Recognize and simplify

(A+B) == A  ->  B == 0
A == (A+B)  ->  B == 0



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124567 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 16 insertions, 0 deletions

diff --git a/test/Transforms/InstCombine/add.ll b/test/Transforms/InstCombine/add.ll
index 4719809d6d..b3a7f52607 100644
--- a/test/Transforms/InstCombine/add.ll
+++ b/test/Transforms/InstCombine/add.ll
@@ -275,3 +275,19 @@ define i32 @test36(i32 %a) {
 	%q = and i32 %z, 1  ; always zero
 	ret i32 %q
 }
+
+define i32 @test37(i32 %a, i32 %b) nounwind readnone {
+entry:
+  %add = add nsw i32 %a, %b
+  %cmp = icmp eq i32 %add, %a
+  %conv = zext i1 %cmp to i32
+  ret i32 %conv
+}
+
+define i32 @test38(i32 %a, i32 %b) nounwind readnone {
+entry:
+  %add = add nsw i32 %a, %b
+  %cmp = icmp eq i32 %add, %a
+  %conv = zext i1 %cmp to i32
+  ret i32 %conv
+}