615 lines
22 KiB
C
615 lines
22 KiB
C
/* Parameters for target execution on an RS6000, for GDB, the GNU debugger.
|
||
Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994
|
||
Free Software Foundation, Inc.
|
||
Contributed by IBM Corporation.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
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. */
|
||
|
||
/* Minimum possible text address in AIX */
|
||
|
||
#define TEXT_SEGMENT_BASE 0x10000000
|
||
|
||
/* Load segment of a given pc value. */
|
||
|
||
#define PC_LOAD_SEGMENT(PC) pc_load_segment_name(PC)
|
||
|
||
/* AIX cc seems to get this right. */
|
||
|
||
#define BELIEVE_PCC_PROMOTION 1
|
||
|
||
/* return true if a given `pc' value is in `call dummy' function. */
|
||
/* FIXME: This just checks for the end of the stack, which is broken
|
||
for things like stepping through gcc nested function stubs. */
|
||
#define PC_IN_CALL_DUMMY(STOP_PC, STOP_SP, STOP_FRAME_ADDR) \
|
||
(STOP_SP < STOP_PC && STOP_PC < STACK_END_ADDR)
|
||
|
||
#if 0
|
||
extern unsigned int text_start, data_start;
|
||
extern char *corefile;
|
||
#endif
|
||
extern int inferior_pid;
|
||
|
||
/* We are missing register descriptions in the system header files. Sigh! */
|
||
|
||
struct regs {
|
||
int gregs [32]; /* general purpose registers */
|
||
int pc; /* program conter */
|
||
int ps; /* processor status, or machine state */
|
||
};
|
||
|
||
struct fp_status {
|
||
double fpregs [32]; /* floating GP registers */
|
||
};
|
||
|
||
|
||
/* To be used by skip_prologue. */
|
||
|
||
struct rs6000_framedata {
|
||
int offset; /* # of bytes in gpr's and fpr's are saved */
|
||
int saved_gpr; /* smallest # of saved gpr */
|
||
int saved_fpr; /* smallest # of saved fpr */
|
||
int alloca_reg; /* alloca register number (frame ptr) */
|
||
char frameless; /* true if frameless functions. */
|
||
char nosavedpc; /* true if pc not saved. */
|
||
int gpr_offset; /* offset of saved gprs */
|
||
int fpr_offset; /* offset of saved fprs */
|
||
int lr_offset; /* offset of saved lr */
|
||
int cr_offset; /* offset of saved cr */
|
||
};
|
||
|
||
/* Define the byte order of the machine. */
|
||
|
||
#define TARGET_BYTE_ORDER BIG_ENDIAN
|
||
|
||
/* AIX's assembler doesn't grok dollar signs in identifiers.
|
||
So we use dots instead. This item must be coordinated with G++. */
|
||
#undef CPLUS_MARKER
|
||
#define CPLUS_MARKER '.'
|
||
|
||
/* Offset from address of function to start of its code.
|
||
Zero on most machines. */
|
||
|
||
#define FUNCTION_START_OFFSET 0
|
||
|
||
/* Advance PC across any function entry prologue instructions
|
||
to reach some "real" code. */
|
||
|
||
#define SKIP_PROLOGUE(pc) \
|
||
do { \
|
||
struct rs6000_framedata _frame; \
|
||
pc = skip_prologue (pc, &_frame); \
|
||
} while (0)
|
||
|
||
extern CORE_ADDR skip_prologue PARAMS((CORE_ADDR, struct rs6000_framedata *));
|
||
|
||
|
||
/* If PC is in some function-call trampoline code, return the PC
|
||
where the function itself actually starts. If not, return NULL. */
|
||
|
||
#define SKIP_TRAMPOLINE_CODE(pc) skip_trampoline_code (pc)
|
||
|
||
/* Number of trap signals we need to skip over, once the inferior process
|
||
starts running. */
|
||
|
||
#define START_INFERIOR_TRAPS_EXPECTED 2
|
||
|
||
/* AIX has a couple of strange returns from wait(). */
|
||
|
||
#define CHILD_SPECIAL_WAITSTATUS(ourstatus, hoststatus) ( \
|
||
/* "stop after load" status. */ \
|
||
(hoststatus) == 0x57c ? (ourstatus)->kind = TARGET_WAITKIND_LOADED, 1 : \
|
||
\
|
||
/* signal 0. I have no idea why wait(2) returns with this status word. */ \
|
||
/* It looks harmless. */ \
|
||
(hoststatus) == 0x7f ? (ourstatus)->kind = TARGET_WAITKIND_SPURIOUS, 1 : \
|
||
\
|
||
/* A normal waitstatus. Let the usual macros deal with it. */ \
|
||
0)
|
||
|
||
/* In xcoff, we cannot process line numbers when we see them. This is
|
||
mainly because we don't know the boundaries of the include files. So,
|
||
we postpone that, and then enter and sort(?) the whole line table at
|
||
once, when we are closing the current symbol table in end_symtab(). */
|
||
|
||
#define PROCESS_LINENUMBER_HOOK() aix_process_linenos ()
|
||
|
||
/* Immediately after a function call, return the saved pc.
|
||
Can't go through the frames for this because on some machines
|
||
the new frame is not set up until the new function executes
|
||
some instructions. */
|
||
|
||
#define SAVED_PC_AFTER_CALL(frame) read_register (LR_REGNUM)
|
||
|
||
/* Address of end of stack space. */
|
||
|
||
#define STACK_END_ADDR 0x2ff80000
|
||
|
||
/* Stack grows downward. */
|
||
|
||
#define INNER_THAN <
|
||
|
||
#if 0
|
||
/* No, we shouldn't use this. push_arguments() should leave stack in a
|
||
proper alignment! */
|
||
/* Stack has strict alignment. */
|
||
|
||
#define STACK_ALIGN(ADDR) (((ADDR)+7)&-8)
|
||
#endif
|
||
|
||
/* This is how argumets pushed onto stack or passed in registers. */
|
||
|
||
#define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \
|
||
sp = push_arguments(nargs, args, sp, struct_return, struct_addr)
|
||
|
||
/* Sequence of bytes for breakpoint instruction. */
|
||
|
||
#define BIG_BREAKPOINT { 0x7d, 0x82, 0x10, 0x08 }
|
||
#define LITTLE_BREAKPOINT { 0x08, 0x10, 0x82, 0x7d }
|
||
|
||
#if TARGET_BYTE_ORDER == BIG_ENDIAN
|
||
#define BREAKPOINT BIG_BREAKPOINT
|
||
|
||
#else
|
||
#if TARGET_BYTE_ORDER == LITTLE_ENDIAN
|
||
#define BREAKPOINT LITTLE_BREAKPOINT
|
||
#endif
|
||
#endif
|
||
|
||
/* Amount PC must be decremented by after a breakpoint.
|
||
This is often the number of bytes in BREAKPOINT
|
||
but not always. */
|
||
|
||
#define DECR_PC_AFTER_BREAK 0
|
||
|
||
/* Nonzero if instruction at PC is a return instruction. */
|
||
/* Allow any of the return instructions, including a trapv and a return
|
||
from interrupt. */
|
||
|
||
#define ABOUT_TO_RETURN(pc) \
|
||
((read_memory_integer (pc, 4) & 0xfe8007ff) == 0x4e800020)
|
||
|
||
/* Say how long (ordinary) registers are. This is a piece of bogosity
|
||
used in push_word and a few other places; REGISTER_RAW_SIZE is the
|
||
real way to know how big a register is. */
|
||
|
||
#define REGISTER_SIZE 4
|
||
|
||
/* Number of machine registers */
|
||
|
||
#define NUM_REGS 71
|
||
|
||
/* Initializer for an array of names of registers.
|
||
There should be NUM_REGS strings in this initializer. */
|
||
|
||
#define REGISTER_NAMES \
|
||
{"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
|
||
"r8", "r9", "r10","r11","r12","r13","r14","r15", \
|
||
"r16","r17","r18","r19","r20","r21","r22","r23", \
|
||
"r24","r25","r26","r27","r28","r29","r30","r31", \
|
||
"f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
|
||
"f8", "f9", "f10","f11","f12","f13","f14","f15", \
|
||
"f16","f17","f18","f19","f20","f21","f22","f23", \
|
||
"f24","f25","f26","f27","f28","f29","f30","f31", \
|
||
"pc", "ps", "cnd", "lr", "cnt", "xer", "mq" }
|
||
|
||
/* Register numbers of various important registers.
|
||
Note that some of these values are "real" register numbers,
|
||
and correspond to the general registers of the machine,
|
||
and some are "phony" register numbers which are too large
|
||
to be actual register numbers as far as the user is concerned
|
||
but do serve to get the desired values when passed to read_register. */
|
||
|
||
#define FP_REGNUM 1 /* Contains address of executing stack frame */
|
||
#define SP_REGNUM 1 /* Contains address of top of stack */
|
||
#define TOC_REGNUM 2 /* TOC register */
|
||
#define FP0_REGNUM 32 /* Floating point register 0 */
|
||
#define GP0_REGNUM 0 /* GPR register 0 */
|
||
#define FP0_REGNUM 32 /* FPR (Floating point) register 0 */
|
||
#define FPLAST_REGNUM 63 /* Last floating point register */
|
||
|
||
/* Special purpose registers... */
|
||
/* P.S. keep these in the same order as in /usr/mstsave.h `mstsave' structure, for
|
||
easier processing */
|
||
|
||
#define PC_REGNUM 64 /* Program counter (instruction address %iar) */
|
||
#define PS_REGNUM 65 /* Processor (or machine) status (%msr) */
|
||
#define CR_REGNUM 66 /* Condition register */
|
||
#define LR_REGNUM 67 /* Link register */
|
||
#define CTR_REGNUM 68 /* Count register */
|
||
#define XER_REGNUM 69 /* Fixed point exception registers */
|
||
#define MQ_REGNUM 70 /* Multiply/quotient register */
|
||
|
||
#define FIRST_SP_REGNUM 64 /* first special register number */
|
||
#define LAST_SP_REGNUM 70 /* last special register number */
|
||
|
||
/* Total amount of space needed to store our copies of the machine's
|
||
register state, the array `registers'.
|
||
|
||
32 4-byte gpr's
|
||
32 8-byte fpr's
|
||
7 4-byte special purpose registers,
|
||
|
||
total 416 bytes. Keep some extra space for now, in case to add more. */
|
||
|
||
#define REGISTER_BYTES 420
|
||
|
||
|
||
/* Index within `registers' of the first byte of the space for
|
||
register N. */
|
||
|
||
#define REGISTER_BYTE(N) \
|
||
( \
|
||
((N) > FPLAST_REGNUM) ? ((((N) - FPLAST_REGNUM -1) * 4) + 384)\
|
||
:((N) >= FP0_REGNUM) ? ((((N) - FP0_REGNUM) * 8) + 128) \
|
||
:((N) * 4) )
|
||
|
||
/* Number of bytes of storage in the actual machine representation
|
||
for register N. */
|
||
/* Note that the unsigned cast here forces the result of the
|
||
subtractiion to very high positive values if N < FP0_REGNUM */
|
||
|
||
#define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
|
||
|
||
/* Number of bytes of storage in the program's representation
|
||
for register N. On the RS6000, all regs are 4 bytes
|
||
except the floating point regs which are 8-byte doubles. */
|
||
|
||
#define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
|
||
|
||
/* Largest value REGISTER_RAW_SIZE can have. */
|
||
|
||
#define MAX_REGISTER_RAW_SIZE 8
|
||
|
||
/* Largest value REGISTER_VIRTUAL_SIZE can have. */
|
||
|
||
#define MAX_REGISTER_VIRTUAL_SIZE 8
|
||
|
||
/* convert a dbx stab register number (from `r' declaration) to a gdb REGNUM */
|
||
|
||
#define STAB_REG_TO_REGNUM(value) (value)
|
||
|
||
/* Nonzero if register N requires conversion
|
||
from raw format to virtual format.
|
||
The register format for rs6000 floating point registers is always
|
||
double, we need a conversion if the memory format is float. */
|
||
|
||
#define REGISTER_CONVERTIBLE(N) ((N) >= FP0_REGNUM && (N) <= FPLAST_REGNUM)
|
||
|
||
/* Convert data from raw format for register REGNUM in buffer FROM
|
||
to virtual format with type TYPE in buffer TO. */
|
||
|
||
#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,TYPE,FROM,TO) \
|
||
{ \
|
||
if (TYPE_LENGTH (TYPE) != REGISTER_RAW_SIZE (REGNUM)) \
|
||
{ \
|
||
double val = extract_floating ((FROM), REGISTER_RAW_SIZE (REGNUM)); \
|
||
store_floating ((TO), TYPE_LENGTH (TYPE), val); \
|
||
} \
|
||
else \
|
||
memcpy ((TO), (FROM), REGISTER_RAW_SIZE (REGNUM)); \
|
||
}
|
||
|
||
/* Convert data from virtual format with type TYPE in buffer FROM
|
||
to raw format for register REGNUM in buffer TO. */
|
||
|
||
#define REGISTER_CONVERT_TO_RAW(TYPE,REGNUM,FROM,TO) \
|
||
{ \
|
||
if (TYPE_LENGTH (TYPE) != REGISTER_RAW_SIZE (REGNUM)) \
|
||
{ \
|
||
double val = extract_floating ((FROM), TYPE_LENGTH (TYPE)); \
|
||
store_floating ((TO), REGISTER_RAW_SIZE (REGNUM), val); \
|
||
} \
|
||
else \
|
||
memcpy ((TO), (FROM), REGISTER_RAW_SIZE (REGNUM)); \
|
||
}
|
||
|
||
/* Return the GDB type object for the "standard" data type
|
||
of data in register N. */
|
||
|
||
#define REGISTER_VIRTUAL_TYPE(N) \
|
||
(((unsigned)(N) - FP0_REGNUM) < 32 ? builtin_type_double : builtin_type_int)
|
||
|
||
/* Store the address of the place in which to copy the structure the
|
||
subroutine will return. This is called from call_function. */
|
||
/* in RS6000, struct return addresses are passed as an extra parameter in r3.
|
||
In function return, callee is not responsible of returning this address back.
|
||
Since gdb needs to find it, we will store in a designated variable
|
||
`rs6000_struct_return_address'. */
|
||
|
||
extern CORE_ADDR rs6000_struct_return_address;
|
||
|
||
#define STORE_STRUCT_RETURN(ADDR, SP) \
|
||
{ write_register (3, (ADDR)); \
|
||
rs6000_struct_return_address = (ADDR); }
|
||
|
||
/* Extract from an array REGBUF containing the (raw) register state
|
||
a function return value of type TYPE, and copy that, in virtual format,
|
||
into VALBUF. */
|
||
|
||
/* #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
|
||
memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE)) */
|
||
|
||
#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
|
||
extract_return_value(TYPE,REGBUF,VALBUF)
|
||
|
||
/* Write into appropriate registers a function return value
|
||
of type TYPE, given in virtual format. */
|
||
|
||
#define STORE_RETURN_VALUE(TYPE,VALBUF) \
|
||
{ \
|
||
if (TYPE_CODE (TYPE) == TYPE_CODE_FLT) \
|
||
\
|
||
/* Floating point values are returned starting from FPR1 and up. \
|
||
Say a double_double_double type could be returned in \
|
||
FPR1/FPR2/FPR3 triple. */ \
|
||
\
|
||
write_register_bytes (REGISTER_BYTE (FP0_REGNUM+1), (VALBUF), \
|
||
TYPE_LENGTH (TYPE)); \
|
||
else \
|
||
/* Everything else is returned in GPR3 and up. */ \
|
||
write_register_bytes (REGISTER_BYTE (GP0_REGNUM+3), (VALBUF), \
|
||
TYPE_LENGTH (TYPE)); \
|
||
}
|
||
|
||
|
||
/* Extract from an array REGBUF containing the (raw) register state
|
||
the address in which a function should return its structure value,
|
||
as a CORE_ADDR (or an expression that can be used as one). */
|
||
|
||
#define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) rs6000_struct_return_address
|
||
|
||
/* Describe the pointer in each stack frame to the previous stack frame
|
||
(its caller). */
|
||
|
||
/* FRAME_CHAIN takes a frame's nominal address
|
||
and produces the frame's chain-pointer. */
|
||
|
||
/* In the case of the RS6000, the frame's nominal address
|
||
is the address of a 4-byte word containing the calling frame's address. */
|
||
|
||
#define FRAME_CHAIN(thisframe) rs6000_frame_chain (thisframe)
|
||
#ifdef __STDC__
|
||
struct frame_info;
|
||
#endif
|
||
CORE_ADDR rs6000_frame_chain PARAMS ((struct frame_info *));
|
||
|
||
/* Define other aspects of the stack frame. */
|
||
|
||
/* A macro that tells us whether the function invocation represented
|
||
by FI does not have a frame on the stack associated with it. If it
|
||
does not, FRAMELESS is set to 1, else 0. */
|
||
|
||
#define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
|
||
FRAMELESS = frameless_function_invocation (FI)
|
||
|
||
extern int frameless_function_invocation PARAMS((struct frame_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. */
|
||
/* Also, it is a good idea to cache information about frame's saved registers
|
||
in the frame structure to speed things up. See tm-m88k.h. FIXME. */
|
||
|
||
#define EXTRA_FRAME_INFO \
|
||
CORE_ADDR initial_sp; /* initial stack pointer. */ \
|
||
struct frame_saved_regs *cache_fsr; /* saved registers */
|
||
|
||
#define INIT_FRAME_PC_FIRST(fromleaf, prev) \
|
||
prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (prev->next) : \
|
||
prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ());
|
||
#define INIT_FRAME_PC(fromleaf, prev) /* nothing */
|
||
#define INIT_EXTRA_FRAME_INFO(fromleaf, fi) \
|
||
fi->initial_sp = 0; \
|
||
fi->cache_fsr = 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;
|
||
|
||
/* If the kernel has to deliver a signal, it pushes a sigcontext
|
||
structure on the stack and then calls the signal handler, passing
|
||
the address of the sigcontext in an argument register. Usually
|
||
the signal handler doesn't save this register, so we have to
|
||
access the sigcontext structure via an offset from the signal handler
|
||
frame.
|
||
The following constants were determined by experimentation on AIX 3.2. */
|
||
#define SIG_FRAME_PC_OFFSET 96
|
||
#define SIG_FRAME_FP_OFFSET 284
|
||
|
||
/* Return saved PC from a frame */
|
||
#define FRAME_SAVED_PC(FRAME) frame_saved_pc (FRAME)
|
||
|
||
extern unsigned long frame_saved_pc PARAMS ((struct frame_info *));
|
||
|
||
#define FRAME_ARGS_ADDRESS(FI) \
|
||
(((struct frame_info*)(FI))->initial_sp ? \
|
||
((struct frame_info*)(FI))->initial_sp : \
|
||
frame_initial_stack_address (FI))
|
||
|
||
#define FRAME_LOCALS_ADDRESS(FI) FRAME_ARGS_ADDRESS(FI)
|
||
|
||
|
||
/* Set VAL to the number of args passed to frame described by FI.
|
||
Can set VAL to -1, meaning no way to tell. */
|
||
|
||
/* We can't tell how many args there are
|
||
now that the C compiler delays popping them. */
|
||
|
||
#define FRAME_NUM_ARGS(val,fi) (val = -1)
|
||
|
||
/* Return number of bytes at start of arglist that are not really args. */
|
||
|
||
#define FRAME_ARGS_SKIP 8 /* Not sure on this. FIXMEmgo */
|
||
|
||
/* Put here the code to store, into a struct frame_saved_regs,
|
||
the addresses of the saved registers of frame described by FRAME_INFO.
|
||
This includes special registers such as pc and fp saved in special
|
||
ways in the stack frame. sp is even more special:
|
||
the address we return for it IS the sp for the next frame. */
|
||
/* In the following implementation for RS6000, we did *not* save sp. I am
|
||
not sure if it will be needed. The following macro takes care of gpr's
|
||
and fpr's only. */
|
||
|
||
#define FRAME_FIND_SAVED_REGS(FRAME_INFO, FRAME_SAVED_REGS) \
|
||
{ \
|
||
int ii; \
|
||
CORE_ADDR frame_addr, func_start; \
|
||
struct rs6000_framedata fdata; \
|
||
\
|
||
/* find the start of the function and collect info about its frame. */ \
|
||
\
|
||
func_start = get_pc_function_start ((FRAME_INFO)->pc) + FUNCTION_START_OFFSET; \
|
||
(void) skip_prologue (func_start, &fdata); \
|
||
memset (&(FRAME_SAVED_REGS), '\0', sizeof (FRAME_SAVED_REGS)); \
|
||
\
|
||
/* 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 (fdata.saved_fpr == 0 && fdata.saved_gpr == 0 && \
|
||
fdata.lr_offset == 0 && fdata.cr_offset == 0) { \
|
||
frame_addr = 0; \
|
||
\
|
||
} else if ((FRAME_INFO)->prev && (FRAME_INFO)->prev->frame) { \
|
||
frame_addr = (FRAME_INFO)->prev->frame; \
|
||
\
|
||
} else { \
|
||
frame_addr = read_memory_integer ((FRAME_INFO)->frame, 4); \
|
||
} \
|
||
\
|
||
/* if != -1, fdata.saved_fpr is the smallest number of saved_fpr. All \
|
||
fpr's from saved_fpr to f31 are saved. */ \
|
||
if (fdata.saved_fpr >= 0) { \
|
||
int fpr_offset = frame_addr + fdata.fpr_offset; \
|
||
for (ii = fdata.saved_fpr; ii < 32; ii++) { \
|
||
(FRAME_SAVED_REGS).regs [FP0_REGNUM + ii] = fpr_offset; \
|
||
fpr_offset += 8; \
|
||
} \
|
||
} \
|
||
\
|
||
/* if != -1, fdata.saved_gpr is the smallest number of saved_gpr. All \
|
||
gpr's from saved_gpr to r31 are saved. */ \
|
||
if (fdata.saved_gpr >= 0) { \
|
||
int gpr_offset = frame_addr + fdata.gpr_offset; \
|
||
for (ii = fdata.saved_gpr; ii < 32; ii++) { \
|
||
(FRAME_SAVED_REGS).regs [ii] = gpr_offset; \
|
||
gpr_offset += 4; \
|
||
} \
|
||
} \
|
||
\
|
||
/* If != 0, fdata.cr_offset is the offset from the frame that holds \
|
||
the CR */ \
|
||
if (fdata.cr_offset != 0) { \
|
||
(FRAME_SAVED_REGS).regs [CR_REGNUM] = frame_addr + fdata.cr_offset; \
|
||
} \
|
||
\
|
||
/* If != 0, fdata.cr_offset is the offset from the frame that holds \
|
||
the LR */ \
|
||
if (fdata.lr_offset != 0) { \
|
||
(FRAME_SAVED_REGS).regs [LR_REGNUM] = frame_addr + fdata.lr_offset; \
|
||
} \
|
||
}
|
||
|
||
|
||
/* Things needed for making the inferior call functions. */
|
||
|
||
/* Push an empty stack frame, to record the current PC, etc. */
|
||
/* Change these names into rs6k_{push, pop}_frame(). FIXMEmgo. */
|
||
|
||
#define PUSH_DUMMY_FRAME push_dummy_frame ()
|
||
|
||
/* Discard from the stack the innermost frame,
|
||
restoring all saved registers. */
|
||
|
||
#define POP_FRAME pop_frame ()
|
||
|
||
/* This sequence of words is the instructions:
|
||
|
||
mflr r0 // 0x7c0802a6
|
||
// save fpr's
|
||
stfd r?, num(r1) // 0xd8010000 there should be 32 of this??
|
||
// save gpr's
|
||
stm r0, num(r1) // 0xbc010000
|
||
stu r1, num(r1) // 0x94210000
|
||
|
||
// the function we want to branch might be in a different load
|
||
// segment. reset the toc register. Note that the actual toc address
|
||
// will be fix by fix_call_dummy () along with function address.
|
||
|
||
st r2, 0x14(r1) // 0x90410014 save toc register
|
||
liu r2, 0x1234 // 0x3c401234 reset a new toc value 0x12345678
|
||
oril r2, r2,0x5678 // 0x60425678
|
||
|
||
// load absolute address 0x12345678 to r0
|
||
liu r0, 0x1234 // 0x3c001234
|
||
oril r0, r0,0x5678 // 0x60005678
|
||
mtctr r0 // 0x7c0903a6 ctr <- r0
|
||
bctrl // 0x4e800421 jump subroutine 0x12345678 (%ctr)
|
||
cror 0xf, 0xf, 0xf // 0x4def7b82
|
||
brpt // 0x7d821008, breakpoint
|
||
cror 0xf, 0xf, 0xf // 0x4def7b82 (for 8 byte alignment)
|
||
|
||
|
||
We actually start executing by saving the toc register first, since the pushing
|
||
of the registers is done by PUSH_DUMMY_FRAME. If this were real code,
|
||
the arguments for the function called by the `bctrl' would be pushed
|
||
between the `stu' and the `bctrl', and we could allow it to execute through.
|
||
But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is done,
|
||
and we cannot allow to push the registers again.
|
||
*/
|
||
|
||
#define CALL_DUMMY {0x7c0802a6, 0xd8010000, 0xbc010000, 0x94210000, \
|
||
0x90410014, 0x3c401234, 0x60425678, \
|
||
0x3c001234, 0x60005678, 0x7c0903a6, 0x4e800421, \
|
||
0x4def7b82, 0x7d821008, 0x4def7b82 }
|
||
|
||
|
||
/* keep this as multiple of 8 (%sp requires 8 byte alignment) */
|
||
#define CALL_DUMMY_LENGTH 56
|
||
|
||
#define CALL_DUMMY_START_OFFSET 16
|
||
|
||
/* Insert the specified number of args and function address
|
||
into a call sequence of the above form stored at DUMMYNAME. */
|
||
|
||
#define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, using_gcc) \
|
||
fix_call_dummy(dummyname, pc, fun, nargs, type)
|
||
|
||
/* Usually a function pointer's representation is simply the address of
|
||
the function. On the RS/6000 however, a function pointer is represented
|
||
by a pointer to a TOC entry. This TOC entry contains three words,
|
||
the first word is the address of the function, the second word is the
|
||
TOC pointer (r2), and the third word is the static chain value.
|
||
Throughout GDB it is currently assumed that a function pointer contains
|
||
the address of the function, which is not easy to fix.
|
||
In addition, the conversion of a function address to a function
|
||
pointer would require allocation of a TOC entry in the inferior's
|
||
memory space, with all its drawbacks.
|
||
To be able to call C++ virtual methods in the inferior (which are called
|
||
via function pointers), find_function_addr uses this macro to
|
||
get the function address from a function pointer. */
|
||
#define CONVERT_FROM_FUNC_PTR_ADDR(ADDR) read_memory_integer (ADDR, 4)
|
||
|
||
/* Flag for machine-specific stuff in shared files. FIXME */
|
||
#define IBM6000_TARGET
|
||
|
||
/* RS6000/AIX does not support PT_STEP. Has to be simulated. */
|
||
|
||
#define NO_SINGLE_STEP
|