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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17043 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/ADCE.cpp b/lib/Transforms/Scalar/ADCE.cpp
index 7fafe26d4a9affc74ac7d4ed41c212db362a61c6..e1f228d6fab70e799c827b31d8b66a25d014f767 100644 (file)
--- a/lib/Transforms/Scalar/ADCE.cpp
+++ b/lib/Transforms/Scalar/ADCE.cpp
@@ -234,6 +234,7 @@ bool ADCE::doADCE() {
         }
       } else if (I->mayWriteToMemory() || isa<ReturnInst>(I) ||
                  isa<UnwindInst>(I)) {
+        // Unreachable instructions are not marked intrinsically live here.
        markInstructionLive(I);
       } else if (isInstructionTriviallyDead(I)) {
         // Remove the instruction from it's basic block...