find_pc_partial_function (pc, &name, NULL, NULL);
/* If we have NAME, we can optimize the search. The trampolines are
- named __restore and __restore_rt. However, they aren't dynamically
- exported from the shared C library, so the trampoline may appear to
- be part of the preceding function. This should always be sigaction,
- __sigaction, or __libc_sigaction (all aliases to the same function). */
+ named __sigreturn_stub and __rt_sigreturn_stub. However, they
+ aren't dynamically exported from the shared C library, so the
+ trampoline may appear to be part of the preceding function. This
+ should always be sigaction, __sigaction, or __libc_sigaction (all
+ aliases to the same function). */
if (name == NULL || strstr (name, "sigaction") != NULL)
return (sparc32_linux_sigtramp_start (next_frame) != 0
|| sparc32_linux_rt_sigtramp_start (next_frame) != 0);
- return (strcmp ("__restore", name) == 0
- || strcmp ("__restore_rt", name) == 0);
+ return (strcmp ("__sigreturn_stub", name) == 0
+ || strcmp ("__rt_sigreturn_stub", name) == 0);
}
static struct sparc_frame_cache *
cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+ /* Offsets from <bits/sigcontext.h> */
+
cache->saved_regs[SPARC32_PSR_REGNUM].addr = sigcontext_addr + 0;
cache->saved_regs[SPARC32_PC_REGNUM].addr = sigcontext_addr + 4;
cache->saved_regs[SPARC32_NPC_REGNUM].addr = sigcontext_addr + 8;
Boston, MA 02111-1307, USA. */
#include "defs.h"
+#include "frame.h"
+#include "frame-unwind.h"
#include "gdbarch.h"
#include "osabi.h"
#include "solib-svr4.h"
+#include "symtab.h"
+#include "trad-frame.h"
+
+#include "gdb_assert.h"
+#include "gdb_string.h"
#include "sparc64-tdep.h"
+/* The instruction sequence for RT signals is
+ mov __NR_rt_sigreturn, %g1 ! hex: 0x82102065
+ ta 0x6d ! hex: 0x91d0206d
+
+ The effect is to call the system call rt_sigreturn.
+ Note that 64-bit binaries only use this RT signal return method. */
+
+#define LINUX64_RT_SIGTRAMP_INSN0 0x82102065
+#define LINUX64_RT_SIGTRAMP_INSN1 0x91d0206d
+
+/* If PC is in a sigtramp routine consisting of the instructions
+ LINUX64_RT_SIGTRAMP_INSN0 and LINUX64_RT_SIGTRAMP_INSN1, return
+ the address of the start of the routine. Otherwise, return 0. */
+
+static CORE_ADDR
+sparc64_linux_sigtramp_start (struct frame_info *next_frame)
+{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ ULONGEST word0, word1;
+ unsigned char buf[8]; /* Two instructions. */
+
+ /* We only recognize a signal trampoline if PC is at the start of
+ one of the instructions. We optimize for finding the PC at the
+ start of the instruction sequence, as will be the case when the
+ trampoline is not the first frame on the stack. We assume that
+ in the case where the PC is not at the start of the instruction
+ sequence, there will be a few trailing readable bytes on the
+ stack. */
+
+ if (!safe_frame_unwind_memory (next_frame, pc, buf, sizeof buf))
+ return 0;
+
+ word0 = extract_unsigned_integer (buf, 4);
+ if (word0 != LINUX64_RT_SIGTRAMP_INSN0)
+ {
+ if (word0 != LINUX64_RT_SIGTRAMP_INSN1)
+ return 0;
+
+ pc -= 4;
+ if (!safe_frame_unwind_memory (next_frame, pc, buf, sizeof buf))
+ return 0;
+
+ word0 = extract_unsigned_integer (buf, 4);
+ }
+
+ word1 = extract_unsigned_integer (buf + 4, 4);
+ if (word0 != LINUX64_RT_SIGTRAMP_INSN0
+ || word1 != LINUX64_RT_SIGTRAMP_INSN1)
+ return 0;
+
+ return pc;
+}
+
+static int
+sparc64_linux_sigtramp_p (struct frame_info *next_frame)
+{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+
+ /* If we have NAME, we can optimize the search. The trampolines is
+ named __rt_sigreturn_stub. However, is isn't dynamically exported
+ from the shared C library, so the trampoline may appear to be part
+ of the preceding function. This should always be sigaction,
+ __sigaction, or __libc_sigaction (all aliases to the same function). */
+ if (name == NULL || strstr (name, "sigaction") != NULL)
+ return (sparc64_linux_sigtramp_start (next_frame) != 0);
+
+ return (strcmp ("__rt_sigreturn_stub", name) == 0);
+}
+
+static struct sparc_frame_cache *
+sparc64_linux_sigtramp_frame_cache (struct frame_info *next_frame,
+ void **this_cache)
+{
+ struct sparc_frame_cache *cache;
+ CORE_ADDR sigcontext_addr, addr;
+ int regnum;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = sparc_frame_cache (next_frame, this_cache);
+ gdb_assert (cache == *this_cache);
+
+ regnum = SPARC_SP_REGNUM;
+ cache->base = frame_unwind_register_unsigned (next_frame, regnum);
+ if (cache->base & 1)
+ cache->base += BIAS;
+
+ regnum = SPARC_O1_REGNUM;
+ sigcontext_addr = frame_unwind_register_unsigned (next_frame, regnum);
+
+ /* If this is a RT signal trampoline, adjust SIGCONTEXT_ADDR
+ accordingly. */
+ addr = sparc64_linux_sigtramp_start (next_frame);
+ if (addr)
+ sigcontext_addr += 128;
+ else
+ addr = frame_func_unwind (next_frame);
+
+ cache->pc = addr;
+
+ cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+
+ /* Offsets from <bits/sigcontext.h> */
+
+ /* Since %g0 is always zero, keep the identity encoding. */
+ for (addr = sigcontext_addr + 8, regnum = SPARC_G1_REGNUM;
+ regnum <= SPARC_O7_REGNUM; regnum++, addr += 8)
+ cache->saved_regs[regnum].addr = addr;
+
+ cache->saved_regs[SPARC64_STATE_REGNUM].addr = addr + 0;
+ cache->saved_regs[SPARC64_PC_REGNUM].addr = addr + 8;
+ cache->saved_regs[SPARC64_NPC_REGNUM].addr = addr + 16;
+ cache->saved_regs[SPARC64_Y_REGNUM].addr = addr + 24;
+ cache->saved_regs[SPARC64_FPRS_REGNUM].addr = addr + 28;
+
+ for (regnum = SPARC_L0_REGNUM, addr = cache->base;
+ regnum <= SPARC_I7_REGNUM; regnum++, addr += 8)
+ cache->saved_regs[regnum].addr = addr;
+
+ return cache;
+}
+
+static void
+sparc64_linux_sigtramp_frame_this_id (struct frame_info *next_frame,
+ void **this_cache,
+ struct frame_id *this_id)
+{
+ struct sparc_frame_cache *cache =
+ sparc64_linux_sigtramp_frame_cache (next_frame, this_cache);
+
+ (*this_id) = frame_id_build (cache->base, cache->pc);
+}
+
+static void
+sparc64_linux_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, void *valuep)
+{
+ struct sparc_frame_cache *cache =
+ sparc64_linux_sigtramp_frame_cache (next_frame, this_cache);
+
+ trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum,
+ optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind sparc64_linux_sigtramp_frame_unwind =
+{
+ SIGTRAMP_FRAME,
+ sparc64_linux_sigtramp_frame_this_id,
+ sparc64_linux_sigtramp_frame_prev_register
+};
+
+static const struct frame_unwind *
+sparc64_linux_sigtramp_frame_sniffer (struct frame_info *next_frame)
+{
+ if (sparc64_linux_sigtramp_p (next_frame))
+ return &sparc64_linux_sigtramp_frame_unwind;
+
+ return NULL;
+}
+\f
static void
sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ frame_unwind_append_sniffer (gdbarch, sparc64_linux_sigtramp_frame_sniffer);
+
/* GNU/Linux is very similar to Solaris ... */
sparc64_sol2_init_abi (info, gdbarch);
projects / external / binutils.git / commitdiff