diff options
| -rw-r--r-- | gdb/ChangeLog | 11 | ||||
| -rw-r--r-- | gdb/arc-tdep.c | 123 | ||||
| -rw-r--r-- | gdb/arc-tdep.h | 13 |
3 files changed, 147 insertions, 0 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 142278a..ba574d7 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2020-12-22 Anton Kolesov <anton.kolesov@synopsys.com> + + * arc-tdep.c (arc_make_sigtramp_frame_cache): New function. + (arc_sigtramp_frame_this_id): Likewise. + (arc_sigtramp_frame_prev_register): Likewise. + (arc_sigtramp_frame_sniffer): Likewise. + (arc_siftramp_frame_unwind): New global variable. + (arc_gdbarch_init): Use sigtramp capabilities. + (arc_dump_tdep): Print sigtramp fields. + * arc-tdep.h (gdbarch_tdep): Add sigtramp fields. + 2020-12-21 Tom Tromey <tom@tromey.com> * expression.h (enum noside): Move earlier. diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c index d18d3bc..846cc80 100644 --- a/gdb/arc-tdep.c +++ b/gdb/arc-tdep.c @@ -1844,6 +1844,104 @@ arc_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, reg->how = DWARF2_FRAME_REG_CFA; } +/* Signal trampoline frame unwinder. Allows frame unwinding to happen + from within signal handlers. */ + +static struct arc_frame_cache * +arc_make_sigtramp_frame_cache (struct frame_info *this_frame) +{ + if (arc_debug) + debug_printf ("arc: sigtramp_frame_cache\n"); + + struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (this_frame)); + + /* Allocate new frame cache instance and space for saved register info. */ + struct arc_frame_cache *cache = FRAME_OBSTACK_ZALLOC (struct arc_frame_cache); + cache->saved_regs = trad_frame_alloc_saved_regs (this_frame); + + /* Get the stack pointer and use it as the frame base. */ + cache->prev_sp = arc_frame_base_address (this_frame, NULL); + + /* If the ARC-private target-dependent info doesn't have a table of + offsets of saved register contents within an OS signal context + structure, then there is nothing to analyze. */ + if (tdep->sc_reg_offset == NULL) + return cache; + + /* Find the address of the sigcontext structure. */ + CORE_ADDR addr = tdep->sigcontext_addr (this_frame); + + /* For each register, if its contents have been saved within the + sigcontext structure, determine the address of those contents. */ + gdb_assert (tdep->sc_num_regs <= (ARC_LAST_REGNUM + 1)); + for (int i = 0; i < tdep->sc_num_regs; i++) + { + if (tdep->sc_reg_offset[i] != ARC_OFFSET_NO_REGISTER) + cache->saved_regs[i].addr = addr + tdep->sc_reg_offset[i]; + } + + return cache; +} + +/* Implement the "this_id" frame_unwind method for signal trampoline + frames. */ + +static void +arc_sigtramp_frame_this_id (struct frame_info *this_frame, + void **this_cache, struct frame_id *this_id) +{ + if (arc_debug) + debug_printf ("arc: sigtramp_frame_this_id\n"); + + if (*this_cache == NULL) + *this_cache = arc_make_sigtramp_frame_cache (this_frame); + + struct gdbarch *gdbarch = get_frame_arch (this_frame); + struct arc_frame_cache *cache = (struct arc_frame_cache *) *this_cache; + CORE_ADDR stack_addr = cache->prev_sp; + CORE_ADDR code_addr + = get_frame_register_unsigned (this_frame, gdbarch_pc_regnum (gdbarch)); + *this_id = frame_id_build (stack_addr, code_addr); +} + +/* Get a register from a signal handler frame. */ + +static struct value * +arc_sigtramp_frame_prev_register (struct frame_info *this_frame, + void **this_cache, int regnum) +{ + if (arc_debug) + debug_printf ("arc: sigtramp_frame_prev_register (regnum = %d)\n", regnum); + + /* Make sure we've initialized the cache. */ + if (*this_cache == NULL) + *this_cache = arc_make_sigtramp_frame_cache (this_frame); + + struct arc_frame_cache *cache = (struct arc_frame_cache *) *this_cache; + return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum); +} + +/* Frame sniffer for signal handler frame. Only recognize a frame if we + have a sigcontext_addr handler in the target dependency. */ + +static int +arc_sigtramp_frame_sniffer (const struct frame_unwind *self, + struct frame_info *this_frame, + void **this_cache) +{ + struct gdbarch_tdep *tdep; + + if (arc_debug) + debug_printf ("arc: sigtramp_frame_sniffer\n"); + + tdep = gdbarch_tdep (get_frame_arch (this_frame)); + + /* If we have a sigcontext_addr handler, then just return 1 (same as the + "default_frame_sniffer ()"). */ + return (tdep->sigcontext_addr != NULL && tdep->is_sigtramp != NULL + && tdep->is_sigtramp (this_frame)); +} + /* Structure defining the ARC ordinary frame unwind functions. Since we are the fallback unwinder, we use the default frame sniffer, which always accepts the frame. */ @@ -1859,6 +1957,21 @@ static const struct frame_unwind arc_frame_unwind = { NULL }; +/* Structure defining the ARC signal frame unwind functions. Custom + sniffer is used, because this frame must be accepted only in the right + context. */ + +static const struct frame_unwind arc_sigtramp_frame_unwind = { + SIGTRAMP_FRAME, + default_frame_unwind_stop_reason, + arc_sigtramp_frame_this_id, + arc_sigtramp_frame_prev_register, + NULL, + arc_sigtramp_frame_sniffer, + NULL, + NULL +}; + static const struct frame_base arc_normal_base = { &arc_frame_unwind, @@ -2272,6 +2385,7 @@ arc_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) /* Frame unwinders and sniffers. */ dwarf2_frame_set_init_reg (gdbarch, arc_dwarf2_frame_init_reg); dwarf2_append_unwinders (gdbarch); + frame_unwind_append_unwinder (gdbarch, &arc_sigtramp_frame_unwind); frame_unwind_append_unwinder (gdbarch, &arc_frame_unwind); frame_base_set_default (gdbarch, &arc_normal_base); @@ -2350,6 +2464,15 @@ arc_dump_tdep (struct gdbarch *gdbarch, struct ui_file *file) struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); fprintf_unfiltered (file, "arc_dump_tdep: jb_pc = %i\n", tdep->jb_pc); + + fprintf_unfiltered (file, "arc_dump_tdep: is_sigtramp = <%s>\n", + host_address_to_string (tdep->is_sigtramp)); + fprintf_unfiltered (file, "arc_dump_tdep: sigcontext_addr = <%s>\n", + host_address_to_string (tdep->sigcontext_addr)); + fprintf_unfiltered (file, "arc_dump_tdep: sc_reg_offset = <%s>\n", + host_address_to_string (tdep->sc_reg_offset)); + fprintf_unfiltered (file, "arc_dump_tdep: sc_num_regs = %d\n", + tdep->sc_num_regs); } /* This command accepts single argument - address of instruction to diff --git a/gdb/arc-tdep.h b/gdb/arc-tdep.h index 09fcbea..5ee5cf8 100644 --- a/gdb/arc-tdep.h +++ b/gdb/arc-tdep.h @@ -124,6 +124,19 @@ struct gdbarch_tdep /* Whether target has hardware (aka zero-delay) loops. */ bool has_hw_loops; + + /* Detect sigtramp. */ + bool (*is_sigtramp) (struct frame_info *); + + /* Get address of sigcontext for sigtramp. */ + CORE_ADDR (*sigcontext_addr) (struct frame_info *); + + /* Offset of registers in `struct sigcontext'. */ + const int *sc_reg_offset; + + /* Number of registers in sc_reg_offsets. Most likely a ARC_LAST_REGNUM, + but in theory it could be less, so it is kept separate. */ + int sc_num_regs; }; /* Utility functions used by other ARC-specific modules. */ |