Re: [PATCH, AArch64] Negate with Compare instruction

[Richard Earnshaw <rearnsha at arm dot com>]

On 19/04/13 12:41, Hurugalawadi, Naveen wrote:
> Hi,
>
> Please find attached the patch that implements Negate with Carry
> instruction for aarch64 target.
>
> Please review the same and let me know if there should be any
> modifications in the patch.
>
> Build and tested on aarch64-thunder-elf (using Cavium's internal
> simulator). No new regressions.
>
> Thanks,
> Naveen
>
> gcc/
>
> 2013-04-19   Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
>
>          * config/aarch64/aarch64.md (*ngc<mode>): New pattern.
> 	(*ngcsi_uxtw): New pattern.
>
> gcc/testsuite/
>
> 2013-04-19   Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
>
>          * gcc.target/aarch64/ngc.c: New.

diff -uprN 
NCDtools/thunder/gits/gcc/gcc-orig/testsuite/gcc.target/aarch64/ngc.c 
NCDtools/thunder/gits/gcc/gcc/testsuite/gcc.target/aarch64/ngc.c
> --- NCDtools/thunder/gits/gcc/gcc-orig/testsuite/gcc.target/aarch64/ngc.c	1970-01-01 05:30:00.000000000 +0530
> +++ NCDtools/thunder/gits/gcc/gcc/testsuite/gcc.target/aarch64/ngc.c	2013-04-19 16:48:44.457544465 +0530
> @@ -0,0 +1,67 @@
> +/* { dg-do run } */
> +/* { dg-options "-O2 --save-temps -fno-inline" } */
> +
> +extern void abort (void);
> +typedef unsigned int u32;
> +
> +u32
> +ngc_si (u32 a, u32 b, u32 c, u32 d)
> +{
> +  /* { dg-final { scan-assembler "ngc\tw\[0-9\]+, w\[0-9\]+\n" } } */
> +  a = -b - (c < d);
> +  return a;
> +}
> +
> +typedef unsigned long long u64;
> +
> +u64
> +ngc_si_tst (u64 a, u32 b, u32 c, u32 d)
> +{
> +  /* { dg-final { scan-assembler "ngc\tw\[0-9\]+, w\[0-9\]+\n" } } */

This and the preceding scan are the same pattern.  So if either passes 
you'll fail to detect a failure in the other.

R.