From: Chris Lattner <sabre@nondot.org>
Date: Thu, 22 Nov 2007 23:47:13 +0000 (+0000)
Subject: Fix PR1817.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=eec8b9a7d6630d45985e72f5fa396b48ba490d68;p=oota-llvm.git

Fix PR1817.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44284 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index e8cd86778ae..c8df4128643 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -3463,7 +3463,12 @@ Instruction *InstCombiner::visitAnd(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 &&
+            
+            // Don't try to fold ICMP_SLT + ICMP_ULT.
+            (ICmpInst::isEquality(LHSCC) || ICmpInst::isEquality(RHSCC) ||
+             ICmpInst::isSignedPredicate(LHSCC) == 
+                 ICmpInst::isSignedPredicate(RHSCC))) {
           // Ensure that the larger constant is on the RHS.
           ICmpInst::Predicate GT = ICmpInst::isSignedPredicate(LHSCC) ? 
             ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
diff --git a/test/Transforms/InstCombine/2007-11-22-IcmpCrash.ll b/test/Transforms/InstCombine/2007-11-22-IcmpCrash.ll
new file mode 100644
index 00000000000..1f211b65d3f
--- /dev/null
+++ b/test/Transforms/InstCombine/2007-11-22-IcmpCrash.ll
@@ -0,0 +1,16 @@
+; RUN: llvm-as < %s | opt -instcombine -disable-output
+; PR1817
+
+define i1 @test1(i32 %X) {
+	%A = icmp slt i32 %X, 10
+	%B = icmp ult i32 %X, 10
+	%C = and i1 %A, %B
+	ret i1 %C
+}
+
+define i1 @test2(i32 %X) {
+	%A = icmp slt i32 %X, 10
+	%B = icmp ult i32 %X, 10
+	%C = or i1 %A, %B
+	ret i1 %C
+}