diff options
Diffstat (limited to 'gdb/mips-tdep.c')
| -rw-r--r-- | gdb/mips-tdep.c | 38 |
1 files changed, 34 insertions, 4 deletions
diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c index 9a3c7fb..ebf7c48 100644 --- a/gdb/mips-tdep.c +++ b/gdb/mips-tdep.c @@ -3009,6 +3009,38 @@ mips_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr) return align_down (addr, 16); } +/* Implement the "push_dummy_call" gdbarch method. */ + +static CORE_ADDR +mips_push_dummy_code (struct gdbarch *gdbarch, CORE_ADDR sp, + CORE_ADDR funaddr, struct value **args, + int nargs, struct type *value_type, + CORE_ADDR *real_pc, CORE_ADDR *bp_addr, + struct regcache *regcache) +{ + CORE_ADDR nop_addr; + static gdb_byte nop_insn[] = { 0, 0, 0, 0 }; + + /* Reserve enough room on the stack for our breakpoint instruction. */ + *bp_addr = sp - sizeof (nop_insn); + + /* The breakpoint layer automatically adjusts the address of + breakpoints inserted in a branch delay slot. With enough + bad luck, the 4 bytes located just before our breakpoint + instruction could look like a branch instruction, and thus + trigger the adjustement, and break the function call entirely. + So, we reserve those 4 bytes and write a nop instruction + to prevent that from happening. */ + nop_addr = *bp_addr - sizeof (nop_insn); + write_memory (nop_addr, nop_insn, sizeof (nop_insn)); + sp = mips_frame_align (gdbarch, nop_addr); + + /* Inferior resumes at the function entry point. */ + *real_pc = funaddr; + + return sp; +} + static CORE_ADDR mips_eabi_push_dummy_call (struct gdbarch *gdbarch, struct value *function, struct regcache *regcache, CORE_ADDR bp_addr, @@ -6906,10 +6938,8 @@ mips_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) /* MIPS version of CALL_DUMMY. */ - /* NOTE: cagney/2003-08-05: Eventually call dummy location will be - replaced by a command, and all targets will default to on stack - (regardless of the stack's execute status). */ - set_gdbarch_call_dummy_location (gdbarch, AT_SYMBOL); + set_gdbarch_call_dummy_location (gdbarch, ON_STACK); + set_gdbarch_push_dummy_code (gdbarch, mips_push_dummy_code); set_gdbarch_frame_align (gdbarch, mips_frame_align); set_gdbarch_convert_register_p (gdbarch, mips_convert_register_p); |