[llvm] [InstCombine] Support minimumnum/maximumnum (PR #180529)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,379 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s
+
+define float @maximumnum_f32_1_maximumnum_val_p0(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_val_p0(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call float @llvm.maximumnum.f32(float %x, float 0.0)
+  %z = call float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_1_maximumnum_p0_val_fast(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_p0_val_fast(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call float @llvm.maximumnum.f32(float 0.0, float %x)
+  %z = call fast float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_1_maximumnum_p0_val_fmf1(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_p0_val_fmf1(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call nnan float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call nnan float @llvm.maximumnum.f32(float 0.0, float %x)
+  %z = call nnan ninf float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_1_maximumnum_p0_val_fmf2(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_p0_val_fmf2(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call ninf float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call nnan ninf float @llvm.maximumnum.f32(float 0.0, float %x)
+  %z = call ninf float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_1_maximumnum_p0_val_fmf3(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_p0_val_fmf3(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call nnan ninf float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call ninf nnan float @llvm.maximumnum.f32(float 0.0, float %x)
+  %z = call ninf nnan float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_p0_maximumnum_val_n0(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_p0_maximumnum_val_n0(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call float @llvm.maximumnum.f32(float [[X]], float 0.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call float @llvm.maximumnum.f32(float %x, float -0.0)
+  %z = call float @llvm.maximumnum.f32(float %y, float 0.0)
+  ret float %z
+}
+
+define float @maximumnum_f32_1_maximumnum_p0_val(float %x) {
+; CHECK-LABEL: define float @maximumnum_f32_1_maximumnum_p0_val(
+; CHECK-SAME: float [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call float @llvm.maximumnum.f32(float [[X]], float 1.000000e+00)
+; CHECK-NEXT:    ret float [[Z]]
+;
+  %y = call float @llvm.maximumnum.f32(float 0.0, float %x)
+  %z = call float @llvm.maximumnum.f32(float %y, float 1.0)
+  ret float %z
+}
+
+define <2 x float> @maximumnum_f32_1_maximumnum_val_p0_val_v2f32(<2 x float> %x) {
+; CHECK-LABEL: define <2 x float> @maximumnum_f32_1_maximumnum_val_p0_val_v2f32(
+; CHECK-SAME: <2 x float> [[X:%.*]]) {
+; CHECK-NEXT:    [[Z:%.*]] = call <2 x float> @llvm.maximumnum.v2f32(<2 x float> [[X]], <2 x float> splat (float 1.000000e+00))
+; CHECK-NEXT:    ret <2 x float> [[Z]]
+;
+  %y = call <2 x float> @llvm.maximumnum.v2f32(<2 x float> %x, <2 x float> zeroinitializer)
+  %z = call <2 x float> @llvm.maximumnum.v2f32(<2 x float> %y, <2 x float><float 1.0, float 1.0>)
+  ret <2 x float> %z
+}
+
+define float @maximumnum4(float %x, float %y, float %z, float %w) {
+; CHECK-LABEL: define float @maximumnum4(
+; CHECK-SAME: float [[X:%.*]], float [[Y:%.*]], float [[Z:%.*]], float [[W:%.*]]) {
+; CHECK-NEXT:    [[A:%.*]] = call float @llvm.maximumnum.f32(float [[X]], float [[Y]])
+; CHECK-NEXT:    [[B:%.*]] = call float @llvm.maximumnum.f32(float [[Z]], float [[W]])
+; CHECK-NEXT:    [[C:%.*]] = call float @llvm.maximumnum.f32(float [[A]], float [[B]])
+; CHECK-NEXT:    ret float [[C]]
+;
+  %a = call float @llvm.maximumnum.f32(float %x, float %y)
+  %b = call float @llvm.maximumnum.f32(float %z, float %w)
+  %c = call float @llvm.maximumnum.f32(float %a, float %b)
+  ret float %c
+}
+
+; PR37404 - https://bugs.llvm.org/show_bug.cgi?id=37404
+
+define <2 x float> @maximumnum_neg_neg(<2 x float> %x, <2 x float> %y) {
+; CHECK-LABEL: define <2 x float> @maximumnum_neg_neg(
+; CHECK-SAME: <2 x float> [[X:%.*]], <2 x float> [[Y:%.*]]) {
+; CHECK-NEXT:    [[TMP1:%.*]] = call <2 x float> @llvm.minimumnum.v2f32(<2 x float> [[X]], <2 x float> [[Y]])
+; CHECK-NEXT:    [[R:%.*]] = fneg <2 x float> [[TMP1]]
+; CHECK-NEXT:    ret <2 x float> [[R]]
+;
+  %negx = fsub <2 x float> <float -0.0, float -0.0>, %x
+  %negy = fsub <2 x float> <float -0.0, float -0.0>, %y
----------------
arsenm wrote:

```suggestion
  %negy = fsub <2 x float> splat(float -0.0), %y
```

https://github.com/llvm/llvm-project/pull/180529