Teach instsimplify that X+Y>=X+Z is the same as Y>=Z if neither side overflows,

plus some variations of this.  According to my auto-simplifier this occurs a lot
but usually in combination with max/min idioms.  Because max/min aren't handled
yet this unfortunately doesn't have much effect in the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125462 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 0 deletions

diff --git a/test/Transforms/InstSimplify/2011-01-18-Compare.ll b/test/Transforms/InstSimplify/compare.ll
index e08ee2c6fb..250e44ce34 100644
--- a/test/Transforms/InstSimplify/2011-01-18-Compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -91,6 +91,26 @@ define i1 @add3(i8 %x, i8 %y) {
 ; CHECK: ret i1 %c
 }
 
+define i1 @add4(i32 %x, i32 %y) {
+; CHECK: @add4
+  %z = add nsw i32 %y, 1
+  %s1 = add nsw i32 %x, %y
+  %s2 = add nsw i32 %x, %z
+  %c = icmp slt i32 %s1, %s2
+  ret i1 %c
+; CHECK: ret i1 true
+}
+
+define i1 @add5(i32 %x, i32 %y) {
+; CHECK: @add5
+  %z = add nuw i32 %y, 1
+  %s1 = add nuw i32 %x, %z
+  %s2 = add nuw i32 %x, %y
+  %c = icmp ugt i32 %s1, %s2
+  ret i1 %c
+; CHECK: ret i1 true
+}
+
 define i1 @addpowtwo(i32 %x, i32 %y) {
 ; CHECK: @addpowtwo
   %l = lshr i32 %x, 1