Re: [PATCH] xtensa: Enforce return address saving when -Og is specified

[Max Filippov via Gcc-patches]

On Fri, Feb 17, 2023 at 8:54 PM Takayuki 'January June' Suwa
 wrote:
>
> Leaf function often omits saving its return address to the stack slot,
> and this feature often makes debugging very confusing, especially for
> stack dump analysis.
>
> gcc/ChangeLog:
>
> * config/xtensa/xtensa.cc (xtensa_call_save_reg): Change to return
> true if register A0 (return address register) when -Og is specified.
> ---
>  gcc/config/xtensa/xtensa.cc | 7 +--
>  1 file changed, 5 insertions(+), 2 deletions(-)

Regtested for target=xtensa-linux-uclibc, no new regressions.
Committed to master.

-- 
Thanks.
-- Max

[PATCH] xtensa: Enforce return address saving when -Og is specified

[Takayuki 'January June' Suwa via Gcc-patches]

Leaf function often omits saving its return address to the stack slot,
and this feature often makes debugging very confusing, especially for
stack dump analysis.

gcc/ChangeLog:

* config/xtensa/xtensa.cc (xtensa_call_save_reg): Change to return
true if register A0 (return address register) when -Og is specified.
---
 gcc/config/xtensa/xtensa.cc | 7 +--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/gcc/config/xtensa/xtensa.cc b/gcc/config/xtensa/xtensa.cc
index d987f1dfede..1d9e4d1561a 100644
--- a/gcc/config/xtensa/xtensa.cc
+++ b/gcc/config/xtensa/xtensa.cc
@@ -3224,8 +3224,11 @@ xtensa_call_save_reg (int regno)
 return false;
 
   if (regno == A0_REG)
-return crtl->profile || !crtl->is_leaf || crtl->calls_eh_return ||
-  df_regs_ever_live_p (regno);
+/* Ensure the return address to be saved to the stack slot in order
+   to assist stack dump analysis when -Og is specified.  */
+return optimize_debug
+  || crtl->profile || !crtl->is_leaf || crtl->calls_eh_return
+  || df_regs_ever_live_p (regno);
 
   if (crtl->calls_eh_return && IN_RANGE (regno, 2, 3))
 return true;
-- 
2.30.2