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author | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:34:07 +0000 |
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committer | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:34:07 +0000 |
commit | 071ea11e85eb9d529cc5eb3d35f6247466a21b99 (patch) | |
tree | 5deda65b8d7b04d1f4cbc534c3206d328e1267ec /gdb/m88k-tdep.c | |
parent | 1730ec6b1848f0f32154277f788fb29f88d8475b (diff) | |
download | gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.zip gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.tar.gz gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.tar.bz2 |
Initial creation of sourceware repository
Diffstat (limited to 'gdb/m88k-tdep.c')
-rw-r--r-- | gdb/m88k-tdep.c | 629 |
1 files changed, 0 insertions, 629 deletions
diff --git a/gdb/m88k-tdep.c b/gdb/m88k-tdep.c deleted file mode 100644 index f82cb76..0000000 --- a/gdb/m88k-tdep.c +++ /dev/null @@ -1,629 +0,0 @@ -/* Target-machine dependent code for Motorola 88000 series, for GDB. - Copyright 1988, 1990, 1991, 1994, 1995 Free Software Foundation, Inc. - -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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ - -#include "defs.h" -#include "frame.h" -#include "inferior.h" -#include "value.h" -#include "gdbcore.h" -#include "symtab.h" -#include "setjmp.h" -#include "value.h" - -/* Size of an instruction */ -#define BYTES_PER_88K_INSN 4 - -void frame_find_saved_regs (); - -/* Is this target an m88110? Otherwise assume m88100. This has - relevance for the ways in which we screw with instruction pointers. */ - -int target_is_m88110 = 0; - -/* The m88k kernel aligns all instructions on 4-byte boundaries. The - kernel also uses the least significant two bits for its own hocus - pocus. When gdb receives an address from the kernel, it needs to - preserve those right-most two bits, but gdb also needs to be careful - to realize that those two bits are not really a part of the address - of an instruction. Shrug. */ - -CORE_ADDR -m88k_addr_bits_remove (addr) - CORE_ADDR addr; -{ - return ((addr) & ~3); -} - - -/* Given a GDB frame, determine the address of the calling function's frame. - This will be used to create a new GDB frame struct, and then - INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame. - - For us, the frame address is its stack pointer value, so we look up - the function prologue to determine the caller's sp value, and return it. */ - -CORE_ADDR -frame_chain (thisframe) - struct frame_info *thisframe; -{ - - frame_find_saved_regs (thisframe, (struct frame_saved_regs *) 0); - /* NOTE: this depends on frame_find_saved_regs returning the VALUE, not - the ADDRESS, of SP_REGNUM. It also depends on the cache of - frame_find_saved_regs results. */ - if (thisframe->fsr->regs[SP_REGNUM]) - return thisframe->fsr->regs[SP_REGNUM]; - else - return thisframe->frame; /* Leaf fn -- next frame up has same SP. */ -} - -int -frameless_function_invocation (frame) - struct frame_info *frame; -{ - - frame_find_saved_regs (frame, (struct frame_saved_regs *) 0); - /* NOTE: this depends on frame_find_saved_regs returning the VALUE, not - the ADDRESS, of SP_REGNUM. It also depends on the cache of - frame_find_saved_regs results. */ - if (frame->fsr->regs[SP_REGNUM]) - return 0; /* Frameful -- return addr saved somewhere */ - else - return 1; /* Frameless -- no saved return address */ -} - -void -init_extra_frame_info (fromleaf, frame) - int fromleaf; - struct frame_info *frame; -{ - frame->fsr = 0; /* Not yet allocated */ - frame->args_pointer = 0; /* Unknown */ - frame->locals_pointer = 0; /* Unknown */ -} - -/* Examine an m88k function prologue, recording the addresses at which - registers are saved explicitly by the prologue code, and returning - the address of the first instruction after the prologue (but not - after the instruction at address LIMIT, as explained below). - - LIMIT places an upper bound on addresses of the instructions to be - examined. If the prologue code scan reaches LIMIT, the scan is - aborted and LIMIT is returned. This is used, when examining the - prologue for the current frame, to keep examine_prologue () from - claiming that a given register has been saved when in fact the - instruction that saves it has not yet been executed. LIMIT is used - at other times to stop the scan when we hit code after the true - function prologue (e.g. for the first source line) which might - otherwise be mistaken for function prologue. - - The format of the function prologue matched by this routine is - derived from examination of the source to gcc 1.95, particularly - the routine output_prologue () in config/out-m88k.c. - - subu r31,r31,n # stack pointer update - - (st rn,r31,offset)? # save incoming regs - (st.d rn,r31,offset)? - - (addu r30,r31,n)? # frame pointer update - - (pic sequence)? # PIC code prologue - - (or rn,rm,0)? # Move parameters to other regs -*/ - -/* Macros for extracting fields from instructions. */ - -#define BITMASK(pos, width) (((0x1 << (width)) - 1) << (pos)) -#define EXTRACT_FIELD(val, pos, width) ((val) >> (pos) & BITMASK (0, width)) -#define SUBU_OFFSET(x) ((unsigned)(x & 0xFFFF)) -#define ST_OFFSET(x) ((unsigned)((x) & 0xFFFF)) -#define ST_SRC(x) EXTRACT_FIELD ((x), 21, 5) -#define ADDU_OFFSET(x) ((unsigned)(x & 0xFFFF)) - -/* - * prologue_insn_tbl is a table of instructions which may comprise a - * function prologue. Associated with each table entry (corresponding - * to a single instruction or group of instructions), is an action. - * This action is used by examine_prologue (below) to determine - * the state of certain machine registers and where the stack frame lives. - */ - -enum prologue_insn_action { - PIA_SKIP, /* don't care what the instruction does */ - PIA_NOTE_ST, /* note register stored and where */ - PIA_NOTE_STD, /* note pair of registers stored and where */ - PIA_NOTE_SP_ADJUSTMENT, /* note stack pointer adjustment */ - PIA_NOTE_FP_ASSIGNMENT, /* note frame pointer assignment */ - PIA_NOTE_PROLOGUE_END, /* no more prologue */ -}; - -struct prologue_insns { - unsigned long insn; - unsigned long mask; - enum prologue_insn_action action; -}; - -struct prologue_insns prologue_insn_tbl[] = { - /* Various register move instructions */ - { 0x58000000, 0xf800ffff, PIA_SKIP }, /* or/or.u with immed of 0 */ - { 0xf4005800, 0xfc1fffe0, PIA_SKIP }, /* or rd, r0, rs */ - { 0xf4005800, 0xfc00ffff, PIA_SKIP }, /* or rd, rs, r0 */ - - /* Stack pointer setup: "subu sp, sp, n" where n is a multiple of 8 */ - { 0x67ff0000, 0xffff0007, PIA_NOTE_SP_ADJUSTMENT }, - - /* Frame pointer assignment: "addu r30, r31, n" */ - { 0x63df0000, 0xffff0000, PIA_NOTE_FP_ASSIGNMENT }, - - /* Store to stack instructions; either "st rx, sp, n" or "st.d rx, sp, n" */ - { 0x241f0000, 0xfc1f0000, PIA_NOTE_ST }, /* st rx, sp, n */ - { 0x201f0000, 0xfc1f0000, PIA_NOTE_STD }, /* st.d rs, sp, n */ - - /* Instructions needed for setting up r25 for pic code. */ - { 0x5f200000, 0xffff0000, PIA_SKIP }, /* or.u r25, r0, offset_high */ - { 0xcc000002, 0xffffffff, PIA_SKIP }, /* bsr.n Lab */ - { 0x5b390000, 0xffff0000, PIA_SKIP }, /* or r25, r25, offset_low */ - { 0xf7396001, 0xffffffff, PIA_SKIP }, /* Lab: addu r25, r25, r1 */ - - /* Various branch or jump instructions which have a delay slot -- these - do not form part of the prologue, but the instruction in the delay - slot might be a store instruction which should be noted. */ - { 0xc4000000, 0xe4000000, PIA_NOTE_PROLOGUE_END }, - /* br.n, bsr.n, bb0.n, or bb1.n */ - { 0xec000000, 0xfc000000, PIA_NOTE_PROLOGUE_END }, /* bcnd.n */ - { 0xf400c400, 0xfffff7e0, PIA_NOTE_PROLOGUE_END } /* jmp.n or jsr.n */ - -}; - - -/* Fetch the instruction at ADDR, returning 0 if ADDR is beyond LIM or - is not the address of a valid instruction, the address of the next - instruction beyond ADDR otherwise. *PWORD1 receives the first word - of the instruction. */ - -#define NEXT_PROLOGUE_INSN(addr, lim, pword1) \ - (((addr) < (lim)) ? next_insn (addr, pword1) : 0) - -/* Read the m88k instruction at 'memaddr' and return the address of - the next instruction after that, or 0 if 'memaddr' is not the - address of a valid instruction. The instruction - is stored at 'pword1'. */ - -CORE_ADDR -next_insn (memaddr, pword1) - unsigned long *pword1; - CORE_ADDR memaddr; -{ - *pword1 = read_memory_integer (memaddr, BYTES_PER_88K_INSN); - return memaddr + BYTES_PER_88K_INSN; -} - -/* Read a register from frames called by us (or from the hardware regs). */ - -static int -read_next_frame_reg(frame, regno) - struct frame_info *frame; - int regno; -{ - for (; frame; frame = frame->next) { - if (regno == SP_REGNUM) - return FRAME_FP (frame); - else if (frame->fsr->regs[regno]) - return read_memory_integer(frame->fsr->regs[regno], 4); - } - return read_register(regno); -} - -/* Examine the prologue of a function. `ip' points to the first instruction. - `limit' is the limit of the prologue (e.g. the addr of the first - linenumber, or perhaps the program counter if we're stepping through). - `frame_sp' is the stack pointer value in use in this frame. - `fsr' is a pointer to a frame_saved_regs structure into which we put - info about the registers saved by this frame. - `fi' is a struct frame_info pointer; we fill in various fields in it - to reflect the offsets of the arg pointer and the locals pointer. */ - -static CORE_ADDR -examine_prologue (ip, limit, frame_sp, fsr, fi) - register CORE_ADDR ip; - register CORE_ADDR limit; - CORE_ADDR frame_sp; - struct frame_saved_regs *fsr; - struct frame_info *fi; -{ - register CORE_ADDR next_ip; - register int src; - unsigned int insn; - int size, offset; - char must_adjust[32]; /* If set, must adjust offsets in fsr */ - int sp_offset = -1; /* -1 means not set (valid must be mult of 8) */ - int fp_offset = -1; /* -1 means not set */ - CORE_ADDR frame_fp; - CORE_ADDR prologue_end = 0; - - memset (must_adjust, '\0', sizeof (must_adjust)); - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn); - - while (next_ip) - { - struct prologue_insns *pip; - - for (pip=prologue_insn_tbl; (insn & pip->mask) != pip->insn; ) - if (++pip >= prologue_insn_tbl + sizeof prologue_insn_tbl) - goto end_of_prologue_found; /* not a prologue insn */ - - switch (pip->action) - { - case PIA_NOTE_ST: - case PIA_NOTE_STD: - if (sp_offset != -1) { - src = ST_SRC (insn); - offset = ST_OFFSET (insn); - must_adjust[src] = 1; - fsr->regs[src++] = offset; /* Will be adjusted later */ - if (pip->action == PIA_NOTE_STD && src < 32) - { - offset += 4; - must_adjust[src] = 1; - fsr->regs[src++] = offset; - } - } - else - goto end_of_prologue_found; - break; - case PIA_NOTE_SP_ADJUSTMENT: - if (sp_offset == -1) - sp_offset = -SUBU_OFFSET (insn); - else - goto end_of_prologue_found; - break; - case PIA_NOTE_FP_ASSIGNMENT: - if (fp_offset == -1) - fp_offset = ADDU_OFFSET (insn); - else - goto end_of_prologue_found; - break; - case PIA_NOTE_PROLOGUE_END: - if (!prologue_end) - prologue_end = ip; - break; - case PIA_SKIP: - default : - /* Do nothing */ - break; - } - - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn); - } - -end_of_prologue_found: - - if (prologue_end) - ip = prologue_end; - - /* We're done with the prologue. If we don't care about the stack - frame itself, just return. (Note that fsr->regs has been trashed, - but the one caller who calls with fi==0 passes a dummy there.) */ - - if (fi == 0) - return ip; - - /* - OK, now we have: - - sp_offset original (before any alloca calls) displacement of SP - (will be negative). - - fp_offset displacement from original SP to the FP for this frame - or -1. - - fsr->regs[0..31] displacement from original SP to the stack - location where reg[0..31] is stored. - - must_adjust[0..31] set if corresponding offset was set. - - If alloca has been called between the function prologue and the current - IP, then the current SP (frame_sp) will not be the original SP as set by - the function prologue. If the current SP is not the original SP, then the - compiler will have allocated an FP for this frame, fp_offset will be set, - and we can use it to calculate the original SP. - - Then, we figure out where the arguments and locals are, and relocate the - offsets in fsr->regs to absolute addresses. */ - - if (fp_offset != -1) { - /* We have a frame pointer, so get it, and base our calc's on it. */ - frame_fp = (CORE_ADDR) read_next_frame_reg (fi->next, ACTUAL_FP_REGNUM); - frame_sp = frame_fp - fp_offset; - } else { - /* We have no frame pointer, therefore frame_sp is still the same value - as set by prologue. But where is the frame itself? */ - if (must_adjust[SRP_REGNUM]) { - /* Function header saved SRP (r1), the return address. Frame starts - 4 bytes down from where it was saved. */ - frame_fp = frame_sp + fsr->regs[SRP_REGNUM] - 4; - fi->locals_pointer = frame_fp; - } else { - /* Function header didn't save SRP (r1), so we are in a leaf fn or - are otherwise confused. */ - frame_fp = -1; - } - } - - /* The locals are relative to the FP (whether it exists as an allocated - register, or just as an assumed offset from the SP) */ - fi->locals_pointer = frame_fp; - - /* The arguments are just above the SP as it was before we adjusted it - on entry. */ - fi->args_pointer = frame_sp - sp_offset; - - /* Now that we know the SP value used by the prologue, we know where - it saved all the registers. */ - for (src = 0; src < 32; src++) - if (must_adjust[src]) - fsr->regs[src] += frame_sp; - - /* The saved value of the SP is always known. */ - /* (we hope...) */ - if (fsr->regs[SP_REGNUM] != 0 - && fsr->regs[SP_REGNUM] != frame_sp - sp_offset) - fprintf_unfiltered(gdb_stderr, "Bad saved SP value %x != %x, offset %x!\n", - fsr->regs[SP_REGNUM], - frame_sp - sp_offset, sp_offset); - - fsr->regs[SP_REGNUM] = frame_sp - sp_offset; - - return (ip); -} - -/* Given an ip value corresponding to the start of a function, - return the ip of the first instruction after the function - prologue. */ - -CORE_ADDR -skip_prologue (ip) - CORE_ADDR (ip); -{ - struct frame_saved_regs saved_regs_dummy; - struct symtab_and_line sal; - CORE_ADDR limit; - - sal = find_pc_line (ip, 0); - limit = (sal.end) ? sal.end : 0xffffffff; - - return (examine_prologue (ip, limit, (CORE_ADDR) 0, &saved_regs_dummy, - (struct frame_info *)0 )); -} - -/* 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. - - We cache the result of doing this in the frame_obstack, since it is - fairly expensive. */ - -void -frame_find_saved_regs (fi, fsr) - struct frame_info *fi; - struct frame_saved_regs *fsr; -{ - register struct frame_saved_regs *cache_fsr; - CORE_ADDR ip; - struct symtab_and_line sal; - CORE_ADDR limit; - - if (!fi->fsr) - { - cache_fsr = (struct frame_saved_regs *) - frame_obstack_alloc (sizeof (struct frame_saved_regs)); - memset (cache_fsr, '\0', sizeof (struct frame_saved_regs)); - fi->fsr = cache_fsr; - - /* Find the start and end of the function prologue. If the PC - is in the function prologue, we only consider the part that - has executed already. In the case where the PC is not in - the function prologue, we set limit to two instructions beyond - where the prologue ends in case if any of the prologue instructions - were moved into a delay slot of a branch instruction. */ - - ip = get_pc_function_start (fi->pc); - sal = find_pc_line (ip, 0); - limit = (sal.end && sal.end < fi->pc) ? sal.end + 2 * BYTES_PER_88K_INSN - : fi->pc; - - /* This will fill in fields in *fi as well as in cache_fsr. */ -#ifdef SIGTRAMP_FRAME_FIXUP - if (fi->signal_handler_caller) - SIGTRAMP_FRAME_FIXUP(fi->frame); -#endif - examine_prologue (ip, limit, fi->frame, cache_fsr, fi); -#ifdef SIGTRAMP_SP_FIXUP - if (fi->signal_handler_caller && fi->fsr->regs[SP_REGNUM]) - SIGTRAMP_SP_FIXUP(fi->fsr->regs[SP_REGNUM]); -#endif - } - - if (fsr) - *fsr = *fi->fsr; -} - -/* Return the address of the locals block for the frame - described by FI. Returns 0 if the address is unknown. - NOTE! Frame locals are referred to by negative offsets from the - argument pointer, so this is the same as frame_args_address(). */ - -CORE_ADDR -frame_locals_address (fi) - struct frame_info *fi; -{ - struct frame_saved_regs fsr; - - if (fi->args_pointer) /* Cached value is likely there. */ - return fi->args_pointer; - - /* Nope, generate it. */ - - get_frame_saved_regs (fi, &fsr); - - return fi->args_pointer; -} - -/* Return the address of the argument block for the frame - described by FI. Returns 0 if the address is unknown. */ - -CORE_ADDR -frame_args_address (fi) - struct frame_info *fi; -{ - struct frame_saved_regs fsr; - - if (fi->args_pointer) /* Cached value is likely there. */ - return fi->args_pointer; - - /* Nope, generate it. */ - - get_frame_saved_regs (fi, &fsr); - - return fi->args_pointer; -} - -/* Return the saved PC from this frame. - - If the frame has a memory copy of SRP_REGNUM, use that. If not, - just use the register SRP_REGNUM itself. */ - -CORE_ADDR -frame_saved_pc (frame) - struct frame_info *frame; -{ - return read_next_frame_reg(frame, SRP_REGNUM); -} - - -#define DUMMY_FRAME_SIZE 192 - -static void -write_word (sp, word) - CORE_ADDR sp; - ULONGEST word; -{ - register int len = REGISTER_SIZE; - char buffer[MAX_REGISTER_RAW_SIZE]; - - store_unsigned_integer (buffer, len, word); - write_memory (sp, buffer, len); -} - -void -m88k_push_dummy_frame() -{ - register CORE_ADDR sp = read_register (SP_REGNUM); - register int rn; - int offset; - - sp -= DUMMY_FRAME_SIZE; /* allocate a bunch of space */ - - for (rn = 0, offset = 0; rn <= SP_REGNUM; rn++, offset+=4) - write_word (sp+offset, read_register(rn)); - - write_word (sp+offset, read_register (SXIP_REGNUM)); - offset += 4; - - write_word (sp+offset, read_register (SNIP_REGNUM)); - offset += 4; - - write_word (sp+offset, read_register (SFIP_REGNUM)); - offset += 4; - - write_word (sp+offset, read_register (PSR_REGNUM)); - offset += 4; - - write_word (sp+offset, read_register (FPSR_REGNUM)); - offset += 4; - - write_word (sp+offset, read_register (FPCR_REGNUM)); - offset += 4; - - write_register (SP_REGNUM, sp); - write_register (ACTUAL_FP_REGNUM, sp); -} - -void -pop_frame () -{ - register struct frame_info *frame = get_current_frame (); - register CORE_ADDR fp; - register int regnum; - struct frame_saved_regs fsr; - - fp = FRAME_FP (frame); - get_frame_saved_regs (frame, &fsr); - - if (PC_IN_CALL_DUMMY (read_pc (), read_register (SP_REGNUM), FRAME_FP (fi))) - { - /* FIXME: I think get_frame_saved_regs should be handling this so - that we can deal with the saved registers properly (e.g. frame - 1 is a call dummy, the user types "frame 2" and then "print $ps"). */ - register CORE_ADDR sp = read_register (ACTUAL_FP_REGNUM); - int offset; - - for (regnum = 0, offset = 0; regnum <= SP_REGNUM; regnum++, offset+=4) - (void) write_register (regnum, read_memory_integer (sp+offset, 4)); - - write_register (SXIP_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - write_register (SNIP_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - write_register (SFIP_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - write_register (PSR_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - write_register (FPSR_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - write_register (FPCR_REGNUM, read_memory_integer (sp+offset, 4)); - offset += 4; - - } - else - { - for (regnum = FP_REGNUM ; regnum > 0 ; regnum--) - if (fsr.regs[regnum]) - write_register (regnum, - read_memory_integer (fsr.regs[regnum], 4)); - write_pc (frame_saved_pc (frame)); - } - reinit_frame_cache (); -} - -void -_initialize_m88k_tdep () -{ - tm_print_insn = print_insn_m88k; -} |