/* Target-dependent code for GDB, the GNU debugger.
- Copyright (C) 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997
+ Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "symtab.h"
#include "target.h"
+#include "gdbcore.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "xcoffsolib.h"
-#include <sys/param.h>
-#include <sys/dir.h>
-#include <sys/user.h>
-#include <signal.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
+extern int errno;
-#include <sys/ptrace.h>
-#include <sys/reg.h>
+/* Breakpoint shadows for the single step instructions will be kept here. */
-#include <a.out.h>
-#include <sys/file.h>
-#include <sys/stat.h>
-#include <sys/core.h>
+static struct sstep_breaks {
+ /* Address, or 0 if this is not in use. */
+ CORE_ADDR address;
+ /* Shadow contents. */
+ char data[4];
+} stepBreaks[2];
-extern int errno;
-extern int attach_flag;
+/* Hook for determining the TOC address when calling functions in the
+ inferior under AIX. The initialization code in rs6000-nat.c sets
+ this hook to point to find_toc_address. */
-/* Nonzero if we just simulated a single step break. */
-int one_stepped;
+CORE_ADDR (*find_toc_address_hook) PARAMS ((CORE_ADDR)) = NULL;
+/* Static function prototypes */
-/* Breakpoint shadows for the single step instructions will be kept here. */
+static CORE_ADDR branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc,
+ CORE_ADDR safety));
-static struct sstep_breaks {
- int address;
- int data;
-} stepBreaks[2];
+static void frame_get_saved_regs PARAMS ((struct frame_info *fi,
+ struct rs6000_framedata *fdatap));
+static void pop_dummy_frame PARAMS ((void));
-/*
- * Calculate the destination of a branch/jump. Return -1 if not a branch.
- */
-static int
+static CORE_ADDR frame_initial_stack_address PARAMS ((struct frame_info *));
+
+/* Fill in fi->saved_regs */
+
+struct frame_extra_info
+{
+ /* Functions calling alloca() change the value of the stack
+ pointer. We need to use initial stack pointer (which is saved in
+ r31 by gcc) in such cases. If a compiler emits traceback table,
+ then we should use the alloca register specified in traceback
+ table. FIXME. */
+ CORE_ADDR initial_sp; /* initial stack pointer. */ \
+};
+
+void
+rs6000_init_extra_frame_info (fromleaf, fi)
+ int fromleaf;
+ struct frame_info *fi;
+{
+ fi->extra_info = (struct frame_extra_info*)
+ frame_obstack_alloc (sizeof (struct frame_extra_info));
+ fi->extra_info->initial_sp = 0;
+ if (fi->next != (CORE_ADDR) 0
+ && fi->pc < TEXT_SEGMENT_BASE)
+ /* We're in get_prev_frame_info */
+ /* and this is a special signal frame. */
+ /* (fi->pc will be some low address in the kernel, */
+ /* to which the signal handler returns). */
+ fi->signal_handler_caller = 1;
+}
+
+
+void
+rs6000_frame_init_saved_regs (fi)
+ struct frame_info *fi;
+{
+ frame_get_saved_regs (fi, NULL);
+}
+
+CORE_ADDR
+rs6000_frame_args_address (fi)
+ struct frame_info *fi;
+{
+ if (fi->extra_info->initial_sp != 0)
+ return fi->extra_info->initial_sp;
+ else
+ return frame_initial_stack_address (fi);
+}
+
+
+/* Calculate the destination of a branch/jump. Return -1 if not a branch. */
+
+static CORE_ADDR
branch_dest (opcode, instr, pc, safety)
- int opcode, instr, pc, safety;
+ int opcode;
+ int instr;
+ CORE_ADDR pc;
+ CORE_ADDR safety;
{
- register long offset;
- unsigned dest;
+ CORE_ADDR dest;
int immediate;
int absolute;
int ext_op;
switch (opcode) {
case 18 :
- immediate = ((instr & ~3) << 6) >> 6; /* br unconditionl */
+ immediate = ((instr & ~3) << 6) >> 6; /* br unconditional */
+ if (absolute)
+ dest = immediate;
+ else
+ dest = pc + immediate;
+ break;
case 16 :
- if (opcode != 18) /* br conditional */
- immediate = ((instr & ~3) << 16) >> 16;
+ immediate = ((instr & ~3) << 16) >> 16; /* br conditional */
if (absolute)
dest = immediate;
else
ext_op = (instr>>1) & 0x3ff;
if (ext_op == 16) /* br conditional register */
- dest = read_register (LR_REGNUM) & ~3;
+ {
+ dest = read_register (LR_REGNUM) & ~3;
+
+ /* If we are about to return from a signal handler, dest is
+ something like 0x3c90. The current frame is a signal handler
+ caller frame, upon completion of the sigreturn system call
+ execution will return to the saved PC in the frame. */
+ if (dest < TEXT_SEGMENT_BASE)
+ {
+ struct frame_info *fi;
+
+ fi = get_current_frame ();
+ if (fi != NULL)
+ dest = read_memory_integer (fi->frame + SIG_FRAME_PC_OFFSET,
+ 4);
+ }
+ }
else if (ext_op == 528) /* br cond to count reg */
- dest = read_register (CTR_REGNUM) & ~3;
-
+ {
+ dest = read_register (CTR_REGNUM) & ~3;
+
+ /* If we are about to execute a system call, dest is something
+ like 0x22fc or 0x3b00. Upon completion the system call
+ will return to the address in the link register. */
+ if (dest < TEXT_SEGMENT_BASE)
+ dest = read_register (LR_REGNUM) & ~3;
+ }
else return -1;
break;
}
+/* Sequence of bytes for breakpoint instruction. */
+
+#define BIG_BREAKPOINT { 0x7d, 0x82, 0x10, 0x08 }
+#define LITTLE_BREAKPOINT { 0x08, 0x10, 0x82, 0x7d }
+
+unsigned char *
+rs6000_breakpoint_from_pc (bp_addr, bp_size)
+ CORE_ADDR *bp_addr;
+ int *bp_size;
+{
+ static unsigned char big_breakpoint[] = BIG_BREAKPOINT;
+ static unsigned char little_breakpoint[] = LITTLE_BREAKPOINT;
+ *bp_size = 4;
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ return big_breakpoint;
+ else
+ return little_breakpoint;
+}
+
/* AIX does not support PT_STEP. Simulate it. */
-int
-single_step (signal)
-int signal;
+void
+rs6000_software_single_step (signal, insert_breakpoints_p)
+ enum target_signal signal;
+ int insert_breakpoints_p;
{
#define INSNLEN(OPCODE) 4
- static char breakp[] = BREAKPOINT;
- int ii, insn, ret, loc;
- int breaks[2], opcode;
+ static char le_breakp[] = LITTLE_BREAKPOINT;
+ static char be_breakp[] = BIG_BREAKPOINT;
+ char *breakp = TARGET_BYTE_ORDER == BIG_ENDIAN ? be_breakp : le_breakp;
+ int ii, insn;
+ CORE_ADDR loc;
+ CORE_ADDR breaks[2];
+ int opcode;
+
+ if (insert_breakpoints_p) {
- if (!one_stepped) {
- extern CORE_ADDR text_start;
loc = read_pc ();
- ret = read_memory (loc, &insn, sizeof (int));
- if (ret)
- printf ("Error in single_step()!!\n");
+ insn = read_memory_integer (loc, 4);
breaks[0] = loc + INSNLEN(insn);
opcode = insn >> 26;
if (breaks[1] == breaks[0])
breaks[1] = -1;
- stepBreaks[1].address = -1;
+ stepBreaks[1].address = 0;
for (ii=0; ii < 2; ++ii) {
if ( breaks[ii] == -1)
continue;
- read_memory (breaks[ii], &(stepBreaks[ii].data), sizeof(int));
+ read_memory (breaks[ii], stepBreaks[ii].data, 4);
- ret = write_memory (breaks[ii], breakp, sizeof(int));
+ write_memory (breaks[ii], breakp, 4);
stepBreaks[ii].address = breaks[ii];
}
- one_stepped = 1;
- ptrace (PT_CONTINUE, inferior_pid, 1, signal, 0);
- }
- else {
+ } else {
/* remove step breakpoints. */
for (ii=0; ii < 2; ++ii)
- if (stepBreaks[ii].address != -1)
+ if (stepBreaks[ii].address != 0)
write_memory
- (stepBreaks[ii].address, &(stepBreaks[ii].data), sizeof(int));
+ (stepBreaks[ii].address, stepBreaks[ii].data, 4);
- one_stepped = 0;
}
- errno = 0;
- return 1;
+ errno = 0; /* FIXME, don't ignore errors! */
+ /* What errors? {read,write}_memory call error(). */
}
-/* return pc value after skipping a function prologue. */
-
-skip_prologue (pc)
-int pc;
-{
- unsigned int tmp;
- unsigned int op;
-
- if (target_read_memory (pc, (char *)&op, sizeof (op)))
- return pc; /* Can't access it -- assume no prologue. */
- SWAP_TARGET_AND_HOST (&op, sizeof (op));
-
- /* Assume that subsequent fetches can fail with low probability. */
-
- if (op == 0x7c0802a6) { /* mflr r0 */
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
- pc += 4;
- op = read_memory_integer (pc, 4);
+/* return pc value after skipping a function prologue and also return
+ information about a function frame.
- /* At this point, make sure this is not a trampoline function
- (a function that simply calls another functions, and nothing else).
- If the next is not a nop, this branch was part of the function
- prologue. */
+ in struct rs6000_framedata fdata:
+ - frameless is TRUE, if function does not have a frame.
+ - nosavedpc is TRUE, if function does not save %pc value in its frame.
+ - offset is the initial size of this stack frame --- the amount by
+ which we decrement the sp to allocate the frame.
+ - saved_gpr is the number of the first saved gpr.
+ - saved_fpr is the number of the first saved fpr.
+ - alloca_reg is the number of the register used for alloca() handling.
+ Otherwise -1.
+ - gpr_offset is the offset of the first saved gpr from the previous frame.
+ - fpr_offset is the offset of the first saved fpr from the previous frame.
+ - lr_offset is the offset of the saved lr
+ - cr_offset is the offset of the saved cr
+*/
- if (op == 0x4def7b82 || /* crorc 15, 15, 15 */
- op == 0x0)
- return pc - 4; /* don't skip over this branch */
- }
+#define SIGNED_SHORT(x) \
+ ((sizeof (short) == 2) \
+ ? ((int)(short)(x)) \
+ : ((int)((((x) & 0xffff) ^ 0x8000) - 0x8000)))
- if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
+#define GET_SRC_REG(x) (((x) >> 21) & 0x1f)
- while (((tmp = op >> 16) == 0x9001) || /* st r0, NUM(r1) */
- (tmp == 0x9421) || /* stu r1, NUM(r1) */
- (op == 0x93e1fffc)) /* st r31,-4(r1) */
- {
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */
- pc += 4; /* l r30, ... */
- op = read_memory_integer (pc, 4);
- }
+CORE_ADDR
+skip_prologue (pc, fdata)
+ CORE_ADDR pc;
+ struct rs6000_framedata *fdata;
+{
+ CORE_ADDR orig_pc = pc;
+ char buf[4];
+ unsigned long op;
+ long offset = 0;
+ int lr_reg = 0;
+ int cr_reg = 0;
+ int reg;
+ int framep = 0;
+ int minimal_toc_loaded = 0;
+ static struct rs6000_framedata zero_frame;
+
+ *fdata = zero_frame;
+ fdata->saved_gpr = -1;
+ fdata->saved_fpr = -1;
+ fdata->alloca_reg = -1;
+ fdata->frameless = 1;
+ fdata->nosavedpc = 1;
+
+ if (target_read_memory (pc, buf, 4))
+ return pc; /* Can't access it -- assume no prologue. */
- /* store parameters into stack */
- while(
- (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
- (op & 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
- (op & 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
- (op & 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
+ /* Assume that subsequent fetches can fail with low probability. */
+ pc -= 4;
+ for (;;)
{
- pc += 4; /* store fpr double */
+ pc += 4;
op = read_memory_integer (pc, 4);
- }
- if (op == 0x603f0000) { /* oril r31, r1, 0x0 */
- pc += 4; /* this happens if r31 is used as */
- op = read_memory_integer (pc, 4); /* frame ptr. (gcc does that) */
+ if ((op & 0xfc1fffff) == 0x7c0802a6) { /* mflr Rx */
+ lr_reg = (op & 0x03e00000) | 0x90010000;
+ continue;
+
+ } else if ((op & 0xfc1fffff) == 0x7c000026) { /* mfcr Rx */
+ cr_reg = (op & 0x03e00000) | 0x90010000;
+ continue;
+
+ } else if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
+ reg = GET_SRC_REG (op);
+ if (fdata->saved_fpr == -1 || fdata->saved_fpr > reg) {
+ fdata->saved_fpr = reg;
+ fdata->fpr_offset = SIGNED_SHORT (op) + offset;
+ }
+ continue;
+
+ } else if (((op & 0xfc1f0000) == 0xbc010000) || /* stm Rx, NUM(r1) */
+ ((op & 0xfc1f0000) == 0x90010000 && /* st rx,NUM(r1),
+ rx >= r13 */
+ (op & 0x03e00000) >= 0x01a00000)) {
+
+ reg = GET_SRC_REG (op);
+ if (fdata->saved_gpr == -1 || fdata->saved_gpr > reg) {
+ fdata->saved_gpr = reg;
+ fdata->gpr_offset = SIGNED_SHORT (op) + offset;
+ }
+ continue;
+
+ } else if ((op & 0xffff0000) == 0x3c000000) { /* addis 0,0,NUM, used
+ for >= 32k frames */
+ fdata->offset = (op & 0x0000ffff) << 16;
+ fdata->frameless = 0;
+ continue;
+
+ } else if ((op & 0xffff0000) == 0x60000000) { /* ori 0,0,NUM, 2nd ha
+ lf of >= 32k frames */
+ fdata->offset |= (op & 0x0000ffff);
+ fdata->frameless = 0;
+ continue;
+
+ } else if ((op & 0xffff0000) == lr_reg) { /* st Rx,NUM(r1)
+ where Rx == lr */
+ fdata->lr_offset = SIGNED_SHORT (op) + offset;
+ fdata->nosavedpc = 0;
+ lr_reg = 0;
+ continue;
+
+ } else if ((op & 0xffff0000) == cr_reg) { /* st Rx,NUM(r1)
+ where Rx == cr */
+ fdata->cr_offset = SIGNED_SHORT (op) + offset;
+ cr_reg = 0;
+ continue;
+
+ } else if (op == 0x48000005) { /* bl .+4 used in
+ -mrelocatable */
+ continue;
+
+ } else if (op == 0x48000004) { /* b .+4 (xlc) */
+ break;
- tmp = 0;
- while ((op >> 16) == (0x907f + tmp)) { /* st r3, NUM(r31) */
- pc += 4; /* st r4, NUM(r31), ... */
- op = read_memory_integer (pc, 4);
- tmp += 0x20;
+ } else if (((op & 0xffff0000) == 0x801e0000 || /* lwz 0,NUM(r30), used
+ in V.4 -mrelocatable */
+ op == 0x7fc0f214) && /* add r30,r0,r30, used
+ in V.4 -mrelocatable */
+ lr_reg == 0x901e0000) {
+ continue;
+
+ } else if ((op & 0xffff0000) == 0x3fc00000 || /* addis 30,0,foo@ha, used
+ in V.4 -mminimal-toc */
+ (op & 0xffff0000) == 0x3bde0000) { /* addi 30,30,foo@l */
+ continue;
+
+ } else if ((op & 0xfc000000) == 0x48000000) { /* bl foo,
+ to save fprs??? */
+
+ fdata->frameless = 0;
+ /* Don't skip over the subroutine call if it is not within the first
+ three instructions of the prologue. */
+ if ((pc - orig_pc) > 8)
+ break;
+
+ op = read_memory_integer (pc+4, 4);
+
+ /* At this point, make sure this is not a trampoline function
+ (a function that simply calls another functions, and nothing else).
+ If the next is not a nop, this branch was part of the function
+ prologue. */
+
+ if (op == 0x4def7b82 || op == 0) /* crorc 15, 15, 15 */
+ break; /* don't skip over
+ this branch */
+ continue;
+
+ /* update stack pointer */
+ } else if ((op & 0xffff0000) == 0x94210000) { /* stu r1,NUM(r1) */
+ fdata->frameless = 0;
+ fdata->offset = SIGNED_SHORT (op);
+ offset = fdata->offset;
+ continue;
+
+ } else if (op == 0x7c21016e) { /* stwux 1,1,0 */
+ fdata->frameless = 0;
+ offset = fdata->offset;
+ continue;
+
+ /* Load up minimal toc pointer */
+ } else if ((op >> 22) == 0x20f
+ && ! minimal_toc_loaded) { /* l r31,... or l r30,... */
+ minimal_toc_loaded = 1;
+ continue;
+
+ /* store parameters in stack */
+ } else if ((op & 0xfc1f0000) == 0x90010000 || /* st rx,NUM(r1) */
+ (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
+ (op & 0xfc1f0000) == 0xfc010000) { /* frsp, fp?,NUM(r1) */
+ continue;
+
+ /* store parameters in stack via frame pointer */
+ } else if (framep &&
+ ((op & 0xfc1f0000) == 0x901f0000 || /* st rx,NUM(r1) */
+ (op & 0xfc1f0000) == 0xd81f0000 || /* stfd Rx,NUM(r1) */
+ (op & 0xfc1f0000) == 0xfc1f0000)) { /* frsp, fp?,NUM(r1) */
+ continue;
+
+ /* Set up frame pointer */
+ } else if (op == 0x603f0000 /* oril r31, r1, 0x0 */
+ || op == 0x7c3f0b78) { /* mr r31, r1 */
+ fdata->frameless = 0;
+ framep = 1;
+ fdata->alloca_reg = 31;
+ continue;
+
+ /* Another way to set up the frame pointer. */
+ } else if ((op & 0xfc1fffff) == 0x38010000) { /* addi rX, r1, 0x0 */
+ fdata->frameless = 0;
+ framep = 1;
+ fdata->alloca_reg = (op & ~0x38010000) >> 21;
+ continue;
+
+ } else {
+ break;
+ }
}
- }
+
#if 0
/* I have problems with skipping over __main() that I need to address
* sometime. Previously, I used to use misc_function_vector which
function as well. */
tmp = find_pc_misc_function (pc);
- if (tmp >= 0 && !strcmp (misc_function_vector [tmp].name, "main"))
+ if (tmp >= 0 && STREQ (misc_function_vector [tmp].name, "main"))
return pc + 8;
}
}
#endif /* 0 */
+ fdata->offset = - fdata->offset;
return pc;
}
-/* text start and end addresses in virtual memory. */
-
-CORE_ADDR text_start;
-CORE_ADDR text_end;
-
-
/*************************************************************************
Support for creating pushind a dummy frame into the stack, and popping
frames, etc.
/* push a dummy frame into stack, save all register. Currently we are saving
only gpr's and fpr's, which is not good enough! FIXMEmgo */
+void
push_dummy_frame ()
{
- int sp, pc; /* stack pointer and link register */
+ /* stack pointer. */
+ CORE_ADDR sp;
+ /* Same thing, target byte order. */
+ char sp_targ[4];
+
+ /* link register. */
+ CORE_ADDR pc;
+ /* Same thing, target byte order. */
+ char pc_targ[4];
+
+ /* Needed to figure out where to save the dummy link area.
+ FIXME: There should be an easier way to do this, no? tiemann 9/9/95. */
+ struct rs6000_framedata fdata;
+
int ii;
- fetch_inferior_registers (-1);
+ target_fetch_registers (-1);
if (dummy_frame_count >= dummy_frame_size) {
dummy_frame_size += DUMMY_FRAME_ADDR_SIZE;
}
sp = read_register(SP_REGNUM);
- pc = read_register(PC_REGNUM);
+ pc = read_register(PC_REGNUM);
+ store_address (pc_targ, 4, pc);
+
+ skip_prologue (get_pc_function_start (pc), &fdata);
dummy_frame_addr [dummy_frame_count++] = sp;
before writing register values into the new frame, decrement and update
%sp first in order to secure your frame. */
+ /* FIXME: We don't check if the stack really has this much space.
+ This is a problem on the ppc simulator (which only grants one page
+ (4096 bytes) by default. */
+
write_register (SP_REGNUM, sp-DUMMY_FRAME_SIZE);
/* gdb relies on the state of current_frame. We'd better update it,
otherwise things like do_registers_info() wouldn't work properly! */
flush_cached_frames ();
- set_current_frame (create_new_frame (sp-DUMMY_FRAME_SIZE, pc));
/* save program counter in link register's space. */
- write_memory (sp+8, &pc, 4);
+ write_memory (sp + (fdata.lr_offset ? fdata.lr_offset : DEFAULT_LR_SAVE),
+ pc_targ, 4);
/* save all floating point and general purpose registers here. */
for (ii=1; ii <= (LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) {
write_memory (sp-384-(ii*4),
- ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4);
+ ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4);
}
/* Save sp or so called back chain right here. */
- write_memory (sp-DUMMY_FRAME_SIZE, &sp, 4);
+ store_address (sp_targ, 4, sp);
+ write_memory (sp-DUMMY_FRAME_SIZE, sp_targ, 4);
sp -= DUMMY_FRAME_SIZE;
/* And finally, this is the back chain. */
- write_memory (sp+8, &pc, 4);
+ write_memory (sp+8, pc_targ, 4);
}
addresses of dummy frames as such. When poping happens and when we
detect that was a dummy frame, we pop it back to its parent by using
dummy frame stack (`dummy_frame_addr' array).
+
+FIXME: This whole concept is broken. You should be able to detect
+a dummy stack frame *on the user's stack itself*. When you do,
+then you know the format of that stack frame -- including its
+saved SP register! There should *not* be a separate stack in the
+GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92
*/
+static void
pop_dummy_frame ()
{
CORE_ADDR sp, pc;
®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4);
read_memory (sp-(DUMMY_FRAME_SIZE-8),
- ®isters [REGISTER_BYTE(PC_REGNUM)], 4);
+ ®isters [REGISTER_BYTE(PC_REGNUM)], 4);
/* when a dummy frame was being pushed, we had to decrement %sp first, in
order to secure astack space. Thus, saved %sp (or %r1) value, is not the
one we should restore. Change it with the one we need. */
- *(int*)®isters [REGISTER_BYTE(FP_REGNUM)] = sp;
+ memcpy (®isters [REGISTER_BYTE(FP_REGNUM)], (char *) &sp, sizeof (int));
/* Now we can restore all registers. */
- store_inferior_registers (-1);
+ target_store_registers (-1);
pc = read_pc ();
flush_cached_frames ();
- set_current_frame (create_new_frame (sp, pc));
}
/* pop the innermost frame, go back to the caller. */
+void
pop_frame ()
{
- int pc, lr, sp, prev_sp; /* %pc, %lr, %sp */
- struct aix_framedata fdata;
- FRAME fr = get_current_frame ();
+ CORE_ADDR pc, lr, sp, prev_sp; /* %pc, %lr, %sp */
+ struct rs6000_framedata fdata;
+ struct frame_info *frame = get_current_frame ();
int addr, ii;
pc = read_pc ();
- sp = FRAME_FP (fr);
+ sp = FRAME_FP (frame);
- if (stop_stack_dummy && dummy_frame_count) {
- pop_dummy_frame ();
- return;
- }
+ if (stop_stack_dummy)
+ {
+#ifdef USE_GENERIC_DUMMY_FRAMES
+ generic_pop_dummy_frame ();
+ flush_cached_frames ();
+ return;
+#else
+ if (dummy_frame_count)
+ pop_dummy_frame ();
+ return;
+#endif
+ }
+
+ /* Make sure that all registers are valid. */
+ read_register_bytes (0, NULL, REGISTER_BYTES);
/* figure out previous %pc value. If the function is frameless, it is
still in the link register, otherwise walk the frames and retrieve the
saved %pc value in the previous frame. */
- addr = get_pc_function_start (fr->pc) + FUNCTION_START_OFFSET;
- function_frame_info (addr, &fdata);
+ addr = get_pc_function_start (frame->pc);
+ (void) skip_prologue (addr, &fdata);
- read_memory (sp, &prev_sp, 4);
if (fdata.frameless)
+ prev_sp = sp;
+ else
+ prev_sp = read_memory_integer (sp, 4);
+ if (fdata.lr_offset == 0)
lr = read_register (LR_REGNUM);
else
- read_memory (prev_sp+8, &lr, 4);
+ lr = read_memory_integer (prev_sp + fdata.lr_offset, 4);
/* reset %pc value. */
write_register (PC_REGNUM, lr);
/* reset register values if any was saved earlier. */
- addr = prev_sp - fdata.offset;
if (fdata.saved_gpr != -1)
- for (ii=fdata.saved_gpr; ii <= 31; ++ii) {
- read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4);
- addr += sizeof (int);
+ {
+ addr = prev_sp + fdata.gpr_offset;
+ for (ii = fdata.saved_gpr; ii <= 31; ++ii) {
+ read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4);
+ addr += 4;
+ }
}
if (fdata.saved_fpr != -1)
- for (ii=fdata.saved_fpr; ii <= 31; ++ii) {
- read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8);
- addr += 8;
- }
+ {
+ addr = prev_sp + fdata.fpr_offset;
+ for (ii = fdata.saved_fpr; ii <= 31; ++ii) {
+ read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8);
+ addr += 8;
+ }
+ }
write_register (SP_REGNUM, prev_sp);
- store_inferior_registers (-1);
+ target_store_registers (-1);
flush_cached_frames ();
- set_current_frame (create_new_frame (prev_sp, lr));
}
-
/* fixup the call sequence of a dummy function, with the real function address.
its argumets will be passed by gdb. */
-fix_call_dummy(dummyname, pc, fun, nargs, type)
- char *dummyname;
- int pc;
- int fun;
- int nargs; /* not used */
- int type; /* not used */
-
+void
+rs6000_fix_call_dummy (dummyname, pc, fun, nargs, args, type, gcc_p)
+ char *dummyname;
+ CORE_ADDR pc;
+ CORE_ADDR fun;
+ int nargs;
+ value_ptr *args;
+ struct type *type;
+ int gcc_p;
{
#define TOC_ADDR_OFFSET 20
#define TARGET_ADDR_OFFSET 28
int ii;
- unsigned long target_addr;
- unsigned long tocvalue;
+ CORE_ADDR target_addr;
- target_addr = fun;
- tocvalue = find_toc_address (target_addr);
+ if (find_toc_address_hook != NULL)
+ {
+ CORE_ADDR tocvalue;
- ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET);
- ii = (ii & 0xffff0000) | (tocvalue >> 16);
- *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii;
+ tocvalue = (*find_toc_address_hook) (fun);
+ ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET);
+ ii = (ii & 0xffff0000) | (tocvalue >> 16);
+ *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii;
- ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4);
- ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff);
- *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii;
+ ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4);
+ ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff);
+ *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii;
+ }
+ target_addr = fun;
ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET);
ii = (ii & 0xffff0000) | (target_addr >> 16);
*(int*)((char*)dummyname + TARGET_ADDR_OFFSET) = ii;
*(int*)((char*)dummyname + TARGET_ADDR_OFFSET+4) = ii;
}
-
-
-/* return information about a function frame.
- in struct aix_frameinfo fdata:
- - frameless is TRUE, if function does not save %pc value in its frame.
- - offset is the number of bytes used in the frame to save registers.
- - saved_gpr is the number of the first saved gpr.
- - saved_fpr is the number of the first saved fpr.
- - alloca_reg is the number of the register used for alloca() handling.
- Otherwise -1.
- */
-function_frame_info (pc, fdata)
- int pc;
- struct aix_framedata *fdata;
-{
- unsigned int tmp;
- register unsigned int op;
-
- fdata->offset = 0;
- fdata->saved_gpr = fdata->saved_fpr = fdata->alloca_reg = -1;
-
- op = read_memory_integer (pc, 4);
- if (op == 0x7c0802a6) { /* mflr r0 */
- pc += 4;
- op = read_memory_integer (pc, 4);
- fdata->frameless = 0;
- }
- else /* else, this is a frameless invocation */
- fdata->frameless = 1;
-
-
- if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
- pc += 4;
- op = read_memory_integer (pc, 4);
- /* At this point, make sure this is not a trampoline function
- (a function that simply calls another functions, and nothing else).
- If the next is not a nop, this branch was part of the function
- prologue. */
-
- if (op == 0x4def7b82 || /* crorc 15, 15, 15 */
- op == 0x0)
- return; /* prologue is over */
- }
-
- if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
- pc += 4; /* store floating register double */
- op = read_memory_integer (pc, 4);
- }
-
- if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
- int tmp2;
- fdata->saved_gpr = (op >> 21) & 0x1f;
- tmp2 = op & 0xffff;
- if (tmp2 > 0x7fff)
- tmp2 = 0xffff0000 | tmp2;
-
- if (tmp2 < 0) {
- tmp2 = tmp2 * -1;
- fdata->saved_fpr = (tmp2 - ((32 - fdata->saved_gpr) * 4)) / 8;
- if ( fdata->saved_fpr > 0)
- fdata->saved_fpr = 32 - fdata->saved_fpr;
- else
- fdata->saved_fpr = -1;
- }
- fdata->offset = tmp2;
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- while (((tmp = op >> 16) == 0x9001) || /* st r0, NUM(r1) */
- (tmp == 0x9421) || /* stu r1, NUM(r1) */
- (op == 0x93e1fffc)) /* st r31,-4(r1) */
- {
- /* gcc takes a short cut and uses this instruction to save r31 only. */
-
- if (op == 0x93e1fffc) {
- if (fdata->offset)
-/* fatal ("Unrecognized prolog."); */
- printf ("Unrecognized prolog!\n");
-
- fdata->saved_gpr = 31;
- fdata->offset = 4;
- }
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
-
- while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */
- pc += 4; /* l r30, ... */
- op = read_memory_integer (pc, 4);
- }
-
- /* store parameters into stack */
- while(
- (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
- (op & 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
- (op & 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
- (op & 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
- {
- pc += 4; /* store fpr double */
- op = read_memory_integer (pc, 4);
- }
-
- if (op == 0x603f0000) /* oril r31, r1, 0x0 */
- fdata->alloca_reg = 31;
-}
-
-
-/* Pass the arguments in either registers, or in the stack. In RS6000, the first
- eight words of the argument list (that might be less than eight parameters if
- some parameters occupy more than one word) are passed in r3..r11 registers.
- float and double parameters are passed in fpr's, in addition to that. Rest of
- the parameters if any are passed in user stack. There might be cases in which
- half of the parameter is copied into registers, the other half is pushed into
+/* Pass the arguments in either registers, or in the stack. In RS6000,
+ the first eight words of the argument list (that might be less than
+ eight parameters if some parameters occupy more than one word) are
+ passed in r3..r11 registers. float and double parameters are
+ passed in fpr's, in addition to that. Rest of the parameters if any
+ are passed in user stack. There might be cases in which half of the
+ parameter is copied into registers, the other half is pushed into
stack.
If the function is returning a structure, then the return address is passed
- in r3, then the first 7 words of the parametes can be passed in registers,
+ in r3, then the first 7 words of the parameters can be passed in registers,
starting from r4. */
CORE_ADDR
push_arguments (nargs, args, sp, struct_return, struct_addr)
- int nargs;
- value *args;
- CORE_ADDR sp;
- int struct_return;
- CORE_ADDR struct_addr;
+ int nargs;
+ value_ptr *args;
+ CORE_ADDR sp;
+ int struct_return;
+ CORE_ADDR struct_addr;
{
- int ii, len;
+ int ii;
+ int len = 0;
int argno; /* current argument number */
int argbytes; /* current argument byte */
char tmp_buffer [50];
- value arg;
int f_argno = 0; /* current floating point argno */
- CORE_ADDR saved_sp, pc;
+ value_ptr arg = 0;
+ struct type *type;
+ CORE_ADDR saved_sp;
+
+#ifndef USE_GENERIC_DUMMY_FRAMES
if ( dummy_frame_count <= 0)
- printf ("FATAL ERROR -push_arguments()! frame not found!!\n");
+ printf_unfiltered ("FATAL ERROR -push_arguments()! frame not found!!\n");
+#endif /* GENERIC_DUMMY_FRAMES */
/* The first eight words of ther arguments are passed in registers. Copy
them appropriately.
ii = struct_return ? 1 : 0;
+/*
+effectively indirect call... gcc does...
+
+return_val example( float, int);
+
+eabi:
+ float in fp0, int in r3
+ offset of stack on overflow 8/16
+ for varargs, must go by type.
+power open:
+ float in r3&r4, int in r5
+ offset of stack on overflow different
+both:
+ return in r3 or f0. If no float, must study how gcc emulates floats;
+ pay attention to arg promotion.
+ User may have to cast\args to handle promotion correctly
+ since gdb won't know if prototype supplied or not.
+*/
+
for (argno=0, argbytes=0; argno < nargs && ii<8; ++ii) {
- arg = value_arg_coerce (args[argno]);
- len = TYPE_LENGTH (VALUE_TYPE (arg));
+ arg = args[argno];
+ type = check_typedef (VALUE_TYPE (arg));
+ len = TYPE_LENGTH (type);
- if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FLT) {
+ if (TYPE_CODE (type) == TYPE_CODE_FLT) {
/* floating point arguments are passed in fpr's, as well as gpr's.
There are 13 fpr's reserved for passing parameters. At this point
there is no way we would run out of them. */
if (len > 8)
- printf (
+ printf_unfiltered (
"Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno);
- bcopy (VALUE_CONTENTS (arg),
- ®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], len);
+ memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)],
+ VALUE_CONTENTS (arg),
+ len);
++f_argno;
}
/* Argument takes more than one register. */
while (argbytes < len) {
-
- *(int*)®isters[REGISTER_BYTE(ii+3)] = 0;
- bcopy ( ((char*)VALUE_CONTENTS (arg))+argbytes,
- ®isters[REGISTER_BYTE(ii+3)],
- (len - argbytes) > 4 ? 4 : len - argbytes);
+ memset (®isters[REGISTER_BYTE(ii+3)], 0, sizeof(int));
+ memcpy (®isters[REGISTER_BYTE(ii+3)],
+ ((char*)VALUE_CONTENTS (arg))+argbytes,
+ (len - argbytes) > 4 ? 4 : len - argbytes);
++ii, argbytes += 4;
if (ii >= 8)
--ii;
}
else { /* Argument can fit in one register. No problem. */
- *(int*)®isters[REGISTER_BYTE(ii+3)] = 0;
- bcopy (VALUE_CONTENTS (arg), ®isters[REGISTER_BYTE(ii+3)], len);
+ memset (®isters[REGISTER_BYTE(ii+3)], 0, sizeof(int));
+ memcpy (®isters[REGISTER_BYTE(ii+3)], VALUE_CONTENTS (arg), len);
}
++argno;
}
ran_out_of_registers_for_arguments:
+#ifdef USE_GENERIC_DUMMY_FRAMES
+ saved_sp = read_sp ();
+#else
/* location for 8 parameters are always reserved. */
sp -= 4 * 8;
/* another six words for back chain, TOC register, link register, etc. */
sp -= 24;
-
+#endif /* GENERIC_DUMMY_FRAMES */
/* if there are more arguments, allocate space for them in
the stack, then push them starting from the ninth one. */
if ((argno < nargs) || argbytes) {
int space = 0, jj;
- value val;
if (argbytes) {
space += ((len - argbytes + 3) & -4);
jj = argno;
for (; jj < nargs; ++jj) {
- val = value_arg_coerce (args[jj]);
+ value_ptr val = args[jj];
space += ((TYPE_LENGTH (VALUE_TYPE (val))) + 3) & -4;
}
completely, push the rest of it into stack. */
if (argbytes) {
- write_memory (
- sp+24+(ii*4), ((char*)VALUE_CONTENTS (arg))+argbytes, len - argbytes);
+ write_memory (sp+24+(ii*4),
+ ((char*)VALUE_CONTENTS (arg))+argbytes,
+ len - argbytes);
++argno;
ii += ((len - argbytes + 3) & -4) / 4;
}
/* push the rest of the arguments into stack. */
for (; argno < nargs; ++argno) {
- arg = value_arg_coerce (args[argno]);
- len = TYPE_LENGTH (VALUE_TYPE (arg));
+ arg = args[argno];
+ type = check_typedef (VALUE_TYPE (arg));
+ len = TYPE_LENGTH (type);
/* float types should be passed in fpr's, as well as in the stack. */
- if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FLT && f_argno < 13) {
+ if (TYPE_CODE (type) == TYPE_CODE_FLT && f_argno < 13) {
if (len > 8)
- printf (
+ printf_unfiltered (
"Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno);
- bcopy (VALUE_CONTENTS (arg),
- ®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], len);
+ memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)],
+ VALUE_CONTENTS (arg),
+ len);
++f_argno;
}
- write_memory (sp+24+(ii*4), VALUE_CONTENTS (arg), len);
+ write_memory (sp+24+(ii*4), (char *) VALUE_CONTENTS (arg), len);
ii += ((len + 3) & -4) / 4;
}
}
/* Secure stack areas first, before doing anything else. */
write_register (SP_REGNUM, sp);
+#ifndef USE_GENERIC_DUMMY_FRAMES
+/* we want to copy 24 bytes of target's frame to dummy's frame,
+ then set back chain to point to new frame. */
+
saved_sp = dummy_frame_addr [dummy_frame_count - 1];
read_memory (saved_sp, tmp_buffer, 24);
write_memory (sp, tmp_buffer, 24);
+#endif /* GENERIC_DUMMY_FRAMES */
+
+ /* set back chain properly */
+ store_address (tmp_buffer, 4, saved_sp);
+ write_memory (sp, tmp_buffer, 4);
- write_memory (sp, &saved_sp, 4); /* set back chain properly */
+ target_store_registers (-1);
+ return sp;
+}
+#ifdef ELF_OBJECT_FORMAT
- store_inferior_registers (-1);
+/* Function: ppc_push_return_address (pc, sp)
+ Set up the return address for the inferior function call. */
+
+CORE_ADDR
+ppc_push_return_address (pc, sp)
+ CORE_ADDR pc;
+ CORE_ADDR sp;
+{
+ write_register (LR_REGNUM, CALL_DUMMY_ADDRESS ());
return sp;
}
+#endif
+
/* a given return value in `regbuf' with a type `valtype', extract and copy its
value into `valbuf' */
+void
extract_return_value (valtype, regbuf, valbuf)
- struct type *valtype;
- char regbuf[REGISTER_BYTES];
- char *valbuf;
+ struct type *valtype;
+ char regbuf[REGISTER_BYTES];
+ char *valbuf;
{
+ int offset = 0;
if (TYPE_CODE (valtype) == TYPE_CODE_FLT) {
necessary. */
if (TYPE_LENGTH (valtype) > 4) /* this is a double */
- bcopy (®buf[REGISTER_BYTE (FP0_REGNUM + 1)], valbuf,
- TYPE_LENGTH (valtype));
+ memcpy (valbuf,
+ ®buf[REGISTER_BYTE (FP0_REGNUM + 1)],
+ TYPE_LENGTH (valtype));
else { /* float */
- bcopy (®buf[REGISTER_BYTE (FP0_REGNUM + 1)], &dd, 8);
+ memcpy (&dd, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], 8);
ff = (float)dd;
- bcopy (&ff, valbuf, sizeof(float));
+ memcpy (valbuf, &ff, sizeof(float));
}
}
- else
+ else {
/* return value is copied starting from r3. */
- bcopy (®buf[REGISTER_BYTE (3)], valbuf, TYPE_LENGTH (valtype));
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN
+ && TYPE_LENGTH (valtype) < REGISTER_RAW_SIZE (3))
+ offset = REGISTER_RAW_SIZE (3) - TYPE_LENGTH (valtype);
+
+ memcpy (valbuf,
+ regbuf + REGISTER_BYTE (3) + offset,
+ TYPE_LENGTH (valtype));
+ }
}
-/* keep keep structure return address in this variable. */
+/* keep structure return address in this variable.
+ FIXME: This is a horrid kludge which should not be allowed to continue
+ living. This only allows a single nested call to a structure-returning
+ function. Come on, guys! -- gnu@cygnus.com, Aug 92 */
CORE_ADDR rs6000_struct_return_address;
-/* Throw away this debugging code. FIXMEmgo. */
-print_frame(fram)
-int fram;
-{
- int ii, val;
- for (ii=0; ii<40; ++ii) {
- if ((ii % 4) == 0)
- printf ("\n");
- val = read_memory_integer (fram + ii * 4, 4);
- printf ("0x%08x\t", val);
- }
- printf ("\n");
-}
-
-
-
/* Indirect function calls use a piece of trampoline code to do context
switching, i.e. to set the new TOC table. Skip such code if we are on
its first instruction (as when we have single-stepped to here).
+ Also skip shared library trampoline code (which is different from
+ indirect function call trampolines).
Result is desired PC to step until, or NULL if we are not in
trampoline code. */
+CORE_ADDR
skip_trampoline_code (pc)
-int pc;
+ CORE_ADDR pc;
{
register unsigned int ii, op;
+ CORE_ADDR solib_target_pc;
static unsigned trampoline_code[] = {
0x800b0000, /* l r0,0x0(r11) */
0
};
+ /* If pc is in a shared library trampoline, return its target. */
+ solib_target_pc = find_solib_trampoline_target (pc);
+ if (solib_target_pc)
+ return solib_target_pc;
+
for (ii=0; trampoline_code[ii]; ++ii) {
op = read_memory_integer (pc + (ii*4), 4);
if (op != trampoline_code [ii])
- return NULL;
+ return 0;
}
ii = read_register (11); /* r11 holds destination addr */
pc = read_memory_integer (ii, 4); /* (r11) value */
return pc;
}
+/* Determines whether the function FI has a frame on the stack or not. */
+
+int
+frameless_function_invocation (fi)
+ struct frame_info *fi;
+{
+ CORE_ADDR func_start;
+ struct rs6000_framedata fdata;
+
+ /* Don't even think about framelessness except on the innermost frame
+ or if the function was interrupted by a signal. */
+ if (fi->next != NULL && !fi->next->signal_handler_caller)
+ return 0;
+
+ func_start = get_pc_function_start (fi->pc);
+
+ /* If we failed to find the start of the function, it is a mistake
+ to inspect the instructions. */
+
+ if (!func_start)
+ {
+ /* A frame with a zero PC is usually created by dereferencing a NULL
+ function pointer, normally causing an immediate core dump of the
+ inferior. Mark function as frameless, as the inferior has no chance
+ of setting up a stack frame. */
+ if (fi->pc == 0)
+ return 1;
+ else
+ return 0;
+ }
+
+ (void) skip_prologue (func_start, &fdata);
+ return fdata.frameless;
+}
+
+/* Return the PC saved in a frame */
+
+unsigned long
+frame_saved_pc (fi)
+ struct frame_info *fi;
+{
+ CORE_ADDR func_start;
+ struct rs6000_framedata fdata;
+
+ if (fi->signal_handler_caller)
+ return read_memory_integer (fi->frame + SIG_FRAME_PC_OFFSET, 4);
+
+#ifdef USE_GENERIC_DUMMY_FRAMES
+ if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
+ return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM);
+#endif /* GENERIC_DUMMY_FRAMES */
+
+ func_start = get_pc_function_start (fi->pc);
+
+ /* If we failed to find the start of the function, it is a mistake
+ to inspect the instructions. */
+ if (!func_start)
+ return 0;
+
+ (void) skip_prologue (func_start, &fdata);
+
+ if (fdata.lr_offset == 0 && fi->next != NULL)
+ {
+ if (fi->next->signal_handler_caller)
+ return read_memory_integer (fi->next->frame + SIG_FRAME_LR_OFFSET, 4);
+ else
+ return read_memory_integer (rs6000_frame_chain (fi) + DEFAULT_LR_SAVE,
+ 4);
+ }
+
+ if (fdata.lr_offset == 0)
+ return read_register (LR_REGNUM);
+
+ return read_memory_integer (rs6000_frame_chain (fi) + fdata.lr_offset, 4);
+}
+
+/* If saved registers of frame FI are not known yet, read and cache them.
+ &FDATAP contains rs6000_framedata; TDATAP can be NULL,
+ in which case the framedata are read. */
+
+static void
+frame_get_saved_regs (fi, fdatap)
+ struct frame_info *fi;
+ struct rs6000_framedata *fdatap;
+{
+ int ii;
+ CORE_ADDR frame_addr;
+ struct rs6000_framedata work_fdata;
+
+ if (fi->saved_regs)
+ return;
+
+ if (fdatap == NULL)
+ {
+ fdatap = &work_fdata;
+ (void) skip_prologue (get_pc_function_start (fi->pc), fdatap);
+ }
+
+ frame_saved_regs_zalloc (fi);
+
+ /* If there were any saved registers, figure out parent's stack
+ pointer. */
+ /* The following is true only if the frame doesn't have a call to
+ alloca(), FIXME. */
+
+ if (fdatap->saved_fpr == 0 && fdatap->saved_gpr == 0
+ && fdatap->lr_offset == 0 && fdatap->cr_offset == 0)
+ frame_addr = 0;
+ else if (fi->prev && fi->prev->frame)
+ frame_addr = fi->prev->frame;
+ else
+ frame_addr = read_memory_integer (fi->frame, 4);
+
+ /* if != -1, fdatap->saved_fpr is the smallest number of saved_fpr.
+ All fpr's from saved_fpr to fp31 are saved. */
+
+ if (fdatap->saved_fpr >= 0)
+ {
+ int i;
+ int fpr_offset = frame_addr + fdatap->fpr_offset;
+ for (i = fdatap->saved_fpr; i < 32; i++)
+ {
+ fi->saved_regs [FP0_REGNUM + i] = fpr_offset;
+ fpr_offset += 8;
+ }
+ }
+
+ /* if != -1, fdatap->saved_gpr is the smallest number of saved_gpr.
+ All gpr's from saved_gpr to gpr31 are saved. */
+
+ if (fdatap->saved_gpr >= 0)
+ {
+ int i;
+ int gpr_offset = frame_addr + fdatap->gpr_offset;
+ for (i = fdatap->saved_gpr; i < 32; i++)
+ {
+ fi->saved_regs [i] = gpr_offset;
+ gpr_offset += 4;
+ }
+ }
+
+ /* If != 0, fdatap->cr_offset is the offset from the frame that holds
+ the CR. */
+ if (fdatap->cr_offset != 0)
+ fi->saved_regs [CR_REGNUM] = frame_addr + fdatap->cr_offset;
+
+ /* If != 0, fdatap->lr_offset is the offset from the frame that holds
+ the LR. */
+ if (fdatap->lr_offset != 0)
+ fi->saved_regs [LR_REGNUM] = frame_addr + fdatap->lr_offset;
+}
+
+/* Return the address of a frame. This is the inital %sp value when the frame
+ was first allocated. For functions calling alloca(), it might be saved in
+ an alloca register. */
+
+static CORE_ADDR
+frame_initial_stack_address (fi)
+ struct frame_info *fi;
+{
+ CORE_ADDR tmpaddr;
+ struct rs6000_framedata fdata;
+ struct frame_info *callee_fi;
+
+ /* if the initial stack pointer (frame address) of this frame is known,
+ just return it. */
+
+ if (fi->extra_info->initial_sp)
+ return fi->extra_info->initial_sp;
+
+ /* find out if this function is using an alloca register.. */
+
+ (void) skip_prologue (get_pc_function_start (fi->pc), &fdata);
+
+ /* if saved registers of this frame are not known yet, read and cache them. */
+
+ if (!fi->saved_regs)
+ frame_get_saved_regs (fi, &fdata);
+
+ /* If no alloca register used, then fi->frame is the value of the %sp for
+ this frame, and it is good enough. */
+
+ if (fdata.alloca_reg < 0)
+ {
+ fi->extra_info->initial_sp = fi->frame;
+ return fi->extra_info->initial_sp;
+ }
+
+ /* This function has an alloca register. If this is the top-most frame
+ (with the lowest address), the value in alloca register is good. */
+
+ if (!fi->next)
+ return fi->extra_info->initial_sp = read_register (fdata.alloca_reg);
+
+ /* Otherwise, this is a caller frame. Callee has usually already saved
+ registers, but there are exceptions (such as when the callee
+ has no parameters). Find the address in which caller's alloca
+ register is saved. */
+
+ for (callee_fi = fi->next; callee_fi; callee_fi = callee_fi->next) {
+
+ if (!callee_fi->saved_regs)
+ frame_get_saved_regs (callee_fi, NULL);
+
+ /* this is the address in which alloca register is saved. */
+
+ tmpaddr = callee_fi->saved_regs [fdata.alloca_reg];
+ if (tmpaddr) {
+ fi->extra_info->initial_sp = read_memory_integer (tmpaddr, 4);
+ return fi->extra_info->initial_sp;
+ }
+
+ /* Go look into deeper levels of the frame chain to see if any one of
+ the callees has saved alloca register. */
+ }
+
+ /* If alloca register was not saved, by the callee (or any of its callees)
+ then the value in the register is still good. */
+
+ fi->extra_info->initial_sp = read_register (fdata.alloca_reg);
+ return fi->extra_info->initial_sp;
+}
+
+CORE_ADDR
+rs6000_frame_chain (thisframe)
+ struct frame_info *thisframe;
+{
+ CORE_ADDR fp;
+
+#ifdef USE_GENERIC_DUMMY_FRAMES
+ if (PC_IN_CALL_DUMMY (thisframe->pc, thisframe->frame, thisframe->frame))
+ return thisframe->frame; /* dummy frame same as caller's frame */
+#endif /* GENERIC_DUMMY_FRAMES */
+
+ if (inside_entry_file (thisframe->pc) ||
+ thisframe->pc == entry_point_address ())
+ return 0;
+
+ if (thisframe->signal_handler_caller)
+ fp = read_memory_integer (thisframe->frame + SIG_FRAME_FP_OFFSET, 4);
+ else if (thisframe->next != NULL
+ && thisframe->next->signal_handler_caller
+ && frameless_function_invocation (thisframe))
+ /* A frameless function interrupted by a signal did not change the
+ frame pointer. */
+ fp = FRAME_FP (thisframe);
+ else
+ fp = read_memory_integer ((thisframe)->frame, 4);
+
+#ifdef USE_GENERIC_DUMMY_FRAMES
+ {
+ CORE_ADDR fpp, lr;
+
+ lr = read_register (LR_REGNUM);
+ if (lr == entry_point_address ())
+ if (fp != 0 && (fpp = read_memory_integer (fp, 4)) != 0)
+ if (PC_IN_CALL_DUMMY (lr, fpp, fpp))
+ return fpp;
+ }
+#endif /* GENERIC_DUMMY_FRAMES */
+ return fp;
+}
+\f
+/* Return nonzero if ADDR (a function pointer) is in the data space and
+ is therefore a special function pointer. */
+
+int
+is_magic_function_pointer (addr)
+ CORE_ADDR addr;
+{
+ struct obj_section *s;
+
+ s = find_pc_section (addr);
+ if (s && s->the_bfd_section->flags & SEC_CODE)
+ return 0;
+ else
+ return 1;
+}
+
+#ifdef GDB_TARGET_POWERPC
+int
+gdb_print_insn_powerpc (memaddr, info)
+ bfd_vma memaddr;
+ disassemble_info *info;
+{
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ return print_insn_big_powerpc (memaddr, info);
+ else
+ return print_insn_little_powerpc (memaddr, info);
+}
+#endif
+
+/* Function: get_saved_register
+ Just call the generic_get_saved_register function. */
+
+#ifdef USE_GENERIC_DUMMY_FRAMES
+void
+get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval)
+ char *raw_buffer;
+ int *optimized;
+ CORE_ADDR *addrp;
+ struct frame_info *frame;
+ int regnum;
+ enum lval_type *lval;
+{
+ generic_get_saved_register (raw_buffer, optimized, addrp,
+ frame, regnum, lval);
+}
+#endif
+
+
+void
+_initialize_rs6000_tdep ()
+{
+ /* FIXME, this should not be decided via ifdef. */
+#ifdef GDB_TARGET_POWERPC
+ tm_print_insn = gdb_print_insn_powerpc;
+#else
+ tm_print_insn = print_insn_rs6000;
+#endif
+}