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Diffstat (limited to 'gdb/m32r-tdep.c')
| -rw-r--r-- | gdb/m32r-tdep.c | 704 |
1 files changed, 0 insertions, 704 deletions
diff --git a/gdb/m32r-tdep.c b/gdb/m32r-tdep.c deleted file mode 100644 index b4ee777..0000000 --- a/gdb/m32r-tdep.c +++ /dev/null @@ -1,704 +0,0 @@ -/* Target-dependent code for the Mitsubishi m32r for GDB, the GNU debugger. - Copyright 1996, 1998, 1999, 2000, 2001 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 "target.h" -#include "value.h" -#include "bfd.h" -#include "gdb_string.h" -#include "gdbcore.h" -#include "symfile.h" -#include "regcache.h" - -/* Function: m32r_use_struct_convention - Return nonzero if call_function should allocate stack space for a - struct return? */ -int -m32r_use_struct_convention (int gcc_p, struct type *type) -{ - return (TYPE_LENGTH (type) > 8); -} - -/* Function: frame_find_saved_regs - Return the frame_saved_regs structure for the frame. - Doesn't really work for dummy frames, but it does pass back - an empty frame_saved_regs, so I guess that's better than total failure */ - -void -m32r_frame_find_saved_regs (struct frame_info *fi, - struct frame_saved_regs *regaddr) -{ - memcpy (regaddr, &fi->fsr, sizeof (struct frame_saved_regs)); -} - -/* Turn this on if you want to see just how much instruction decoding - if being done, its quite a lot - */ -#if 0 -static void -dump_insn (char *commnt, CORE_ADDR pc, int insn) -{ - printf_filtered (" %s %08x %08x ", - commnt, (unsigned int) pc, (unsigned int) insn); - TARGET_PRINT_INSN (pc, &tm_print_insn_info); - printf_filtered ("\n"); -} -#define insn_debug(args) { printf_filtered args; } -#else -#define dump_insn(a,b,c) {} -#define insn_debug(args) {} -#endif - -#define DEFAULT_SEARCH_LIMIT 44 - -/* Function: scan_prologue - This function decodes the target function prologue to determine - 1) the size of the stack frame, and 2) which registers are saved on it. - It saves the offsets of saved regs in the frame_saved_regs argument, - and returns the frame size. */ - -/* - The sequence it currently generates is: - - if (varargs function) { ddi sp,#n } - push registers - if (additional stack <= 256) { addi sp,#-stack } - else if (additional stack < 65k) { add3 sp,sp,#-stack - - } else if (additional stack) { - seth sp,#(stack & 0xffff0000) - or3 sp,sp,#(stack & 0x0000ffff) - sub sp,r4 - } - if (frame pointer) { - mv sp,fp - } - - These instructions are scheduled like everything else, so you should stop at - the first branch instruction. - - */ - -/* This is required by skip prologue and by m32r_init_extra_frame_info. - The results of decoding a prologue should be cached because this - thrashing is getting nuts. - I am thinking of making a container class with two indexes, name and - address. It may be better to extend the symbol table. - */ - -static void -decode_prologue (CORE_ADDR start_pc, CORE_ADDR scan_limit, CORE_ADDR *pl_endptr, /* var parameter */ - unsigned long *framelength, struct frame_info *fi, - struct frame_saved_regs *fsr) -{ - unsigned long framesize; - int insn; - int op1; - int maybe_one_more = 0; - CORE_ADDR after_prologue = 0; - CORE_ADDR after_stack_adjust = 0; - CORE_ADDR current_pc; - - - framesize = 0; - after_prologue = 0; - insn_debug (("rd prolog l(%d)\n", scan_limit - current_pc)); - - for (current_pc = start_pc; current_pc < scan_limit; current_pc += 2) - { - - insn = read_memory_unsigned_integer (current_pc, 2); - dump_insn ("insn-1", current_pc, insn); /* MTZ */ - - /* If this is a 32 bit instruction, we dont want to examine its - immediate data as though it were an instruction */ - if (current_pc & 0x02) - { /* Clear the parallel execution bit from 16 bit instruction */ - if (maybe_one_more) - { /* The last instruction was a branch, usually terminates - the series, but if this is a parallel instruction, - it may be a stack framing instruction */ - if (!(insn & 0x8000)) - { - insn_debug (("Really done")); - break; /* nope, we are really done */ - } - } - insn &= 0x7fff; /* decode this instruction further */ - } - else - { - if (maybe_one_more) - break; /* This isnt the one more */ - if (insn & 0x8000) - { - insn_debug (("32 bit insn\n")); - if (current_pc == scan_limit) - scan_limit += 2; /* extend the search */ - current_pc += 2; /* skip the immediate data */ - if (insn == 0x8faf) /* add3 sp, sp, xxxx */ - /* add 16 bit sign-extended offset */ - { - insn_debug (("stack increment\n")); - framesize += -((short) read_memory_unsigned_integer (current_pc, 2)); - } - else - { - if (((insn >> 8) == 0xe4) && /* ld24 r4, xxxxxx; sub sp, r4 */ - read_memory_unsigned_integer (current_pc + 2, 2) == 0x0f24) - { /* subtract 24 bit sign-extended negative-offset */ - dump_insn ("insn-2", current_pc + 2, insn); - insn = read_memory_unsigned_integer (current_pc - 2, 4); - dump_insn ("insn-3(l4)", current_pc - 2, insn); - if (insn & 0x00800000) /* sign extend */ - insn |= 0xff000000; /* negative */ - else - insn &= 0x00ffffff; /* positive */ - framesize += insn; - } - } - after_prologue = current_pc; - continue; - } - } - op1 = insn & 0xf000; /* isolate just the first nibble */ - - if ((insn & 0xf0ff) == 0x207f) - { /* st reg, @-sp */ - int regno; - insn_debug (("push\n")); -#if 0 /* No, PUSH FP is not an indication that we will use a frame pointer. */ - if (((insn & 0xffff) == 0x2d7f) && fi) - fi->using_frame_pointer = 1; -#endif - framesize += 4; -#if 0 -/* Why should we increase the scan limit, just because we did a push? - And if there is a reason, surely we would only want to do it if we - had already reached the scan limit... */ - if (current_pc == scan_limit) - scan_limit += 2; -#endif - regno = ((insn >> 8) & 0xf); - if (fsr) /* save_regs offset */ - fsr->regs[regno] = framesize; - after_prologue = 0; - continue; - } - if ((insn >> 8) == 0x4f) /* addi sp, xx */ - /* add 8 bit sign-extended offset */ - { - int stack_adjust = (char) (insn & 0xff); - - /* there are probably two of these stack adjustments: - 1) A negative one in the prologue, and - 2) A positive one in the epilogue. - We are only interested in the first one. */ - - if (stack_adjust < 0) - { - framesize -= stack_adjust; - after_prologue = 0; - /* A frameless function may have no "mv fp, sp". - In that case, this is the end of the prologue. */ - after_stack_adjust = current_pc + 2; - } - continue; - } - if (insn == 0x1d8f) - { /* mv fp, sp */ - if (fi) - fi->using_frame_pointer = 1; /* fp is now valid */ - insn_debug (("done fp found\n")); - after_prologue = current_pc + 2; - break; /* end of stack adjustments */ - } - if (insn == 0x7000) /* Nop looks like a branch, continue explicitly */ - { - insn_debug (("nop\n")); - after_prologue = current_pc + 2; - continue; /* nop occurs between pushes */ - } - /* End of prolog if any of these are branch instructions */ - if ((op1 == 0x7000) - || (op1 == 0xb000) - || (op1 == 0xf000)) - { - after_prologue = current_pc; - insn_debug (("Done: branch\n")); - maybe_one_more = 1; - continue; - } - /* Some of the branch instructions are mixed with other types */ - if (op1 == 0x1000) - { - int subop = insn & 0x0ff0; - if ((subop == 0x0ec0) || (subop == 0x0fc0)) - { - insn_debug (("done: jmp\n")); - after_prologue = current_pc; - maybe_one_more = 1; - continue; /* jmp , jl */ - } - } - } - - if (current_pc >= scan_limit) - { - if (pl_endptr) - { -#if 1 - if (after_stack_adjust != 0) - /* We did not find a "mv fp,sp", but we DID find - a stack_adjust. Is it safe to use that as the - end of the prologue? I just don't know. */ - { - *pl_endptr = after_stack_adjust; - if (framelength) - *framelength = framesize; - } - else -#endif - /* We reached the end of the loop without finding the end - of the prologue. No way to win -- we should report failure. - The way we do that is to return the original start_pc. - GDB will set a breakpoint at the start of the function (etc.) */ - *pl_endptr = start_pc; - } - return; - } - if (after_prologue == 0) - after_prologue = current_pc; - - insn_debug ((" framesize %d, firstline %08x\n", framesize, after_prologue)); - if (framelength) - *framelength = framesize; - if (pl_endptr) - *pl_endptr = after_prologue; -} /* decode_prologue */ - -/* Function: skip_prologue - Find end of function prologue */ - -CORE_ADDR -m32r_skip_prologue (CORE_ADDR pc) -{ - CORE_ADDR func_addr, func_end; - struct symtab_and_line sal; - - /* See what the symbol table says */ - - if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) - { - sal = find_pc_line (func_addr, 0); - - if (sal.line != 0 && sal.end <= func_end) - { - - insn_debug (("BP after prologue %08x\n", sal.end)); - func_end = sal.end; - } - else - /* Either there's no line info, or the line after the prologue is after - the end of the function. In this case, there probably isn't a - prologue. */ - { - insn_debug (("No line info, line(%x) sal_end(%x) funcend(%x)\n", - sal.line, sal.end, func_end)); - func_end = min (func_end, func_addr + DEFAULT_SEARCH_LIMIT); - } - } - else - func_end = pc + DEFAULT_SEARCH_LIMIT; - decode_prologue (pc, func_end, &sal.end, 0, 0, 0); - return sal.end; -} - -static unsigned long -m32r_scan_prologue (struct frame_info *fi, struct frame_saved_regs *fsr) -{ - struct symtab_and_line sal; - CORE_ADDR prologue_start, prologue_end, current_pc; - unsigned long framesize = 0; - - /* this code essentially duplicates skip_prologue, - but we need the start address below. */ - - if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end)) - { - sal = find_pc_line (prologue_start, 0); - - if (sal.line == 0) /* no line info, use current PC */ - if (prologue_start == entry_point_address ()) - return 0; - } - else - { - prologue_start = fi->pc; - prologue_end = prologue_start + 48; /* We're in the boondocks: - allow for 16 pushes, an add, - and "mv fp,sp" */ - } -#if 0 - prologue_end = min (prologue_end, fi->pc); -#endif - insn_debug (("fipc(%08x) start(%08x) end(%08x)\n", - fi->pc, prologue_start, prologue_end)); - prologue_end = min (prologue_end, prologue_start + DEFAULT_SEARCH_LIMIT); - decode_prologue (prologue_start, prologue_end, &prologue_end, &framesize, - fi, fsr); - return framesize; -} - -/* Function: init_extra_frame_info - This function actually figures out the frame address for a given pc and - sp. This is tricky on the m32r because we sometimes don't use an explicit - frame pointer, and the previous stack pointer isn't necessarily recorded - on the stack. The only reliable way to get this info is to - examine the prologue. */ - -void -m32r_init_extra_frame_info (struct frame_info *fi) -{ - int reg; - - if (fi->next) - fi->pc = FRAME_SAVED_PC (fi->next); - - memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs); - - if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) - { - /* We need to setup fi->frame here because run_stack_dummy gets it wrong - by assuming it's always FP. */ - fi->frame = generic_read_register_dummy (fi->pc, fi->frame, SP_REGNUM); - fi->framesize = 0; - return; - } - else - { - fi->using_frame_pointer = 0; - fi->framesize = m32r_scan_prologue (fi, &fi->fsr); - - if (!fi->next) - if (fi->using_frame_pointer) - { - fi->frame = read_register (FP_REGNUM); - } - else - fi->frame = read_register (SP_REGNUM); - else - /* fi->next means this is not the innermost frame */ if (fi->using_frame_pointer) - /* we have an FP */ - if (fi->next->fsr.regs[FP_REGNUM] != 0) /* caller saved our FP */ - fi->frame = read_memory_integer (fi->next->fsr.regs[FP_REGNUM], 4); - for (reg = 0; reg < NUM_REGS; reg++) - if (fi->fsr.regs[reg] != 0) - fi->fsr.regs[reg] = fi->frame + fi->framesize - fi->fsr.regs[reg]; - } -} - -/* Function: m32r_virtual_frame_pointer - Return the register that the function uses for a frame pointer, - plus any necessary offset to be applied to the register before - any frame pointer offsets. */ - -void -m32r_virtual_frame_pointer (CORE_ADDR pc, long *reg, long *offset) -{ - struct frame_info fi; - - /* Set up a dummy frame_info. */ - fi.next = NULL; - fi.prev = NULL; - fi.frame = 0; - fi.pc = pc; - - /* Analyze the prolog and fill in the extra info. */ - m32r_init_extra_frame_info (&fi); - - - /* Results will tell us which type of frame it uses. */ - if (fi.using_frame_pointer) - { - *reg = FP_REGNUM; - *offset = 0; - } - else - { - *reg = SP_REGNUM; - *offset = 0; - } -} - -/* Function: find_callers_reg - Find REGNUM on the stack. Otherwise, it's in an active register. One thing - we might want to do here is to check REGNUM against the clobber mask, and - somehow flag it as invalid if it isn't saved on the stack somewhere. This - would provide a graceful failure mode when trying to get the value of - caller-saves registers for an inner frame. */ - -CORE_ADDR -m32r_find_callers_reg (struct frame_info *fi, int regnum) -{ - for (; fi; fi = fi->next) - if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) - return generic_read_register_dummy (fi->pc, fi->frame, regnum); - else if (fi->fsr.regs[regnum] != 0) - return read_memory_integer (fi->fsr.regs[regnum], - REGISTER_RAW_SIZE (regnum)); - return read_register (regnum); -} - -/* Function: frame_chain - 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 m32r, we save the frame size when we initialize the frame_info. */ - -CORE_ADDR -m32r_frame_chain (struct frame_info *fi) -{ - CORE_ADDR fn_start, callers_pc, fp; - - /* is this a dummy frame? */ - if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) - return fi->frame; /* dummy frame same as caller's frame */ - - /* is caller-of-this a dummy frame? */ - callers_pc = FRAME_SAVED_PC (fi); /* find out who called us: */ - fp = m32r_find_callers_reg (fi, FP_REGNUM); - if (PC_IN_CALL_DUMMY (callers_pc, fp, fp)) - return fp; /* dummy frame's frame may bear no relation to ours */ - - if (find_pc_partial_function (fi->pc, 0, &fn_start, 0)) - if (fn_start == entry_point_address ()) - return 0; /* in _start fn, don't chain further */ - if (fi->framesize == 0) - { - printf_filtered ("cannot determine frame size @ %s , pc(%s)\n", - paddr (fi->frame), - paddr (fi->pc)); - return 0; - } - insn_debug (("m32rx frame %08x\n", fi->frame + fi->framesize)); - return fi->frame + fi->framesize; -} - -/* Function: push_return_address (pc) - Set up the return address for the inferior function call. - Necessary for targets that don't actually execute a JSR/BSR instruction - (ie. when using an empty CALL_DUMMY) */ - -CORE_ADDR -m32r_push_return_address (CORE_ADDR pc, CORE_ADDR sp) -{ - write_register (RP_REGNUM, CALL_DUMMY_ADDRESS ()); - return sp; -} - - -/* Function: pop_frame - Discard from the stack the innermost frame, - restoring all saved registers. */ - -struct frame_info * -m32r_pop_frame (struct frame_info *frame) -{ - int regnum; - - if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame)) - generic_pop_dummy_frame (); - else - { - for (regnum = 0; regnum < NUM_REGS; regnum++) - if (frame->fsr.regs[regnum] != 0) - write_register (regnum, - read_memory_integer (frame->fsr.regs[regnum], 4)); - - write_register (PC_REGNUM, FRAME_SAVED_PC (frame)); - write_register (SP_REGNUM, read_register (FP_REGNUM)); - if (read_register (PSW_REGNUM) & 0x80) - write_register (SPU_REGNUM, read_register (SP_REGNUM)); - else - write_register (SPI_REGNUM, read_register (SP_REGNUM)); - } - flush_cached_frames (); - return NULL; -} - -/* Function: frame_saved_pc - Find the caller of this frame. We do this by seeing if RP_REGNUM is saved - in the stack anywhere, otherwise we get it from the registers. */ - -CORE_ADDR -m32r_frame_saved_pc (struct frame_info *fi) -{ - if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) - return generic_read_register_dummy (fi->pc, fi->frame, PC_REGNUM); - else - return m32r_find_callers_reg (fi, RP_REGNUM); -} - -/* Function: push_arguments - Setup the function arguments for calling a function in the inferior. - - On the Mitsubishi M32R architecture, there are four registers (R0 to R3) - which are dedicated for passing function arguments. Up to the first - four arguments (depending on size) may go into these registers. - The rest go on the stack. - - Arguments that are smaller than 4 bytes will still take up a whole - register or a whole 32-bit word on the stack, and will be - right-justified in the register or the stack word. This includes - chars, shorts, and small aggregate types. - - Arguments of 8 bytes size are split between two registers, if - available. If only one register is available, the argument will - be split between the register and the stack. Otherwise it is - passed entirely on the stack. Aggregate types with sizes between - 4 and 8 bytes are passed entirely on the stack, and are left-justified - within the double-word (as opposed to aggregates smaller than 4 bytes - which are right-justified). - - Aggregates of greater than 8 bytes are first copied onto the stack, - and then a pointer to the copy is passed in the place of the normal - argument (either in a register if available, or on the stack). - - Functions that must return an aggregate type can return it in the - normal return value registers (R0 and R1) if its size is 8 bytes or - less. For larger return values, the caller must allocate space for - the callee to copy the return value to. A pointer to this space is - passed as an implicit first argument, always in R0. */ - -CORE_ADDR -m32r_push_arguments (int nargs, struct value **args, CORE_ADDR sp, - unsigned char struct_return, CORE_ADDR struct_addr) -{ - int stack_offset, stack_alloc; - int argreg; - int argnum; - struct type *type; - CORE_ADDR regval; - char *val; - char valbuf[4]; - int len; - int odd_sized_struct; - - /* first force sp to a 4-byte alignment */ - sp = sp & ~3; - - argreg = ARG0_REGNUM; - /* The "struct return pointer" pseudo-argument goes in R0 */ - if (struct_return) - write_register (argreg++, struct_addr); - - /* Now make sure there's space on the stack */ - for (argnum = 0, stack_alloc = 0; - argnum < nargs; argnum++) - stack_alloc += ((TYPE_LENGTH (VALUE_TYPE (args[argnum])) + 3) & ~3); - sp -= stack_alloc; /* make room on stack for args */ - - - /* Now load as many as possible of the first arguments into - registers, and push the rest onto the stack. There are 16 bytes - in four registers available. Loop thru args from first to last. */ - - argreg = ARG0_REGNUM; - for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++) - { - type = VALUE_TYPE (args[argnum]); - len = TYPE_LENGTH (type); - memset (valbuf, 0, sizeof (valbuf)); - if (len < 4) - { /* value gets right-justified in the register or stack word */ - memcpy (valbuf + (4 - len), - (char *) VALUE_CONTENTS (args[argnum]), len); - val = valbuf; - } - else - val = (char *) VALUE_CONTENTS (args[argnum]); - - if (len > 4 && (len & 3) != 0) - odd_sized_struct = 1; /* such structs go entirely on stack */ - else - odd_sized_struct = 0; - while (len > 0) - { - if (argreg > ARGLAST_REGNUM || odd_sized_struct) - { /* must go on the stack */ - write_memory (sp + stack_offset, val, 4); - stack_offset += 4; - } - /* NOTE WELL!!!!! This is not an "else if" clause!!! - That's because some *&^%$ things get passed on the stack - AND in the registers! */ - if (argreg <= ARGLAST_REGNUM) - { /* there's room in a register */ - regval = extract_address (val, REGISTER_RAW_SIZE (argreg)); - write_register (argreg++, regval); - } - /* Store the value 4 bytes at a time. This means that things - larger than 4 bytes may go partly in registers and partly - on the stack. */ - len -= REGISTER_RAW_SIZE (argreg); - val += REGISTER_RAW_SIZE (argreg); - } - } - return sp; -} - -/* Function: fix_call_dummy - If there is real CALL_DUMMY code (eg. on the stack), this function - has the responsability to insert the address of the actual code that - is the target of the target function call. */ - -void -m32r_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs, - struct value **args, struct type *type, int gcc_p) -{ - /* ld24 r8, <(imm24) fun> */ - *(unsigned long *) (dummy) = (fun & 0x00ffffff) | 0xe8000000; -} - - -/* Function: m32r_write_sp - Because SP is really a read-only register that mirrors either SPU or SPI, - we must actually write one of those two as well, depending on PSW. */ - -void -m32r_write_sp (CORE_ADDR val) -{ - unsigned long psw = read_register (PSW_REGNUM); - - if (psw & 0x80) /* stack mode: user or interrupt */ - write_register (SPU_REGNUM, val); - else - write_register (SPI_REGNUM, val); - write_register (SP_REGNUM, val); -} - -void -_initialize_m32r_tdep (void) -{ - tm_print_insn = print_insn_m32r; -} |