diff options
| author | Jim Grosbach <grosbach@apple.com> | 2009-10-31 22:57:36 +0000 |
|---|---|---|
| committer | Jim Grosbach <grosbach@apple.com> | 2009-10-31 22:57:36 +0000 |
| commit | 8cd0a8cb821263be4dc40b0b376ff02bfbd89f88 (patch) | |
| tree | 0548953203d7aa3bf81b1b5cb8a472d99116cc94 /lib | |
| parent | 1820ec5e7ae0f6581d1d7b10c3faa8561a57c3c1 (diff) | |
vml[as].f32 cause stalls in following advanced SIMD instructions. Avoid using
them for scalar floating point operations for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85697 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/ARM/ARMInstrNEON.td | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/lib/Target/ARM/ARMInstrNEON.td b/lib/Target/ARM/ARMInstrNEON.td index 822950c528..d22ec353fd 100644 --- a/lib/Target/ARM/ARMInstrNEON.td +++ b/lib/Target/ARM/ARMInstrNEON.td @@ -2841,13 +2841,16 @@ def VMULfd_sfp : N3VDs<1, 0, 0b00, 0b1101, 1, "vmul.f32", v2f32, v2f32, fmul,1>; def : N3VDsPat<fmul, VMULfd_sfp>; // Vector Multiply-Accumulate/Subtract used for single-precision FP -let neverHasSideEffects = 1 in -def VMLAfd_sfp : N3VDMulOps<0, 0, 0b00, 0b1101, 1, IIC_VMACD, "vmla.f32", v2f32,fmul,fadd>; -def : N3VDMulOpsPat<fmul, fadd, VMLAfd_sfp>; +// vml[as].f32 can cause 4-8 cycle stalls in following ASIMD instructions, so +// we want to avoid them for now. e.g., alternating vmla/vadd instructions. -let neverHasSideEffects = 1 in -def VMLSfd_sfp : N3VDMulOps<0, 0, 0b10, 0b1101, 1, IIC_VMACD, "vmls.f32", v2f32,fmul,fsub>; -def : N3VDMulOpsPat<fmul, fsub, VMLSfd_sfp>; +//let neverHasSideEffects = 1 in +//def VMLAfd_sfp : N3VDMulOps<0, 0, 0b00, 0b1101, 1, IIC_VMACD, "vmla.f32", v2f32,fmul,fadd>; +//def : N3VDMulOpsPat<fmul, fadd, VMLAfd_sfp>; + +//let neverHasSideEffects = 1 in +//def VMLSfd_sfp : N3VDMulOps<0, 0, 0b10, 0b1101, 1, IIC_VMACD, "vmls.f32", v2f32,fmul,fsub>; +//def : N3VDMulOpsPat<fmul, fsub, VMLSfd_sfp>; // Vector Absolute used for single-precision FP let neverHasSideEffects = 1 in |