1 files changed, 100 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/fabs.ll b/test/Transforms/InstCombine/fabs.ll
new file mode 100644
index 000000000000..0479549bea3f
--- /dev/null
+++ b/test/Transforms/InstCombine/fabs.ll
@@ -0,0 +1,100 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; Make sure all library calls are eliminated when the input is known positive.
+
+declare float @fabsf(float)
+declare double @fabs(double)
+declare fp128 @fabsl(fp128)
+
+define float @square_fabs_call_f32(float %x) {
+  %mul = fmul float %x, %x
+  %fabsf = tail call float @fabsf(float %mul)
+  ret float %fabsf
+
+; CHECK-LABEL: square_fabs_call_f32(
+; CHECK-NEXT: %mul = fmul float %x, %x
+; CHECK-NEXT: ret float %mul
+}
+
+define double @square_fabs_call_f64(double %x) {
+  %mul = fmul double %x, %x
+  %fabs = tail call double @fabs(double %mul)
+  ret double %fabs
+
+; CHECK-LABEL: square_fabs_call_f64(
+; CHECK-NEXT: %mul = fmul double %x, %x
+; CHECK-NEXT: ret double %mul
+}
+
+define fp128 @square_fabs_call_f128(fp128 %x) {
+  %mul = fmul fp128 %x, %x
+  %fabsl = tail call fp128 @fabsl(fp128 %mul)
+  ret fp128 %fabsl
+
+; CHECK-LABEL: square_fabs_call_f128(
+; CHECK-NEXT: %mul = fmul fp128 %x, %x
+; CHECK-NEXT: ret fp128 %mul
+}
+
+; Make sure all intrinsic calls are eliminated when the input is known positive.
+
+declare float @llvm.fabs.f32(float)
+declare double @llvm.fabs.f64(double)
+declare fp128 @llvm.fabs.f128(fp128)
+
+define float @square_fabs_intrinsic_f32(float %x) {
+  %mul = fmul float %x, %x
+  %fabsf = tail call float @llvm.fabs.f32(float %mul)
+  ret float %fabsf
+
+; CHECK-LABEL: square_fabs_intrinsic_f32(
+; CHECK-NEXT: %mul = fmul float %x, %x
+; CHECK-NEXT: ret float %mul
+}
+
+define double @square_fabs_intrinsic_f64(double %x) {
+  %mul = fmul double %x, %x
+  %fabs = tail call double @llvm.fabs.f64(double %mul)
+  ret double %fabs
+
+; CHECK-LABEL: square_fabs_intrinsic_f64(
+; CHECK-NEXT: %mul = fmul double %x, %x
+; CHECK-NEXT: ret double %mul
+}
+
+define fp128 @square_fabs_intrinsic_f128(fp128 %x) {
+  %mul = fmul fp128 %x, %x
+  %fabsl = tail call fp128 @llvm.fabs.f128(fp128 %mul)
+  ret fp128 %fabsl
+
+; CHECK-LABEL: square_fabs_intrinsic_f128(
+; CHECK-NEXT: %mul = fmul fp128 %x, %x
+; CHECK-NEXT: ret fp128 %mul
+}
+
+; Shrinking a library call to a smaller type should not be inhibited by nor inhibit the square optimization.
+
+define float @square_fabs_shrink_call1(float %x) {
+  %ext = fpext float %x to double
+  %sq = fmul double %ext, %ext
+  %fabs = call double @fabs(double %sq)
+  %trunc = fptrunc double %fabs to float
+  ret float %trunc
+
+; CHECK-LABEL: square_fabs_shrink_call1(
+; CHECK-NEXT: %trunc = fmul float %x, %x
+; CHECK-NEXT: ret float %trunc
+}
+
+define float @square_fabs_shrink_call2(float %x) {
+  %sq = fmul float %x, %x
+  %ext = fpext float %sq to double
+  %fabs = call double @fabs(double %ext)
+  %trunc = fptrunc double %fabs to float
+  ret float %trunc
+
+; CHECK-LABEL: square_fabs_shrink_call2(
+; CHECK-NEXT: %sq = fmul float %x, %x
+; CHECK-NEXT: ret float %sq
+}
+