/* Motorola m68k target-dependent support for GNU/Linux.
- Copyright 1996, 1998, 2000, 2001, 2002, 2003 Free Software Foundation,
- Inc.
+ Copyright 1996, 1998, 2000, 2001, 2002, 2003, 2004
+ Free Software Foundation, Inc.
This file is part of GDB.
#include "objfiles.h"
#include "symtab.h"
#include "m68k-tdep.h"
+#include "trad-frame.h"
+#include "frame-unwind.h"
\f
/* Offsets (in target ints) into jmp_buf. */
/* Get info about saved registers in sigtramp. */
-static struct m68k_sigtramp_info
+struct m68k_linux_sigtramp_info
+{
+ /* Address of sigcontext. */
+ CORE_ADDR sigcontext_addr;
+
+ /* Offset of registers in `struct sigcontext'. */
+ int *sc_reg_offset;
+};
+
+static struct m68k_linux_sigtramp_info
m68k_linux_get_sigtramp_info (struct frame_info *next_frame)
{
CORE_ADDR sp;
char buf[4];
- struct m68k_sigtramp_info info;
+ struct m68k_linux_sigtramp_info info;
frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
sp = extract_unsigned_integer (buf, 4);
return info;
}
-/* Extract from an array REGBUF containing the (raw) register state, a
- function return value of TYPE, and copy that, in virtual format,
- into VALBUF. */
+/* Signal trampolines. */
-static void
-m68k_linux_extract_return_value (struct type *type, struct regcache *regcache,
- void *valbuf)
+static struct trad_frame_cache *
+m68k_linux_sigtramp_frame_cache (struct frame_info *next_frame,
+ void **this_cache)
{
- int len = TYPE_LENGTH (type);
- char buf[M68K_MAX_REGISTER_SIZE];
-
- if (TYPE_CODE (type) == TYPE_CODE_STRUCT
- && TYPE_NFIELDS (type) == 1)
- {
- m68k_linux_extract_return_value (TYPE_FIELD_TYPE (type, 0), regcache,
- valbuf);
- return;
- }
-
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- regcache_raw_read (regcache, M68K_FP0_REGNUM, buf);
- convert_typed_floating (buf, builtin_type_m68881_ext, valbuf, type);
- }
- else if (TYPE_CODE (type) == TYPE_CODE_PTR)
- regcache_raw_read (regcache, M68K_A0_REGNUM, valbuf);
- else
- {
- if (len <= 4)
- {
- regcache_raw_read (regcache, M68K_D0_REGNUM, buf);
- memcpy (valbuf, buf + (4 - len), len);
- }
- else if (len <= 8)
- {
- regcache_raw_read (regcache, M68K_D0_REGNUM, buf);
- memcpy (valbuf, buf + (8 - len), len - 4);
- regcache_raw_read (regcache, M68K_D1_REGNUM,
- (char *) valbuf + (len - 4));
- }
- else
- internal_error (__FILE__, __LINE__,
- "Cannot extract return value of %d bytes long.", len);
- }
+ struct frame_id this_id;
+ struct trad_frame_cache *cache;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct m68k_linux_sigtramp_info info;
+ char buf[4];
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = trad_frame_cache_zalloc (next_frame);
+
+ /* FIXME: cagney/2004-05-01: This is is long standing broken code.
+ The frame ID's code address should be the start-address of the
+ signal trampoline and not the current PC within that
+ trampoline. */
+ frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
+ /* See the end of m68k_push_dummy_call. */
+ this_id = frame_id_build (extract_unsigned_integer (buf, 4) - 4 + 8,
+ frame_pc_unwind (next_frame));
+ trad_frame_set_id (cache, this_id);
+
+ info = m68k_linux_get_sigtramp_info (next_frame);
+
+ for (i = 0; i < M68K_NUM_REGS; i++)
+ if (info.sc_reg_offset[i] != -1)
+ trad_frame_set_reg_addr (cache, i,
+ info.sigcontext_addr + info.sc_reg_offset[i]);
+
+ *this_cache = cache;
+ return cache;
}
-/* Write into the appropriate registers a function return value stored
- in VALBUF of type TYPE, given in virtual format. */
+static void
+m68k_linux_sigtramp_frame_this_id (struct frame_info *next_frame,
+ void **this_cache,
+ struct frame_id *this_id)
+{
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_id (cache, this_id);
+}
static void
-m68k_linux_store_return_value (struct type *type, struct regcache *regcache,
- const void *valbuf)
+m68k_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)
{
- int len = TYPE_LENGTH (type);
-
- if (TYPE_CODE (type) == TYPE_CODE_STRUCT
- && TYPE_NFIELDS (type) == 1)
- {
- m68k_linux_store_return_value (TYPE_FIELD_TYPE (type, 0), regcache,
- valbuf);
- return;
- }
-
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- char buf[M68K_MAX_REGISTER_SIZE];
- convert_typed_floating (valbuf, type, buf, builtin_type_m68881_ext);
- regcache_raw_write (regcache, M68K_FP0_REGNUM, buf);
- }
- else if (TYPE_CODE (type) == TYPE_CODE_PTR)
- regcache_raw_write (regcache, M68K_A0_REGNUM, valbuf);
- else
- {
- if (len <= 4)
- regcache_raw_write_part (regcache, M68K_D0_REGNUM,
- 4 - len, len, valbuf);
- else if (len <= 8)
- {
- regcache_raw_write_part (regcache, M68K_D1_REGNUM, 8 - len,
- len - 4, valbuf);
- regcache_raw_write (regcache, M68K_D0_REGNUM,
- (char *) valbuf + (len - 4));
- }
- else
- internal_error (__FILE__, __LINE__,
- "Cannot store return value of %d bytes long.", len);
- }
+ /* Make sure we've initialized the cache. */
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_register (cache, next_frame, regnum, optimizedp, lvalp,
+ addrp, realnump, valuep);
}
-/* Extract from an array REGBUF containing the (raw) register state
- the address in which a function should return its structure value,
- as a CORE_ADDR. */
+static const struct frame_unwind m68k_linux_sigtramp_frame_unwind =
+{
+ SIGTRAMP_FRAME,
+ m68k_linux_sigtramp_frame_this_id,
+ m68k_linux_sigtramp_frame_prev_register
+};
-static CORE_ADDR
-m68k_linux_extract_struct_value_address (struct regcache *regcache)
+static const struct frame_unwind *
+m68k_linux_sigtramp_frame_sniffer (struct frame_info *next_frame)
{
- char buf[4];
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (m68k_linux_pc_in_sigtramp (pc, name))
+ return &m68k_linux_sigtramp_frame_unwind;
- regcache_cooked_read (regcache, M68K_A0_REGNUM, buf);
- return extract_unsigned_integer (buf, 4);
+ return NULL;
}
static void
tdep->jb_pc = M68K_LINUX_JB_PC;
tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE;
- tdep->get_sigtramp_info = m68k_linux_get_sigtramp_info;
- set_gdbarch_extract_return_value (gdbarch, m68k_linux_extract_return_value);
- set_gdbarch_store_return_value (gdbarch, m68k_linux_store_return_value);
- set_gdbarch_extract_struct_value_address (gdbarch,
- m68k_linux_extract_struct_value_address);
+ /* GNU/Linux uses a calling convention that's similar to SVR4. It
+ returns integer values in %d0/%di, pointer values in %a0 and
+ floating values in %fp0, just like SVR4, but uses %a1 to pass the
+ address to store a structure value. It also returns small
+ structures in registers instead of memory. */
+ m68k_svr4_init_abi (info, gdbarch);
+ tdep->struct_value_regnum = M68K_A1_REGNUM;
+ tdep->struct_return = reg_struct_return;
- set_gdbarch_pc_in_sigtramp (gdbarch, m68k_linux_pc_in_sigtramp);
+ frame_unwind_append_sniffer (gdbarch, m68k_linux_sigtramp_frame_sniffer);
/* Shared library handling. */
set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);