diff options
Diffstat (limited to 'gdb/mcore-tdep.c')
| -rw-r--r-- | gdb/mcore-tdep.c | 996 |
1 files changed, 0 insertions, 996 deletions
diff --git a/gdb/mcore-tdep.c b/gdb/mcore-tdep.c deleted file mode 100644 index 184f7b57e50..00000000000 --- a/gdb/mcore-tdep.c +++ /dev/null @@ -1,996 +0,0 @@ -/* Target-machine dependent code for Motorola MCore for GDB, the GNU debugger - Copyright 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 "symtab.h" -#include "value.h" -#include "gdbcmd.h" -#include "regcache.h" -#include "symfile.h" -#include "gdbcore.h" -#include "inferior.h" - -/* Functions declared and used only in this file */ - -static CORE_ADDR mcore_analyze_prologue (struct frame_info *fi, CORE_ADDR pc, int skip_prologue); - -static struct frame_info *analyze_dummy_frame (CORE_ADDR pc, CORE_ADDR frame); - -static int get_insn (CORE_ADDR pc); - -/* Functions exported from this file */ - -int mcore_use_struct_convention (int gcc_p, struct type *type); - -void _initialize_mcore (void); - -void mcore_init_extra_frame_info (struct frame_info *fi); - -CORE_ADDR mcore_frame_saved_pc (struct frame_info *fi); - -CORE_ADDR mcore_find_callers_reg (struct frame_info *fi, int regnum); - -CORE_ADDR mcore_frame_args_address (struct frame_info *fi); - -CORE_ADDR mcore_frame_locals_address (struct frame_info *fi); - -CORE_ADDR mcore_push_return_address (CORE_ADDR pc, CORE_ADDR sp); - -CORE_ADDR mcore_push_arguments (int nargs, struct value ** args, CORE_ADDR sp, - unsigned char struct_return, CORE_ADDR struct_addr); - -void mcore_pop_frame (struct frame_info *fi); - -CORE_ADDR mcore_skip_prologue (CORE_ADDR pc); - -CORE_ADDR mcore_frame_chain (struct frame_info *fi); - -unsigned char *mcore_breakpoint_from_pc (CORE_ADDR * bp_addr, int *bp_size); - -int mcore_use_struct_convention (int gcc_p, struct type *type); - -void mcore_store_return_value (struct type *type, char *valbuf); - -CORE_ADDR mcore_extract_struct_value_address (char *regbuf); - -void mcore_extract_return_value (struct type *type, char *regbuf, char *valbuf); - -#ifdef MCORE_DEBUG -int mcore_debug = 0; -#endif - -/* The registers of the Motorola MCore processors */ -/* *INDENT-OFF* */ -char *mcore_register_names[] = -{ "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", - "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", - "ar0", "ar1", "ar2", "ar3", "ar4", "ar5", "ar6", "ar7", - "ar8", "ar9", "ar10", "ar11", "ar12", "ar13", "ar14", "ar15", - "psr", "vbr", "epsr", "fpsr", "epc", "fpc", "ss0", "ss1", - "ss2", "ss3", "ss4", "gcr", "gsr", "cr13", "cr14", "cr15", - "cr16", "cr17", "cr18", "cr19", "cr20", "cr21", "cr22", "cr23", - "cr24", "cr25", "cr26", "cr27", "cr28", "cr29", "cr30", "cr31", - "pc" }; -/* *INDENT-ON* */ - - - -/* Additional info that we use for managing frames */ -struct frame_extra_info - { - /* A generic status word */ - int status; - - /* Size of this frame */ - int framesize; - - /* The register that is acting as a frame pointer, if - it is being used. This is undefined if status - does not contain the flag MY_FRAME_IN_FP. */ - int fp_regnum; - }; - -/* frame_extra_info status flags */ - -/* The base of the current frame is actually in the stack pointer. - This happens when there is no frame pointer (MCore ABI does not - require a frame pointer) or when we're stopped in the prologue or - epilogue itself. In these cases, mcore_analyze_prologue will need - to update fi->frame before returning or analyzing the register - save instructions. */ -#define MY_FRAME_IN_SP 0x1 - -/* The base of the current frame is in a frame pointer register. - This register is noted in frame_extra_info->fp_regnum. - - Note that the existence of an FP might also indicate that the - function has called alloca. */ -#define MY_FRAME_IN_FP 0x2 - -/* This flag is set to indicate that this frame is the top-most - frame. This tells frame chain not to bother trying to unwind - beyond this frame. */ -#define NO_MORE_FRAMES 0x4 - -/* Instruction macros used for analyzing the prologue */ -#define IS_SUBI0(x) (((x) & 0xfe0f) == 0x2400) /* subi r0,oimm5 */ -#define IS_STM(x) (((x) & 0xfff0) == 0x0070) /* stm rf-r15,r0 */ -#define IS_STWx0(x) (((x) & 0xf00f) == 0x9000) /* stw rz,(r0,disp) */ -#define IS_STWxy(x) (((x) & 0xf000) == 0x9000) /* stw rx,(ry,disp) */ -#define IS_MOVx0(x) (((x) & 0xfff0) == 0x1200) /* mov rn,r0 */ -#define IS_LRW1(x) (((x) & 0xff00) == 0x7100) /* lrw r1,literal */ -#define IS_MOVI1(x) (((x) & 0xf80f) == 0x6001) /* movi r1,imm7 */ -#define IS_BGENI1(x) (((x) & 0xfe0f) == 0x3201) /* bgeni r1,imm5 */ -#define IS_BMASKI1(x) (((x) & 0xfe0f) == 0x2C01) /* bmaski r1,imm5 */ -#define IS_ADDI1(x) (((x) & 0xfe0f) == 0x2001) /* addi r1,oimm5 */ -#define IS_SUBI1(x) (((x) & 0xfe0f) == 0x2401) /* subi r1,oimm5 */ -#define IS_RSUBI1(x) (((x) & 0xfe0f) == 0x2801) /* rsubi r1,imm5 */ -#define IS_NOT1(x) (((x) & 0xffff) == 0x01f1) /* not r1 */ -#define IS_ROTLI1(x) (((x) & 0xfe0f) == 0x3801) /* rotli r1,imm5 */ -#define IS_BSETI1(x) (((x) & 0xfe0f) == 0x3401) /* bseti r1,imm5 */ -#define IS_BCLRI1(x) (((x) & 0xfe0f) == 0x3001) /* bclri r1,imm5 */ -#define IS_IXH1(x) (((x) & 0xffff) == 0x1d11) /* ixh r1,r1 */ -#define IS_IXW1(x) (((x) & 0xffff) == 0x1511) /* ixw r1,r1 */ -#define IS_SUB01(x) (((x) & 0xffff) == 0x0510) /* subu r0,r1 */ -#define IS_RTS(x) (((x) & 0xffff) == 0x00cf) /* jmp r15 */ - -#define IS_R1_ADJUSTER(x) \ - (IS_ADDI1(x) || IS_SUBI1(x) || IS_ROTLI1(x) || IS_BSETI1(x) \ - || IS_BCLRI1(x) || IS_RSUBI1(x) || IS_NOT1(x) \ - || IS_IXH1(x) || IS_IXW1(x)) - - -#ifdef MCORE_DEBUG -static void -mcore_dump_insn (char *commnt, CORE_ADDR pc, int insn) -{ - if (mcore_debug) - { - printf_filtered ("MCORE: %s %08x %08x ", - commnt, (unsigned int) pc, (unsigned int) insn); - TARGET_PRINT_INSN (pc, &tm_print_insn_info); - printf_filtered ("\n"); - } -} -#define mcore_insn_debug(args) { if (mcore_debug) printf_filtered args; } -#else /* !MCORE_DEBUG */ -#define mcore_dump_insn(a,b,c) {} -#define mcore_insn_debug(args) {} -#endif - -/* Given the address at which to insert a breakpoint (BP_ADDR), - what will that breakpoint be? - - For MCore, we have a breakpoint instruction. Since all MCore - instructions are 16 bits, this is all we need, regardless of - address. bpkt = 0x0000 */ - -unsigned char * -mcore_breakpoint_from_pc (CORE_ADDR * bp_addr, int *bp_size) -{ - static char breakpoint[] = - {0x00, 0x00}; - *bp_size = 2; - return breakpoint; -} - -/* Helper function for several routines below. This funtion simply - sets up a fake, aka dummy, frame (not a _call_ dummy frame) that - we can analyze with mcore_analyze_prologue. */ - -static struct frame_info * -analyze_dummy_frame (CORE_ADDR pc, CORE_ADDR frame) -{ - static struct frame_info *dummy = NULL; - - if (dummy == NULL) - { - dummy = (struct frame_info *) xmalloc (sizeof (struct frame_info)); - dummy->saved_regs = (CORE_ADDR *) xmalloc (SIZEOF_FRAME_SAVED_REGS); - dummy->extra_info = - (struct frame_extra_info *) xmalloc (sizeof (struct frame_extra_info)); - } - - dummy->next = NULL; - dummy->prev = NULL; - dummy->pc = pc; - dummy->frame = frame; - dummy->extra_info->status = 0; - dummy->extra_info->framesize = 0; - memset (dummy->saved_regs, '\000', SIZEOF_FRAME_SAVED_REGS); - mcore_analyze_prologue (dummy, 0, 0); - return dummy; -} - -/* Function prologues on the Motorola MCore processors consist of: - - - adjustments to the stack pointer (r1 used as scratch register) - - store word/multiples that use r0 as the base address - - making a copy of r0 into another register (a "frame" pointer) - - Note that the MCore really doesn't have a real frame pointer. - Instead, the compiler may copy the SP into a register (usually - r8) to act as an arg pointer. For our target-dependent purposes, - the frame info's "frame" member will be the beginning of the - frame. The SP could, in fact, point below this. - - The prologue ends when an instruction fails to meet either of - the first two criteria or when an FP is made. We make a special - exception for gcc. When compiling unoptimized code, gcc will - setup stack slots. We need to make sure that we skip the filling - of these stack slots as much as possible. This is only done - when SKIP_PROLOGUE is set, so that it does not mess up - backtraces. */ - -/* Analyze the prologue of frame FI to determine where registers are saved, - the end of the prologue, etc. Return the address of the first line - of "real" code (i.e., the end of the prologue). */ - -static CORE_ADDR -mcore_analyze_prologue (struct frame_info *fi, CORE_ADDR pc, int skip_prologue) -{ - CORE_ADDR func_addr, func_end, addr, stop; - CORE_ADDR stack_size; - int insn, rn; - int status; - int fp_regnum = 0; /* dummy, valid when (flags & MY_FRAME_IN_FP) */ - int flags; - int framesize; - int register_offsets[NUM_REGS]; - char *name; - - /* If provided, use the PC in the frame to look up the - start of this function. */ - pc = (fi == NULL ? pc : fi->pc); - - /* Find the start of this function. */ - status = find_pc_partial_function (pc, &name, &func_addr, &func_end); - - /* If the start of this function could not be found or if the debbuger - is stopped at the first instruction of the prologue, do nothing. */ - if (status == 0) - return pc; - - /* If the debugger is entry function, give up. */ - if (func_addr == entry_point_address ()) - { - if (fi != NULL) - fi->extra_info->status |= NO_MORE_FRAMES; - return pc; - } - - /* At the start of a function, our frame is in the stack pointer. */ - flags = MY_FRAME_IN_SP; - - /* Start decoding the prologue. We start by checking two special cases: - - 1. We're about to return - 2. We're at the first insn of the prologue. - - If we're about to return, our frame has already been deallocated. - If we are stopped at the first instruction of a prologue, - then our frame has not yet been set up. */ - - /* Get the first insn from memory (all MCore instructions are 16 bits) */ - mcore_insn_debug (("MCORE: starting prologue decoding\n")); - insn = get_insn (pc); - mcore_dump_insn ("got 1: ", pc, insn); - - /* Check for return. */ - if (fi != NULL && IS_RTS (insn)) - { - mcore_insn_debug (("MCORE: got jmp r15")); - if (fi->next == NULL) - fi->frame = read_sp (); - return fi->pc; - } - - /* Check for first insn of prologue */ - if (fi != NULL && fi->pc == func_addr) - { - if (fi->next == NULL) - fi->frame = read_sp (); - return fi->pc; - } - - /* Figure out where to stop scanning */ - stop = (fi ? fi->pc : func_end); - - /* Don't walk off the end of the function */ - stop = (stop > func_end ? func_end : stop); - - /* REGISTER_OFFSETS will contain offsets, from the top of the frame - (NOT the frame pointer), for the various saved registers or -1 - if the register is not saved. */ - for (rn = 0; rn < NUM_REGS; rn++) - register_offsets[rn] = -1; - - /* Analyze the prologue. Things we determine from analyzing the - prologue include: - * the size of the frame - * where saved registers are located (and which are saved) - * FP used? */ - mcore_insn_debug (("MCORE: Scanning prologue: func_addr=0x%x, stop=0x%x\n", - (unsigned int) func_addr, (unsigned int) stop)); - - framesize = 0; - for (addr = func_addr; addr < stop; addr += 2) - { - /* Get next insn */ - insn = get_insn (addr); - mcore_dump_insn ("got 2: ", addr, insn); - - if (IS_SUBI0 (insn)) - { - int offset = 1 + ((insn >> 4) & 0x1f); - mcore_insn_debug (("MCORE: got subi r0,%d; continuing\n", offset)); - framesize += offset; - continue; - } - else if (IS_STM (insn)) - { - /* Spill register(s) */ - int offset; - int start_register; - - /* BIG WARNING! The MCore ABI does not restrict functions - to taking only one stack allocation. Therefore, when - we save a register, we record the offset of where it was - saved relative to the current framesize. This will - then give an offset from the SP upon entry to our - function. Remember, framesize is NOT constant until - we're done scanning the prologue. */ - start_register = (insn & 0xf); - mcore_insn_debug (("MCORE: got stm r%d-r15,(r0)\n", start_register)); - - for (rn = start_register, offset = 0; rn <= 15; rn++, offset += 4) - { - register_offsets[rn] = framesize - offset; - mcore_insn_debug (("MCORE: r%d saved at 0x%x (offset %d)\n", rn, - register_offsets[rn], offset)); - } - mcore_insn_debug (("MCORE: continuing\n")); - continue; - } - else if (IS_STWx0 (insn)) - { - /* Spill register: see note for IS_STM above. */ - int imm; - - rn = (insn >> 8) & 0xf; - imm = (insn >> 4) & 0xf; - register_offsets[rn] = framesize - (imm << 2); - mcore_insn_debug (("MCORE: r%d saved at offset 0x%x\n", rn, register_offsets[rn])); - mcore_insn_debug (("MCORE: continuing\n")); - continue; - } - else if (IS_MOVx0 (insn)) - { - /* We have a frame pointer, so this prologue is over. Note - the register which is acting as the frame pointer. */ - flags |= MY_FRAME_IN_FP; - flags &= ~MY_FRAME_IN_SP; - fp_regnum = insn & 0xf; - mcore_insn_debug (("MCORE: Found a frame pointer: r%d\n", fp_regnum)); - - /* If we found an FP, we're at the end of the prologue. */ - mcore_insn_debug (("MCORE: end of prologue\n")); - if (skip_prologue) - continue; - - /* If we're decoding prologue, stop here. */ - addr += 2; - break; - } - else if (IS_STWxy (insn) && (flags & MY_FRAME_IN_FP) && ((insn & 0xf) == fp_regnum)) - { - /* Special case. Skip over stack slot allocs, too. */ - mcore_insn_debug (("MCORE: push arg onto stack.\n")); - continue; - } - else if (IS_LRW1 (insn) || IS_MOVI1 (insn) - || IS_BGENI1 (insn) || IS_BMASKI1 (insn)) - { - int adjust = 0; - int offset = 0; - int insn2; - - mcore_insn_debug (("MCORE: looking at large frame\n")); - if (IS_LRW1 (insn)) - { - adjust = - read_memory_integer ((addr + 2 + ((insn & 0xff) << 2)) & 0xfffffffc, 4); - } - else if (IS_MOVI1 (insn)) - adjust = (insn >> 4) & 0x7f; - else if (IS_BGENI1 (insn)) - adjust = 1 << ((insn >> 4) & 0x1f); - else /* IS_BMASKI (insn) */ - adjust = (1 << (adjust >> 4) & 0x1f) - 1; - - mcore_insn_debug (("MCORE: base framesize=0x%x\n", adjust)); - - /* May have zero or more insns which modify r1 */ - mcore_insn_debug (("MCORE: looking for r1 adjusters...\n")); - offset = 2; - insn2 = get_insn (addr + offset); - while (IS_R1_ADJUSTER (insn2)) - { - int imm; - - imm = (insn2 >> 4) & 0x1f; - mcore_dump_insn ("got 3: ", addr + offset, insn); - if (IS_ADDI1 (insn2)) - { - adjust += (imm + 1); - mcore_insn_debug (("MCORE: addi r1,%d\n", imm + 1)); - } - else if (IS_SUBI1 (insn2)) - { - adjust -= (imm + 1); - mcore_insn_debug (("MCORE: subi r1,%d\n", imm + 1)); - } - else if (IS_RSUBI1 (insn2)) - { - adjust = imm - adjust; - mcore_insn_debug (("MCORE: rsubi r1,%d\n", imm + 1)); - } - else if (IS_NOT1 (insn2)) - { - adjust = ~adjust; - mcore_insn_debug (("MCORE: not r1\n")); - } - else if (IS_ROTLI1 (insn2)) - { - adjust <<= imm; - mcore_insn_debug (("MCORE: rotli r1,%d\n", imm + 1)); - } - else if (IS_BSETI1 (insn2)) - { - adjust |= (1 << imm); - mcore_insn_debug (("MCORE: bseti r1,%d\n", imm)); - } - else if (IS_BCLRI1 (insn2)) - { - adjust &= ~(1 << imm); - mcore_insn_debug (("MCORE: bclri r1,%d\n", imm)); - } - else if (IS_IXH1 (insn2)) - { - adjust *= 3; - mcore_insn_debug (("MCORE: ix.h r1,r1\n")); - } - else if (IS_IXW1 (insn2)) - { - adjust *= 5; - mcore_insn_debug (("MCORE: ix.w r1,r1\n")); - } - - offset += 2; - insn2 = get_insn (addr + offset); - }; - - mcore_insn_debug (("MCORE: done looking for r1 adjusters\n")); - - /* If the next insn adjusts the stack pointer, we keep everything; - if not, we scrap it and we've found the end of the prologue. */ - if (IS_SUB01 (insn2)) - { - addr += offset; - framesize += adjust; - mcore_insn_debug (("MCORE: found stack adjustment of 0x%x bytes.\n", adjust)); - mcore_insn_debug (("MCORE: skipping to new address 0x%x\n", addr)); - mcore_insn_debug (("MCORE: continuing\n")); - continue; - } - - /* None of these instructions are prologue, so don't touch - anything. */ - mcore_insn_debug (("MCORE: no subu r1,r0, NOT altering framesize.\n")); - break; - } - - /* This is not a prologue insn, so stop here. */ - mcore_insn_debug (("MCORE: insn is not a prologue insn -- ending scan\n")); - break; - } - - mcore_insn_debug (("MCORE: done analyzing prologue\n")); - mcore_insn_debug (("MCORE: prologue end = 0x%x\n", addr)); - - /* Save everything we have learned about this frame into FI. */ - if (fi != NULL) - { - fi->extra_info->framesize = framesize; - fi->extra_info->fp_regnum = fp_regnum; - fi->extra_info->status = flags; - - /* Fix the frame pointer. When gcc uses r8 as a frame pointer, - it is really an arg ptr. We adjust fi->frame to be a "real" - frame pointer. */ - if (fi->next == NULL) - { - if (fi->extra_info->status & MY_FRAME_IN_SP) - fi->frame = read_sp () + framesize; - else - fi->frame = read_register (fp_regnum) + framesize; - } - - /* Note where saved registers are stored. The offsets in REGISTER_OFFSETS - are computed relative to the top of the frame. */ - for (rn = 0; rn < NUM_REGS; rn++) - { - if (register_offsets[rn] >= 0) - { - fi->saved_regs[rn] = fi->frame - register_offsets[rn]; - mcore_insn_debug (("Saved register %s stored at 0x%08x, value=0x%08x\n", - mcore_register_names[rn], fi->saved_regs[rn], - read_memory_integer (fi->saved_regs[rn], 4))); - } - } - } - - /* Return addr of first non-prologue insn. */ - return addr; -} - -/* 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. */ - -CORE_ADDR -mcore_frame_chain (struct frame_info * fi) -{ - struct frame_info *dummy; - CORE_ADDR callers_addr; - - /* Analyze the prologue of this function. */ - if (fi->extra_info->status == 0) - mcore_analyze_prologue (fi, 0, 0); - - /* If mcore_analyze_prologue set NO_MORE_FRAMES, quit now. */ - if (fi->extra_info->status & NO_MORE_FRAMES) - return 0; - - /* Now that we've analyzed our prologue, we can start to ask - for information about our caller. The easiest way to do - this is to analyze our caller's prologue. - - If our caller has a frame pointer, then we need to find - the value of that register upon entry to our frame. - This value is either in fi->saved_regs[rn] if it's saved, - or it's still in a register. - - If our caller does not have a frame pointer, then his frame base - is <our base> + -<caller's frame size>. */ - dummy = analyze_dummy_frame (FRAME_SAVED_PC (fi), fi->frame); - - if (dummy->extra_info->status & MY_FRAME_IN_FP) - { - int fp = dummy->extra_info->fp_regnum; - - /* Our caller has a frame pointer. */ - if (fi->saved_regs[fp] != 0) - { - /* The "FP" was saved on the stack. Don't forget to adjust - the "FP" with the framesize to get a real FP. */ - callers_addr = read_memory_integer (fi->saved_regs[fp], REGISTER_SIZE) - + dummy->extra_info->framesize; - } - else - { - /* It's still in the register. Don't forget to adjust - the "FP" with the framesize to get a real FP. */ - callers_addr = read_register (fp) + dummy->extra_info->framesize; - } - } - else - { - /* Our caller does not have a frame pointer. */ - callers_addr = fi->frame + dummy->extra_info->framesize; - } - - return callers_addr; -} - -/* Skip the prologue of the function at PC. */ - -CORE_ADDR -mcore_skip_prologue (CORE_ADDR pc) -{ - CORE_ADDR func_addr, func_end; - struct symtab_and_line sal; - - /* If we have line debugging information, then the end of the - prologue should be the first assembly instruction of the first - source line */ - if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) - { - sal = find_pc_line (func_addr, 0); - if (sal.end && sal.end < func_end) - return sal.end; - } - - return mcore_analyze_prologue (NULL, pc, 1); -} - -/* Return the address at which function arguments are offset. */ -CORE_ADDR -mcore_frame_args_address (struct frame_info * fi) -{ - return fi->frame - fi->extra_info->framesize; -} - -CORE_ADDR -mcore_frame_locals_address (struct frame_info * fi) -{ - return fi->frame - fi->extra_info->framesize; -} - -/* Return the frame pointer in use at address PC. */ - -void -mcore_virtual_frame_pointer (CORE_ADDR pc, int *reg, LONGEST *offset) -{ - struct frame_info *dummy = analyze_dummy_frame (pc, 0); - if (dummy->extra_info->status & MY_FRAME_IN_SP) - { - *reg = SP_REGNUM; - *offset = 0; - } - else - { - *reg = dummy->extra_info->fp_regnum; - *offset = 0; - } -} - -/* Find the value of register REGNUM in frame FI. */ - -CORE_ADDR -mcore_find_callers_reg (struct frame_info *fi, int regnum) -{ - for (; fi != NULL; 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->saved_regs[regnum] != 0) - return read_memory_integer (fi->saved_regs[regnum], - REGISTER_SIZE); - } - - return read_register (regnum); -} - -/* Find the saved pc in frame FI. */ - -CORE_ADDR -mcore_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 mcore_find_callers_reg (fi, PR_REGNUM); -} - -/* INFERIOR FUNCTION CALLS */ - -/* This routine gets called when either the user uses the "return" - command, or the call dummy breakpoint gets hit. */ - -void -mcore_pop_frame (struct frame_info *fi) -{ - int rn; - - if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) - generic_pop_dummy_frame (); - else - { - /* Write out the PC we saved. */ - write_register (PC_REGNUM, FRAME_SAVED_PC (fi)); - - /* Restore any saved registers. */ - for (rn = 0; rn < NUM_REGS; rn++) - { - if (fi->saved_regs[rn] != 0) - { - ULONGEST value; - - value = read_memory_unsigned_integer (fi->saved_regs[rn], - REGISTER_SIZE); - write_register (rn, value); - } - } - - /* Actually cut back the stack. */ - write_register (SP_REGNUM, FRAME_FP (fi)); - } - - /* Finally, throw away any cached frame information. */ - flush_cached_frames (); -} - -/* Setup arguments and PR for a call to the target. First six arguments - go in FIRST_ARGREG -> LAST_ARGREG, subsequent args go on to the stack. - - * Types with lengths greater than REGISTER_SIZE may not be split - between registers and the stack, and they must start in an even-numbered - register. Subsequent args will go onto the stack. - - * Structs may be split between registers and stack, left-aligned. - - * If the function returns a struct which will not fit into registers (it's - more than eight bytes), we must allocate for that, too. Gdb will tell - us where this buffer is (STRUCT_ADDR), and we simply place it into - FIRST_ARGREG, since the MCORE treats struct returns (of less than eight - bytes) as hidden first arguments. */ - -CORE_ADDR -mcore_push_arguments (int nargs, struct value **args, CORE_ADDR sp, - unsigned char struct_return, CORE_ADDR struct_addr) -{ - int argreg; - int argnum; - struct stack_arg - { - int len; - char *val; - } - *stack_args; - int nstack_args = 0; - - stack_args = (struct stack_arg *) alloca (nargs * sizeof (struct stack_arg)); - - argreg = FIRST_ARGREG; - - /* Align the stack. This is mostly a nop, but not always. It will be needed - if we call a function which has argument overflow. */ - sp &= ~3; - - /* If this function returns a struct which does not fit in the - return registers, we must pass a buffer to the function - which it can use to save the return value. */ - if (struct_return) - write_register (argreg++, struct_addr); - - /* FIXME: what about unions? */ - for (argnum = 0; argnum < nargs; argnum++) - { - char *val = (char *) VALUE_CONTENTS (args[argnum]); - int len = TYPE_LENGTH (VALUE_TYPE (args[argnum])); - struct type *type = VALUE_TYPE (args[argnum]); - int olen; - - mcore_insn_debug (("MCORE PUSH: argreg=%d; len=%d; %s\n", - argreg, len, TYPE_CODE (type) == TYPE_CODE_STRUCT ? "struct" : "not struct")); - /* Arguments larger than a register must start in an even - numbered register. */ - olen = len; - - if (TYPE_CODE (type) != TYPE_CODE_STRUCT && len > REGISTER_SIZE && argreg % 2) - { - mcore_insn_debug (("MCORE PUSH: %d > REGISTER_SIZE: and %s is not even\n", - len, mcore_register_names[argreg])); - argreg++; - } - - if ((argreg <= LAST_ARGREG && len <= (LAST_ARGREG - argreg + 1) * REGISTER_SIZE) - || (TYPE_CODE (type) == TYPE_CODE_STRUCT)) - { - /* Something that will fit entirely into registers (or a struct - which may be split between registers and stack). */ - mcore_insn_debug (("MCORE PUSH: arg %d going into regs\n", argnum)); - - if (TYPE_CODE (type) == TYPE_CODE_STRUCT && olen < REGISTER_SIZE) - { - /* Small structs must be right aligned within the register, - the most significant bits are undefined. */ - write_register (argreg, extract_unsigned_integer (val, len)); - argreg++; - len = 0; - } - - while (len > 0 && argreg <= LAST_ARGREG) - { - write_register (argreg, extract_unsigned_integer (val, REGISTER_SIZE)); - argreg++; - val += REGISTER_SIZE; - len -= REGISTER_SIZE; - } - - /* Any remainder for the stack is noted below... */ - } - else if (TYPE_CODE (VALUE_TYPE (args[argnum])) != TYPE_CODE_STRUCT - && len > REGISTER_SIZE) - { - /* All subsequent args go onto the stack. */ - mcore_insn_debug (("MCORE PUSH: does not fit into regs, going onto stack\n")); - argnum = LAST_ARGREG + 1; - } - - if (len > 0) - { - /* Note that this must be saved onto the stack */ - mcore_insn_debug (("MCORE PUSH: adding arg %d to stack\n", argnum)); - stack_args[nstack_args].val = val; - stack_args[nstack_args].len = len; - nstack_args++; - } - - } - - /* We're done with registers and stack allocation. Now do the actual - stack pushes. */ - while (nstack_args--) - { - sp -= stack_args[nstack_args].len; - write_memory (sp, stack_args[nstack_args].val, stack_args[nstack_args].len); - } - - /* Return adjusted stack pointer. */ - return sp; -} - -/* Store the return address for the call dummy. For MCore, we've - opted to use generic call dummies, so we simply store the - CALL_DUMMY_ADDRESS into the PR register (r15). */ - -CORE_ADDR -mcore_push_return_address (CORE_ADDR pc, CORE_ADDR sp) -{ - write_register (PR_REGNUM, CALL_DUMMY_ADDRESS ()); - return sp; -} - -/* Setting/getting return values from functions. - - The Motorola MCore processors use r2/r3 to return anything - not larger than 32 bits. Everything else goes into a caller- - supplied buffer, which is passed in via a hidden first - argument. - - For gdb, this leaves us two routes, based on what - USE_STRUCT_CONVENTION (mcore_use_struct_convention) returns. - If this macro returns 1, gdb will call STORE_STRUCT_RETURN and - EXTRACT_STRUCT_VALUE_ADDRESS. - - If USE_STRUCT_CONVENTION retruns 0, then gdb uses STORE_RETURN_VALUE - and EXTRACT_RETURN_VALUE to store/fetch the functions return value. */ - -/* Should we use EXTRACT_STRUCT_VALUE_ADDRESS instead of - EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc - and TYPE is the type (which is known to be struct, union or array). */ - -int -mcore_use_struct_convention (int gcc_p, struct type *type) -{ - return (TYPE_LENGTH (type) > 8); -} - -/* Where is the return value saved? For MCore, a pointer to - this buffer was passed as a hidden first argument, so - just return that address. */ - -CORE_ADDR -mcore_extract_struct_value_address (char *regbuf) -{ - return extract_address (regbuf + REGISTER_BYTE (FIRST_ARGREG), REGISTER_SIZE); -} - -/* Given a function which returns a value of type TYPE, extract the - the function's return value and place the result into VALBUF. - REGBUF is the register contents of the target. */ - -void -mcore_extract_return_value (struct type *type, char *regbuf, char *valbuf) -{ - /* Copy the return value (starting) in RETVAL_REGNUM to VALBUF. */ - /* Only getting the first byte! if len = 1, we need the last byte of - the register, not the first. */ - memcpy (valbuf, regbuf + REGISTER_BYTE (RETVAL_REGNUM) + - (TYPE_LENGTH (type) < 4 ? 4 - TYPE_LENGTH (type) : 0), TYPE_LENGTH (type)); -} - -/* Store the return value in VALBUF (of type TYPE) where the caller - expects to see it. - - Values less than 32 bits are stored in r2, right justified and - sign or zero extended. - - Values between 32 and 64 bits are stored in r2 (most - significant word) and r3 (least significant word, left justified). - Note that this includes structures of less than eight bytes, too. */ - -void -mcore_store_return_value (struct type *type, char *valbuf) -{ - int value_size; - int return_size; - int offset; - char *zeros; - - value_size = TYPE_LENGTH (type); - - /* Return value fits into registers. */ - return_size = (value_size + REGISTER_SIZE - 1) & ~(REGISTER_SIZE - 1); - offset = REGISTER_BYTE (RETVAL_REGNUM) + (return_size - value_size); - zeros = alloca (return_size); - memset (zeros, 0, return_size); - - write_register_bytes (REGISTER_BYTE (RETVAL_REGNUM), zeros, return_size); - write_register_bytes (offset, valbuf, value_size); -} - -/* Initialize our target-dependent "stuff" for this newly created frame. - - This includes allocating space for saved registers and analyzing - the prologue of this frame. */ - -void -mcore_init_extra_frame_info (struct frame_info *fi) -{ - if (fi->next) - fi->pc = FRAME_SAVED_PC (fi->next); - - frame_saved_regs_zalloc (fi); - - fi->extra_info = (struct frame_extra_info *) - frame_obstack_alloc (sizeof (struct frame_extra_info)); - fi->extra_info->status = 0; - fi->extra_info->framesize = 0; - - 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); - } - else - mcore_analyze_prologue (fi, 0, 0); -} - -/* Get an insturction from memory. */ - -static int -get_insn (CORE_ADDR pc) -{ - char buf[4]; - int status = read_memory_nobpt (pc, buf, 2); - if (status != 0) - return 0; - - return extract_unsigned_integer (buf, 2); -} - -void -_initialize_mcore_tdep (void) -{ - extern int print_insn_mcore (bfd_vma, disassemble_info *); - tm_print_insn = print_insn_mcore; - -#ifdef MCORE_DEBUG - add_show_from_set (add_set_cmd ("mcoredebug", no_class, - var_boolean, (char *) &mcore_debug, - "Set mcore debugging.\n", &setlist), - &showlist); -#endif -} |