/* Target-dependent code for the MIPS architecture, for GDB, the GNU Debugger.
- Copyright 1988, 1989, 1990, 1991 Free Software Foundation, Inc.
+ Copyright 1988, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
-#include <stdio.h>
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#endif
#include <sys/param.h>
-#include <sys/dir.h>
#include <signal.h>
#include <sys/ioctl.h>
#include "gdbcore.h"
+#include "symfile.h"
+#include "objfiles.h"
#ifndef MIPSMAGIC
#ifdef MIPSEL
#include <sys/stat.h>
\f
-#define PROC_LOW_ADDR(proc) ((proc)->adr) /* least address */
-#define PROC_HIGH_ADDR(proc) ((proc)->pad2) /* upper address bound */
-#define PROC_FRAME_OFFSET(proc) ((proc)->framesize)
-#define PROC_FRAME_REG(proc) ((proc)->framereg)
-#define PROC_REG_MASK(proc) ((proc)->regmask)
-#define PROC_FREG_MASK(proc) ((proc)->fregmask)
-#define PROC_REG_OFFSET(proc) ((proc)->regoffset)
-#define PROC_FREG_OFFSET(proc) ((proc)->fregoffset)
-#define PROC_PC_REG(proc) ((proc)->pcreg)
-#define PROC_SYMBOL(proc) (*(struct symbol**)&(proc)->isym)
+/* Some MIPS boards don't support floating point, so we permit the
+ user to turn it off. */
+int mips_fpu = 1;
+
+/* Heuristic_proc_start may hunt through the text section for a long
+ time across a 2400 baud serial line. Allows the user to limit this
+ search. */
+static unsigned int heuristic_fence_post = 0;
+
+#define PROC_LOW_ADDR(proc) ((proc)->pdr.adr) /* least address */
+#define PROC_HIGH_ADDR(proc) ((proc)->pdr.iline) /* upper address bound */
+#define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
+#define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
+#define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
+#define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
+#define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
+#define PROC_FREG_OFFSET(proc) ((proc)->pdr.fregoffset)
+#define PROC_PC_REG(proc) ((proc)->pdr.pcreg)
+#define PROC_SYMBOL(proc) (*(struct symbol**)&(proc)->pdr.isym)
#define _PROC_MAGIC_ 0x0F0F0F0F
-#define PROC_DESC_IS_DUMMY(proc) ((proc)->isym == _PROC_MAGIC_)
-#define SET_PROC_DESC_IS_DUMMY(proc) ((proc)->isym = _PROC_MAGIC_)
+#define PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym == _PROC_MAGIC_)
+#define SET_PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym = _PROC_MAGIC_)
struct linked_proc_info
{
struct mips_extra_func_info info;
struct linked_proc_info *next;
-} * linked_proc_desc_table = NULL;
+} *linked_proc_desc_table = NULL;
\f
#define READ_FRAME_REG(fi, regno) read_next_frame_reg((fi)->next, regno)
-int
+static int
read_next_frame_reg(fi, regno)
FRAME fi;
int regno;
{
-#define SIGFRAME_BASE sizeof(struct sigcontext)
-#define SIGFRAME_PC_OFF (-SIGFRAME_BASE+ 2*sizeof(int))
-#define SIGFRAME_SP_OFF (-SIGFRAME_BASE+32*sizeof(int))
-#define SIGFRAME_RA_OFF (-SIGFRAME_BASE+34*sizeof(int))
+ /* If it is the frame for sigtramp we have a complete sigcontext
+ immediately below the frame and we get the saved registers from there.
+ If the stack layout for sigtramp changes we might have to change these
+ constants and the companion fixup_sigtramp in mipsread.c */
+#ifndef SIGFRAME_BASE
+#define SIGFRAME_BASE 0x12c /* sizeof(sigcontext) */
+#define SIGFRAME_PC_OFF (-SIGFRAME_BASE + 2 * 4)
+#define SIGFRAME_REGSAVE_OFF (-SIGFRAME_BASE + 3 * 4)
+#endif
for (; fi; fi = fi->next)
if (in_sigtramp(fi->pc, 0)) {
- /* No idea if this code works. --PB. */
int offset;
if (regno == PC_REGNUM) offset = SIGFRAME_PC_OFF;
- else if (regno == RA_REGNUM) offset = SIGFRAME_RA_OFF;
- else if (regno == SP_REGNUM) offset = SIGFRAME_SP_OFF;
+ else if (regno < 32) offset = SIGFRAME_REGSAVE_OFF + regno * 4;
else return 0;
return read_memory_integer(fi->frame + offset, 4);
}
mips_frame_saved_pc(frame)
FRAME frame;
{
- mips_extra_func_info_t proc_desc = (mips_extra_func_info_t)frame->proc_desc;
+ mips_extra_func_info_t proc_desc = frame->proc_desc;
int pcreg = proc_desc ? PROC_PC_REG(proc_desc) : RA_REGNUM;
+
if (proc_desc && PROC_DESC_IS_DUMMY(proc_desc))
return read_memory_integer(frame->frame - 4, 4);
-#if 0
- /* If in the procedure prologue, RA_REGNUM might not have been saved yet.
- * Assume non-leaf functions start with:
- * addiu $sp,$sp,-frame_size
- * sw $ra,ra_offset($sp)
- * This if the pc is pointing at either of these instructions,
- * then $ra hasn't been trashed.
- * If the pc has advanced beyond these two instructions,
- * then $ra has been saved.
- * critical, and much more complex. Handling $ra is enough to get
- * a stack trace, but some register values with be wrong.
- */
- if (frame->proc_desc && frame->pc < PROC_LOW_ADDR(proc_desc) + 8)
- return read_register(pcreg);
-#endif
+
return read_next_frame_reg(frame, pcreg);
}
static struct mips_extra_func_info temp_proc_desc;
static struct frame_saved_regs temp_saved_regs;
-CORE_ADDR heuristic_proc_start(pc)
+/* This fencepost looks highly suspicious to me. Removing it also
+ seems suspicious as it could affect remote debugging across serial
+ lines. */
+
+static CORE_ADDR
+heuristic_proc_start(pc)
CORE_ADDR pc;
{
-
CORE_ADDR start_pc = pc;
- CORE_ADDR fence = start_pc - 10000;
- if (fence < VM_MIN_ADDRESS) fence = VM_MIN_ADDRESS;
+ CORE_ADDR fence = start_pc - heuristic_fence_post;
+
+ if (start_pc == 0) return 0;
+
+ if (heuristic_fence_post == UINT_MAX
+ || fence < VM_MIN_ADDRESS)
+ fence = VM_MIN_ADDRESS;
+
/* search back for previous return */
for (start_pc -= 4; ; start_pc -= 4)
- if (start_pc < fence) return 0;
+ if (start_pc < fence)
+ {
+ /* It's not clear to me why we reach this point when
+ stop_soon_quietly, but with this test, at least we
+ don't print out warnings for every child forked (eg, on
+ decstation). 22apr93 rich@cygnus.com. */
+ if (!stop_soon_quietly)
+ {
+ if (fence == VM_MIN_ADDRESS)
+ warning("Hit beginning of text section without finding");
+ else
+ warning("Hit heuristic-fence-post without finding");
+
+ warning("enclosing function for pc 0x%x", pc);
+ }
+
+ return 0;
+ }
else if (ABOUT_TO_RETURN(start_pc))
break;
return start_pc;
}
-mips_extra_func_info_t
+static mips_extra_func_info_t
heuristic_proc_desc(start_pc, limit_pc, next_frame)
CORE_ADDR start_pc, limit_pc;
FRAME next_frame;
if (start_pc == 0) return NULL;
bzero(&temp_proc_desc, sizeof(temp_proc_desc));
bzero(&temp_saved_regs, sizeof(struct frame_saved_regs));
+ PROC_LOW_ADDR(&temp_proc_desc) = start_pc;
+
if (start_pc + 200 < limit_pc) limit_pc = start_pc + 200;
restart:
frame_size = 0;
unsigned long word;
int status;
- status = read_memory_nobpt (cur_pc, &word, 4);
+ status = read_memory_nobpt (cur_pc, (char *)&word, 4);
if (status) memory_error (status, cur_pc);
+ SWAP_TARGET_AND_HOST (&word, sizeof (word));
if ((word & 0xFFFF0000) == 0x27bd0000) /* addiu $sp,$sp,-i */
frame_size += (-word) & 0xFFFF;
else if ((word & 0xFFFF0000) == 0x23bd0000) /* addu $sp,$sp,-i */
return &temp_proc_desc;
}
-mips_extra_func_info_t
+static mips_extra_func_info_t
find_proc_desc(pc, next_frame)
CORE_ADDR pc;
FRAME next_frame;
{
mips_extra_func_info_t proc_desc;
- extern struct block *block_for_pc();
- struct block *b = block_for_pc(pc);
-
+ struct block *b = block_for_pc(pc);
struct symbol *sym =
- b ? lookup_symbol(".gdbinfo.", b, LABEL_NAMESPACE, 0, NULL) : NULL;
- if (sym != NULL)
+ b ? lookup_symbol(MIPS_EFI_SYMBOL_NAME, b, LABEL_NAMESPACE, 0, NULL) : NULL;
+
+ if (sym)
{
/* IF this is the topmost frame AND
* (this proc does not have debugging information OR
* the PC is in the procedure prologue)
- * THEN create a "hueristic" proc_desc (by analyzing
+ * THEN create a "heuristic" proc_desc (by analyzing
* the actual code) to replace the "official" proc_desc.
*/
- proc_desc = (struct mips_extra_func_info *)sym->value.value;
+ proc_desc = (mips_extra_func_info_t)SYMBOL_VALUE(sym);
if (next_frame == NULL) {
struct symtab_and_line val;
struct symbol *proc_symbol =
PROC_DESC_IS_DUMMY(proc_desc) ? 0 : PROC_SYMBOL(proc_desc);
+
if (proc_symbol) {
val = find_pc_line (BLOCK_START
(SYMBOL_BLOCK_VALUE(proc_symbol)),
}
else
{
+ /* Is linked_proc_desc_table really necessary? It only seems to be used
+ by procedure call dummys. However, the procedures being called ought
+ to have their own proc_descs, and even if they don't,
+ heuristic_proc_desc knows how to create them! */
+
register struct linked_proc_info *link;
for (link = linked_proc_desc_table; link; link = link->next)
if (PROC_LOW_ADDR(&link->info) <= pc
mips_extra_func_info_t cached_proc_desc;
-FRAME_ADDR mips_frame_chain(frame)
+FRAME_ADDR
+mips_frame_chain(frame)
FRAME frame;
{
- extern CORE_ADDR startup_file_start; /* From blockframe.c */
mips_extra_func_info_t proc_desc;
CORE_ADDR saved_pc = FRAME_SAVED_PC(frame);
- if (startup_file_start)
- { /* has at least the __start symbol */
- if (saved_pc == 0 || !outside_startup_file (saved_pc)) return 0;
- }
- else
- { /* This hack depends on the internals of __start. */
- /* We also assume the breakpoints are *not* inserted */
- if (saved_pc == 0
- || read_memory_integer (saved_pc + 8, 4) & 0xFC00003F == 0xD)
- return 0; /* break */
- }
+
+ if (saved_pc == 0 || inside_entry_file (saved_pc))
+ return 0;
+
proc_desc = find_proc_desc(saved_pc, frame);
- if (!proc_desc) return 0;
+ if (!proc_desc)
+ return 0;
+
cached_proc_desc = proc_desc;
return read_next_frame_reg(frame, PROC_FRAME_REG(proc_desc))
- + PROC_FRAME_OFFSET(proc_desc);
+ + PROC_FRAME_OFFSET(proc_desc);
}
void
/* Use proc_desc calculated in frame_chain */
mips_extra_func_info_t proc_desc = fci->next ? cached_proc_desc :
find_proc_desc(fci->pc, fci->next);
+
fci->saved_regs = (struct frame_saved_regs*)
obstack_alloc (&frame_cache_obstack, sizeof(struct frame_saved_regs));
bzero(fci->saved_regs, sizeof(struct frame_saved_regs));
fci->proc_desc =
- proc_desc == &temp_proc_desc ? (char*)NULL : (char*)proc_desc;
+ proc_desc == &temp_proc_desc ? 0 : proc_desc;
if (proc_desc)
{
int ireg;
int kernel_trap = PROC_REG_MASK(proc_desc) & 1;
/* Fixup frame-pointer - only needed for top frame */
- /* This may not be quite right, if procedure has a real frame register */
+ /* This may not be quite right, if proc has a real frame register */
if (fci->pc == PROC_LOW_ADDR(proc_desc))
- fci->frame = read_register (SP_REGNUM);
+ fci->frame = read_register (SP_REGNUM);
else
- fci->frame = READ_FRAME_REG(fci, PROC_FRAME_REG(proc_desc))
- + PROC_FRAME_OFFSET(proc_desc);
+ fci->frame = READ_FRAME_REG(fci, PROC_FRAME_REG(proc_desc))
+ + PROC_FRAME_OFFSET(proc_desc);
if (proc_desc == &temp_proc_desc)
*fci->saved_regs = temp_saved_regs;
for (ireg = 31; mask; --ireg, mask <<= 1)
if (mask & 0x80000000)
{
- fci->saved_regs->regs[32+ireg] = reg_position;
+ fci->saved_regs->regs[FP0_REGNUM+ireg] = reg_position;
reg_position -= 4;
}
}
fci->saved_regs->regs[PC_REGNUM] = fci->saved_regs->regs[RA_REGNUM];
}
- if (fci->next == 0)
- supply_register(FP_REGNUM, &fci->frame);
+}
+
+/* MIPS stack frames are almost impenetrable. When execution stops,
+ we basically have to look at symbol information for the function
+ that we stopped in, which tells us *which* register (if any) is
+ the base of the frame pointer, and what offset from that register
+ the frame itself is at.
+
+ This presents a problem when trying to examine a stack in memory
+ (that isn't executing at the moment), using the "frame" command. We
+ don't have a PC, nor do we have any registers except SP.
+
+ This routine takes two arguments, SP and PC, and tries to make the
+ cached frames look as if these two arguments defined a frame on the
+ cache. This allows the rest of info frame to extract the important
+ arguments without difficulty. */
+
+FRAME
+setup_arbitrary_frame (argc, argv)
+ int argc;
+ FRAME_ADDR *argv;
+{
+ if (argc != 2)
+ error ("MIPS frame specifications require two arguments: sp and pc");
+
+ return create_new_frame (argv[0], argv[1]);
}
-CORE_ADDR mips_push_arguments(nargs, args, sp, struct_return, struct_addr)
+CORE_ADDR
+mips_push_arguments(nargs, args, sp, struct_return, struct_addr)
int nargs;
value *args;
CORE_ADDR sp;
write_memory(sp + m_arg->offset, m_arg->contents, m_arg->len);
if (struct_return) {
buf = struct_addr;
- write_memory(sp, &buf, sizeof(CORE_ADDR));
-}
+ write_memory(sp, (char *)&buf, sizeof(CORE_ADDR));
+ }
return sp;
}
* Saved D18 (i.e. F19, F18)
* ...
* Saved D0 (i.e. F1, F0)
- * CALL_DUMMY (subroutine stub; see m-mips.h)
+ * CALL_DUMMY (subroutine stub; see tm-mips.h)
* Parameter build area (not yet implemented)
* (low memory)
*/
PROC_REG_MASK(proc_desc) = GEN_REG_SAVE_MASK;
- PROC_FREG_MASK(proc_desc) = FLOAT_REG_SAVE_MASK;
+ PROC_FREG_MASK(proc_desc) = mips_fpu ? FLOAT_REG_SAVE_MASK : 0;
PROC_REG_OFFSET(proc_desc) = /* offset of (Saved R31) from FP */
-sizeof(long) - 4 * SPECIAL_REG_SAVE_COUNT;
PROC_FREG_OFFSET(proc_desc) = /* offset of (Saved D18) from FP */
if (PROC_REG_MASK(proc_desc) & (1 << ireg))
{
buffer = read_register (ireg);
- write_memory (save_address, &buffer, sizeof(REGISTER_TYPE));
+ write_memory (save_address, (char *)&buffer, sizeof(REGISTER_TYPE));
save_address -= 4;
}
- /* save floating-points registers */
- save_address = sp + PROC_FREG_OFFSET(proc_desc);
+ /* save floating-points registers starting with high order word */
+ save_address = sp + PROC_FREG_OFFSET(proc_desc) + 4;
for (ireg = 32; --ireg >= 0; )
if (PROC_FREG_MASK(proc_desc) & (1 << ireg))
{
buffer = read_register (ireg + FP0_REGNUM);
- write_memory (save_address, &buffer, 4);
+ write_memory (save_address, (char *)&buffer, 4);
save_address -= 4;
}
write_register (PUSH_FP_REGNUM, sp);
PROC_FRAME_REG(proc_desc) = PUSH_FP_REGNUM;
PROC_FRAME_OFFSET(proc_desc) = 0;
buffer = read_register (PC_REGNUM);
- write_memory (sp - 4, &buffer, sizeof(REGISTER_TYPE));
+ write_memory (sp - 4, (char *)&buffer, sizeof(REGISTER_TYPE));
buffer = read_register (HI_REGNUM);
- write_memory (sp - 8, &buffer, sizeof(REGISTER_TYPE));
+ write_memory (sp - 8, (char *)&buffer, sizeof(REGISTER_TYPE));
buffer = read_register (LO_REGNUM);
- write_memory (sp - 12, &buffer, sizeof(REGISTER_TYPE));
- buffer = read_register (FCRCS_REGNUM);
- write_memory (sp - 16, &buffer, sizeof(REGISTER_TYPE));
- sp -= 4 * (GEN_REG_SAVE_COUNT+FLOAT_REG_SAVE_COUNT+SPECIAL_REG_SAVE_COUNT);
+ write_memory (sp - 12, (char *)&buffer, sizeof(REGISTER_TYPE));
+ buffer = read_register (mips_fpu ? FCRCS_REGNUM : ZERO_REGNUM);
+ write_memory (sp - 16, (char *)&buffer, sizeof(REGISTER_TYPE));
+ sp -= 4 * (GEN_REG_SAVE_COUNT
+ + (mips_fpu ? FLOAT_REG_SAVE_COUNT : 0)
+ + SPECIAL_REG_SAVE_COUNT);
write_register (SP_REGNUM, sp);
PROC_LOW_ADDR(proc_desc) = sp - CALL_DUMMY_SIZE + CALL_DUMMY_START_OFFSET;
PROC_HIGH_ADDR(proc_desc) = sp;
void
mips_pop_frame()
-{ register int regnum;
+{
+ register int regnum;
FRAME frame = get_current_frame ();
CORE_ADDR new_sp = frame->frame;
- mips_extra_func_info_t proc_desc = (mips_extra_func_info_t)frame->proc_desc;
+
+ mips_extra_func_info_t proc_desc = frame->proc_desc;
+
+ write_register (PC_REGNUM, FRAME_SAVED_PC(frame));
+ if (proc_desc)
+ {
+ for (regnum = 32; --regnum >= 0; )
+ if (PROC_REG_MASK(proc_desc) & (1 << regnum))
+ write_register (regnum,
+ read_memory_integer (frame->saved_regs->regs[regnum],
+ 4));
+ for (regnum = 32; --regnum >= 0; )
+ if (PROC_FREG_MASK(proc_desc) & (1 << regnum))
+ write_register (regnum + FP0_REGNUM,
+ read_memory_integer (frame->saved_regs->regs[regnum + FP0_REGNUM], 4));
+ }
+ write_register (SP_REGNUM, new_sp);
+ flush_cached_frames ();
+ /* We let mips_init_extra_frame_info figure out the frame pointer */
+ set_current_frame (create_new_frame (0, read_pc ()));
+
if (PROC_DESC_IS_DUMMY(proc_desc))
{
- struct linked_proc_info **ptr = &linked_proc_desc_table;;
- for (; &ptr[0]->info != proc_desc; ptr = &ptr[0]->next )
- if (ptr[0] == NULL) abort();
- *ptr = ptr[0]->next;
- free (ptr[0]);
+ struct linked_proc_info *pi_ptr, *prev_ptr;
+
+ for (pi_ptr = linked_proc_desc_table, prev_ptr = NULL;
+ pi_ptr != NULL;
+ prev_ptr = pi_ptr, pi_ptr = pi_ptr->next)
+ {
+ if (&pi_ptr->info == proc_desc)
+ break;
+ }
+
+ if (pi_ptr == NULL)
+ error ("Can't locate dummy extra frame info\n");
+
+ if (prev_ptr != NULL)
+ prev_ptr->next = pi_ptr->next;
+ else
+ linked_proc_desc_table = pi_ptr->next;
+
+ free (pi_ptr);
+
write_register (HI_REGNUM, read_memory_integer(new_sp - 8, 4));
write_register (LO_REGNUM, read_memory_integer(new_sp - 12, 4));
- write_register (FCRCS_REGNUM, read_memory_integer(new_sp - 16, 4));
+ if (mips_fpu)
+ write_register (FCRCS_REGNUM, read_memory_integer(new_sp - 16, 4));
}
- write_register (PC_REGNUM, FRAME_SAVED_PC(frame));
- if (frame->proc_desc) {
- for (regnum = 32; --regnum >= 0; )
- if (PROC_REG_MASK(proc_desc) & (1 << regnum))
- write_register (regnum,
- read_memory_integer (frame->saved_regs->regs[regnum], 4));
- for (regnum = 32; --regnum >= 0; )
- if (PROC_FREG_MASK(proc_desc) & (1 << regnum))
- write_register (regnum + FP0_REGNUM,
- read_memory_integer (frame->saved_regs->regs[regnum + FP0_REGNUM], 4));
- }
- write_register (SP_REGNUM, new_sp);
- flush_cached_frames ();
- set_current_frame (create_new_frame (new_sp, read_pc ()));
}
-static
-mips_print_register(regnum, all)
+static void
+mips_print_register (regnum, all)
int regnum, all;
{
- unsigned char raw_buffer[8];
+ unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE];
REGISTER_TYPE val;
- read_relative_register_raw_bytes (regnum, raw_buffer);
-
- if (!(regnum & 1) && regnum >= FP0_REGNUM && regnum < FP0_REGNUM+32) {
- read_relative_register_raw_bytes (regnum+1, raw_buffer+4);
- printf_filtered ("(d%d: ", regnum&31);
- val_print (builtin_type_double, raw_buffer, 0,
+ /* Get the data in raw format. */
+ if (read_relative_register_raw_bytes (regnum, raw_buffer))
+ {
+ printf_filtered ("%s: [Invalid]", reg_names[regnum]);
+ return;
+ }
+
+ /* If an even floating pointer register, also print as double. */
+ if (regnum >= FP0_REGNUM && regnum < FP0_REGNUM+32
+ && !((regnum-FP0_REGNUM) & 1)) {
+ char dbuffer[MAX_REGISTER_RAW_SIZE];
+
+ read_relative_register_raw_bytes (regnum, dbuffer);
+ read_relative_register_raw_bytes (regnum+1, dbuffer+4);
+#ifdef REGISTER_CONVERT_TO_TYPE
+ REGISTER_CONVERT_TO_TYPE(regnum, builtin_type_double, dbuffer);
+#endif
+ printf_filtered ("(d%d: ", regnum-FP0_REGNUM);
+ val_print (builtin_type_double, dbuffer, 0,
stdout, 0, 1, 0, Val_pretty_default);
- printf_filtered ("); ", regnum&31);
+ printf_filtered ("); ");
}
fputs_filtered (reg_names[regnum], stdout);
#ifndef NUMERIC_REG_NAMES
long val;
bcopy (raw_buffer, &val, sizeof (long));
+ SWAP_TARGET_AND_HOST ((char *)&val, sizeof (long));
if (val == 0)
printf_filtered ("0");
else if (all)
}
/* Replacement for generic do_registers_info. */
+void
mips_do_registers_info (regnum, fpregs)
int regnum;
int fpregs;
/* Return number of args passed to a frame. described by FIP.
Can return -1, meaning no way to tell. */
+int
mips_frame_num_args(fip)
FRAME fip;
{
}
else if (len == 8)
{
+#if TARGET_BYTE_ORDER == BIG_ENDIAN
+ exponent = *p;
+#else
exponent = *(p+1);
+#endif
exponent = exponent << 1 >> (32 - DOUBLE_EXP_BITS - 1);
return ((exponent == -1) || (! exponent && *p * *(p+1)));
}
else return 1;
}
+\f
+/* To skip prologues, I use this predicate. Returns either PC
+ itself if the code at PC does not look like a function prologue;
+ otherwise returns an address that (if we're lucky) follows
+ the prologue. */
-/* To skip prologues, I use this predicate. Returns either PC
- itself if the code at PC does not look like a function prologue,
- PC+4 if it does (our caller does not need anything more fancy). */
-
-CORE_ADDR mips_skip_prologue(pc)
+CORE_ADDR
+mips_skip_prologue(pc)
CORE_ADDR pc;
{
struct symbol *f;
struct block *b;
unsigned long inst;
+ int offset;
+ int seen_sp_adjust = 0;
+
+ /* Skip the typical prologue instructions. These are the stack adjustment
+ instruction and the instructions that save registers on the stack
+ or in the gcc frame. */
+ for (offset = 0; offset < 100; offset += 4) {
+ inst = read_memory_integer(pc + offset, 4);
+ if ((inst & 0xffff0000) == 0x27bd0000) /* addiu $sp,$sp,offset */
+ seen_sp_adjust = 1;
+ else if ((inst & 0xFFE00000) == 0xAFA00000 && (inst & 0x001F0000))
+ continue; /* sw reg,n($sp) */
+ /* reg != $zero */
+ else if ((inst & 0xFFE00000) == 0xE7A00000) /* swc1 freg,n($sp) */
+ continue;
+ else if ((inst & 0xF3E00000) == 0xA3C00000 && (inst & 0x001F0000))
+ /* sx reg,n($s8) */
+ continue; /* reg != $zero */
+ else if (inst == 0x03A0F021) /* move $s8,$sp */
+ continue;
+ else if ((inst & 0xFF9F07FF) == 0x00800021) /* move reg,$a0-$a3 */
+ continue;
+ else
+ break;
+ }
+ return pc + offset;
- /* For -g modules and most functions anyways the
- first instruction adjusts the stack. */
- inst = read_memory_integer(pc, 4);
- if ((inst & 0xffff0000) == 0x27bd0000)
- return pc + 4;
+/* FIXME schauer. The following code seems no longer necessary if we
+ always skip the typical prologue instructions. */
+
+#if 0
+ if (seen_sp_adjust)
+ return pc + offset;
/* Well, it looks like a frameless. Let's make sure.
Note that we are not called on the current PC,
b = block_for_pc(pc);
if (!b) return pc;
- f = lookup_symbol(".gdbinfo.", b, LABEL_NAMESPACE, 0, NULL);
+ f = lookup_symbol(MIPS_EFI_SYMBOL_NAME, b, LABEL_NAMESPACE, 0, NULL);
if (!f) return pc;
/* Ideally, I would like to use the adjusted info
from mips_frame_info(), but for all practical
Actually, it would not hurt to skip the storing
of arguments on the stack as well. */
- if (((struct mips_extra_func_info *)f->value.value)->framesize)
+ if (((mips_extra_func_info_t)SYMBOL_VALUE(f))->pdr.frameoffset)
return pc + 4;
return pc;
+#endif
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+ extract and copy its value into `valbuf'. */
+void
+mips_extract_return_value (valtype, regbuf, valbuf)
+ struct type *valtype;
+ char regbuf[REGISTER_BYTES];
+ char *valbuf;
+{
+ int regnum;
+
+ regnum = TYPE_CODE (valtype) == TYPE_CODE_FLT && mips_fpu ? FP0_REGNUM : 2;
+
+ memcpy (valbuf, regbuf + REGISTER_BYTE (regnum), TYPE_LENGTH (valtype));
+#ifdef REGISTER_CONVERT_TO_TYPE
+ REGISTER_CONVERT_TO_TYPE(regnum, valtype, valbuf);
+#endif
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+ write it's value into the appropriate register. */
+void
+mips_store_return_value (valtype, valbuf)
+ struct type *valtype;
+ char *valbuf;
+{
+ int regnum;
+ char raw_buffer[MAX_REGISTER_RAW_SIZE];
+
+ regnum = TYPE_CODE (valtype) == TYPE_CODE_FLT && mips_fpu ? FP0_REGNUM : 2;
+ memcpy(raw_buffer, valbuf, TYPE_LENGTH (valtype));
+
+#ifdef REGISTER_CONVERT_FROM_TYPE
+ REGISTER_CONVERT_FROM_TYPE(regnum, valtype, raw_buffer);
+#endif
+
+ write_register_bytes(REGISTER_BYTE (regnum), raw_buffer, TYPE_LENGTH (valtype));
+}
+
+/* Let the user turn off floating point and set the fence post for
+ heuristic_proc_start. */
+
+void
+_initialize_mips_tdep ()
+{
+ add_show_from_set
+ (add_set_cmd ("mipsfpu", class_support, var_boolean,
+ (char *) &mips_fpu,
+ "Set use of floating point coprocessor.\n\
+Turn off to avoid using floating point instructions when calling functions\n\
+or dealing with return values.", &setlist),
+ &showlist);
+
+ add_show_from_set
+ (add_set_cmd ("heuristic-fence-post", class_support, var_uinteger,
+ (char *) &heuristic_fence_post,
+ "Set the distance searched for the start of a function.\n\
+Set number of bytes to be searched backward to find the beginning of a\n\
+function without symbols.", &setlist),
+ &showlist);
}