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author | K. Richard Pixley <rich@cygnus> | 1991-03-28 16:28:29 +0000 |
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committer | K. Richard Pixley <rich@cygnus> | 1991-03-28 16:28:29 +0000 |
commit | dd3b648e8b12ceb7bfce66e7f179b671403aea9c (patch) | |
tree | 91119a0f4943acc9293cd8baba06943621b6e6c7 /gdb/m68k-pinsn.c | |
parent | bd5635a1e2b38ee8432fcdaa6456079191375277 (diff) | |
download | gdb-dd3b648e8b12ceb7bfce66e7f179b671403aea9c.zip gdb-dd3b648e8b12ceb7bfce66e7f179b671403aea9c.tar.gz gdb-dd3b648e8b12ceb7bfce66e7f179b671403aea9c.tar.bz2 |
Johns release
Diffstat (limited to 'gdb/m68k-pinsn.c')
-rw-r--r-- | gdb/m68k-pinsn.c | 774 |
1 files changed, 774 insertions, 0 deletions
diff --git a/gdb/m68k-pinsn.c b/gdb/m68k-pinsn.c new file mode 100644 index 0000000..608bc25 --- /dev/null +++ b/gdb/m68k-pinsn.c @@ -0,0 +1,774 @@ +/* Print m68k instructions for GDB, the GNU debugger. + Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc. + +This file is part of GDB. + +GDB 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 1, or (at your option) +any later version. + +GDB 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 GDB; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <stdio.h> + +#include "defs.h" +#include "param.h" +#include "symtab.h" +#include "m68k-opcode.h" +#include "gdbcore.h" + +/* 68k instructions are never longer than this many bytes. */ +#define MAXLEN 22 + +/* Number of elements in the opcode table. */ +#define NOPCODES (sizeof m68k_opcodes / sizeof m68k_opcodes[0]) + +extern char *reg_names[]; +char *fpcr_names[] = { "", "fpiar", "fpsr", "fpiar/fpsr", "fpcr", + "fpiar/fpcr", "fpsr/fpcr", "fpiar-fpcr"}; + +static unsigned char *print_insn_arg (); +static unsigned char *print_indexed (); +static void print_base (); +static int fetch_arg (); + +#define NEXTBYTE(p) (p += 2, ((char *)p)[-1]) + +#define NEXTWORD(p) \ + (p += 2, ((((char *)p)[-2]) << 8) + p[-1]) + +#define NEXTLONG(p) \ + (p += 4, (((((p[-4] << 8) + p[-3]) << 8) + p[-2]) << 8) + p[-1]) + +#define NEXTSINGLE(p) \ + (p += 4, *((float *)(p - 4))) + +#define NEXTDOUBLE(p) \ + (p += 8, *((double *)(p - 8))) + +#define NEXTEXTEND(p) \ + (p += 12, 0.0) /* Need a function to convert from extended to double + precision... */ + +#define NEXTPACKED(p) \ + (p += 12, 0.0) /* Need a function to convert from packed to double + precision. Actually, it's easier to print a + packed number than a double anyway, so maybe + there should be a special case to handle this... */ + +/* Print the m68k instruction at address MEMADDR in debugged memory, + on STREAM. Returns length of the instruction, in bytes. */ + +int +print_insn (memaddr, stream) + CORE_ADDR memaddr; + FILE *stream; +{ + unsigned char buffer[MAXLEN]; + register int i; + register unsigned char *p; + register char *d; + register int bestmask; + int best; + + read_memory (memaddr, buffer, MAXLEN); + + bestmask = 0; + best = -1; + for (i = 0; i < NOPCODES; i++) + { + register unsigned int opcode = m68k_opcodes[i].opcode; + register unsigned int match = m68k_opcodes[i].match; + if (((0xff & buffer[0] & (match >> 24)) == (0xff & (opcode >> 24))) + && ((0xff & buffer[1] & (match >> 16)) == (0xff & (opcode >> 16))) + && ((0xff & buffer[2] & (match >> 8)) == (0xff & (opcode >> 8))) + && ((0xff & buffer[3] & match) == (0xff & opcode))) + { + /* Don't use for printout the variants of divul and divsl + that have the same register number in two places. + The more general variants will match instead. */ + for (d = m68k_opcodes[i].args; *d; d += 2) + if (d[1] == 'D') + break; + + /* Don't use for printout the variants of most floating + point coprocessor instructions which use the same + register number in two places, as above. */ + if (*d == 0) + for (d = m68k_opcodes[i].args; *d; d += 2) + if (d[1] == 't') + break; + + if (*d == 0 && match > bestmask) + { + best = i; + bestmask = match; + } + } + } + + /* Handle undefined instructions. */ + if (best < 0) + { + fprintf_filtered (stream, "0%o", (buffer[0] << 8) + buffer[1]); + return 2; + } + + fprintf_filtered (stream, "%s", m68k_opcodes[best].name); + + /* Point at first word of argument data, + and at descriptor for first argument. */ + p = buffer + 2; + + /* Why do this this way? -MelloN */ + for (d = m68k_opcodes[best].args; *d; d += 2) + { + if (d[0] == '#') + { + if (d[1] == 'l' && p - buffer < 6) + p = buffer + 6; + else if (p - buffer < 4 && d[1] != 'C' && d[1] != '8' ) + p = buffer + 4; + } + if (d[1] >= '1' && d[1] <= '3' && p - buffer < 4) + p = buffer + 4; + if (d[1] >= '4' && d[1] <= '6' && p - buffer < 6) + p = buffer + 6; + if ((d[0] == 'L' || d[0] == 'l') && d[1] == 'w' && p - buffer < 4) + p = buffer + 4; + } + + d = m68k_opcodes[best].args; + + if (*d) + fputs_filtered (" ", stream); + + while (*d) + { + p = print_insn_arg (d, buffer, p, memaddr + p - buffer, stream); + d += 2; + if (*d && *(d - 2) != 'I' && *d != 'k') + fputs_filtered (",", stream); + } + return p - buffer; +} + +static unsigned char * +print_insn_arg (d, buffer, p, addr, stream) + char *d; + unsigned char *buffer; + register unsigned char *p; + CORE_ADDR addr; /* PC for this arg to be relative to */ + FILE *stream; +{ + register int val; + register int place = d[1]; + int regno; + register char *regname; + register unsigned char *p1; + register double flval; + int flt_p; + + switch (*d) + { + case 'C': + fprintf_filtered (stream, "ccr"); + break; + + case 'S': + fprintf_filtered (stream, "sr"); + break; + + case 'U': + fprintf_filtered (stream, "usp"); + break; + + case 'J': + { + static struct { char *name; int value; } names[] + = {{"sfc", 0x000}, {"dfc", 0x001}, {"cacr", 0x002}, + {"usp", 0x800}, {"vbr", 0x801}, {"caar", 0x802}, + {"msp", 0x803}, {"isp", 0x804}}; + + val = fetch_arg (buffer, place, 12); + for (regno = sizeof names / sizeof names[0] - 1; regno >= 0; regno--) + if (names[regno].value == val) + { + fprintf_filtered (stream, names[regno].name); + break; + } + if (regno < 0) + fprintf_filtered (stream, "%d", val); + } + break; + + case 'Q': + val = fetch_arg (buffer, place, 3); + /* 0 means 8, except for the bkpt instruction... */ + if (val == 0 && d[1] != 's') + val = 8; + fprintf_filtered (stream, "#%d", val); + break; + + case 'M': + val = fetch_arg (buffer, place, 8); + if (val & 0x80) + val = val - 0x100; + fprintf_filtered (stream, "#%d", val); + break; + + case 'T': + val = fetch_arg (buffer, place, 4); + fprintf_filtered (stream, "#%d", val); + break; + + case 'D': + fprintf_filtered (stream, "%s", reg_names[fetch_arg (buffer, place, 3)]); + break; + + case 'A': + fprintf_filtered (stream, "%s", + reg_names[fetch_arg (buffer, place, 3) + 010]); + break; + + case 'R': + fprintf_filtered (stream, "%s", reg_names[fetch_arg (buffer, place, 4)]); + break; + + case 'F': + fprintf_filtered (stream, "fp%d", fetch_arg (buffer, place, 3)); + break; + + case 'O': + val = fetch_arg (buffer, place, 6); + if (val & 0x20) + fprintf_filtered (stream, "%s", reg_names [val & 7]); + else + fprintf_filtered (stream, "%d", val); + break; + + case '+': + fprintf_filtered (stream, "%s@+", + reg_names[fetch_arg (buffer, place, 3) + 8]); + break; + + case '-': + fprintf_filtered (stream, "%s@-", + reg_names[fetch_arg (buffer, place, 3) + 8]); + break; + + case 'k': + if (place == 'k') + fprintf_filtered (stream, "{%s}", reg_names[fetch_arg (buffer, place, 3)]); + else if (place == 'C') + { + val = fetch_arg (buffer, place, 7); + if ( val > 63 ) /* This is a signed constant. */ + val -= 128; + fprintf_filtered (stream, "{#%d}", val); + } + else + error ("Invalid arg format in opcode table: \"%c%c\".", + *d, place); + break; + + case '#': + case '^': + p1 = buffer + (*d == '#' ? 2 : 4); + if (place == 's') + val = fetch_arg (buffer, place, 4); + else if (place == 'C') + val = fetch_arg (buffer, place, 7); + else if (place == '8') + val = fetch_arg (buffer, place, 3); + else if (place == '3') + val = fetch_arg (buffer, place, 8); + else if (place == 'b') + val = NEXTBYTE (p1); + else if (place == 'w') + val = NEXTWORD (p1); + else if (place == 'l') + val = NEXTLONG (p1); + else + error ("Invalid arg format in opcode table: \"%c%c\".", + *d, place); + fprintf_filtered (stream, "#%d", val); + break; + + case 'B': + if (place == 'b') + val = NEXTBYTE (p); + else if (place == 'w') + val = NEXTWORD (p); + else if (place == 'l') + val = NEXTLONG (p); + else if (place == 'g') + { + val = ((char *)buffer)[1]; + if (val == 0) + val = NEXTWORD (p); + else if (val == -1) + val = NEXTLONG (p); + } + else if (place == 'c') + { + if (buffer[1] & 0x40) /* If bit six is one, long offset */ + val = NEXTLONG (p); + else + val = NEXTWORD (p); + } + else + error ("Invalid arg format in opcode table: \"%c%c\".", + *d, place); + + print_address (addr + val, stream); + break; + + case 'd': + val = NEXTWORD (p); + fprintf_filtered (stream, "%s@(%d)", + reg_names[fetch_arg (buffer, place, 3)], val); + break; + + case 's': + fprintf_filtered (stream, "%s", + fpcr_names[fetch_arg (buffer, place, 3)]); + break; + + case 'I': + val = fetch_arg (buffer, 'd', 3); /* Get coprocessor ID... */ + if (val != 1) /* Unusual coprocessor ID? */ + fprintf_filtered (stream, "(cpid=%d) ", val); + if (place == 'i') + p += 2; /* Skip coprocessor extended operands */ + break; + + case '*': + case '~': + case '%': + case ';': + case '@': + case '!': + case '$': + case '?': + case '/': + case '&': + + if (place == 'd') + { + val = fetch_arg (buffer, 'x', 6); + val = ((val & 7) << 3) + ((val >> 3) & 7); + } + else + val = fetch_arg (buffer, 's', 6); + + /* Get register number assuming address register. */ + regno = (val & 7) + 8; + regname = reg_names[regno]; + switch (val >> 3) + { + case 0: + fprintf_filtered (stream, "%s", reg_names[val]); + break; + + case 1: + fprintf_filtered (stream, "%s", regname); + break; + + case 2: + fprintf_filtered (stream, "%s@", regname); + break; + + case 3: + fprintf_filtered (stream, "%s@+", regname); + break; + + case 4: + fprintf_filtered (stream, "%s@-", regname); + break; + + case 5: + val = NEXTWORD (p); + fprintf_filtered (stream, "%s@(%d)", regname, val); + break; + + case 6: + p = print_indexed (regno, p, addr, stream); + break; + + case 7: + switch (val & 7) + { + case 0: + val = NEXTWORD (p); + fprintf_filtered (stream, "@#"); + print_address (val, stream); + break; + + case 1: + val = NEXTLONG (p); + fprintf_filtered (stream, "@#"); + print_address (val, stream); + break; + + case 2: + val = NEXTWORD (p); + print_address (addr + val, stream); + break; + + case 3: + p = print_indexed (-1, p, addr, stream); + break; + + case 4: + flt_p = 1; /* Assume it's a float... */ + switch( place ) + { + case 'b': + val = NEXTBYTE (p); + flt_p = 0; + break; + + case 'w': + val = NEXTWORD (p); + flt_p = 0; + break; + + case 'l': + val = NEXTLONG (p); + flt_p = 0; + break; + + case 'f': + flval = NEXTSINGLE(p); + break; + + case 'F': + flval = NEXTDOUBLE(p); + break; + + case 'x': + flval = NEXTEXTEND(p); + break; + + case 'p': + flval = NEXTPACKED(p); + break; + + default: + error ("Invalid arg format in opcode table: \"%c%c\".", + *d, place); + } + if ( flt_p ) /* Print a float? */ + fprintf_filtered (stream, "#%g", flval); + else + fprintf_filtered (stream, "#%d", val); + break; + + default: + fprintf_filtered (stream, "<invalid address mode 0%o>", val); + } + } + break; + + case 'L': + case 'l': + if (place == 'w') + { + char doneany; + p1 = buffer + 2; + val = NEXTWORD (p1); + /* Move the pointer ahead if this point is farther ahead + than the last. */ + p = p1 > p ? p1 : p; + if (val == 0) + { + fputs_filtered ("#0", stream); + break; + } + if (*d == 'l') + { + register int newval = 0; + for (regno = 0; regno < 16; ++regno) + if (val & (0x8000 >> regno)) + newval |= 1 << regno; + val = newval; + } + val &= 0xffff; + doneany = 0; + for (regno = 0; regno < 16; ++regno) + if (val & (1 << regno)) + { + int first_regno; + if (doneany) + fputs_filtered ("/", stream); + doneany = 1; + fprintf_filtered (stream, "%s", reg_names[regno]); + first_regno = regno; + while (val & (1 << (regno + 1))) + ++regno; + if (regno > first_regno) + fprintf_filtered (stream, "-%s", reg_names[regno]); + } + } + else if (place == '3') + { + /* `fmovem' insn. */ + char doneany; + val = fetch_arg (buffer, place, 8); + if (val == 0) + { + fputs_filtered ("#0", stream); + break; + } + if (*d == 'l') + { + register int newval = 0; + for (regno = 0; regno < 8; ++regno) + if (val & (0x80 >> regno)) + newval |= 1 << regno; + val = newval; + } + val &= 0xff; + doneany = 0; + for (regno = 0; regno < 8; ++regno) + if (val & (1 << regno)) + { + int first_regno; + if (doneany) + fputs_filtered ("/", stream); + doneany = 1; + fprintf_filtered (stream, "fp%d", regno); + first_regno = regno; + while (val & (1 << (regno + 1))) + ++regno; + if (regno > first_regno) + fprintf_filtered (stream, "-fp%d", regno); + } + } + else + abort (); + break; + + default: + error ("Invalid arg format in opcode table: \"%c\".", *d); + } + + return (unsigned char *) p; +} + +/* Fetch BITS bits from a position in the instruction specified by CODE. + CODE is a "place to put an argument", or 'x' for a destination + that is a general address (mode and register). + BUFFER contains the instruction. */ + +static int +fetch_arg (buffer, code, bits) + unsigned char *buffer; + char code; + int bits; +{ + register int val; + switch (code) + { + case 's': + val = buffer[1]; + break; + + case 'd': /* Destination, for register or quick. */ + val = (buffer[0] << 8) + buffer[1]; + val >>= 9; + break; + + case 'x': /* Destination, for general arg */ + val = (buffer[0] << 8) + buffer[1]; + val >>= 6; + break; + + case 'k': + val = (buffer[3] >> 4); + break; + + case 'C': + val = buffer[3]; + break; + + case '1': + val = (buffer[2] << 8) + buffer[3]; + val >>= 12; + break; + + case '2': + val = (buffer[2] << 8) + buffer[3]; + val >>= 6; + break; + + case '3': + case 'j': + val = (buffer[2] << 8) + buffer[3]; + break; + + case '4': + val = (buffer[4] << 8) + buffer[5]; + val >>= 12; + break; + + case '5': + val = (buffer[4] << 8) + buffer[5]; + val >>= 6; + break; + + case '6': + val = (buffer[4] << 8) + buffer[5]; + break; + + case '7': + val = (buffer[2] << 8) + buffer[3]; + val >>= 7; + break; + + case '8': + val = (buffer[2] << 8) + buffer[3]; + val >>= 10; + break; + + default: + abort (); + } + + switch (bits) + { + case 3: + return val & 7; + case 4: + return val & 017; + case 5: + return val & 037; + case 6: + return val & 077; + case 7: + return val & 0177; + case 8: + return val & 0377; + case 12: + return val & 07777; + default: + abort (); + } +} + +/* Print an indexed argument. The base register is BASEREG (-1 for pc). + P points to extension word, in buffer. + ADDR is the nominal core address of that extension word. */ + +static unsigned char * +print_indexed (basereg, p, addr, stream) + int basereg; + unsigned char *p; + FILE *stream; + CORE_ADDR addr; +{ + register int word; + static char *scales[] = {"", "*2", "*4", "*8"}; + register int base_disp; + register int outer_disp; + char buf[40]; + + word = NEXTWORD (p); + + /* Generate the text for the index register. + Where this will be output is not yet determined. */ + sprintf (buf, "[%s.%c%s]", + reg_names[(word >> 12) & 0xf], + (word & 0x800) ? 'l' : 'w', + scales[(word >> 9) & 3]); + + /* Handle the 68000 style of indexing. */ + + if ((word & 0x100) == 0) + { + print_base (basereg, + ((word & 0x80) ? word | 0xff00 : word & 0xff) + + ((basereg == -1) ? addr : 0), + stream); + fputs_filtered (buf, stream); + return p; + } + + /* Handle the generalized kind. */ + /* First, compute the displacement to add to the base register. */ + + if (word & 0200) + basereg = -2; + if (word & 0100) + buf[0] = 0; + base_disp = 0; + switch ((word >> 4) & 3) + { + case 2: + base_disp = NEXTWORD (p); + break; + case 3: + base_disp = NEXTLONG (p); + } + if (basereg == -1) + base_disp += addr; + + /* Handle single-level case (not indirect) */ + + if ((word & 7) == 0) + { + print_base (basereg, base_disp, stream); + fputs_filtered (buf, stream); + return p; + } + + /* Two level. Compute displacement to add after indirection. */ + + outer_disp = 0; + switch (word & 3) + { + case 2: + outer_disp = NEXTWORD (p); + break; + case 3: + outer_disp = NEXTLONG (p); + } + + fprintf_filtered (stream, "%d(", outer_disp); + print_base (basereg, base_disp, stream); + + /* If postindexed, print the closeparen before the index. */ + if (word & 4) + fprintf_filtered (stream, ")%s", buf); + /* If preindexed, print the closeparen after the index. */ + else + fprintf_filtered (stream, "%s)", buf); + + return p; +} + +/* Print a base register REGNO and displacement DISP, on STREAM. + REGNO = -1 for pc, -2 for none (suppressed). */ + +static void +print_base (regno, disp, stream) + int regno; + int disp; + FILE *stream; +{ + if (regno == -2) + fprintf_filtered (stream, "%d", disp); + else if (regno == -1) + fprintf_filtered (stream, "0x%x", disp); + else + fprintf_filtered (stream, "%d(%s)", disp, reg_names[regno]); +} |