| /* Target-machine dependent code for Motorola MCore for GDB, the GNU debugger |
| |
| Copyright 1999, 2000, 2001, 2002, 2003, 2004 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 "objfiles.h" |
| #include "gdbcore.h" |
| #include "inferior.h" |
| #include "arch-utils.h" |
| #include "gdb_string.h" |
| #include "disasm.h" |
| #include "dis-asm.h" |
| |
| static CORE_ADDR mcore_analyze_prologue (struct frame_info *fi, CORE_ADDR pc, |
| int skip_prologue); |
| static int get_insn (CORE_ADDR pc); |
| |
| #ifdef MCORE_DEBUG |
| int mcore_debug = 0; |
| #endif |
| |
| |
| /* All registers are 4 bytes long. */ |
| #define MCORE_REG_SIZE 4 |
| #define MCORE_NUM_REGS 65 |
| |
| /* Some useful register numbers. */ |
| #define PR_REGNUM 15 |
| #define FIRST_ARGREG 2 |
| #define LAST_ARGREG 7 |
| #define RETVAL_REGNUM 2 |
| |
| |
| /* 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); |
| gdb_print_insn (pc, gdb_stdout); |
| 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 |
| |
| |
| static struct type * |
| mcore_register_virtual_type (int regnum) |
| { |
| if (regnum < 0 || regnum >= MCORE_NUM_REGS) |
| internal_error (__FILE__, __LINE__, |
| "mcore_register_virtual_type: illegal register number %d", |
| regnum); |
| else |
| return builtin_type_int; |
| } |
| |
| static int |
| mcore_register_byte (int regnum) |
| { |
| if (regnum < 0 || regnum >= MCORE_NUM_REGS) |
| internal_error (__FILE__, __LINE__, |
| "mcore_register_byte: illegal register number %d", |
| regnum); |
| else |
| return (regnum * MCORE_REG_SIZE); |
| } |
| |
| static int |
| mcore_register_size (int regnum) |
| { |
| |
| if (regnum < 0 || regnum >= MCORE_NUM_REGS) |
| internal_error (__FILE__, __LINE__, |
| "mcore_register_size: illegal register number %d", |
| regnum); |
| else |
| return MCORE_REG_SIZE; |
| } |
| |
| /* The registers of the Motorola MCore processors */ |
| |
| static const char * |
| mcore_register_name (int regnum) |
| { |
| |
| static char *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" |
| }; |
| |
| if (regnum < 0 || |
| regnum >= sizeof (register_names) / sizeof (register_names[0])) |
| internal_error (__FILE__, __LINE__, |
| "mcore_register_name: illegal register number %d", |
| regnum); |
| else |
| return register_names[regnum]; |
| } |
| |
| /* 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 */ |
| |
| static const unsigned char * |
| mcore_breakpoint_from_pc (CORE_ADDR * bp_addr, int *bp_size) |
| { |
| static char breakpoint[] = |
| {0x00, 0x00}; |
| *bp_size = 2; |
| return breakpoint; |
| } |
| |
| static CORE_ADDR |
| mcore_saved_pc_after_call (struct frame_info *frame) |
| { |
| return read_register (PR_REGNUM); |
| } |
| |
| /* This is currently handled by init_extra_frame_info. */ |
| static void |
| mcore_frame_init_saved_regs (struct frame_info *frame) |
| { |
| |
| } |
| |
| /* This is currently handled by mcore_push_arguments */ |
| static void |
| mcore_store_struct_return (CORE_ADDR addr, CORE_ADDR sp) |
| { |
| |
| } |
| |
| static int |
| mcore_reg_struct_has_addr (int gcc_p, struct type *type) |
| { |
| return 0; |
| } |
| |
| |
| /* 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) |
| { |
| struct cleanup *old_chain = make_cleanup (null_cleanup, NULL); |
| struct frame_info *dummy |
| = deprecated_frame_xmalloc_with_cleanup (SIZEOF_FRAME_SAVED_REGS, |
| sizeof (struct frame_extra_info)); |
| deprecated_update_frame_pc_hack (dummy, pc); |
| deprecated_update_frame_base_hack (dummy, frame); |
| get_frame_extra_info (dummy)->status = 0; |
| get_frame_extra_info (dummy)->framesize = 0; |
| mcore_analyze_prologue (dummy, 0, 0); |
| do_cleanups (old_chain); |
| 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 : get_frame_pc (fi)); |
| |
| /* 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) |
| get_frame_extra_info (fi)->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 (get_next_frame (fi) == NULL) |
| deprecated_update_frame_base_hack (fi, read_sp ()); |
| return get_frame_pc (fi); |
| } |
| |
| /* Check for first insn of prologue */ |
| if (fi != NULL && get_frame_pc (fi) == func_addr) |
| { |
| if (get_next_frame (fi) == NULL) |
| deprecated_update_frame_base_hack (fi, read_sp ()); |
| return get_frame_pc (fi); |
| } |
| |
| /* Figure out where to stop scanning */ |
| stop = (fi ? get_frame_pc (fi) : 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) |
| { |
| get_frame_extra_info (fi)->framesize = framesize; |
| get_frame_extra_info (fi)->fp_regnum = fp_regnum; |
| get_frame_extra_info (fi)->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 (get_next_frame (fi) == NULL) |
| { |
| if (get_frame_extra_info (fi)->status & MY_FRAME_IN_SP) |
| deprecated_update_frame_base_hack (fi, read_sp () + framesize); |
| else |
| deprecated_update_frame_base_hack (fi, 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) |
| { |
| deprecated_get_frame_saved_regs (fi)[rn] = get_frame_base (fi) - 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 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC |
| will be called for the new frame. */ |
| |
| static CORE_ADDR |
| mcore_frame_chain (struct frame_info * fi) |
| { |
| struct frame_info *dummy; |
| CORE_ADDR callers_addr; |
| |
| /* Analyze the prologue of this function. */ |
| if (get_frame_extra_info (fi)->status == 0) |
| mcore_analyze_prologue (fi, 0, 0); |
| |
| /* If mcore_analyze_prologue set NO_MORE_FRAMES, quit now. */ |
| if (get_frame_extra_info (fi)->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 (DEPRECATED_FRAME_SAVED_PC (fi), get_frame_base (fi)); |
| |
| if (get_frame_extra_info (dummy)->status & MY_FRAME_IN_FP) |
| { |
| int fp = get_frame_extra_info (dummy)->fp_regnum; |
| |
| /* Our caller has a frame pointer. */ |
| if (deprecated_get_frame_saved_regs (fi)[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 (deprecated_get_frame_saved_regs (fi)[fp], |
| DEPRECATED_REGISTER_SIZE) |
| + get_frame_extra_info (dummy)->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) + get_frame_extra_info (dummy)->framesize; |
| } |
| } |
| else |
| { |
| /* Our caller does not have a frame pointer. */ |
| callers_addr = get_frame_base (fi) + get_frame_extra_info (dummy)->framesize; |
| } |
| |
| return callers_addr; |
| } |
| |
| /* Skip the prologue of the function at PC. */ |
| |
| static 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. */ |
| static CORE_ADDR |
| mcore_frame_args_address (struct frame_info * fi) |
| { |
| return get_frame_base (fi) - get_frame_extra_info (fi)->framesize; |
| } |
| |
| static CORE_ADDR |
| mcore_frame_locals_address (struct frame_info * fi) |
| { |
| return get_frame_base (fi) - get_frame_extra_info (fi)->framesize; |
| } |
| |
| /* Return the frame pointer in use at address PC. */ |
| |
| static void |
| mcore_virtual_frame_pointer (CORE_ADDR pc, int *reg, LONGEST *offset) |
| { |
| struct frame_info *dummy = analyze_dummy_frame (pc, 0); |
| if (get_frame_extra_info (dummy)->status & MY_FRAME_IN_SP) |
| { |
| *reg = SP_REGNUM; |
| *offset = 0; |
| } |
| else |
| { |
| *reg = get_frame_extra_info (dummy)->fp_regnum; |
| *offset = 0; |
| } |
| } |
| |
| /* Find the value of register REGNUM in frame FI. */ |
| |
| static CORE_ADDR |
| mcore_find_callers_reg (struct frame_info *fi, int regnum) |
| { |
| for (; fi != NULL; fi = get_next_frame (fi)) |
| { |
| if (deprecated_pc_in_call_dummy (get_frame_pc (fi))) |
| return deprecated_read_register_dummy (get_frame_pc (fi), |
| get_frame_base (fi), regnum); |
| else if (deprecated_get_frame_saved_regs (fi)[regnum] != 0) |
| return read_memory_integer (deprecated_get_frame_saved_regs (fi)[regnum], |
| DEPRECATED_REGISTER_SIZE); |
| } |
| |
| return read_register (regnum); |
| } |
| |
| /* Find the saved pc in frame FI. */ |
| |
| static CORE_ADDR |
| mcore_frame_saved_pc (struct frame_info * fi) |
| { |
| |
| if (deprecated_pc_in_call_dummy (get_frame_pc (fi))) |
| return deprecated_read_register_dummy (get_frame_pc (fi), |
| get_frame_base (fi), 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. */ |
| |
| static void |
| mcore_pop_frame (void) |
| { |
| int rn; |
| struct frame_info *fi = get_current_frame (); |
| |
| if (deprecated_pc_in_call_dummy (get_frame_pc (fi))) |
| deprecated_pop_dummy_frame (); |
| else |
| { |
| /* Write out the PC we saved. */ |
| write_register (PC_REGNUM, DEPRECATED_FRAME_SAVED_PC (fi)); |
| |
| /* Restore any saved registers. */ |
| for (rn = 0; rn < NUM_REGS; rn++) |
| { |
| if (deprecated_get_frame_saved_regs (fi)[rn] != 0) |
| { |
| ULONGEST value; |
| |
| value = read_memory_unsigned_integer (deprecated_get_frame_saved_regs (fi)[rn], |
| DEPRECATED_REGISTER_SIZE); |
| write_register (rn, value); |
| } |
| } |
| |
| /* Actually cut back the stack. */ |
| write_register (SP_REGNUM, get_frame_base (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 DEPRECATED_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. */ |
| |
| static CORE_ADDR |
| mcore_push_arguments (int nargs, struct value **args, CORE_ADDR sp, |
| int 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 > DEPRECATED_REGISTER_SIZE && argreg % 2) |
| { |
| mcore_insn_debug (("MCORE PUSH: %d > DEPRECATED_REGISTER_SIZE: and %s is not even\n", |
| len, mcore_register_names[argreg])); |
| argreg++; |
| } |
| |
| if ((argreg <= LAST_ARGREG && len <= (LAST_ARGREG - argreg + 1) * DEPRECATED_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 < DEPRECATED_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, DEPRECATED_REGISTER_SIZE)); |
| argreg++; |
| val += DEPRECATED_REGISTER_SIZE; |
| len -= DEPRECATED_REGISTER_SIZE; |
| } |
| |
| /* Any remainder for the stack is noted below... */ |
| } |
| else if (TYPE_CODE (VALUE_TYPE (args[argnum])) != TYPE_CODE_STRUCT |
| && len > DEPRECATED_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 entry-point |
| address into the PR register (r15). */ |
| |
| static CORE_ADDR |
| mcore_push_return_address (CORE_ADDR pc, CORE_ADDR sp) |
| { |
| write_register (PR_REGNUM, entry_point_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 |
| DEPRECATED_USE_STRUCT_CONVENTION (mcore_use_struct_convention) |
| returns. If this macro returns 1, gdb will call |
| STORE_STRUCT_RETURN to store the return value. |
| |
| If DEPRECATED_USE_STRUCT_CONVENTION returns 0, then gdb uses |
| STORE_RETURN_VALUE and EXTRACT_RETURN_VALUE to store/fetch the |
| functions return value. */ |
| |
| static int |
| mcore_use_struct_convention (int gcc_p, struct type *type) |
| { |
| return (TYPE_LENGTH (type) > 8); |
| } |
| |
| /* 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. */ |
| |
| static 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 + DEPRECATED_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. */ |
| |
| static 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 + DEPRECATED_REGISTER_SIZE - 1) & ~(DEPRECATED_REGISTER_SIZE - 1); |
| offset = DEPRECATED_REGISTER_BYTE (RETVAL_REGNUM) + (return_size - value_size); |
| zeros = alloca (return_size); |
| memset (zeros, 0, return_size); |
| |
| deprecated_write_register_bytes (DEPRECATED_REGISTER_BYTE (RETVAL_REGNUM), zeros, |
| return_size); |
| deprecated_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. */ |
| |
| static void |
| mcore_init_extra_frame_info (int fromleaf, struct frame_info *fi) |
| { |
| if (fi && get_next_frame (fi)) |
| deprecated_update_frame_pc_hack (fi, DEPRECATED_FRAME_SAVED_PC (get_next_frame (fi))); |
| |
| frame_saved_regs_zalloc (fi); |
| |
| frame_extra_info_zalloc (fi, sizeof (struct frame_extra_info)); |
| get_frame_extra_info (fi)->status = 0; |
| get_frame_extra_info (fi)->framesize = 0; |
| |
| if (deprecated_pc_in_call_dummy (get_frame_pc (fi))) |
| { |
| /* We need to setup fi->frame here because call_function_by_hand |
| gets it wrong by assuming it's always FP. */ |
| deprecated_update_frame_base_hack (fi, deprecated_read_register_dummy (get_frame_pc (fi), get_frame_base (fi), 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); |
| } |
| |
| static struct gdbarch * |
| mcore_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| { |
| struct gdbarch_tdep *tdep = NULL; |
| struct gdbarch *gdbarch; |
| |
| /* find a candidate among the list of pre-declared architectures. */ |
| arches = gdbarch_list_lookup_by_info (arches, &info); |
| if (arches != NULL) |
| return (arches->gdbarch); |
| |
| gdbarch = gdbarch_alloc (&info, 0); |
| |
| /* NOTE: cagney/2002-12-06: This can be deleted when this arch is |
| ready to unwind the PC first (see frame.c:get_prev_frame()). */ |
| set_gdbarch_deprecated_init_frame_pc (gdbarch, deprecated_init_frame_pc_default); |
| |
| /* Registers: */ |
| |
| /* All registers are 32 bits */ |
| set_gdbarch_deprecated_register_size (gdbarch, MCORE_REG_SIZE); |
| set_gdbarch_register_name (gdbarch, mcore_register_name); |
| set_gdbarch_deprecated_register_virtual_type (gdbarch, mcore_register_virtual_type); |
| set_gdbarch_deprecated_register_virtual_size (gdbarch, mcore_register_size); |
| set_gdbarch_deprecated_register_raw_size (gdbarch, mcore_register_size); |
| set_gdbarch_deprecated_register_byte (gdbarch, mcore_register_byte); |
| set_gdbarch_deprecated_register_bytes (gdbarch, MCORE_REG_SIZE * MCORE_NUM_REGS); |
| set_gdbarch_num_regs (gdbarch, MCORE_NUM_REGS); |
| set_gdbarch_pc_regnum (gdbarch, 64); |
| set_gdbarch_sp_regnum (gdbarch, 0); |
| set_gdbarch_deprecated_fp_regnum (gdbarch, 0); |
| |
| /* Call Dummies: */ |
| |
| set_gdbarch_deprecated_saved_pc_after_call (gdbarch, mcore_saved_pc_after_call); |
| set_gdbarch_breakpoint_from_pc (gdbarch, mcore_breakpoint_from_pc); |
| set_gdbarch_deprecated_push_return_address (gdbarch, mcore_push_return_address); |
| set_gdbarch_deprecated_push_arguments (gdbarch, mcore_push_arguments); |
| |
| /* Frames: */ |
| |
| set_gdbarch_deprecated_init_extra_frame_info (gdbarch, mcore_init_extra_frame_info); |
| set_gdbarch_deprecated_frame_chain (gdbarch, mcore_frame_chain); |
| set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, mcore_frame_init_saved_regs); |
| set_gdbarch_deprecated_frame_saved_pc (gdbarch, mcore_frame_saved_pc); |
| set_gdbarch_deprecated_store_return_value (gdbarch, mcore_store_return_value); |
| set_gdbarch_deprecated_extract_return_value (gdbarch, |
| mcore_extract_return_value); |
| set_gdbarch_deprecated_store_struct_return (gdbarch, mcore_store_struct_return); |
| set_gdbarch_skip_prologue (gdbarch, mcore_skip_prologue); |
| set_gdbarch_deprecated_frame_args_address (gdbarch, mcore_frame_args_address); |
| set_gdbarch_deprecated_frame_locals_address (gdbarch, mcore_frame_locals_address); |
| set_gdbarch_deprecated_pop_frame (gdbarch, mcore_pop_frame); |
| set_gdbarch_virtual_frame_pointer (gdbarch, mcore_virtual_frame_pointer); |
| |
| /* Misc.: */ |
| |
| /* Stack grows down. */ |
| set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| set_gdbarch_deprecated_use_struct_convention (gdbarch, mcore_use_struct_convention); |
| set_gdbarch_believe_pcc_promotion (gdbarch, 1); |
| /* MCore will never pass a sturcture by reference. It will always be split |
| between registers and stack. */ |
| set_gdbarch_deprecated_reg_struct_has_addr |
| (gdbarch, mcore_reg_struct_has_addr); |
| |
| /* Should be using push_dummy_call. */ |
| set_gdbarch_deprecated_dummy_write_sp (gdbarch, deprecated_write_sp); |
| |
| set_gdbarch_print_insn (gdbarch, print_insn_mcore); |
| |
| return gdbarch; |
| } |
| |
| static void |
| mcore_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file) |
| { |
| |
| } |
| |
| extern initialize_file_ftype _initialize_mcore_tdep; /* -Wmissing-prototypes */ |
| |
| void |
| _initialize_mcore_tdep (void) |
| { |
| gdbarch_register (bfd_arch_mcore, mcore_gdbarch_init, mcore_dump_tdep); |
| |
| #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 |
| } |