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| author | Sjoerd Meijer <sjoerd.meijer@arm.com> | 2018-10-17 10:05:44 +0000 |
|---|---|---|
| committer | Sjoerd Meijer <sjoerd.meijer@arm.com> | 2018-10-17 10:05:44 +0000 |
| commit | 64cfb74a61e097e64bc393008f44be53f942110e (patch) | |
| tree | dbfd355945dfe3923309fe1ab6bd366913daf733 | |
| parent | 7c8f91aa60600ffe3df9f6583432fa2cc38c5144 (diff) | |
| download | bcm5719-llvm-64cfb74a61e097e64bc393008f44be53f942110e.tar.gz bcm5719-llvm-64cfb74a61e097e64bc393008f44be53f942110e.zip | |
[ARM] Do not fuse VADD and VMUL, continued (2/2)
This is patch 2/2, following up on D53314, and is the functional change
to prevent fusing mul + add sequences into VFMAs.
Differential revision: https://reviews.llvm.org/D53315
llvm-svn: 344683
| -rw-r--r-- | llvm/lib/Target/ARM/ARMInstrInfo.td | 6 | ||||
| -rw-r--r-- | llvm/test/CodeGen/ARM/fusedMAC.ll | 9 |
2 files changed, 13 insertions, 2 deletions
diff --git a/llvm/lib/Target/ARM/ARMInstrInfo.td b/llvm/lib/Target/ARM/ARMInstrInfo.td index 529446ce809..fc8ed95ce8b 100644 --- a/llvm/lib/Target/ARM/ARMInstrInfo.td +++ b/llvm/lib/Target/ARM/ARMInstrInfo.td @@ -365,12 +365,14 @@ let RecomputePerFunction = 1 in { def UseMulOps : Predicate<"Subtarget->useMulOps()">; // Prefer fused MAC for fp mul + add over fp VMLA / VMLS if they are available. -// But only select them if more precision in FP computation is allowed. +// But only select them if more precision in FP computation is allowed, and when +// they are not slower than a mul + add sequence. // Do not use them for Darwin platforms. def UseFusedMAC : Predicate<"(TM.Options.AllowFPOpFusion ==" " FPOpFusion::Fast && " " Subtarget->hasVFP4()) && " - "!Subtarget->isTargetDarwin()">; + "!Subtarget->isTargetDarwin() &&" + "Subtarget->useFPVMLx()">; def HasFastVGETLNi32 : Predicate<"!Subtarget->hasSlowVGETLNi32()">; def HasSlowVGETLNi32 : Predicate<"Subtarget->hasSlowVGETLNi32()">; diff --git a/llvm/test/CodeGen/ARM/fusedMAC.ll b/llvm/test/CodeGen/ARM/fusedMAC.ll index 6f6cdc11491..6b922895b00 100644 --- a/llvm/test/CodeGen/ARM/fusedMAC.ll +++ b/llvm/test/CodeGen/ARM/fusedMAC.ll @@ -1,4 +1,8 @@ ; RUN: llc < %s -mtriple=armv7-eabi -mattr=+neon,+vfp4 -fp-contract=fast | FileCheck %s +; RUN: llc < %s -mtriple=arm-arm-eabi -mcpu=cortex-m7 -fp-contract=fast | FileCheck %s +; RUN: llc < %s -mtriple=arm-arm-eabi -mcpu=cortex-m4 -fp-contract=fast | FileCheck %s -check-prefix=DONT-FUSE +; RUN: llc < %s -mtriple=arm-arm-eabi -mcpu=cortex-m33 -fp-contract=fast | FileCheck %s -check-prefix=DONT-FUSE + ; Check generated fused MAC and MLS. define double @fusedMACTest1(double %d1, double %d2, double %d3) { @@ -12,6 +16,11 @@ define double @fusedMACTest1(double %d1, double %d2, double %d3) { define float @fusedMACTest2(float %f1, float %f2, float %f3) { ;CHECK-LABEL: fusedMACTest2: ;CHECK: vfma.f32 + +;DONT-FUSE-LABEL: fusedMACTest2: +;DONT-FUSE: vmul.f32 +;DONT-FUSE-NEXT: vadd.f32 + %1 = fmul float %f1, %f2 %2 = fadd float %1, %f3 ret float %2 |
