[InstCombine] add tests for fabs(x) / fabs (x); NFC

diff --git a/llvm/test/Transforms/InstCombine/fdiv.ll b/llvm/test/Transforms/InstCombine/fdiv.ll
index 888f5e8..c5ea741 100644 (file)
--- a/llvm/test/Transforms/InstCombine/fdiv.ll
+++ b/llvm/test/Transforms/InstCombine/fdiv.ll
@@ -1,6 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -S -instcombine < %s | FileCheck %s
 
+declare float @llvm.fabs.f32(float) nounwind readnone
+
 define float @exact_inverse(float %x) {
 ; CHECK-LABEL: @exact_inverse(
 ; CHECK-NEXT:    [[DIV:%.*]] = fmul float [[X:%.*]], 1.250000e-01
@@ -570,3 +572,27 @@ define float @fdiv_fneg1_extra_use(float %x, float %y) {
   %div = fdiv float %neg, %y
   ret float %div
 }
+
+define float @fabs_same_op(float %x) {
+; CHECK-LABEL: @fabs_same_op(
+; CHECK-NEXT:    [[A:%.*]] = call float @llvm.fabs.f32(float [[X:%.*]])
+; CHECK-NEXT:    [[R:%.*]] = fdiv float [[A]], [[A]]
+; CHECK-NEXT:    ret float [[R]]
+;
+  %a = call float @llvm.fabs.f32(float %x)
+  %r = fdiv float %a, %a
+  ret float %r
+}
+
+define float @fabs_same_op_extra_use(float %x) {
+; CHECK-LABEL: @fabs_same_op_extra_use(
+; CHECK-NEXT:    [[A:%.*]] = call float @llvm.fabs.f32(float [[X:%.*]])
+; CHECK-NEXT:    call void @use_f32(float [[A]])
+; CHECK-NEXT:    [[R:%.*]] = fdiv reassoc ninf float [[A]], [[A]]
+; CHECK-NEXT:    ret float [[R]]
+;
+  %a = call float @llvm.fabs.f32(float %x)
+  call void @use_f32(float %a)
+  %r = fdiv ninf reassoc float %a, %a
+  ret float %r
+}