sh: Setup the frame register in asm code

In order to use DWARF unwinder info the frame register has to contain a
valid value. Whilst GCC takes care of this for C code, we have to do it
ourselves for assembly.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Matt Fleming 2009-08-02 22:33:26 +01:00 committed by Paul Mundt
parent bd353861c7
commit 0b930489b8
3 changed files with 14 additions and 0 deletions

View file

@ -108,3 +108,15 @@
#else
# define PREF(x) nop
#endif
/*
* Macro for use within assembly. Because the DWARF unwinder
* needs to use the frame register to unwind the stack, we
* need to setup r14 with the value of the stack pointer as
* the return address is usually on the stack somewhere.
*/
.macro setup_frame_reg
#ifdef CONFIG_DWARF_UNWINDER
mov r15, r14
#endif
.endm

View file

@ -137,6 +137,7 @@ ENTRY(tlb_protection_violation_store)
mov #1, r5
call_dpf:
setup_frame_reg
mov.l 1f, r0
mov r5, r8
mov.l @r0, r6

View file

@ -285,6 +285,7 @@ ret_from_fork:
* system calls and debug traps through their respective jump tables.
*/
ENTRY(system_call)
setup_frame_reg
#if !defined(CONFIG_CPU_SH2)
mov.l 1f, r9
mov.l @r9, r8 ! Read from TRA (Trap Address) Register