/* 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. */
-
-#include <stdio.h>
+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 <sys/param.h>
-#include <sys/dir.h>
-#include <sys/user.h>
-#include <signal.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-
-#include <sys/ptrace.h>
-#include <sys/reg.h>
-
-#include <a.out.h>
-#include <sys/file.h>
-#include <sys/stat.h>
-#include <sys/core.h>
+#include "gdbcore.h"
+#include "gdbcmd.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "xcoffsolib.h"
extern int errno;
-extern int attach_flag;
-
-/* Nonzero if we just simulated a single step break. */
-int one_stepped;
/* Breakpoint shadows for the single step instructions will be kept here. */
static struct sstep_breaks {
- int address;
- int data;
+ /* Address, or 0 if this is not in use. */
+ CORE_ADDR address;
+ /* Shadow contents. */
+ char data[4];
} stepBreaks[2];
+/* 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. */
-/*
- * Calculate the destination of a branch/jump. Return -1 if not a branch.
- */
-static int
+CORE_ADDR (*find_toc_address_hook) PARAMS ((CORE_ADDR)) = NULL;
+
+/* Static function prototypes */
+
+static CORE_ADDR branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc,
+ CORE_ADDR safety));
+
+static void frame_get_saved_regs PARAMS ((struct frame_info *fi,
+ struct rs6000_framedata *fdatap));
+
+static void pop_dummy_frame PARAMS ((void));
+
+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. */
+/* return pc value after skipping a function prologue and also return
+ information about a function frame.
-skip_prologue (pc)
-int pc;
-{
- unsigned int tmp;
- unsigned int op;
+ 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 (target_read_memory (pc, (char *)&op, sizeof (op)))
+#define SIGNED_SHORT(x) \
+ ((sizeof (short) == 2) \
+ ? ((int)(short)(x)) \
+ : ((int)((((x) & 0xffff) ^ 0x8000) - 0x8000)))
+
+#define GET_SRC_REG(x) (((x) >> 21) & 0x1f)
+
+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. */
- SWAP_TARGET_AND_HOST (&op, sizeof (op));
/* Assume that subsequent fetches can fail with low probability. */
+ pc -= 4;
+ for (;;)
+ {
+ pc += 4;
+ op = read_memory_integer (pc, 4);
- 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 & 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;
- if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
+ } 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
- if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
- pc += 4; /* store floating register double */
- op = read_memory_integer (pc, 4);
- }
-#endif
+/* I have problems with skipping over __main() that I need to address
+ * sometime. Previously, I used to use misc_function_vector which
+ * didn't work as well as I wanted to be. -MGO */
- if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
- 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) */
- {
- pc += 4;
- op = read_memory_integer (pc, 4);
- }
+ /* If the first thing after skipping a prolog is a branch to a function,
+ this might be a call to an initializer in main(), introduced by gcc2.
+ We'd like to skip over it as well. Fortunately, xlc does some extra
+ work before calling a function right after a prologue, thus we can
+ single out such gcc2 behaviour. */
+
- while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */
- pc += 4; /* l r30, ... */
- op = read_memory_integer (pc, 4);
- }
+ if ((op & 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */
+ op = read_memory_integer (pc+4, 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 == 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */
- 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) */
+ /* check and see if we are in main. If so, skip over this initializer
+ function as well. */
- 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;
+ tmp = find_pc_misc_function (pc);
+ 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;
+ target_fetch_registers (-1);
+
if (dummy_frame_count >= dummy_frame_size) {
dummy_frame_size += DUMMY_FRAME_ADDR_SIZE;
if (dummy_frame_addr)
}
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;
/* Be careful! If the stack pointer is not decremented first, then kernel
- thinks he is free to use the sapce underneath it. And kernel actually
+ thinks he is free to use the space underneath it. And kernel actually
uses that area for IPC purposes when executing ptrace(2) calls. So
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 full floating point registers here. They will be from F14..F31
- for know. I am not sure if we need to save everything here! */
+ /* save all floating point and general purpose registers here. */
/* fpr's, f0..f31 */
for (ii = 0; ii < 32; ++ii)
/* so far, 32*2 + 32 words = 384 bytes have been written.
7 extra registers in our register set: pc, ps, cnd, lr, cnt, xer, mq */
- for (ii=1; ii <= (LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) {
+ for (ii=1; ii <= (LAST_UISA_SP_REGNUM-FIRST_UISA_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;
}
/* restore the rest of the registers. */
- for (ii=1; ii <=(LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii)
+ for (ii=1; ii <=(LAST_UISA_SP_REGNUM-FIRST_UISA_SP_REGNUM+1); ++ii)
read_memory (sp-384-(ii*4),
®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 */
- FRAME fr = get_current_frame ();
- int offset = 0;
- int frameless = 0; /* TRUE if function is frameless */
+ CORE_ADDR pc, lr, sp, prev_sp; /* %pc, %lr, %sp */
+ struct rs6000_framedata fdata;
+ struct frame_info *frame = get_current_frame ();
int addr, ii;
- int saved_gpr, saved_fpr; /* # of saved gpr's and fpr's */
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, &frameless, &offset, &saved_gpr, &saved_fpr);
+ addr = get_pc_function_start (frame->pc);
+ (void) skip_prologue (addr, &fdata);
- read_memory (sp, &prev_sp, 4);
- if (frameless)
+ 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 - offset;
- if (saved_gpr != -1)
- for (ii=saved_gpr; ii <= 31; ++ii) {
- read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4);
- addr += sizeof (int);
+ if (fdata.saved_gpr != -1)
+ {
+ 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 (saved_fpr != -1)
- for (ii=saved_fpr; ii <= 31; ++ii) {
- read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8);
- addr += 8;
- }
+ if (fdata.saved_fpr != -1)
+ {
+ 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.
- - 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.
- */
-function_frame_info (pc, frameless, offset, saved_gpr, saved_fpr)
- int pc;
- int *frameless, *offset, *saved_gpr, *saved_fpr;
-{
- unsigned int tmp;
- register unsigned int op;
-
- *offset = 0;
- *saved_gpr = *saved_fpr = -1;
-
- if (!inferior_pid)
- return;
-
- op = read_memory_integer (pc, 4);
- if (op == 0x7c0802a6) { /* mflr r0 */
- pc += 4;
- op = read_memory_integer (pc, 4);
- *frameless = 0;
- }
- else /* else, this is a frameless invocation */
- *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);
- }
-
- 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;
- *saved_gpr = (op >> 21) & 0x1f;
- tmp2 = op & 0xffff;
- if (tmp2 > 0x7fff)
- tmp2 = 0xffff0000 | tmp2;
-
- if (tmp2 < 0) {
- tmp2 = tmp2 * -1;
- *saved_fpr = (tmp2 - ((32 - *saved_gpr) * 4)) / 8;
- if ( *saved_fpr > 0)
- *saved_fpr = 32 - *saved_fpr;
- else
- *saved_fpr = -1;
- }
- *offset = tmp2;
- }
-}
-
-
-/* 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;
}
write_register (SP_REGNUM, sp);
-#if 0
- pc = read_pc ();
- flush_cached_frames ();
- set_current_frame (create_new_frame (sp, pc));
-#endif
-
/* if the last argument copied into the registers didn't fit there
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;
}
}
- else {
-
+ else
/* Secure stack areas first, before doing anything else. */
write_register (SP_REGNUM, sp);
-#if 0
- pc = read_pc ();
- flush_cached_frames ();
- set_current_frame (create_new_frame (sp, pc));
-#endif
- }
+#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
+
+/* Function: ppc_push_return_address (pc, sp)
+ Set up the return address for the inferior function call. */
- store_inferior_registers (-1);
+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 do co context switching,
- i.e. to set the new TOC table. Skip such code if exists. */
+/* 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
+
+
+\f
+/* Handling the various PowerPC/RS6000 variants. */
+
+
+/* The arrays here called register_names_MUMBLE hold names that
+ the rs6000_register_name function returns.
+
+ For each family of PPC variants, I've tried to isolate out the
+ common registers and put them up front, so that as long as you get
+ the general family right, GDB will correctly identify the registers
+ common to that family. The common register sets are:
+
+ For the 60x family: hid0 hid1 iabr dabr pir
+
+ For the 505 and 860 family: eie eid nri
+
+ For the 403 and 403GC: icdbdr esr dear evpr cdbcr tsr tcr pit tbhi
+ tblo srr2 srr3 dbsr dbcr iac1 iac2 dac1 dac2 dccr iccr pbl1
+ pbu1 pbl2 pbu2
+
+ Most of these register groups aren't anything formal. I arrived at
+ them by looking at the registers that occurred in more than one
+ processor. */
+
+/* UISA register names common across all architectures, including POWER. */
+
+#define COMMON_UISA_REG_NAMES \
+ /* 0 */ "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
+ /* 8 */ "r8", "r9", "r10","r11","r12","r13","r14","r15", \
+ /* 16 */ "r16","r17","r18","r19","r20","r21","r22","r23", \
+ /* 24 */ "r24","r25","r26","r27","r28","r29","r30","r31", \
+ /* 32 */ "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
+ /* 40 */ "f8", "f9", "f10","f11","f12","f13","f14","f15", \
+ /* 48 */ "f16","f17","f18","f19","f20","f21","f22","f23", \
+ /* 56 */ "f24","f25","f26","f27","f28","f29","f30","f31", \
+ /* 64 */ "pc", "ps"
+
+/* UISA-level SPR names for PowerPC. */
+#define PPC_UISA_SPR_NAMES \
+ /* 66 */ "cr", "lr", "ctr", "xer", ""
+
+/* Segment register names, for PowerPC. */
+#define PPC_SEGMENT_REG_NAMES \
+ /* 71 */ "sr0", "sr1", "sr2", "sr3", "sr4", "sr5", "sr6", "sr7", \
+ /* 79 */ "sr8", "sr9", "sr10", "sr11", "sr12", "sr13", "sr14", "sr15"
+
+/* OEA SPR names for 32-bit PowerPC implementations.
+ The blank space is for "asr", which is only present on 64-bit
+ implementations. */
+#define PPC_32_OEA_SPR_NAMES \
+ /* 87 */ "pvr", \
+ /* 88 */ "ibat0u", "ibat0l", "ibat1u", "ibat1l", \
+ /* 92 */ "ibat2u", "ibat2l", "ibat3u", "ibat3l", \
+ /* 96 */ "dbat0u", "dbat0l", "dbat1u", "dbat1l", \
+ /* 100 */ "dbat2u", "dbat2l", "dbat3u", "dbat3l", \
+ /* 104 */ "sdr1", "", "dar", "dsisr", "sprg0", "sprg1", "sprg2", "sprg3",\
+ /* 112 */ "srr0", "srr1", "tbl", "tbu", "dec", "dabr", "ear"
+
+/* For the RS6000, we only cover user-level SPR's. */
+char *register_names_rs6000[] =
+{
+ COMMON_UISA_REG_NAMES,
+ /* 66 */ "cnd", "lr", "cnt", "xer", "mq"
+};
+
+/* a UISA-only view of the PowerPC. */
+char *register_names_uisa[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES
+};
+
+char *register_names_403[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "icdbdr", "esr", "dear", "evpr", "cdbcr", "tsr", "tcr", "pit",
+ /* 127 */ "tbhi", "tblo", "srr2", "srr3", "dbsr", "dbcr", "iac1", "iac2",
+ /* 135 */ "dac1", "dac2", "dccr", "iccr", "pbl1", "pbu1", "pbl2", "pbu2"
+};
+
+char *register_names_403GC[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "icdbdr", "esr", "dear", "evpr", "cdbcr", "tsr", "tcr", "pit",
+ /* 127 */ "tbhi", "tblo", "srr2", "srr3", "dbsr", "dbcr", "iac1", "iac2",
+ /* 135 */ "dac1", "dac2", "dccr", "iccr", "pbl1", "pbu1", "pbl2", "pbu2",
+ /* 143 */ "zpr", "pid", "sgr", "dcwr", "tbhu", "tblu"
+};
+
+char *register_names_505[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "eie", "eid", "nri"
+};
+
+char *register_names_860[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "eie", "eid", "nri", "cmpa", "cmpb", "cmpc", "cmpd", "icr",
+ /* 127 */ "der", "counta", "countb", "cmpe", "cmpf", "cmpg", "cmph",
+ /* 134 */ "lctrl1", "lctrl2", "ictrl", "bar", "ic_cst", "ic_adr", "ic_dat",
+ /* 141 */ "dc_cst", "dc_adr", "dc_dat", "dpdr", "dpir", "immr", "mi_ctr",
+ /* 148 */ "mi_ap", "mi_epn", "mi_twc", "mi_rpn", "md_ctr", "m_casid",
+ /* 154 */ "md_ap", "md_epn", "md_twb", "md_twc", "md_rpn", "m_tw",
+ /* 160 */ "mi_dbcam", "mi_dbram0", "mi_dbram1", "md_dbcam", "md_dbram0",
+ /* 165 */ "md_dbram1"
+};
+
+/* Note that the 601 has different register numbers for reading and
+ writing RTCU and RTCL. However, how one reads and writes a
+ register is the stub's problem. */
+char *register_names_601[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "hid0", "hid1", "iabr", "dabr", "pir", "mq", "rtcu",
+ /* 126 */ "rtcl"
+};
+
+char *register_names_602[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "hid0", "hid1", "iabr", "", "", "tcr", "ibr", "esassr", "sebr",
+ /* 128 */ "ser", "sp", "lt"
+};
+
+char *register_names_603[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "hid0", "hid1", "iabr", "", "", "dmiss", "dcmp", "hash1",
+ /* 127 */ "hash2", "imiss", "icmp", "rpa"
+};
+
+char *register_names_604[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "hid0", "hid1", "iabr", "dabr", "pir", "mmcr0", "pmc1", "pmc2",
+ /* 127 */ "sia", "sda"
+};
+
+char *register_names_750[] =
+{
+ COMMON_UISA_REG_NAMES,
+ PPC_UISA_SPR_NAMES,
+ PPC_SEGMENT_REG_NAMES,
+ PPC_32_OEA_SPR_NAMES,
+ /* 119 */ "hid0", "hid1", "iabr", "dabr", "", "ummcr0", "upmc1", "upmc2",
+ /* 127 */ "usia", "ummcr1", "upmc3", "upmc4", "mmcr0", "pmc1", "pmc2",
+ /* 134 */ "sia", "mmcr1", "pmc3", "pmc4", "l2cr", "ictc", "thrm1", "thrm2",
+ /* 142 */ "thrm3"
+};
+
+
+/* Information about a particular processor variant. */
+struct variant
+{
+ /* Name of this variant. */
+ char *name;
+
+ /* English description of the variant. */
+ char *description;
+
+ /* Table of register names; registers[R] is the name of the register
+ number R. */
+ int num_registers;
+ char **registers;
+};
+
+#define num_registers(list) (sizeof (list) / sizeof((list)[0]))
+
+
+/* Information in this table comes from the following web sites:
+ IBM: http://www.chips.ibm.com:80/products/embedded/
+ Motorola: http://www.mot.com/SPS/PowerPC/
+
+ I'm sure I've got some of the variant descriptions not quite right.
+ Please report any inaccuracies you find to GDB's maintainer.
+
+ If you add entries to this table, please be sure to allow the new
+ value as an argument to the --with-cpu flag, in configure.in. */
+
+static struct variant
+variants[] =
+{
+ { "ppc-uisa", "PowerPC UISA - a PPC processor as viewed by user-level code",
+ num_registers (register_names_uisa), register_names_uisa },
+ { "rs6000", "IBM RS6000 (\"POWER\") architecture, user-level view",
+ num_registers (register_names_rs6000), register_names_rs6000 },
+ { "403", "IBM PowerPC 403",
+ num_registers (register_names_403), register_names_403 },
+ { "403GC", "IBM PowerPC 403GC",
+ num_registers (register_names_403GC), register_names_403GC },
+ { "505", "Motorola PowerPC 505",
+ num_registers (register_names_505), register_names_505 },
+ { "860", "Motorola PowerPC 860 or 850",
+ num_registers (register_names_860), register_names_860 },
+ { "601", "Motorola PowerPC 601",
+ num_registers (register_names_601), register_names_601 },
+ { "602", "Motorola PowerPC 602",
+ num_registers (register_names_602), register_names_602 },
+ { "603", "Motorola/IBM PowerPC 603 or 603e",
+ num_registers (register_names_603), register_names_603 },
+ { "604", "Motorola PowerPC 604 or 604e",
+ num_registers (register_names_604), register_names_604 },
+ { "750", "Motorola/IBM PowerPC 750 or 750",
+ num_registers (register_names_750), register_names_750 },
+ { 0, 0, 0, 0 }
+};
+
+
+static struct variant *current_variant;
+
+char *
+rs6000_register_name (int i)
+{
+ if (i < 0 || i >= NUM_REGS)
+ error ("GDB bug: rs6000-tdep.c (rs6000_register_name): strange register number");
+
+ return ((i < current_variant->num_registers)
+ ? current_variant->registers[i]
+ : "");
+}
+
+
+static void
+install_variant (struct variant *v)
+{
+ current_variant = v;
+}
+
+
+/* Look up the variant named NAME in the `variants' table. Return a
+ pointer to the struct variant, or null if we couldn't find it. */
+static struct variant *
+find_variant_by_name (char *name)
+{
+ int i;
+
+ for (i = 0; variants[i].name; i++)
+ if (! strcmp (name, variants[i].name))
+ return &variants[i];
+
+ return 0;
+}
+
+
+/* Install the PPC/RS6000 variant named NAME in the `variants' table.
+ Return zero if we installed it successfully, or a non-zero value if
+ we couldn't do it.
+
+ This might be useful to code outside this file, which doesn't want
+ to depend on the exact indices of the entries in the `variants'
+ table. Just make it non-static if you want that. */
+static int
+install_variant_by_name (char *name)
+{
+ struct variant *v = find_variant_by_name (name);
+
+ if (v)
+ {
+ install_variant (v);
+ return 0;
+ }
+ else
+ return 1;
+}
+
+
+static void
+list_variants ()
+{
+ int i;
+
+ printf_filtered ("GDB knows about the following PowerPC and RS6000 variants:\n");
+
+ for (i = 0; variants[i].name; i++)
+ printf_filtered (" %-8s %s\n",
+ variants[i].name, variants[i].description);
+}
+
+
+static void
+show_current_variant ()
+{
+ printf_filtered ("PowerPC / RS6000 processor variant is set to `%s'.\n",
+ current_variant->name);
+}
+
+
+static void
+set_processor (char *arg, int from_tty)
+{
+ int i;
+
+ if (! arg || arg[0] == '\0')
+ {
+ list_variants ();
+ return;
+ }
+
+ if (install_variant_by_name (arg))
+ {
+ error_begin ();
+ fprintf_filtered (gdb_stderr,
+ "`%s' is not a recognized PowerPC / RS6000 variant name.\n\n", arg);
+ list_variants ();
+ return_to_top_level (RETURN_ERROR);
+ }
+
+ show_current_variant ();
+}
+
+static void
+show_processor (char *arg, int from_tty)
+{
+ show_current_variant ();
+}
+
+
+\f
+/* Initialization code. */
+
+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
+
+ /* I don't think we should use the set/show command arrangement
+ here, because the way that's implemented makes it hard to do the
+ error checking we want in a reasonable way. So we just add them
+ as two separate commands. */
+ add_cmd ("processor", class_support, set_processor,
+ "`set processor NAME' sets the PowerPC/RS6000 variant to NAME.\n\
+If you set this, GDB will know about the special-purpose registers that are\n\
+available on the given variant.\n\
+Type `set processor' alone for a list of recognized variant names.",
+ &setlist);
+ add_cmd ("processor", class_support, show_processor,
+ "Show the variant of the PowerPC or RS6000 processor in use.\n\
+Use `set processor' to change this.",
+ &showlist);
+
+ /* Set the current PPC processor variant. */
+ {
+ int status = 1;
+
+#ifdef TARGET_CPU_DEFAULT
+ status = install_variant_by_name (TARGET_CPU_DEFAULT);
+#endif
+
+ if (status)
+ {
+#ifdef GDB_TARGET_POWERPC
+ install_variant_by_name ("ppc-uisa");
+#else
+ install_variant_by_name ("rs6000");
+#endif
+ }
+ }
+}
projects / thirdparty / binutils-gdb.git / blobdiff