aboutsummaryrefslogtreecommitdiff
path: root/gdb/alpha-linux-tdep.c
diff options
context:
space:
mode:
authorRichard Henderson <rth@redhat.com>2003-05-29 23:02:53 +0000
committerRichard Henderson <rth@redhat.com>2003-05-29 23:02:53 +0000
commitd2427a719bedac1dff31c9566234062b887f7cce (patch)
tree86718ca1fa7d90f24d797903d856d01382b6b93a /gdb/alpha-linux-tdep.c
parente9ecd949862fcccc0af5829d1b5c09b596de91f3 (diff)
downloadgdb-d2427a719bedac1dff31c9566234062b887f7cce.zip
gdb-d2427a719bedac1dff31c9566234062b887f7cce.tar.gz
gdb-d2427a719bedac1dff31c9566234062b887f7cce.tar.bz2
* alpha-linux-tdep.c (alpha_linux_sigtramp_offset_1): New.
(alpha_linux_sigtramp_offset): Use it. Make static. (alpha_linux_sigcontext_addr): Handle __NR_rt_sigreturn; update for new frame model. * alpha-mdebug-tdep.c: New file. * alpha-osf1-tdep.c (alpha_call_dummy_address): Move from alpha-tdep.c. (alpha_osf1_init_abi): Install it. * alpha-tdep.c (PROC_*): Move to alpha-mdebug-tdep.c. (linked_proc_desc_table): Remove. (alpha_frame_past_sigtramp_frame): Remove. (alpha_dynamic_sigtramp_offset): Remove. (ALPHA_PROC_SIGTRAMP_MAGIC): Remove. (alpha_proc_desc_is_dyn_sigtramp): Remove. (alpha_set_proc_desc_is_dyn_sigtramp): Remove. (push_sigtramp_desc): Remove. (alpha_cannot_fetch_register): Use ALPHA_FP_REGNUM. (alpha_cannot_store_register): Likewise. (alpha_sigcontext_addr): Remove. (alpha_find_saved_regs): Remove. (alpha_frame_init_saved_regs): Remove. (alpha_init_frame_pc_first): Remove. (read_next_frame_reg): Remove. (alpha_frame_saved_pc): Remove. (alpha_saved_pc_after_call): Remove. (temp_proc_desc, temp_saved_regs): Remove. (alpha_about_to_return): Remove. (cached_proc_desc): Remove. (alpha_frame_chain): Remove. (alpha_print_extra_frame_info): Remove. (alpha_init_extra_frame_info): Remove. (alpha_frame_locals_address): Remove. (alpha_frame_args_address): Remove. (alpha_push_arguments): Use ALPHA_REGISTER_BYTES not sizeof CORE_ADDR. (alpha_push_dummy_frame): Remove. (alpha_pop_frame): Remove. (alpha_after_prologue): Rename from after_prologue; remove mdebug bits. (alpha_read_insn): New. (alpha_skip_prologue): Merge alpha_skip_prologue_internal; adjust for different insn encodings. (alpha_in_lenient_prologue): Remove. (struct alpha_sigtramp_unwind_cache): New. (alpha_sigtramp_frame_unwind_cache): New. (alpha_sigtramp_register_address): New. (alpha_sigtramp_frame_this_id): New. (alpha_sigtramp_frame_prev_register): New. (alpha_sigtramp_frame_unwind): New. (alpha_sigtramp_frame_p): New. (struct alpha_heuristic_unwind_cache): New. (alpha_heuristic_proc_start): Rename from heuristic_proc_start; don't count nop insns that occur between functions. (alpha_heuristic_frame_unwind_cache): New; incorporate much of heuristic_proc_desc, but without the mdebug wrapping. (alpha_heuristic_frame_this_id): New. (alpha_heuristic_frame_prev_register): New. (alpha_heuristic_frame_unwind): New. (alpha_heuristic_frame_p): New. (alpha_heuristic_frame_base_address): New. (alpha_heuristic_frame_base): New. (alpha_unwind_dummy_id): New. (alpha_unwind_pc): New. (alpha_gdbarch_init): Don't set skip_sigtramp_frame. Kill use of frame related deprecated initializations; install replacements. (alpha_dump_tdep): Remove. * alpha-tdep.h (struct gdbarch_tdep): Remove skip_sigtramp_frame. (alpha_read_insn, alpha_after_prologue, alpha_heuristic_frame_unwind_cache, alpha_heuristic_frame_this_id, alpha_heuristic_frame_prev_register, alpha_heuristic_frame_base_address, alpha_mdebug_init_abi): Declare. * config/alpha/alpha-linux.mt (TDEPFILES): Add alpha-mdebug-tdep.o. * config/alpha/tm-alpha.h (PRINT_EXTRA_FRAME_INFO): Remove. * config/alpha/tm-alphalinux.h (SIGTRAMP_START, SIGTRAMP_END): Remove.
Diffstat (limited to 'gdb/alpha-linux-tdep.c')
-rw-r--r--gdb/alpha-linux-tdep.c134
1 files changed, 81 insertions, 53 deletions
diff --git a/gdb/alpha-linux-tdep.c b/gdb/alpha-linux-tdep.c
index c5d7481..e89a0fa 100644
--- a/gdb/alpha-linux-tdep.c
+++ b/gdb/alpha-linux-tdep.c
@@ -23,93 +23,121 @@
#include "gdbcore.h"
#include "value.h"
#include "osabi.h"
+#include "gdb_assert.h"
#include "alpha-tdep.h"
-/* Under GNU/Linux, signal handler invocations can be identified by the
- designated code sequence that is used to return from a signal
+/* Under GNU/Linux, signal handler invocations can be identified by
+ the designated code sequence that is used to return from a signal
handler. In particular, the return address of a signal handler
- points to the following sequence (the first instruction is quadword
- aligned):
-
- bis $30,$30,$16
- addq $31,0x67,$0
- call_pal callsys
-
- Each instruction has a unique encoding, so we simply attempt to
- match the instruction the pc is pointing to with any of the above
- instructions. If there is a hit, we know the offset to the start
- of the designated sequence and can then check whether we really are
- executing in a designated sequence. If not, -1 is returned,
- otherwise the offset from the start of the desingated sequence is
- returned.
-
- There is a slight chance of false hits: code could jump into the
- middle of the designated sequence, in which case there is no
- guarantee that we are in the middle of a sigreturn syscall. Don't
- think this will be a problem in praxis, though. */
-LONGEST
-alpha_linux_sigtramp_offset (CORE_ADDR pc)
+ points to a sequence that copies $sp to $16, loads $0 with the
+ appropriate syscall number, and finally enters the kernel.
+
+ This is somewhat complicated in that:
+ (1) the expansion of the "mov" assembler macro has changed over
+ time, from "bis src,src,dst" to "bis zero,src,dst",
+ (2) the kernel has changed from using "addq" to "lda" to load the
+ syscall number,
+ (3) there is a "normal" sigreturn and an "rt" sigreturn which
+ has a different stack layout.
+*/
+
+static long
+alpha_linux_sigtramp_offset_1 (CORE_ADDR pc)
{
- unsigned int i[3], w;
- long off;
+ switch (alpha_read_insn (pc))
+ {
+ case 0x47de0410: /* bis $30,$30,$16 */
+ case 0x47fe0410: /* bis $31,$30,$16 */
+ return 0;
- if (read_memory_nobpt (pc, (char *) &w, 4) != 0)
- return -1;
+ case 0x43ecf400: /* addq $31,103,$0 */
+ case 0x201f0067: /* lda $0,103($31) */
+ case 0x201f015f: /* lda $0,351($31) */
+ return 4;
+
+ case 0x00000083: /* call_pal callsys */
+ return 8;
- off = -1;
- switch (w)
- {
- case 0x47de0410:
- off = 0;
- break; /* bis $30,$30,$16 */
- case 0x43ecf400:
- off = 4;
- break; /* addq $31,0x67,$0 */
- case 0x00000083:
- off = 8;
- break; /* call_pal callsys */
default:
return -1;
}
+}
+
+static LONGEST
+alpha_linux_sigtramp_offset (CORE_ADDR pc)
+{
+ long i, off;
+
+ if (pc & 3)
+ return -1;
+
+ /* Guess where we might be in the sequence. */
+ off = alpha_linux_sigtramp_offset_1 (pc);
+ if (off < 0)
+ return -1;
+
+ /* Verify that the other two insns of the sequence are as we expect. */
pc -= off;
- if (pc & 0x7)
+ for (i = 0; i < 12; i += 4)
{
- /* designated sequence is not quadword aligned */
- return -1;
+ if (i == off)
+ continue;
+ if (alpha_linux_sigtramp_offset_1 (pc + i) != i)
+ return -1;
}
- if (read_memory_nobpt (pc, (char *) i, sizeof (i)) != 0)
- return -1;
-
- if (i[0] == 0x47de0410 && i[1] == 0x43ecf400 && i[2] == 0x00000083)
- return off;
- return -1;
+ return off;
}
static int
alpha_linux_pc_in_sigtramp (CORE_ADDR pc, char *func_name)
{
- return (alpha_linux_sigtramp_offset (pc) >= 0);
+ return alpha_linux_sigtramp_offset (pc) >= 0;
}
static CORE_ADDR
-alpha_linux_sigcontext_addr (struct frame_info *frame)
+alpha_linux_sigcontext_addr (struct frame_info *next_frame)
{
- return (get_frame_base (frame) - 0x298); /* sizeof(struct sigcontext) */
+ CORE_ADDR pc;
+ ULONGEST sp;
+ long off;
+
+ pc = frame_pc_unwind (next_frame);
+ frame_unwind_unsigned_register (next_frame, ALPHA_SP_REGNUM, &sp);
+
+ off = alpha_linux_sigtramp_offset (pc);
+ gdb_assert (off >= 0);
+
+ /* __NR_rt_sigreturn has a couple of structures on the stack. This is:
+
+ struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+ };
+
+ offsetof (struct rt_sigframe, uc.uc_mcontext);
+ */
+ if (alpha_read_insn (pc - off + 4) == 0x201f015f)
+ return sp + 176;
+
+ /* __NR_sigreturn has the sigcontext structure at the top of the stack. */
+ return sp;
}
static void
alpha_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ struct gdbarch_tdep *tdep;
+
+ alpha_mdebug_init_abi (info, gdbarch);
set_gdbarch_pc_in_sigtramp (gdbarch, alpha_linux_pc_in_sigtramp);
+ tdep = gdbarch_tdep (gdbarch);
tdep->dynamic_sigtramp_offset = alpha_linux_sigtramp_offset;
tdep->sigcontext_addr = alpha_linux_sigcontext_addr;
-
tdep->jb_pc = 2;
tdep->jb_elt_size = 8;
}