Re: [PATCH, testsuite, ARM] Check lr other than r3

[Richard Earnshaw <rearnsha@arm.com>]

On 03/11/14 08:18, Zhenqiang Chen wrote:
> Hi,
> 
> pr45701-1.c FAIL for all tests. The patch updates it to check lr other than
> r3, based on the comments in arm_compute_save_reg_mask,
> 
>   /* ...
>      Otherwise if we do not use the link register we do not need to save
>      it.  If we are pushing other registers onto the stack however, we
>      can save an instruction in the epilogue by pushing the link register
>      now and then popping it back into the PC.  This incurs extra memory
>      accesses though, so we only do it when optimizing for size, and only
>      if we know that we will not need a fancy return sequence.  */
> 
> The updated case PASS for Cortex-M0/M4 and Cortext-A15 (THUMB and ARM
> modes).
> 
> OK for trunk?
> 
> Thanks!
> -Zhenqiang
> 
> testsuite/ChangeLog:
> 2014-11-03  Zhenqiang Chen  <zhenqiang.chen@arm.com>
> 
> 	* gcc.target/arm/pr45701-1.c: Check LR used.

Have you checked that this doesn't cause regressions on ARMv4T?  I
suspect the code was originally intended to support targets where
interworking was not trivial.

R.

> 
> diff --git a/gcc/testsuite/gcc.target/arm/pr45701-1.c
> b/gcc/testsuite/gcc.target/arm/pr45701-1.c
> index 2c690d5..c087cfc 100644
> --- a/gcc/testsuite/gcc.target/arm/pr45701-1.c
> +++ b/gcc/testsuite/gcc.target/arm/pr45701-1.c
> @@ -1,7 +1,7 @@
>  /* { dg-do compile } */
>  /* { dg-skip-if "" { ! { arm_thumb1_ok || arm_thumb2_ok } } } */
>  /* { dg-options "-mthumb -Os" }  */
> -/* { dg-final { scan-assembler "push\t\{r3" } } */
> +/* { dg-final { scan-assembler "lr\}" } } */
>  /* { dg-final { scan-assembler-not "r8" } } */
>  
>  extern int hist_verify;
> 
> 
> 
> 
> 
>