From 0dbe1904b3c847fd11b7c448a82b54abb5c3fc05 Mon Sep 17 00:00:00 2001 From: Mark Kettenis Date: Sun, 21 Aug 2005 10:47:48 +0000 Subject: [PATCH] * ppcobsd-tdep.c: Include "frame.h" and "frame-unwind.h". Don't include "tramp-frame.h". (ppcobsd_sigtramp_cache_init): Remove function. (ppcobsd_sigtramp): Remove variable. (ppcobsd_page_size, ppcobsd_sigreturn_offset): New variables. (ppcobsd_sigtramp_p): New function. (ppcobsd_sigtramp_frame_cache, ppcobsd_sigtramp_frame_this_id) (ppcobsd_sigtramp_frame_prev_register): New functions. (ppcobsd_sigtramp_frame_unwind): New variable. (ppcobsd_sigtramp_frame_sniffer): New function. (ppcobsd_init_abi): Adjust to register new sigtramp sniffer instead of the old one. * Makefile.in (ppcobsd-tdep.o): Update dependencies. --- gdb/ChangeLog | 14 ++++ gdb/Makefile.in | 4 +- gdb/ppcobsd-tdep.c | 159 ++++++++++++++++++++++++++++++++++++--------- 3 files changed, 146 insertions(+), 31 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1f15d5df69..af374c94fd 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,19 @@ 2005-08-21 Mark Kettenis + * ppcobsd-tdep.c: Include "frame.h" and "frame-unwind.h". Don't + include "tramp-frame.h". + (ppcobsd_sigtramp_cache_init): Remove function. + (ppcobsd_sigtramp): Remove variable. + (ppcobsd_page_size, ppcobsd_sigreturn_offset): New variables. + (ppcobsd_sigtramp_p): New function. + (ppcobsd_sigtramp_frame_cache, ppcobsd_sigtramp_frame_this_id) + (ppcobsd_sigtramp_frame_prev_register): New functions. + (ppcobsd_sigtramp_frame_unwind): New variable. + (ppcobsd_sigtramp_frame_sniffer): New function. + (ppcobsd_init_abi): Adjust to register new sigtramp sniffer + instead of the old one. + * Makefile.in (ppcobsd-tdep.o): Update dependencies. + * infcall.c (call_function_by_hand): For RETURN_VALUE_ABI_RETURNS_ADDRESS and RETURN_VALUE_ABI_PRESERVES_ADDRESS, use gdbarch_return_value to diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 0330b73d43..9a46f634ad 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -2382,8 +2382,8 @@ ppcobsd-nat.o: ppcobsd-nat.c $(defs_h) $(gdbcore_h) $(inferior_h) \ $(regcache_h) $(ppc_tdep_h) $(ppcobsd_tdep_h) $(inf_ptrace_h) \ $(bsd_kvm_h) ppcobsd-tdep.o: ppcobsd-tdep.c $(defs_h) $(arch_utils_h) $(floatformat_h) \ - $(osabi_h) $(regcache_h) $(regset_h) $(trad_frame_h) \ - $(tramp_frame_h) $(gdb_assert_h) $(gdb_string_h) $(ppc_tdep_h) \ + $(frame_h) $(frame_unwind_h) $(osabi_h) $(regcache_h) $(regset_h) \ + $(trad_frame_h) $(gdb_assert_h) $(gdb_string_h) $(ppc_tdep_h) \ $(ppcobsd_tdep_h) $(solib_svr4_h) ppc-sysv-tdep.o: ppc-sysv-tdep.c $(defs_h) $(gdbcore_h) $(inferior_h) \ $(regcache_h) $(value_h) $(gdb_string_h) $(gdb_assert_h) \ diff --git a/gdb/ppcobsd-tdep.c b/gdb/ppcobsd-tdep.c index c2d542e164..cfb57e9bd7 100644 --- a/gdb/ppcobsd-tdep.c +++ b/gdb/ppcobsd-tdep.c @@ -22,11 +22,13 @@ #include "defs.h" #include "arch-utils.h" #include "floatformat.h" +#include "frame.h" +#include "frame-unwind.h" #include "osabi.h" #include "regcache.h" #include "regset.h" +#include "symtab.h" #include "trad-frame.h" -#include "tramp-frame.h" #include "gdb_assert.h" #include "gdb_string.h" @@ -116,55 +118,154 @@ ppcobsd_regset_from_core_section (struct gdbarch *gdbarch, /* Signal trampolines. */ -static void -ppcobsd_sigtramp_cache_init (const struct tramp_frame *self, - struct frame_info *next_frame, - struct trad_frame_cache *this_cache, - CORE_ADDR func) +/* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page + in virtual memory. The randomness makes it somewhat tricky to + detect it, but fortunately we can rely on the fact that the start + of the sigtramp routine is page-aligned. We recognize the + trampoline by looking for the code that invokes the sigreturn + system call. The offset where we can find that code varies from + release to release. + + By the way, the mapping mentioned above is read-only, so you cannot + place a breakpoint in the signal trampoline. */ + +/* Default page size. */ +static const int ppcobsd_page_size = 4096; + +/* Offset for sigreturn(2). */ +static const int ppcobsd_sigreturn_offset[] = { + 0x98, /* OpenBSD 3.8 */ + 0x0c, /* OpenBSD 3.2 */ + -1 +}; + +static int +ppcobsd_sigtramp_p (struct frame_info *next_frame) +{ + CORE_ADDR pc = frame_pc_unwind (next_frame); + CORE_ADDR start_pc = (pc & ~(ppcobsd_page_size - 1)); + const int *offset; + char *name; + + find_pc_partial_function (pc, &name, NULL, NULL); + if (name) + return 0; + + for (offset = ppcobsd_sigreturn_offset; *offset != -1; offset++) + { + gdb_byte buf[2 * PPC_INSN_SIZE]; + unsigned long insn; + + if (!safe_frame_unwind_memory (next_frame, start_pc + *offset, + buf, sizeof buf)) + continue; + + /* Check for "li r0,SYS_sigreturn". */ + insn = extract_unsigned_integer (buf, PPC_INSN_SIZE); + if (insn != 0x38000067) + continue; + + /* Check for "sc". */ + insn = extract_unsigned_integer (buf + PPC_INSN_SIZE, PPC_INSN_SIZE); + if (insn != 0x44000002) + continue; + + return 1; + } + + return 0; +} + +static struct trad_frame_cache * +ppcobsd_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache) { struct gdbarch *gdbarch = get_frame_arch (next_frame); struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); - CORE_ADDR addr, base; + struct trad_frame_cache *cache; + CORE_ADDR addr, base, func; + gdb_byte buf[PPC_INSN_SIZE]; + unsigned long insn, sigcontext_offset; int i; + if (*this_cache) + return *this_cache; + + cache = trad_frame_cache_zalloc (next_frame); + *this_cache = cache; + + func = frame_pc_unwind (next_frame); + func &= ~(ppcobsd_page_size - 1); + if (!safe_frame_unwind_memory (next_frame, func, buf, sizeof buf)) + return cache; + + /* Calculate the offset where we can find `struct sigcontext'. We + base our calculation on the amount of stack space reserved by the + first instruction of the signal trampoline. */ + insn = extract_unsigned_integer (buf, PPC_INSN_SIZE); + sigcontext_offset = (0x10000 - (insn & 0x0000ffff)) + 8; + base = frame_unwind_register_unsigned (next_frame, SP_REGNUM); - addr = base + 0x18 + 2 * tdep->wordsize; + addr = base + sigcontext_offset + 2 * tdep->wordsize; for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize) { int regnum = i + tdep->ppc_gp0_regnum; - trad_frame_set_reg_addr (this_cache, regnum, addr); + trad_frame_set_reg_addr (cache, regnum, addr); } - trad_frame_set_reg_addr (this_cache, tdep->ppc_lr_regnum, addr); + trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr); addr += tdep->wordsize; - trad_frame_set_reg_addr (this_cache, tdep->ppc_cr_regnum, addr); + trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr); addr += tdep->wordsize; - trad_frame_set_reg_addr (this_cache, tdep->ppc_xer_regnum, addr); + trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr); addr += tdep->wordsize; - trad_frame_set_reg_addr (this_cache, tdep->ppc_ctr_regnum, addr); + trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr); addr += tdep->wordsize; - trad_frame_set_reg_addr (this_cache, PC_REGNUM, addr); /* SRR0? */ + trad_frame_set_reg_addr (cache, PC_REGNUM, addr); /* SRR0? */ addr += tdep->wordsize; /* Construct the frame ID using the function start. */ - trad_frame_set_id (this_cache, frame_id_build (base, func)); + trad_frame_set_id (cache, frame_id_build (base, func)); + + return cache; } -static const struct tramp_frame ppcobsd_sigtramp = +static void +ppcobsd_sigtramp_frame_this_id (struct frame_info *next_frame, + void **this_cache, struct frame_id *this_id) +{ + struct trad_frame_cache *cache = + ppcobsd_sigtramp_frame_cache (next_frame, this_cache); + + trad_frame_get_id (cache, this_id); +} + +static void +ppcobsd_sigtramp_frame_prev_register (struct frame_info *next_frame, + void **this_cache, int regnum, + int *optimizedp, enum lval_type *lvalp, + CORE_ADDR *addrp, int *realnump, + gdb_byte *valuep) { + struct trad_frame_cache *cache = + ppcobsd_sigtramp_frame_cache (next_frame, this_cache); + + trad_frame_get_register (cache, next_frame, regnum, + optimizedp, lvalp, addrp, realnump, valuep); +} + +static const struct frame_unwind ppcobsd_sigtramp_frame_unwind = { SIGTRAMP_FRAME, - 4, - { - { 0x3821fff0, -1 }, /* add r1,r1,-16 */ - { 0x4e800021, -1 }, /* blrl */ - { 0x38610018, -1 }, /* addi r3,r1,24 */ - { 0x38000067, -1 }, /* li r0,103 */ - { 0x44000002, -1 }, /* sc */ - { 0x38000001, -1 }, /* li r0,1 */ - { 0x44000002, -1 }, /* sc */ - { TRAMP_SENTINEL_INSN, -1 } - }, - ppcobsd_sigtramp_cache_init + ppcobsd_sigtramp_frame_this_id, + ppcobsd_sigtramp_frame_prev_register }; + +static const struct frame_unwind * +ppcobsd_sigtramp_frame_sniffer (struct frame_info *next_frame) +{ + if (ppcobsd_sigtramp_p (next_frame)) + return &ppcobsd_sigtramp_frame_unwind; + + return NULL; +} static void @@ -184,7 +285,7 @@ ppcobsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_regset_from_core_section (gdbarch, ppcobsd_regset_from_core_section); - tramp_frame_prepend_unwinder (gdbarch, &ppcobsd_sigtramp); + frame_unwind_append_sniffer (gdbarch, ppcobsd_sigtramp_frame_sniffer); } -- 2.34.1