[LLVMdev] fmac generation for cortex-a9
sebastien.deldon at st.com
Thu Nov 8 04:57:13 PST 2012
Thanks for your answer but -mcpu=cortex-a9 -mattr=+vfp4 doesn' t enable fused mac generation for me.
I would like just to understand why -mtriple=armv7-eabi enables it while -mcpu=cortex-a9 seems to disable it ?
> -----Original Message-----
> From: Anitha Boyapati [mailto:anitha.boyapati at gmail.com]
> Sent: Thursday, November 08, 2012 10:22 AM
> To: Sebastien DELDON-GNB
> Cc: llvmdev at cs.uiuc.edu
> Subject: Re: [LLVMdev] fmac generation for cortex-a9
> On 8 November 2012 13:56, Sebastien DELDON-GNB
> <sebastien.deldon at st.com> wrote:
> > Hi all,
> > I've a .ll code that use double precision fmul/fadd or fmul/fsub. When
> > I compile it using llc -mcpu=cortex-a9 I couldn't get vmla/vmls
> > generated even using -fp-contract=fast, but when I use option
> > -mtriple=armv7-eabi instead of -mcpu=cortex-a9 fused mac are
> generated. Can someone explain me why ?
> Perhaps you need to use some attributes. -mattr=+vfp4 Check fusedMAC.ll
> from ARM codegen tests.
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