[gcc(refs/users/meissner/heads/work008)] [Arm] Modify default tuning of armv8.1-m.main to use Cortex-M55

[gcc(refs/users/meissner/heads/work008)] [Arm] Modify default tuning of armv8.1-m.main to use Cortex-M55

[Michael Meissner]

https://gcc.gnu.org/g:079b13f64cee9d6c208c9c490ab6b35055c299ce

commit 079b13f64cee9d6c208c9c490ab6b35055c299ce
Author: Omar Tahir <omar.tahir@arm.com>
Date:   Tue Aug 4 17:35:18 2020 +0100

    [Arm] Modify default tuning of armv8.1-m.main to use Cortex-M55
    
    Previously, compiling with -march=armv8.1-m.main would tune for
    Cortex-M7.
    However, the Cortex-M7 only supports up to Armv7e-M. The Cortex-M55 is
    the earliest CPU that supports Armv8.1-M Mainline so is more appropriate.
    This also has the effect of changing the branch cost function used, which
    will be necessary to correctly prioritise conditional instructions over branches
    in the rest of this patch series.
    
    Regression tested on arm-none-eabi.
    
    gcc/ChangeLog
    
    2020-08-04  Omar Tahir  <omar.tahir@arm.com>
    
            * config/arm/arm-cpus.in (armv8.1-m.main): Tune for Cortex-M55.

Diff:
---
 gcc/config/arm/arm-cpus.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm-cpus.in b/gcc/config/arm/arm-cpus.in
index 728be500b80..c98f8ede8fd 100644
--- a/gcc/config/arm/arm-cpus.in
+++ b/gcc/config/arm/arm-cpus.in
@@ -716,7 +716,7 @@ begin arch armv8-r
 end arch armv8-r
 
 begin arch armv8.1-m.main
- tune for cortex-m7
+ tune for cortex-m55
  tune flags CO_PROC
  base 8M_MAIN
  profile M