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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/i960-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/i960-tdep.c')
-rw-r--r-- | gdb/i960-tdep.c | 838 |
1 files changed, 0 insertions, 838 deletions
diff --git a/gdb/i960-tdep.c b/gdb/i960-tdep.c deleted file mode 100644 index e33415d..0000000 --- a/gdb/i960-tdep.c +++ /dev/null @@ -1,838 +0,0 @@ -/* Target-machine dependent code for the Intel 960 - Copyright 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. - Contributed by Intel Corporation. - examine_prologue and other parts contributed by Wind River Systems. - -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 "symtab.h" -#include "value.h" -#include "frame.h" -#include "floatformat.h" -#include "target.h" -#include "gdbcore.h" - -static CORE_ADDR next_insn PARAMS ((CORE_ADDR memaddr, - unsigned int *pword1, - unsigned int *pword2)); - -/* Does the specified function use the "struct returning" convention - or the "value returning" convention? The "value returning" convention - almost invariably returns the entire value in registers. The - "struct returning" convention often returns the entire value in - memory, and passes a pointer (out of or into the function) saying - where the value (is or should go). - - Since this sometimes depends on whether it was compiled with GCC, - this is also an argument. This is used in call_function to build a - stack, and in value_being_returned to print return values. - - On i960, a structure is returned in registers g0-g3, if it will fit. - If it's more than 16 bytes long, g13 pointed to it on entry. */ - -int -i960_use_struct_convention (gcc_p, type) - int gcc_p; - struct type *type; -{ - return (TYPE_LENGTH (type) > 16); -} - -/* gdb960 is always running on a non-960 host. Check its characteristics. - This routine must be called as part of gdb initialization. */ - -static void -check_host() -{ - int i; - - static struct typestruct { - int hostsize; /* Size of type on host */ - int i960size; /* Size of type on i960 */ - char *typename; /* Name of type, for error msg */ - } types[] = { - { sizeof(short), 2, "short" }, - { sizeof(int), 4, "int" }, - { sizeof(long), 4, "long" }, - { sizeof(float), 4, "float" }, - { sizeof(double), 8, "double" }, - { sizeof(char *), 4, "pointer" }, - }; -#define TYPELEN (sizeof(types) / sizeof(struct typestruct)) - - /* Make sure that host type sizes are same as i960 - */ - for ( i = 0; i < TYPELEN; i++ ){ - if ( types[i].hostsize != types[i].i960size ){ - printf_unfiltered("sizeof(%s) != %d: PROCEED AT YOUR OWN RISK!\n", - types[i].typename, types[i].i960size ); - } - - } -} - -/* Examine an i960 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 gcc960 1.21, particularly - the routine i960_function_prologue (). A "regular expression" for - the function prologue is given below: - - (lda LRn, g14 - mov g14, g[0-7] - (mov 0, g14) | (lda 0, g14))? - - (mov[qtl]? g[0-15], r[4-15])* - ((addo [1-31], sp, sp) | (lda n(sp), sp))? - (st[qtl]? g[0-15], n(fp))* - - (cmpobne 0, g14, LFn - mov sp, g14 - lda 0x30(sp), sp - LFn: stq g0, (g14) - stq g4, 0x10(g14) - stq g8, 0x20(g14))? - - (st g14, n(fp))? - (mov g13,r[4-15])? -*/ - -/* Macros for extracting fields from i960 instructions. */ - -#define BITMASK(pos, width) (((0x1 << (width)) - 1) << (pos)) -#define EXTRACT_FIELD(val, pos, width) ((val) >> (pos) & BITMASK (0, width)) - -#define REG_SRC1(insn) EXTRACT_FIELD (insn, 0, 5) -#define REG_SRC2(insn) EXTRACT_FIELD (insn, 14, 5) -#define REG_SRCDST(insn) EXTRACT_FIELD (insn, 19, 5) -#define MEM_SRCDST(insn) EXTRACT_FIELD (insn, 19, 5) -#define MEMA_OFFSET(insn) EXTRACT_FIELD (insn, 0, 12) - -/* 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, and (for two-word instructions), *PWORD2 receives - the second. */ - -#define NEXT_PROLOGUE_INSN(addr, lim, pword1, pword2) \ - (((addr) < (lim)) ? next_insn (addr, pword1, pword2) : 0) - -static CORE_ADDR -examine_prologue (ip, limit, frame_addr, fsr) - register CORE_ADDR ip; - register CORE_ADDR limit; - CORE_ADDR frame_addr; - struct frame_saved_regs *fsr; -{ - register CORE_ADDR next_ip; - register int src, dst; - register unsigned int *pcode; - unsigned int insn1, insn2; - int size; - int within_leaf_prologue; - CORE_ADDR save_addr; - static unsigned int varargs_prologue_code [] = - { - 0x3507a00c, /* cmpobne 0x0, g14, LFn */ - 0x5cf01601, /* mov sp, g14 */ - 0x8c086030, /* lda 0x30(sp), sp */ - 0xb2879000, /* LFn: stq g0, (g14) */ - 0xb2a7a010, /* stq g4, 0x10(g14) */ - 0xb2c7a020 /* stq g8, 0x20(g14) */ - }; - - /* Accept a leaf procedure prologue code fragment if present. - Note that ip might point to either the leaf or non-leaf - entry point; we look for the non-leaf entry point first: */ - - within_leaf_prologue = 0; - if ((next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2)) - && ((insn1 & 0xfffff000) == 0x8cf00000 /* lda LRx, g14 (MEMA) */ - || (insn1 & 0xfffffc60) == 0x8cf03000)) /* lda LRx, g14 (MEMB) */ - { - within_leaf_prologue = 1; - next_ip = NEXT_PROLOGUE_INSN (next_ip, limit, &insn1, &insn2); - } - - /* Now look for the prologue code at a leaf entry point: */ - - if (next_ip - && (insn1 & 0xff87ffff) == 0x5c80161e /* mov g14, gx */ - && REG_SRCDST (insn1) <= G0_REGNUM + 7) - { - within_leaf_prologue = 1; - if ((next_ip = NEXT_PROLOGUE_INSN (next_ip, limit, &insn1, &insn2)) - && (insn1 == 0x8cf00000 /* lda 0, g14 */ - || insn1 == 0x5cf01e00)) /* mov 0, g14 */ - { - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - within_leaf_prologue = 0; - } - } - - /* If something that looks like the beginning of a leaf prologue - has been seen, but the remainder of the prologue is missing, bail. - We don't know what we've got. */ - - if (within_leaf_prologue) - return (ip); - - /* Accept zero or more instances of "mov[qtl]? gx, ry", where y >= 4. - This may cause us to mistake the moving of a register - parameter to a local register for the saving of a callee-saved - register, but that can't be helped, since with the - "-fcall-saved" flag, any register can be made callee-saved. */ - - while (next_ip - && (insn1 & 0xfc802fb0) == 0x5c000610 - && (dst = REG_SRCDST (insn1)) >= (R0_REGNUM + 4)) - { - src = REG_SRC1 (insn1); - size = EXTRACT_FIELD (insn1, 24, 2) + 1; - save_addr = frame_addr + ((dst - R0_REGNUM) * 4); - while (size--) - { - fsr->regs[src++] = save_addr; - save_addr += 4; - } - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - } - - /* Accept an optional "addo n, sp, sp" or "lda n(sp), sp". */ - - if (next_ip && - ((insn1 & 0xffffffe0) == 0x59084800 /* addo n, sp, sp */ - || (insn1 & 0xfffff000) == 0x8c086000 /* lda n(sp), sp (MEMA) */ - || (insn1 & 0xfffffc60) == 0x8c087400)) /* lda n(sp), sp (MEMB) */ - { - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - } - - /* Accept zero or more instances of "st[qtl]? gx, n(fp)". - This may cause us to mistake the copying of a register - parameter to the frame for the saving of a callee-saved - register, but that can't be helped, since with the - "-fcall-saved" flag, any register can be made callee-saved. - We can, however, refuse to accept a save of register g14, - since that is matched explicitly below. */ - - while (next_ip && - ((insn1 & 0xf787f000) == 0x9287e000 /* stl? gx, n(fp) (MEMA) */ - || (insn1 & 0xf787fc60) == 0x9287f400 /* stl? gx, n(fp) (MEMB) */ - || (insn1 & 0xef87f000) == 0xa287e000 /* st[tq] gx, n(fp) (MEMA) */ - || (insn1 & 0xef87fc60) == 0xa287f400) /* st[tq] gx, n(fp) (MEMB) */ - && ((src = MEM_SRCDST (insn1)) != G14_REGNUM)) - { - save_addr = frame_addr + ((insn1 & BITMASK (12, 1)) - ? insn2 : MEMA_OFFSET (insn1)); - size = (insn1 & BITMASK (29, 1)) ? ((insn1 & BITMASK (28, 1)) ? 4 : 3) - : ((insn1 & BITMASK (27, 1)) ? 2 : 1); - while (size--) - { - fsr->regs[src++] = save_addr; - save_addr += 4; - } - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - } - - /* Accept the varargs prologue code if present. */ - - size = sizeof (varargs_prologue_code) / sizeof (int); - pcode = varargs_prologue_code; - while (size-- && next_ip && *pcode++ == insn1) - { - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - } - - /* Accept an optional "st g14, n(fp)". */ - - if (next_ip && - ((insn1 & 0xfffff000) == 0x92f7e000 /* st g14, n(fp) (MEMA) */ - || (insn1 & 0xfffffc60) == 0x92f7f400)) /* st g14, n(fp) (MEMB) */ - { - fsr->regs[G14_REGNUM] = frame_addr + ((insn1 & BITMASK (12, 1)) - ? insn2 : MEMA_OFFSET (insn1)); - ip = next_ip; - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); - } - - /* Accept zero or one instance of "mov g13, ry", where y >= 4. - This is saving the address where a struct should be returned. */ - - if (next_ip - && (insn1 & 0xff802fbf) == 0x5c00061d - && (dst = REG_SRCDST (insn1)) >= (R0_REGNUM + 4)) - { - save_addr = frame_addr + ((dst - R0_REGNUM) * 4); - fsr->regs[G0_REGNUM+13] = save_addr; - ip = next_ip; -#if 0 /* We'll need this once there is a subsequent instruction examined. */ - next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn1, &insn2); -#endif - } - - 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)); -} - -/* 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 CORE_ADDR next_addr; - register CORE_ADDR *saved_regs; - register int regnum; - 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. */ - - ip = get_pc_function_start (fi->pc); - sal = find_pc_line (ip, 0); - limit = (sal.end && sal.end < fi->pc) ? sal.end: fi->pc; - - examine_prologue (ip, limit, fi->frame, cache_fsr); - - /* Record the addresses at which the local registers are saved. - Strictly speaking, we should only do this for non-leaf procedures, - but no one will ever look at these values if it is a leaf procedure, - since local registers are always caller-saved. */ - - next_addr = (CORE_ADDR) fi->frame; - saved_regs = cache_fsr->regs; - for (regnum = R0_REGNUM; regnum <= R15_REGNUM; regnum++) - { - *saved_regs++ = next_addr; - next_addr += 4; - } - - cache_fsr->regs[FP_REGNUM] = cache_fsr->regs[PFP_REGNUM]; - } - - *fsr = *fi->fsr; - - /* Fetch the value of the sp from memory every time, since it - is conceivable that it has changed since the cache was flushed. - This unfortunately undoes much of the savings from caching the - saved register values. I suggest adding an argument to - get_frame_saved_regs () specifying the register number we're - interested in (or -1 for all registers). This would be passed - through to FRAME_FIND_SAVED_REGS (), permitting more efficient - computation of saved register addresses (e.g., on the i960, - we don't have to examine the prologue to find local registers). - -- markf@wrs.com - FIXME, we don't need to refetch this, since the cache is cleared - every time the child process is restarted. If GDB itself - modifies SP, it has to clear the cache by hand (does it?). -gnu */ - - fsr->regs[SP_REGNUM] = read_memory_integer (fsr->regs[SP_REGNUM], 4); -} - -/* 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, must_be_correct) - struct frame_info *fi; -{ - struct frame_saved_regs fsr; - CORE_ADDR ap; - - /* If g14 was saved in the frame by the function prologue code, return - the saved value. If the frame is current and we are being sloppy, - return the value of g14. Otherwise, return zero. */ - - get_frame_saved_regs (fi, &fsr); - if (fsr.regs[G14_REGNUM]) - ap = read_memory_integer (fsr.regs[G14_REGNUM],4); - else - { - if (must_be_correct) - return 0; /* Don't cache this result */ - if (get_next_frame (fi)) - ap = 0; - else - ap = read_register (G14_REGNUM); - if (ap == 0) - ap = fi->frame; - } - fi->arg_pointer = ap; /* Cache it for next time */ - return ap; -} - -/* Return the address of the return struct for the frame - described by FI. Returns 0 if the address is unknown. */ - -CORE_ADDR -frame_struct_result_address (fi) - struct frame_info *fi; -{ - struct frame_saved_regs fsr; - CORE_ADDR ap; - - /* If the frame is non-current, check to see if g14 was saved in the - frame by the function prologue code; return the saved value if so, - zero otherwise. If the frame is current, return the value of g14. - - FIXME, shouldn't this use the saved value as long as we are past - the function prologue, and only use the current value if we have - no saved value and are at TOS? -- gnu@cygnus.com */ - - if (get_next_frame (fi)) - { - get_frame_saved_regs (fi, &fsr); - if (fsr.regs[G13_REGNUM]) - ap = read_memory_integer (fsr.regs[G13_REGNUM],4); - else - ap = 0; - } - else - ap = read_register (G13_REGNUM); - - return ap; -} - -/* Return address to which the currently executing leafproc will return, - or 0 if ip is not in a leafproc (or if we can't tell if it is). - - Do this by finding the starting address of the routine in which ip lies. - If the instruction there is "mov g14, gx" (where x is in [0,7]), this - is a leafproc and the return address is in register gx. Well, this is - true unless the return address points at a RET instruction in the current - procedure, which indicates that we have a 'dual entry' routine that - has been entered through the CALL entry point. */ - -CORE_ADDR -leafproc_return (ip) - CORE_ADDR ip; /* ip from currently executing function */ -{ - register struct minimal_symbol *msymbol; - char *p; - int dst; - unsigned int insn1, insn2; - CORE_ADDR return_addr; - - if ((msymbol = lookup_minimal_symbol_by_pc (ip)) != NULL) - { - if ((p = strchr(SYMBOL_NAME (msymbol), '.')) && STREQ (p, ".lf")) - { - if (next_insn (SYMBOL_VALUE_ADDRESS (msymbol), &insn1, &insn2) - && (insn1 & 0xff87ffff) == 0x5c80161e /* mov g14, gx */ - && (dst = REG_SRCDST (insn1)) <= G0_REGNUM + 7) - { - /* Get the return address. If the "mov g14, gx" - instruction hasn't been executed yet, read - the return address from g14; otherwise, read it - from the register into which g14 was moved. */ - - return_addr = - read_register ((ip == SYMBOL_VALUE_ADDRESS (msymbol)) - ? G14_REGNUM : dst); - - /* We know we are in a leaf procedure, but we don't know - whether the caller actually did a "bal" to the ".lf" - entry point, or a normal "call" to the non-leaf entry - point one instruction before. In the latter case, the - return address will be the address of a "ret" - instruction within the procedure itself. We test for - this below. */ - - if (!next_insn (return_addr, &insn1, &insn2) - || (insn1 & 0xff000000) != 0xa000000 /* ret */ - || lookup_minimal_symbol_by_pc (return_addr) != msymbol) - return (return_addr); - } - } - } - - return (0); -} - -/* Immediately after a function call, return the saved pc. - Can't go through the frames for this because on some machines - the new frame is not set up until the new function executes - some instructions. - On the i960, the frame *is* set up immediately after the call, - unless the function is a leaf procedure. */ - -CORE_ADDR -saved_pc_after_call (frame) - struct frame_info *frame; -{ - CORE_ADDR saved_pc; - - saved_pc = leafproc_return (get_frame_pc (frame)); - if (!saved_pc) - saved_pc = FRAME_SAVED_PC (frame); - - return saved_pc; -} - -/* Discard from the stack the innermost frame, - restoring all saved registers. */ - -void -pop_frame () -{ - register struct frame_info *current_fi, *prev_fi; - register int i; - CORE_ADDR save_addr; - CORE_ADDR leaf_return_addr; - struct frame_saved_regs fsr; - char local_regs_buf[16 * 4]; - - current_fi = get_current_frame (); - - /* First, undo what the hardware does when we return. - If this is a non-leaf procedure, restore local registers from - the save area in the calling frame. Otherwise, load the return - address obtained from leafproc_return () into the rip. */ - - leaf_return_addr = leafproc_return (current_fi->pc); - if (!leaf_return_addr) - { - /* Non-leaf procedure. Restore local registers, incl IP. */ - prev_fi = get_prev_frame (current_fi); - read_memory (prev_fi->frame, local_regs_buf, sizeof (local_regs_buf)); - write_register_bytes (REGISTER_BYTE (R0_REGNUM), local_regs_buf, - sizeof (local_regs_buf)); - - /* Restore frame pointer. */ - write_register (FP_REGNUM, prev_fi->frame); - } - else - { - /* Leaf procedure. Just restore the return address into the IP. */ - write_register (RIP_REGNUM, leaf_return_addr); - } - - /* Now restore any global regs that the current function had saved. */ - get_frame_saved_regs (current_fi, &fsr); - for (i = G0_REGNUM; i < G14_REGNUM; i++) - { - if (save_addr = fsr.regs[i]) - write_register (i, read_memory_integer (save_addr, 4)); - } - - /* Flush the frame cache, create a frame for the new innermost frame, - and make it the current frame. */ - - flush_cached_frames (); -} - -/* Given a 960 stop code (fault or trace), return the signal which - corresponds. */ - -enum target_signal -i960_fault_to_signal (fault) - int fault; -{ - switch (fault) - { - case 0: return TARGET_SIGNAL_BUS; /* parallel fault */ - case 1: return TARGET_SIGNAL_UNKNOWN; - case 2: return TARGET_SIGNAL_ILL; /* operation fault */ - case 3: return TARGET_SIGNAL_FPE; /* arithmetic fault */ - case 4: return TARGET_SIGNAL_FPE; /* floating point fault */ - - /* constraint fault. This appears not to distinguish between - a range constraint fault (which should be SIGFPE) and a privileged - fault (which should be SIGILL). */ - case 5: return TARGET_SIGNAL_ILL; - - case 6: return TARGET_SIGNAL_SEGV; /* virtual memory fault */ - - /* protection fault. This is for an out-of-range argument to - "calls". I guess it also could be SIGILL. */ - case 7: return TARGET_SIGNAL_SEGV; - - case 8: return TARGET_SIGNAL_BUS; /* machine fault */ - case 9: return TARGET_SIGNAL_BUS; /* structural fault */ - case 0xa: return TARGET_SIGNAL_ILL; /* type fault */ - case 0xb: return TARGET_SIGNAL_UNKNOWN; /* reserved fault */ - case 0xc: return TARGET_SIGNAL_BUS; /* process fault */ - case 0xd: return TARGET_SIGNAL_SEGV; /* descriptor fault */ - case 0xe: return TARGET_SIGNAL_BUS; /* event fault */ - case 0xf: return TARGET_SIGNAL_UNKNOWN; /* reserved fault */ - case 0x10: return TARGET_SIGNAL_TRAP; /* single-step trace */ - case 0x11: return TARGET_SIGNAL_TRAP; /* branch trace */ - case 0x12: return TARGET_SIGNAL_TRAP; /* call trace */ - case 0x13: return TARGET_SIGNAL_TRAP; /* return trace */ - case 0x14: return TARGET_SIGNAL_TRAP; /* pre-return trace */ - case 0x15: return TARGET_SIGNAL_TRAP; /* supervisor call trace */ - case 0x16: return TARGET_SIGNAL_TRAP; /* breakpoint trace */ - default: return TARGET_SIGNAL_UNKNOWN; - } -} - -/****************************************/ -/* MEM format */ -/****************************************/ - -struct tabent { - char *name; - char numops; -}; - -static int /* returns instruction length: 4 or 8 */ -mem( memaddr, word1, word2, noprint ) - unsigned long memaddr; - unsigned long word1, word2; - int noprint; /* If TRUE, return instruction length, but - don't output any text. */ -{ - int i, j; - int len; - int mode; - int offset; - const char *reg1, *reg2, *reg3; - - /* This lookup table is too sparse to make it worth typing in, but not - * so large as to make a sparse array necessary. We allocate the - * table at runtime, initialize all entries to empty, and copy the - * real ones in from an initialization table. - * - * NOTE: In this table, the meaning of 'numops' is: - * 1: single operand - * 2: 2 operands, load instruction - * -2: 2 operands, store instruction - */ - static struct tabent *mem_tab = NULL; -/* Opcodes of 0x8X, 9X, aX, bX, and cX must be in the table. */ -#define MEM_MIN 0x80 -#define MEM_MAX 0xcf -#define MEM_SIZ ((MEM_MAX-MEM_MIN+1) * sizeof(struct tabent)) - - static struct { int opcode; char *name; char numops; } mem_init[] = { - 0x80, "ldob", 2, - 0x82, "stob", -2, - 0x84, "bx", 1, - 0x85, "balx", 2, - 0x86, "callx", 1, - 0x88, "ldos", 2, - 0x8a, "stos", -2, - 0x8c, "lda", 2, - 0x90, "ld", 2, - 0x92, "st", -2, - 0x98, "ldl", 2, - 0x9a, "stl", -2, - 0xa0, "ldt", 2, - 0xa2, "stt", -2, - 0xb0, "ldq", 2, - 0xb2, "stq", -2, - 0xc0, "ldib", 2, - 0xc2, "stib", -2, - 0xc8, "ldis", 2, - 0xca, "stis", -2, - 0, NULL, 0 - }; - - if ( mem_tab == NULL ){ - mem_tab = (struct tabent *) xmalloc( MEM_SIZ ); - memset( mem_tab, '\0', MEM_SIZ ); - for ( i = 0; mem_init[i].opcode != 0; i++ ){ - j = mem_init[i].opcode - MEM_MIN; - mem_tab[j].name = mem_init[i].name; - mem_tab[j].numops = mem_init[i].numops; - } - } - - i = ((word1 >> 24) & 0xff) - MEM_MIN; - mode = (word1 >> 10) & 0xf; - - if ( (mem_tab[i].name != NULL) /* Valid instruction */ - && ((mode == 5) || (mode >=12)) ){ /* With 32-bit displacement */ - len = 8; - } else { - len = 4; - } - - if ( noprint ){ - return len; - } - abort (); -} - -/* Read the i960 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 first word of the instruction - is stored at 'pword1', and the second word, if any, is stored at - 'pword2'. */ - -static CORE_ADDR -next_insn (memaddr, pword1, pword2) - unsigned int *pword1, *pword2; - CORE_ADDR memaddr; -{ - int len; - char buf[8]; - - /* Read the two (potential) words of the instruction at once, - to eliminate the overhead of two calls to read_memory (). - FIXME: Loses if the first one is readable but the second is not - (e.g. last word of the segment). */ - - read_memory (memaddr, buf, 8); - *pword1 = extract_unsigned_integer (buf, 4); - *pword2 = extract_unsigned_integer (buf + 4, 4); - - /* Divide instruction set into classes based on high 4 bits of opcode*/ - - switch ((*pword1 >> 28) & 0xf) - { - case 0x0: - case 0x1: /* ctrl */ - - case 0x2: - case 0x3: /* cobr */ - - case 0x5: - case 0x6: - case 0x7: /* reg */ - len = 4; - break; - - case 0x8: - case 0x9: - case 0xa: - case 0xb: - case 0xc: - len = mem (memaddr, *pword1, *pword2, 1); - break; - - default: /* invalid instruction */ - len = 0; - break; - } - - if (len) - return memaddr + len; - else - return 0; -} - -/* 'start_frame' is a variable in the MON960 runtime startup routine - that contains the frame pointer of the 'start' routine (the routine - that calls 'main'). By reading its contents out of remote memory, - we can tell where the frame chain ends: backtraces should halt before - they display this frame. */ - -int -mon960_frame_chain_valid (chain, curframe) - CORE_ADDR chain; - struct frame_info *curframe; -{ - struct symbol *sym; - struct minimal_symbol *msymbol; - - /* crtmon960.o is an assembler module that is assumed to be linked - * first in an i80960 executable. It contains the true entry point; - * it performs startup up initialization and then calls 'main'. - * - * 'sf' is the name of a variable in crtmon960.o that is set - * during startup to the address of the first frame. - * - * 'a' is the address of that variable in 80960 memory. - */ - static char sf[] = "start_frame"; - CORE_ADDR a; - - - chain &= ~0x3f; /* Zero low 6 bits because previous frame pointers - contain return status info in them. */ - if ( chain == 0 ){ - return 0; - } - - sym = lookup_symbol(sf, 0, VAR_NAMESPACE, (int *)NULL, - (struct symtab **)NULL); - if ( sym != 0 ){ - a = SYMBOL_VALUE (sym); - } else { - msymbol = lookup_minimal_symbol (sf, NULL, NULL); - if (msymbol == NULL) - return 0; - a = SYMBOL_VALUE_ADDRESS (msymbol); - } - - return ( chain != read_memory_integer(a,4) ); -} - -void -_initialize_i960_tdep () -{ - check_host (); - - tm_print_insn = print_insn_i960; -} |