On Fri, Jul 21, 2017 at 12:41:41PM +0100, Jackson Woodruff wrote:
> Hi all,
>
> This merges vector multiplies and adds into a single mla instruction
> when the multiplication is done by a scalar.
>
> Currently, for the following:
>
> typedef int __attribute__((vector_size(16))) vec;
>
> vec
> mla0(vec v0, vec v1, vec v2)
> {
> return v0 + v1 * v2[0];
> }
>
> vec
> mla1(vec v0, vec v1, int v2)
> {
> return v0 + v1 * c;
> }
>
> The function `mla0` outputs a multiply accumulate by element
> instruction. `mla1` outputs two vector operations (multiply followed
> by add). That is, we currently have:
>
> mla0:
> mla v0.4s, v1.4s, v2.s[0]
> ret
>
> mla1:
> fmov s2, w0
> mul v1.4s, v1.4s, v2.s[0]
> add v0.4s, v1.4s, v0.4s
> ret
>
> This patch replaces this with something similar to `mla0`:
>
> mla1:
> fmov s2, w0
> mla v0.4s, v1.4s, v2.s[0]
>
> This is also done for the identical case for a multiply followed by
> a subtract of vectors with an integer operand on the multiply. Also
> add testcases for this.
>
> Bootstrap and testsuite run on aarch64. OK for trunk?
OK. I've committed this on your behalf as r250475.
There were two issues with your ChangeLog; there should be two spaces
between your name and your email address, and you had a pattern names
in the ChangeLog which did not appear in the patch. In the end, I
committed the patch with these ChangeLogs:
gcc/
2017-07-24 Jackson Woodruff <[email protected]>
* config/aarch64/aarch64-simd.md (aarch64_mla_elt_merge<mode>): New.
(aarch64_mls_elt_merge<mode>): Likewise.
gcc/testsuite/
2017-07-24 Jackson Woodruff <[email protected]>
* gcc.target/aarch64/simd/vmla_elem_1.c: New.
Thanks,
James
>
> Jackson
>
> Changelog entry:
>
> gcc/
>
> 2017-06-06 Jackson Woodruff <[email protected]>
>
> * config/aarch64/aarch64-simd.md (aarch64_mla_elt_merge<mode>,
>
> aarch64_mls_elt_merge<mode>, aarch64_fma4_elt_merge<mode>,
>
> aarch64_fnma_elt_merge<mode>): New define_insns to generate
>
> multiply accumulate instructions for unmerged
>
> multiply add vector instructions.
>
>
> gcc/testsuite/
>
> 2017-06-06 Jackson Woodruff <[email protected]>
>
> * gcc.target/aarch64/simd/vmla_elem_1.c: New.
>
