[GuardWidening] Use getEquivalentICmp to fold constant compares

`ConstantRange::getEquivalentICmp` is more general, and better
factored.

llvm-svn: 270019

1 files changed, 45 insertions, 1 deletions

diff --git a/llvm/test/Transforms/GuardWidening/basic.ll b/llvm/test/Transforms/GuardWidening/basic.ll
index cb49eebcbab..5b746a5d7dd 100644
--- a/llvm/test/Transforms/GuardWidening/basic.ll
+++ b/llvm/test/Transforms/GuardWidening/basic.ll
@@ -126,7 +126,7 @@ leave:
 define void @f_5(i32 %a) {
 ; CHECK-LABEL: @f_5(
 entry:
-; CHECK:  %wide.chk = icmp ugt i32 %a, 10
+; CHECK:  %wide.chk = icmp uge i32 %a, 11
 ; CHECK:  call void (i1, ...) @llvm.experimental.guard(i1 %wide.chk) [ "deopt"() ]
 ; CHECK:  br i1 undef, label %left, label %right
 
@@ -335,3 +335,47 @@ entry:
   call void(i1, ...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
   ret void
 }
+
+define void @f_13(i32 %a) {
+; CHECK-LABEL: @f_13(
+entry:
+; CHECK:  %wide.chk = icmp ult i32 %a, 10
+; CHECK:  call void (i1, ...) @llvm.experimental.guard(i1 %wide.chk) [ "deopt"() ]
+; CHECK:  br i1 undef, label %left, label %right
+
+  %cond_0 = icmp ult i32 %a, 14
+  call void(i1, ...) @llvm.experimental.guard(i1 %cond_0) [ "deopt"() ]
+  br i1 undef, label %left, label %right
+
+left:
+  %cond_1 = icmp slt i32 %a, 10
+  call void(i1, ...) @llvm.experimental.guard(i1 %cond_1) [ "deopt"() ]
+  ret void
+
+right:
+  ret void
+}
+
+define void @f_14(i32 %a) {
+; CHECK-LABEL: @f_14(
+entry:
+; CHECK:  %cond_0 = icmp ult i32 %a, 14
+; CHECK:  call void (i1, ...) @llvm.experimental.guard(i1 %cond_0) [ "deopt"() ]
+; CHECK:  br i1 undef, label %left, label %right
+
+  %cond_0 = icmp ult i32 %a, 14
+  call void(i1, ...) @llvm.experimental.guard(i1 %cond_0) [ "deopt"() ]
+  br i1 undef, label %left, label %right
+
+left:
+; CHECK: left:
+; CHECK:  %cond_1 = icmp sgt i32 %a, 10
+; CHECK:  call void (i1, ...) @llvm.experimental.guard(i1 %cond_1) [ "deopt"() ]
+
+  %cond_1 = icmp sgt i32 %a, 10
+  call void(i1, ...) @llvm.experimental.guard(i1 %cond_1) [ "deopt"() ]
+  ret void
+
+right:
+  ret void
+}