Re: [AArch64] Fix vqtb[lx][234] on big-endian

[James Greenhalgh <james dot greenhalgh at arm dot com>]

On Fri, Nov 06, 2015 at 02:49:38PM +0100, Christophe Lyon wrote:
> Hi,
> 
> As mentioned by James a few weeks ago, the vqtbl[lx][234] intrinsics
> are failing on aarch64_be.
> 
> The attached patch fixes them, and rewrites them using new builtins
> instead of inline assembly.
> 
> I wondered about the names of the new builtins, I hope I got them
> right: qtbl3, qtbl4, qtbx3, qtbx4 with v8qi and v16qi modes.
> 
> I have modified the existing aarch64_tbl3v8qi and aarch64_tbx4v8qi to
> use <mode> and share the code with the v16qi variants.
> 
> In arm_neon.h, I moved the rewritten intrinsics to the bottom of the
> file, in alphabetical order, although the comment says "Start of
> optimal implementations in approved order": the previous ones really
> seem to be in alphabetical order.
> 
> And I added a new testcase, skipped for arm* targets.
> 
> This has been tested on aarch64-none-elf and aarch64_be-none-elf
> targets, using the Foundation model.
> 
> OK?

Hi Christophe,

Thanks for this. With this patch I think we can finally say that
aarch64_be Neon intrinsics are in as good a state as aarch64 Neon
intrinsics. On our internal testsuite the pass rate is now equivalent
between the two. I'm very grateful for your work in this area!

This patch is OK for trunk.

Thanks again,
James

> 
> Christophe.

> 2015-11-06  Christophe Lyon  <christophe.lyon@linaro.org>
> 
> 	gcc/testsuite/
> 	* gcc.target/aarch64/advsimd-intrinsics/vqtbX.c: New test.
> 
> 	gcc/
> 	* config/aarch64/aarch64-simd-builtins.def: Update builtins
> 	tables: add tbl3v16qi, qtbl[34]*, tbx4v16qi, qtbx[34]*.
> 	* config/aarch64/aarch64-simd.md (aarch64_tbl3v8qi): Rename to...
> 	(aarch64_tbl3<mode>) ... this, which supports v16qi too.
> 	(aarch64_tbx4v8qi): Rename to...
> 	aarch64_tbx4<mode>): ... this.
> 	(aarch64_qtbl3<mode>): New pattern.
> 	(aarch64_qtbx3<mode>): New pattern.
> 	(aarch64_qtbl4<mode>): New pattern.
> 	(aarch64_qtbx4<mode>): New pattern.
> 	* config/aarch64/arm_neon.h (vqtbl2_s8, vqtbl2_u8, vqtbl2_p8)
> 	(vqtbl2q_s8, vqtbl2q_u8, vqtbl2q_p8, vqtbl3_s8, vqtbl3_u8)
> 	(vqtbl3_p8, vqtbl3q_s8, vqtbl3q_u8, vqtbl3q_p8, vqtbl4_s8)
> 	(vqtbl4_u8, vqtbl4_p8, vqtbl4q_s8, vqtbl4q_u8, vqtbl4q_p8)
> 	(vqtbx2_s8, vqtbx2_u8, vqtbx2_p8, vqtbx2q_s8, vqtbx2q_u8)
> 	(vqtbx2q_p8, vqtbx3_s8, vqtbx3_u8, vqtbx3_p8, vqtbx3q_s8)
> 	(vqtbx3q_u8, vqtbx3q_p8, vqtbx4_s8, vqtbx4_u8, vqtbx4_p8)
> 	(vqtbx4q_s8, vqtbx4q_u8, vqtbx4q_p8): Rewrite using builtin
> 	functions.