fix Transforms/InstCombine/2007-05-10-icmp-or.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36984 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 950404a7f8167b818bfc1ce0e69e1a0eb24d03e7..51c860776c83f771cee9bec930cab411f3744a1b 100644 (file)
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -3919,13 +3919,18 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
             LHSCC != ICmpInst::ICMP_UGE && LHSCC != ICmpInst::ICMP_ULE &&
             RHSCC != ICmpInst::ICMP_UGE && RHSCC != ICmpInst::ICMP_ULE &&
             LHSCC != ICmpInst::ICMP_SGE && LHSCC != ICmpInst::ICMP_SLE &&
-            RHSCC != ICmpInst::ICMP_SGE && RHSCC != ICmpInst::ICMP_SLE) {
+            RHSCC != ICmpInst::ICMP_SGE && RHSCC != ICmpInst::ICMP_SLE &&
+            // We can't fold (ugt x, C) | (sgt x, C2).
+            PredicatesFoldable(LHSCC, RHSCC)) {
           // Ensure that the larger constant is on the RHS.
-          ICmpInst::Predicate GT = ICmpInst::isSignedPredicate(LHSCC) ? 
-            ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
-          Constant *Cmp = ConstantExpr::getICmp(GT, LHSCst, RHSCst);
           ICmpInst *LHS = cast<ICmpInst>(Op0);
-          if (cast<ConstantInt>(Cmp)->getZExtValue()) {
+          bool NeedsSwap;
+          if (ICmpInst::isSignedPredicate(LHSCC))
+            NeedsSwap = LHSCst->getValue().sgt(LHSCst->getValue());
+          else
+            NeedsSwap = LHSCst->getValue().ugt(LHSCst->getValue());
+            
+          if (NeedsSwap) {
             std::swap(LHS, RHS);
             std::swap(LHSCst, RHSCst);
             std::swap(LHSCC, RHSCC);