(&I, Origin);
       } else {