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author | Doug Evans <dje@google.com> | 1998-01-13 01:37:20 +0000 |
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committer | Doug Evans <dje@google.com> | 1998-01-13 01:37:20 +0000 |
commit | bfc10abe47d82b1c6d10070a69b5e6fc11f0d311 (patch) | |
tree | 3c00bb850781e23e6a169fe63e7be74d1fec4eec /opcodes/cgen-asm.in | |
parent | c062b1036fc459e1b4fe66c61ef3c916756706c9 (diff) | |
download | gdb-bfc10abe47d82b1c6d10070a69b5e6fc11f0d311.zip gdb-bfc10abe47d82b1c6d10070a69b5e6fc11f0d311.tar.gz gdb-bfc10abe47d82b1c6d10070a69b5e6fc11f0d311.tar.bz2 |
* Makefile.am: Add cgen support.
* Makefile.in: Regenerate.
* configure.in: Add cgen support.
* configure: Regenerate.
* aclocal.m4: Regenerate.
* cgen.sh, cgen-asm.in, cgen-dis.in: New files.
Diffstat (limited to 'opcodes/cgen-asm.in')
-rw-r--r-- | opcodes/cgen-asm.in | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/opcodes/cgen-asm.in b/opcodes/cgen-asm.in new file mode 100644 index 0000000..8a5099b --- /dev/null +++ b/opcodes/cgen-asm.in @@ -0,0 +1,394 @@ +/* Assembler interface for targets using CGEN. -*- C -*- + CGEN: Cpu tools GENerator + +This file is used to generate @arch@-asm.c. + +Copyright (C) 1996, 1997 Free Software Foundation, Inc. + +This file is part of the GNU Binutils and GDB, the GNU debugger. + +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, 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 "sysdep.h" +#include <ctype.h> +#include <stdio.h> +#include "ansidecl.h" +#include "bfd.h" +#include "@arch@-opc.h" + +/* ??? The layout of this stuff is still work in progress. + For speed in assembly/disassembly, we use inline functions. That of course + will only work for GCC. When this stuff is finished, we can decide whether + to keep the inline functions (and only get the performance increase when + compiled with GCC), or switch to macros, or use something else. +*/ + +static const char *parse_insn_normal + PARAMS ((const CGEN_INSN *, const char **, CGEN_FIELDS *)); +static void insert_insn_normal + PARAMS ((const CGEN_INSN *, CGEN_FIELDS *, cgen_insn_t *)); + +/* Default insertion routine. + + SHIFT is negative for left shifts, positive for right shifts. + All bits of VALUE to be inserted must be valid as we don't handle + signed vs unsigned shifts. + + ATTRS is a mask of the boolean attributes. We don't need any at the + moment, but for consistency with extract_normal we have them. */ + +/* FIXME: This duplicates functionality with bfd's howto table and + bfd_install_relocation. */ +/* FIXME: For architectures where insns can be representable as ints, + store insn in `field' struct and add registers, etc. while parsing. */ + +static CGEN_INLINE void +insert_normal (value, attrs, start, length, shift, total_length, buffer) + long value; + unsigned int attrs; + int start, length, shift, total_length; + char *buffer; +{ + bfd_vma x; + +#if 0 /*def CGEN_INT_INSN*/ + *buffer |= ((value & ((1 << length) - 1)) + << (total_length - (start + length))); +#else + switch (total_length) + { + case 8: + x = *(unsigned char *) buffer; + break; + case 16: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + x = bfd_getb16 (buffer); + else + x = bfd_getl16 (buffer); + break; + case 32: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + x = bfd_getb32 (buffer); + else + x = bfd_getl32 (buffer); + break; + default : + abort (); + } + + if (shift < 0) + value <<= -shift; + else + value >>= shift; + + x |= ((value & ((1 << length) - 1)) + << (total_length - (start + length))); + + switch (total_length) + { + case 8: + *buffer = value; + break; + case 16: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + bfd_putb16 (x, buffer); + else + bfd_putl16 (x, buffer); + break; + case 32: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + bfd_putb32 (x, buffer); + else + bfd_putl32 (x, buffer); + break; + default : + abort (); + } +#endif +} + +/* -- assembler routines inserted here */ + +/* Default insn parser. + + The syntax string is scanned and operands are parsed and stored in FIELDS. + Relocs are queued as we go via other callbacks. + + ??? Note that this is currently an all-or-nothing parser. If we fail to + parse the instruction, we return 0 and the caller will start over from + the beginning. Backtracking will be necessary in parsing subexpressions, + but that can be handled there. Not handling backtracking here may get + expensive in the case of the m68k. Deal with later. + + Returns NULL for success, an error message for failure. +*/ + +static const char * +parse_insn_normal (insn, strp, fields) + const CGEN_INSN *insn; + const char **strp; + CGEN_FIELDS *fields; +{ + const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn); + const char *str = *strp; + const char *errmsg; + const char *p; + const unsigned char *syn; +#ifdef CGEN_MNEMONIC_OPERANDS + int past_opcode_p; +#endif + + /* For now we assume the mnemonic is first (there are no leading operands). + We can parse it without needing to set up operand parsing. */ + p = CGEN_INSN_MNEMONIC (insn); + while (*p && *p == *str) + ++p, ++str; + if (*p || (*str && !isspace (*str))) + return "unrecognized instruction"; + + CGEN_INIT_PARSE (); + cgen_init_parse_operand (); +#ifdef CGEN_MNEMONIC_OPERANDS + past_opcode_p = 0; +#endif + + /* We don't check for (*str != '\0') here because we want to parse + any trailing fake arguments in the syntax string. */ + syn = CGEN_SYNTAX_STRING (CGEN_INSN_SYNTAX (insn)); + /* Mnemonics come first for now, ensure valid string. */ + if (! CGEN_SYNTAX_MNEMONIC_P (*syn)) + abort (); + ++syn; + while (*syn != 0) + { + /* Non operand chars must match exactly. */ + /* FIXME: Need to better handle whitespace. */ + if (CGEN_SYNTAX_CHAR_P (*syn)) + { + if (*str == CGEN_SYNTAX_CHAR (*syn)) + { +#ifdef CGEN_MNEMONIC_OPERANDS + if (*syn == ' ') + past_opcode_p = 1; +#endif + ++syn; + ++str; + } + else + { + /* Syntax char didn't match. Can't be this insn. */ + /* FIXME: would like to return "expected char `c'" */ + return "syntax error"; + } + continue; + } + + /* We have an operand of some sort. */ + errmsg = @arch@_cgen_parse_operand (CGEN_SYNTAX_FIELD (*syn), + &str, fields); + if (errmsg) + return errmsg; + + /* Done with this operand, continue with next one. */ + ++syn; + } + + /* If we're at the end of the syntax string, we're done. */ + if (*syn == '\0') + { + /* FIXME: For the moment we assume a valid `str' can only contain + blanks now. IE: We needn't try again with a longer version of + the insn and it is assumed that longer versions of insns appear + before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3). */ + while (isspace (*str)) + ++str; + + if (*str != '\0') + return "junk at end of line"; /* FIXME: would like to include `str' */ + + return NULL; + } + + /* We couldn't parse it. */ + return "unrecognized instruction"; +} + +/* Default insn builder (insert handler). + The instruction is recorded in target byte order. */ + +static void +insert_insn_normal (insn, fields, buffer) + const CGEN_INSN *insn; + CGEN_FIELDS *fields; + cgen_insn_t *buffer; +{ + const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn); + bfd_vma value; + const unsigned char *syn; + + CGEN_INIT_INSERT (); + value = CGEN_INSN_VALUE (insn); + + /* If we're recording insns as numbers (rather than a string of bytes), + target byte order handling is deferred until later. */ +#undef min +#define min(a,b) ((a) < (b) ? (a) : (b)) +#if 0 /*def CGEN_INT_INSN*/ + *buffer = value; +#else + switch (min (CGEN_BASE_INSN_BITSIZE, CGEN_FIELDS_BITSIZE (fields))) + { + case 8: + *buffer = value; + break; + case 16: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + bfd_putb16 (value, (char *) buffer); + else + bfd_putl16 (value, (char *) buffer); + break; + case 32: + if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG) + bfd_putb32 (value, (char *) buffer); + else + bfd_putl32 (value, (char *) buffer); + break; + default: + abort (); + } +#endif + + /* ??? Rather than scanning the syntax string again, we could store + in `fields' a null terminated list of the fields that are present. */ + + for (syn = CGEN_SYNTAX_STRING (syntax); *syn != '\0'; ++syn) + { + if (CGEN_SYNTAX_CHAR_P (*syn)) + continue; + + @arch@_cgen_insert_operand (CGEN_SYNTAX_FIELD (*syn), fields, buffer); + } +} + +/* Main entry point. + This routine is called for each instruction to be assembled. + STR points to the insn to be assembled. + We assume all necessary tables have been initialized. + The result is a pointer to the insn's entry in the opcode table, + or NULL if an error occured (an error message will have already been + printed). */ + +const CGEN_INSN * +@arch@_cgen_assemble_insn (str, fields, buf, errmsg) + const char *str; + CGEN_FIELDS *fields; + cgen_insn_t *buf; + char **errmsg; +{ + const char *start; + CGEN_INSN_LIST *ilist; + + /* Skip leading white space. */ + while (isspace (*str)) + ++str; + + /* The instructions are stored in hashed lists. + Get the first in the list. */ + ilist = CGEN_ASM_LOOKUP_INSN (str); + + /* Keep looking until we find a match. */ + + start = str; + for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist)) + { + const CGEN_INSN *insn = ilist->insn; + +#if 0 /* not needed as unsupported opcodes shouldn't be in the hash lists */ + /* Is this insn supported by the selected cpu? */ + if (! @arch@_cgen_insn_supported (insn)) + continue; +#endif + +#if 1 /* FIXME: wip */ + /* If the RELAX attribute is set, this is an insn that shouldn't be + chosen immediately. Instead, it is used during assembler/linker + relaxation if possible. */ + if (CGEN_INSN_ATTR (insn, CGEN_INSN_RELAX) != 0) + continue; +#endif + + str = start; + + /* Record a default length for the insn. This will get set to the + correct value while parsing. */ + /* FIXME: wip */ + CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn); + + /* ??? The extent to which moving the parse and insert handlers into + this function (thus removing the function call) will speed things up + is unclear. The simplicity and flexibility of the current scheme is + appropriate for now. One could have the best of both worlds with + inline functions but of course that would only work for gcc. Since + we're machine generating some code we could do that here too. Maybe + later. */ + if (! (*CGEN_PARSE_FN (insn)) (insn, &str, fields)) + { + (*CGEN_INSERT_FN (insn)) (insn, fields, buf); + /* It is up to the caller to actually output the insn and any + queued relocs. */ + return insn; + } + + /* Try the next entry. */ + } + + /* FIXME: We can return a better error message than this. + Need to track why it failed and pick the right one. */ + { + static char errbuf[100]; + sprintf (errbuf, "bad instruction `%.50s%s'", + start, strlen (start) > 50 ? "..." : ""); + *errmsg = errbuf; + return NULL; + } +} + +#if 0 /* This calls back to GAS which we can't do without care. */ + +/* Record each member of OPVALS in the assembler's symbol table. + This lets GAS parse registers for us. + ??? Interesting idea but not currently used. */ + +/* Record each member of OPVALS in the assembler's symbol table. + FIXME: Not currently used. */ + +void +@arch@_cgen_asm_hash_keywords (opvals) + CGEN_KEYWORD *opvals; +{ + CGEN_KEYWORD_SEARCH search = cgen_keyword_search_init (opvals, NULL); + const CGEN_KEYWORD_ENTRY *ke; + + while ((ke = cgen_keyword_search_next (&search)) != NULL) + { +#if 0 /* Unnecessary, should be done in the search routine. */ + if (! @arch@_cgen_opval_supported (ke)) + continue; +#endif + cgen_asm_record_register (ke->name, ke->value); + } +} + +#endif /* 0 */ |