Displaying 5 results from an estimated 5 matches for "vmfa".
Did you mean:
vma
2013 Dec 19
0
[LLVMdev] LLVM ARM VMLA instruction
> As per Renato comment above, vmla instruction is NEON instruction while vmfa is VFP instruction. Correct me if i am wrong on this.
My version of the ARM architecture reference manual (v7 A & R) lists
versions requiring NEON and versions requiring VFP. (Section
A8.8.337). Split in just the way you'd expect (SIMD variants need
NEON).
> It may seem that total numb...
2013 Dec 19
4
[LLVMdev] LLVM ARM VMLA instruction
...d (which is a NEON instruction)
>
> I get a VFP vmla here rather than a NEON one (clang -target
> armv7-linux-gnueabihf -mcpu=cortex-a15): "vmla.f32 s0, s1, s2". Are
> you seeing something different?
>
As per Renato comment above, vmla instruction is NEON instruction while
vmfa is VFP instruction. Correct me if i am wrong on this.
>
> > However, if gcc emits vmla (NEON) instruction with cortex-a8 then
> shouldn't
> > LLVM also emit vmla (NEON) instruction?
>
> It appears we've decided in the past that vmla just isn't worth it on
>...
2013 Dec 19
0
[LLVMdev] LLVM ARM VMLA instruction
> cortex-a8 vfpv4 with ffp-contract=fast : vfma instruction emitted ( this
> seems a bug to me!! If cortex-a8 doesn't come with vfpv4 then vfma
> instructions generated will be invalid )
If I'm understanding correctly, you've specifically told it this
Cortex-A8 *does* come with vfpv4. Those kinds of odd combinations can
be useful sometimes (if only for tests), so I'm not
2013 Dec 19
1
[LLVMdev] LLVM ARM VMLA instruction
On Thu, Dec 19, 2013 at 2:43 PM, Tim Northover <t.p.northover at gmail.com>wrote:
> > As per Renato comment above, vmla instruction is NEON instruction while
> vmfa is VFP instruction. Correct me if i am wrong on this.
>
> My version of the ARM architecture reference manual (v7 A & R) lists
> versions requiring NEON and versions requiring VFP. (Section
> A8.8.337). Split in just the way you'd expect (SIMD variants need
> NEON).
>
I w...
2013 Dec 19
3
[LLVMdev] LLVM ARM VMLA instruction
Hi all,
Thanks for the info. Few observations from my side :
LLVM :
cortex-a8 vfpv3 : no vmla or vfma instruction emitted
cortex-a8 vfpv4 : no vmla or vfma instruction emitted (This is invalid
though as cortex-a8 does not have vfpv4)
cortex-a8 vfpv4 with ffp-contract=fast : vfma instruction emitted ( this
seems a bug to me!! If cortex-a8 doesn't come with vfpv4 then vfma
instructions