AArch64/PowerPC/SystemZ/X86: This patch fixes the interface, usage, and all

in-tree implementations of TargetLoweringBase::isFMAFasterThanMulAndAdd in
order to resolve the following issues with fmuladd (i.e. optional FMA)
intrinsics:

1. On X86(-64) targets, ISD::FMA nodes are formed when lowering fmuladd
intrinsics even if the subtarget does not support FMA instructions, leading
to laughably bad code generation in some situations.

2. On AArch64 targets, ISD::FMA nodes are formed for operations on fp128,
resulting in a call to a software fp128 FMA implementation.

3. On PowerPC targets, FMAs are not generated from fmuladd intrinsics on types
like v2f32, v8f32, v4f64, etc., even though they promote, split, scalarize,
etc. to types that support hardware FMAs.

The function has also been slightly renamed for consistency and to force a
merge/build conflict for any out-of-tree target implementing it. To resolve,
see comments and fixed in-tree examples.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185956 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 233 insertions, 3 deletions

diff --git a/test/CodeGen/AArch64/fp-dp3.ll b/test/CodeGen/AArch64/fp-dp3.ll
index 39db9be..f372c43 100644
--- a/test/CodeGen/AArch64/fp-dp3.ll
+++ b/test/CodeGen/AArch64/fp-dp3.ll
@@ -1,102 +1,136 @@
 ; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu -fp-contract=fast | FileCheck %s
+; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu | FileCheck %s -check-prefix=CHECK-NOFAST
 
 declare float @llvm.fma.f32(float, float, float)
 declare double @llvm.fma.f64(double, double, double)
 
 define float @test_fmadd(float %a, float %b, float %c) {
 ; CHECK: test_fmadd:
+; CHECK-NOFAST: test_fmadd:
   %val = call float @llvm.fma.f32(float %a, float %b, float %c)
 ; CHECK: fmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %val
 }
 
 define float @test_fmsub(float %a, float %b, float %c) {
 ; CHECK: test_fmsub:
+; CHECK-NOFAST: test_fmsub:
   %nega = fsub float -0.0, %a
   %val = call float @llvm.fma.f32(float %nega, float %b, float %c)
 ; CHECK: fmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %val
 }
 
 define float @test_fnmadd(float %a, float %b, float %c) {
 ; CHECK: test_fnmadd:
+; CHECK-NOFAST: test_fnmadd:
   %negc = fsub float -0.0, %c
   %val = call float @llvm.fma.f32(float %a, float %b, float %negc)
 ; CHECK: fnmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fnmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %val
 }
 
 define float @test_fnmsub(float %a, float %b, float %c) {
 ; CHECK: test_fnmsub:
+; CHECK-NOFAST: test_fnmsub:
   %nega = fsub float -0.0, %a
   %negc = fsub float -0.0, %c
   %val = call float @llvm.fma.f32(float %nega, float %b, float %negc)
 ; CHECK: fnmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fnmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %val
 }
 
 define double @testd_fmadd(double %a, double %b, double %c) {
 ; CHECK: testd_fmadd:
+; CHECK-NOFAST: testd_fmadd:
   %val = call double @llvm.fma.f64(double %a, double %b, double %c)
 ; CHECK: fmadd {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
+; CHECK-NOFAST: fmadd {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
   ret double %val
 }
 
 define double @testd_fmsub(double %a, double %b, double %c) {
 ; CHECK: testd_fmsub:
+; CHECK-NOFAST: testd_fmsub:
   %nega = fsub double -0.0, %a
   %val = call double @llvm.fma.f64(double %nega, double %b, double %c)
 ; CHECK: fmsub {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
+; CHECK-NOFAST: fmsub {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
   ret double %val
 }
 
 define double @testd_fnmadd(double %a, double %b, double %c) {
 ; CHECK: testd_fnmadd:
+; CHECK-NOFAST: testd_fnmadd:
   %negc = fsub double -0.0, %c
   %val = call double @llvm.fma.f64(double %a, double %b, double %negc)
 ; CHECK: fnmadd {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
+; CHECK-NOFAST: fnmadd {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
   ret double %val
 }
 
 define double @testd_fnmsub(double %a, double %b, double %c) {
 ; CHECK: testd_fnmsub:
+; CHECK-NOFAST: testd_fnmsub:
   %nega = fsub double -0.0, %a
   %negc = fsub double -0.0, %c
   %val = call double @llvm.fma.f64(double %nega, double %b, double %negc)
 ; CHECK: fnmsub {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
+; CHECK-NOFAST: fnmsub {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}
   ret double %val
 }
 
 define float @test_fmadd_unfused(float %a, float %b, float %c) {
 ; CHECK: test_fmadd_unfused:
+; CHECK-NOFAST: test_fmadd_unfused:
   %prod = fmul float %b, %c
   %sum = fadd float %a, %prod
 ; CHECK: fmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST-NOT: fmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %sum
 }
 
 define float @test_fmsub_unfused(float %a, float %b, float %c) {
 ; CHECK: test_fmsub_unfused:
+; CHECK-NOFAST: test_fmsub_unfused:
   %prod = fmul float %b, %c
   %diff = fsub float %a, %prod
 ; CHECK: fmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST-NOT: fmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %diff
 }
 
 define float @test_fnmadd_unfused(float %a, float %b, float %c) {
 ; CHECK: test_fnmadd_unfused:
+; CHECK-NOFAST: test_fnmadd_unfused:
   %nega = fsub float -0.0, %a
   %prod = fmul float %b, %c
   %sum = fadd float %nega, %prod
 ; CHECK: fnmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST-NOT: fnmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %sum
 }
 
 define float @test_fnmsub_unfused(float %a, float %b, float %c) {
 ; CHECK: test_fnmsub_unfused:
+; CHECK-NOFAST: test_fnmsub_unfused:
   %nega = fsub float -0.0, %a
   %prod = fmul float %b, %c
   %diff = fsub float %nega, %prod
 ; CHECK: fnmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST-NOT: fnmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fneg {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK-NOFAST: fsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
   ret float %diff
 }
diff --git a/test/CodeGen/AArch64/illegal-float-ops.ll b/test/CodeGen/AArch64/illegal-float-ops.ll
index 446151b..a398f7b 100644
--- a/test/CodeGen/AArch64/illegal-float-ops.ll
+++ b/test/CodeGen/AArch64/illegal-float-ops.ll
@@ -219,3 +219,29 @@ define void @test_frem(float %float, double %double, fp128 %fp128) {
 
   ret void
 }
+
+declare fp128 @llvm.fma.f128(fp128, fp128, fp128)
+
+define void @test_fma(fp128 %fp128) {
+; CHECK: test_fma:
+
+  %fmafp128 = call fp128 @llvm.fma.f128(fp128 %fp128, fp128 %fp128, fp128 %fp128)
+  store fp128 %fmafp128, fp128* @varfp128
+; CHECK: bl fmal
+
+  ret void
+}
+
+declare fp128 @llvm.fmuladd.f128(fp128, fp128, fp128)
+
+define void @test_fmuladd(fp128 %fp128) {
+; CHECK: test_fmuladd:
+
+  %fmuladdfp128 = call fp128 @llvm.fmuladd.f128(fp128 %fp128, fp128 %fp128, fp128 %fp128)
+  store fp128 %fmuladdfp128, fp128* @varfp128
+; CHECK-NOT: bl fmal
+; CHECK: bl __multf3
+; CHECK: bl __addtf3
+
+  ret void
+}
diff --git a/test/CodeGen/PowerPC/vec_fmuladd.ll b/test/CodeGen/PowerPC/vec_fmuladd.ll
new file mode 100644
index 0000000..b1bc377
--- /dev/null
+++ b/test/CodeGen/PowerPC/vec_fmuladd.ll
@@ -0,0 +1,56 @@
+; RUN: llc -mcpu=pwr6 -mattr=+altivec < %s | FileCheck %s
+
+target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v128:128:128-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+declare <2 x float> @llvm.fmuladd.v2f32(<2 x float> %val, <2 x float>, <2 x float>)
+declare <4 x float> @llvm.fmuladd.v4f32(<4 x float> %val, <4 x float>, <4 x float>)
+declare <8 x float> @llvm.fmuladd.v8f32(<8 x float> %val, <8 x float>, <8 x float>)
+declare <2 x double> @llvm.fmuladd.v2f64(<2 x double> %val, <2 x double>, <2 x double>)
+declare <4 x double> @llvm.fmuladd.v4f64(<4 x double> %val, <4 x double>, <4 x double>)
+
+define <2 x float> @v2f32_fmuladd(<2 x float> %x) nounwind readnone {
+entry:
+  %fmuladd = call <2 x float> @llvm.fmuladd.v2f32 (<2 x float> %x, <2 x float> %x, <2 x float> %x)
+  ret <2 x float> %fmuladd
+}
+; fmuladd (<2 x float>) is promoted to fmuladd (<4 x float>)
+; CHECK: v2f32_fmuladd:
+; CHECK: vmaddfp {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+
+define <4 x float> @v4f32_fmuladd(<4 x float> %x) nounwind readnone {
+entry:
+  %fmuladd = call <4 x float> @llvm.fmuladd.v4f32 (<4 x float> %x, <4 x float> %x, <4 x float> %x)
+  ret <4 x float> %fmuladd
+}
+; CHECK: v4f32_fmuladd:
+; CHECK: vmaddfp {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+
+define <8 x float> @v8f32_fmuladd(<8 x float> %x) nounwind readnone {
+entry:
+  %fmuladd = call <8 x float> @llvm.fmuladd.v8f32 (<8 x float> %x, <8 x float> %x, <8 x float> %x)
+  ret <8 x float> %fmuladd
+}
+; CHECK: v8f32_fmuladd:
+; CHECK: vmaddfp {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+; CHECK: vmaddfp {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+
+define <2 x double> @v2f64_fmuladd(<2 x double> %x) nounwind readnone {
+entry:
+  %fmuladd = call <2 x double> @llvm.fmuladd.v2f64 (<2 x double> %x, <2 x double> %x, <2 x double> %x)
+  ret <2 x double> %fmuladd
+}
+; CHECK: v2f64_fmuladd:
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}
+
+define <4 x double> @v4f64_fmuladd(<4 x double> %x) nounwind readnone {
+entry:
+  %fmuladd = call <4 x double> @llvm.fmuladd.v4f64 (<4 x double> %x, <4 x double> %x, <4 x double> %x)
+  ret <4 x double> %fmuladd
+}
+; CHECK: v4f64_fmuladd:
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}} 
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}} 
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}} 
+; CHECK: fmadd {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}} 
diff --git a/test/CodeGen/X86/extended-fma-contraction.ll b/test/CodeGen/X86/extended-fma-contraction.ll
new file mode 100644
index 0000000..ef2c22b
--- /dev/null
+++ b/test/CodeGen/X86/extended-fma-contraction.ll
@@ -0,0 +1,22 @@
+; RUN: llc -march=x86 -mattr=+fma4 -mtriple=x86_64-apple-darwin < %s | FileCheck %s
+; RUN: llc -march=x86 -mtriple=x86_64-apple-darwin < %s | FileCheck %s --check-prefix=CHECK-NOFMA
+
+; CHECK: fmafunc
+define <3 x float> @fmafunc(<3 x float> %a, <3 x float> %b, <3 x float> %c) {
+
+; CHECK-NOT: vmulps
+; CHECK-NOT: vaddps
+; CHECK: vfmaddps
+; CHECK-NOT: vmulps
+; CHECK-NOT: vaddps
+
+; CHECK-NOFMA-NOT: calll
+; CHECK-NOFMA: vmulps
+; CHECK-NOFMA: vaddps
+; CHECK-NOFMA-NOT: calll
+
+  %ret = tail call <3 x float> @llvm.fmuladd.v3f32(<3 x float> %a, <3 x float> %b, <3 x float> %c)
+  ret <3 x float> %ret
+}
+
+declare <3 x float> @llvm.fmuladd.v3f32(<3 x float>, <3 x float>, <3 x float>) nounwind readnone
diff --git a/test/CodeGen/X86/fma_patterns_wide.ll b/test/CodeGen/X86/fma_patterns_wide.ll
new file mode 100644
index 0000000..d84e5a0
--- /dev/null
+++ b/test/CodeGen/X86/fma_patterns_wide.ll
@@ -0,0 +1,84 @@
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=core-avx2 -mattr=avx2,+fma -fp-contract=fast | FileCheck %s
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=bdver2 -mattr=-fma4 -fp-contract=fast | FileCheck %s
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=bdver1 -fp-contract=fast | FileCheck %s --check-prefix=CHECK_FMA4
+
+; CHECK: test_x86_fmadd_ps_y_wide
+; CHECK: vfmadd213ps
+; CHECK: vfmadd213ps
+; CHECK: ret
+; CHECK_FMA4: test_x86_fmadd_ps_y_wide
+; CHECK_FMA4: vfmaddps
+; CHECK_FMA4: vfmaddps
+; CHECK_FMA4: ret
+define <16 x float> @test_x86_fmadd_ps_y_wide(<16 x float> %a0, <16 x float> %a1, <16 x float> %a2) {
+  %x = fmul <16 x float> %a0, %a1
+  %res = fadd <16 x float> %x, %a2
+  ret <16 x float> %res
+}
+
+; CHECK: test_x86_fmsub_ps_y_wide
+; CHECK: vfmsub213ps
+; CHECK: vfmsub213ps
+; CHECK: ret
+; CHECK_FMA4: test_x86_fmsub_ps_y_wide
+; CHECK_FMA4: vfmsubps
+; CHECK_FMA4: vfmsubps
+; CHECK_FMA4: ret
+define <16 x float> @test_x86_fmsub_ps_y_wide(<16 x float> %a0, <16 x float> %a1, <16 x float> %a2) {
+  %x = fmul <16 x float> %a0, %a1
+  %res = fsub <16 x float> %x, %a2
+  ret <16 x float> %res
+}
+
+; CHECK: test_x86_fnmadd_ps_y_wide
+; CHECK: vfnmadd213ps
+; CHECK: vfnmadd213ps
+; CHECK: ret
+; CHECK_FMA4: test_x86_fnmadd_ps_y_wide
+; CHECK_FMA4: vfnmaddps
+; CHECK_FMA4: vfnmaddps
+; CHECK_FMA4: ret
+define <16 x float> @test_x86_fnmadd_ps_y_wide(<16 x float> %a0, <16 x float> %a1, <16 x float> %a2) {
+  %x = fmul <16 x float> %a0, %a1
+  %res = fsub <16 x float> %a2, %x
+  ret <16 x float> %res
+}
+
+; CHECK: test_x86_fnmsub_ps_y_wide
+; CHECK: vfnmsub213ps
+; CHECK: vfnmsub213ps
+; CHECK: ret
+define <16 x float> @test_x86_fnmsub_ps_y_wide(<16 x float> %a0, <16 x float> %a1, <16 x float> %a2) {
+  %x = fmul <16 x float> %a0, %a1
+  %y = fsub <16 x float> <float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00>, %x
+  %res = fsub <16 x float> %y, %a2
+  ret <16 x float> %res
+}
+
+; CHECK: test_x86_fmadd_pd_y_wide
+; CHECK: vfmadd213pd
+; CHECK: vfmadd213pd
+; CHECK: ret
+; CHECK_FMA4: test_x86_fmadd_pd_y_wide
+; CHECK_FMA4: vfmaddpd
+; CHECK_FMA4: vfmaddpd
+; CHECK_FMA4: ret
+define <8 x double> @test_x86_fmadd_pd_y_wide(<8 x double> %a0, <8 x double> %a1, <8 x double> %a2) {
+  %x = fmul <8 x double> %a0, %a1
+  %res = fadd <8 x double> %x, %a2
+  ret <8 x double> %res
+}
+
+; CHECK: test_x86_fmsub_pd_y_wide
+; CHECK: vfmsub213pd
+; CHECK: vfmsub213pd
+; CHECK: ret
+; CHECK_FMA4: test_x86_fmsub_pd_y_wide
+; CHECK_FMA4: vfmsubpd
+; CHECK_FMA4: vfmsubpd
+; CHECK_FMA4: ret
+define <8 x double> @test_x86_fmsub_pd_y_wide(<8 x double> %a0, <8 x double> %a1, <8 x double> %a2) {
+  %x = fmul <8 x double> %a0, %a1
+  %res = fsub <8 x double> %x, %a2
+  ret <8 x double> %res
+}
diff --git a/test/CodeGen/X86/wide-fma-contraction.ll b/test/CodeGen/X86/wide-fma-contraction.ll
index d93f33b..7ee0fba 100644
--- a/test/CodeGen/X86/wide-fma-contraction.ll
+++ b/test/CodeGen/X86/wide-fma-contraction.ll
@@ -1,7 +1,9 @@
 ; RUN: llc -march=x86 -mattr=+fma4 -mtriple=x86_64-apple-darwin < %s | FileCheck %s
+; RUN: llc -march=x86 -mtriple=x86_64-apple-darwin < %s | FileCheck %s --check-prefix=CHECK-NOFMA
 
 ; CHECK: fmafunc
 define <16 x float> @fmafunc(<16 x float> %a, <16 x float> %b, <16 x float> %c) {
+
 ; CHECK-NOT: vmulps
 ; CHECK-NOT: vaddps
 ; CHECK: vfmaddps
@@ -10,11 +12,17 @@ define <16 x float> @fmafunc(<16 x float> %a, <16 x float> %b, <16 x float> %c)
 ; CHECK: vfmaddps
 ; CHECK-NOT: vmulps
 ; CHECK-NOT: vaddps
+
+; CHECK-NOFMA-NOT: calll
+; CHECK-NOFMA: vmulps
+; CHECK-NOFMA: vaddps
+; CHECK-NOFMA-NOT: calll
+; CHECK-NOFMA: vmulps
+; CHECK-NOFMA: vaddps
+; CHECK-NOFMA-NOT: calll
+
   %ret = tail call <16 x float> @llvm.fmuladd.v16f32(<16 x float> %a, <16 x float> %b, <16 x float> %c)
   ret <16 x float> %ret
 }
 
 declare <16 x float> @llvm.fmuladd.v16f32(<16 x float>, <16 x float>, <16 x float>) nounwind readnone
-
-
-