Thread comparisons over udiv/sdiv/ashr/lshr exact and lshr nuw/nsw whenever
possible. This goes into instcombine and instsimplify because instsimplify
doesn't need to check hasOneUse since it returns (almost exclusively) constants.
This fixes PR9343 #4 #5 and #8!
llvm-svn: 127064
diff --git a/llvm/test/Transforms/InstSimplify/compare.ll b/llvm/test/Transforms/InstSimplify/compare.ll
index 7b92de1..7174e7f 100644
--- a/llvm/test/Transforms/InstSimplify/compare.ll
+++ b/llvm/test/Transforms/InstSimplify/compare.ll
@@ -261,6 +261,15 @@
; CHECK: ret i1 true
}
+define i1 @udiv2(i32 %X, i32 %Y, i32 %Z) {
+; CHECK: @udiv2
+ %A = udiv exact i32 10, %Z
+ %B = udiv exact i32 20, %Z
+ %C = icmp ult i32 %A, %B
+ ret i1 %C
+; CHECK: ret i1 true
+}
+
define i1 @sdiv1(i32 %X) {
; CHECK: @sdiv1
%A = sdiv i32 %X, 1000000