There are some cases where icmp(add) can be folded into a new icmp. Handle them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46687 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 19 insertions, 0 deletions

diff --git a/test/Transforms/InstCombine/2008-01-29-AddICmp.ll b/test/Transforms/InstCombine/2008-01-29-AddICmp.ll
new file mode 100644
index 0000000000..43604b8b13
--- /dev/null
+++ b/test/Transforms/InstCombine/2008-01-29-AddICmp.ll
@@ -0,0 +1,19 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep {a.off}
+
+define i1 @test1(i32 %a) {
+  %a.off = add i32 %a, 4          ; <i32> [#uses=1]
+  %C = icmp ult i32 %a.off, 4             ; <i1> [#uses=1]
+  ret i1 %C
+}
+
+define i1 @test2(i32 %a) {
+  %a.off = sub i32 %a, 4          ; <i32> [#uses=1]
+  %C = icmp ugt i32 %a.off, -5             ; <i1> [#uses=1]
+  ret i1 %C
+}
+
+define i1 @test3(i32 %a) {
+  %a.off = add i32 %a, 4          ; <i32> [#uses=1]
+  %C = icmp slt i32 %a.off, 2147483652             ; <i1> [#uses=1]
+  ret i1 %C
+}