commit abe2cc17dac0eacc47f2bbc4a41fa1ccc7ad8fe1
author Nick Lewycky <nicholas@mxc.ca> Mon Apr 13 19:17:37 2015 +0000
committer Nick Lewycky <nicholas@mxc.ca> Mon Apr 13 19:17:37 2015 +0000
tree fab87b3109ec0f1f662b1af604af96401e786902
parent 2114275263405e842f34a313297889c5064535f5

Subtraction is not commutative. Fixes PR23212!

llvm-svn: 234780

llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 8c6dc09..11094e9 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -416,12 +416,10 @@
     }
     break;
 
-    case Intrinsic::uadd_with_overflow: // FALLTHROUGH
-    case Intrinsic::sadd_with_overflow: // FALLTHROUGH
-    case Intrinsic::usub_with_overflow: // FALLTHROUGH
-    case Intrinsic::ssub_with_overflow: // FALLTHROUGH
-    case Intrinsic::umul_with_overflow: // FALLTHROUGH
-    case Intrinsic::smul_with_overflow: {
+  case Intrinsic::uadd_with_overflow:
+  case Intrinsic::sadd_with_overflow:
+  case Intrinsic::umul_with_overflow:
+  case Intrinsic::smul_with_overflow:
     if (isa<Constant>(II->getArgOperand(0)) &&
         !isa<Constant>(II->getArgOperand(1))) {
       // Canonicalize constants into the RHS.
@@ -430,7 +428,10 @@
       II->setArgOperand(1, LHS);
       return II;
     }
+    [[clang::fallthrough]];
 
+  case Intrinsic::usub_with_overflow:
+  case Intrinsic::ssub_with_overflow: {
     OverflowCheckFlavor OCF =
         IntrinsicIDToOverflowCheckFlavor(II->getIntrinsicID());
     assert(OCF != OCF_INVALID && "unexpected!");