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Diffstat (limited to 'opcodes/bpf-asm.c')
| -rw-r--r-- | opcodes/bpf-asm.c | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/opcodes/bpf-asm.c b/opcodes/bpf-asm.c new file mode 100644 index 0000000..4332edc --- /dev/null +++ b/opcodes/bpf-asm.c @@ -0,0 +1,590 @@ +/* DO NOT EDIT! -*- buffer-read-only: t -*- vi:set ro: */ +/* Assembler interface for targets using CGEN. -*- C -*- + CGEN: Cpu tools GENerator + + THIS FILE IS MACHINE GENERATED WITH CGEN. + - the resultant file is machine generated, cgen-asm.in isn't + + Copyright (C) 1996-2019 Free Software Foundation, Inc. + + This file is part of libopcodes. + + This library 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 3, or (at your option) + any later version. + + It 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., + 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ + + +/* ??? Eventually more and more of this stuff can go to cpu-independent files. + Keep that in mind. */ + +#include "sysdep.h" +#include <stdio.h> +#include "ansidecl.h" +#include "bfd.h" +#include "symcat.h" +#include "bpf-desc.h" +#include "bpf-opc.h" +#include "opintl.h" +#include "xregex.h" +#include "libiberty.h" +#include "safe-ctype.h" + +#undef min +#define min(a,b) ((a) < (b) ? (a) : (b)) +#undef max +#define max(a,b) ((a) > (b) ? (a) : (b)) + +static const char * parse_insn_normal + (CGEN_CPU_DESC, const CGEN_INSN *, const char **, CGEN_FIELDS *); + +/* -- assembler routines inserted here. */ + +/* -- asm.c */ + +/* Parse a signed 64-bit immediate. */ + +static const char * +parse_imm64 (CGEN_CPU_DESC cd, + const char **strp, + int opindex, + int64_t *valuep) +{ + bfd_vma value; + enum cgen_parse_operand_result result; + const char *errmsg; + + errmsg = (* cd->parse_operand_fn) + (cd, CGEN_PARSE_OPERAND_INTEGER, strp, opindex, BFD_RELOC_NONE, + &result, &value); + if (!errmsg) + *valuep = value; + + return errmsg; +} + +/* Endianness size operands are integer immediates whose values can be + 16, 32 or 64. */ + +static const char * +parse_endsize (CGEN_CPU_DESC cd, + const char **strp, + int opindex, + unsigned long *valuep) +{ + const char *errmsg; + + errmsg = cgen_parse_unsigned_integer (cd, strp, opindex, valuep); + if (errmsg) + return errmsg; + + switch (*valuep) + { + case 16: + case 32: + case 64: + break; + default: + return _("expected 16, 32 or 64 in"); + } + + return NULL; +} + +/* Special check to ensure that the right instruction variant is used + for the given endianness induced by the ISA selected in the CPU. + See bpf.cpu for a discussion on how eBPF is really two instruction + sets. */ + +int +bpf_cgen_insn_supported (CGEN_CPU_DESC cd, const CGEN_INSN *insn) +{ + CGEN_BITSET isas = CGEN_INSN_BITSET_ATTR_VALUE (insn, CGEN_INSN_ISA); + + return cgen_bitset_intersect_p (&isas, cd->isas); +} + + +/* -- dis.c */ + +const char * bpf_cgen_parse_operand + (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *); + +/* Main entry point for operand parsing. + + This function is basically just a big switch statement. Earlier versions + used tables to look up the function to use, but + - if the table contains both assembler and disassembler functions then + the disassembler contains much of the assembler and vice-versa, + - there's a lot of inlining possibilities as things grow, + - using a switch statement avoids the function call overhead. + + This function could be moved into `parse_insn_normal', but keeping it + separate makes clear the interface between `parse_insn_normal' and each of + the handlers. */ + +const char * +bpf_cgen_parse_operand (CGEN_CPU_DESC cd, + int opindex, + const char ** strp, + CGEN_FIELDS * fields) +{ + const char * errmsg = NULL; + /* Used by scalar operands that still need to be parsed. */ + long junk ATTRIBUTE_UNUSED; + + switch (opindex) + { + case BPF_OPERAND_DISP16 : + errmsg = cgen_parse_signed_integer (cd, strp, BPF_OPERAND_DISP16, (long *) (& fields->f_offset16)); + break; + case BPF_OPERAND_DISP32 : + errmsg = cgen_parse_signed_integer (cd, strp, BPF_OPERAND_DISP32, (long *) (& fields->f_imm32)); + break; + case BPF_OPERAND_DSTBE : + errmsg = cgen_parse_keyword (cd, strp, & bpf_cgen_opval_h_gpr, & fields->f_dstbe); + break; + case BPF_OPERAND_DSTLE : + errmsg = cgen_parse_keyword (cd, strp, & bpf_cgen_opval_h_gpr, & fields->f_dstle); + break; + case BPF_OPERAND_ENDSIZE : + errmsg = parse_endsize (cd, strp, BPF_OPERAND_ENDSIZE, (unsigned long *) (& fields->f_imm32)); + break; + case BPF_OPERAND_IMM32 : + errmsg = cgen_parse_signed_integer (cd, strp, BPF_OPERAND_IMM32, (long *) (& fields->f_imm32)); + break; + case BPF_OPERAND_IMM64 : + errmsg = parse_imm64 (cd, strp, BPF_OPERAND_IMM64, (int64_t *) (& fields->f_imm64)); + break; + case BPF_OPERAND_OFFSET16 : + errmsg = cgen_parse_signed_integer (cd, strp, BPF_OPERAND_OFFSET16, (long *) (& fields->f_offset16)); + break; + case BPF_OPERAND_SRCBE : + errmsg = cgen_parse_keyword (cd, strp, & bpf_cgen_opval_h_gpr, & fields->f_srcbe); + break; + case BPF_OPERAND_SRCLE : + errmsg = cgen_parse_keyword (cd, strp, & bpf_cgen_opval_h_gpr, & fields->f_srcle); + break; + + default : + /* xgettext:c-format */ + opcodes_error_handler + (_("internal error: unrecognized field %d while parsing"), + opindex); + abort (); + } + + return errmsg; +} + +cgen_parse_fn * const bpf_cgen_parse_handlers[] = +{ + parse_insn_normal, +}; + +void +bpf_cgen_init_asm (CGEN_CPU_DESC cd) +{ + bpf_cgen_init_opcode_table (cd); + bpf_cgen_init_ibld_table (cd); + cd->parse_handlers = & bpf_cgen_parse_handlers[0]; + cd->parse_operand = bpf_cgen_parse_operand; +#ifdef CGEN_ASM_INIT_HOOK +CGEN_ASM_INIT_HOOK +#endif +} + + + +/* Regex construction routine. + + This translates an opcode syntax string into a regex string, + by replacing any non-character syntax element (such as an + opcode) with the pattern '.*' + + It then compiles the regex and stores it in the opcode, for + later use by bpf_cgen_assemble_insn + + Returns NULL for success, an error message for failure. */ + +char * +bpf_cgen_build_insn_regex (CGEN_INSN *insn) +{ + CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn); + const char *mnem = CGEN_INSN_MNEMONIC (insn); + char rxbuf[CGEN_MAX_RX_ELEMENTS]; + char *rx = rxbuf; + const CGEN_SYNTAX_CHAR_TYPE *syn; + int reg_err; + + syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc)); + + /* Mnemonics come first in the syntax string. */ + if (! CGEN_SYNTAX_MNEMONIC_P (* syn)) + return _("missing mnemonic in syntax string"); + ++syn; + + /* Generate a case sensitive regular expression that emulates case + insensitive matching in the "C" locale. We cannot generate a case + insensitive regular expression because in Turkish locales, 'i' and 'I' + are not equal modulo case conversion. */ + + /* Copy the literal mnemonic out of the insn. */ + for (; *mnem; mnem++) + { + char c = *mnem; + + if (ISALPHA (c)) + { + *rx++ = '['; + *rx++ = TOLOWER (c); + *rx++ = TOUPPER (c); + *rx++ = ']'; + } + else + *rx++ = c; + } + + /* Copy any remaining literals from the syntax string into the rx. */ + for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn) + { + if (CGEN_SYNTAX_CHAR_P (* syn)) + { + char c = CGEN_SYNTAX_CHAR (* syn); + + switch (c) + { + /* Escape any regex metacharacters in the syntax. */ + case '.': case '[': case '\\': + case '*': case '^': case '$': + +#ifdef CGEN_ESCAPE_EXTENDED_REGEX + case '?': case '{': case '}': + case '(': case ')': case '*': + case '|': case '+': case ']': +#endif + *rx++ = '\\'; + *rx++ = c; + break; + + default: + if (ISALPHA (c)) + { + *rx++ = '['; + *rx++ = TOLOWER (c); + *rx++ = TOUPPER (c); + *rx++ = ']'; + } + else + *rx++ = c; + break; + } + } + else + { + /* Replace non-syntax fields with globs. */ + *rx++ = '.'; + *rx++ = '*'; + } + } + + /* Trailing whitespace ok. */ + * rx++ = '['; + * rx++ = ' '; + * rx++ = '\t'; + * rx++ = ']'; + * rx++ = '*'; + + /* But anchor it after that. */ + * rx++ = '$'; + * rx = '\0'; + + CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t)); + reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB); + + if (reg_err == 0) + return NULL; + else + { + static char msg[80]; + + regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80); + regfree ((regex_t *) CGEN_INSN_RX (insn)); + free (CGEN_INSN_RX (insn)); + (CGEN_INSN_RX (insn)) = NULL; + return msg; + } +} + + +/* 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 (CGEN_CPU_DESC cd, + const CGEN_INSN *insn, + const char **strp, + CGEN_FIELDS *fields) +{ + /* ??? Runtime added insns not handled yet. */ + const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn); + const char *str = *strp; + const char *errmsg; + const char *p; + const CGEN_SYNTAX_CHAR_TYPE * syn; +#ifdef CGEN_MNEMONIC_OPERANDS + /* FIXME: wip */ + 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. + GAS's input scrubber will ensure mnemonics are lowercase, but we may + not be called from GAS. */ + p = CGEN_INSN_MNEMONIC (insn); + while (*p && TOLOWER (*p) == TOLOWER (*str)) + ++p, ++str; + + if (* p) + return _("unrecognized instruction"); + +#ifndef CGEN_MNEMONIC_OPERANDS + if (* str && ! ISSPACE (* str)) + return _("unrecognized instruction"); +#endif + + CGEN_INIT_PARSE (cd); + cgen_init_parse_operand (cd); +#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 (syntax); + + /* 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. */ + if (CGEN_SYNTAX_CHAR_P (* syn)) + { + /* FIXME: While we allow for non-GAS callers above, we assume the + first char after the mnemonic part is a space. */ + /* FIXME: We also take inappropriate advantage of the fact that + GAS's input scrubber will remove extraneous blanks. */ + if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn))) + { +#ifdef CGEN_MNEMONIC_OPERANDS + if (CGEN_SYNTAX_CHAR(* syn) == ' ') + past_opcode_p = 1; +#endif + ++ syn; + ++ str; + } + else if (*str) + { + /* Syntax char didn't match. Can't be this insn. */ + static char msg [80]; + + /* xgettext:c-format */ + sprintf (msg, _("syntax error (expected char `%c', found `%c')"), + CGEN_SYNTAX_CHAR(*syn), *str); + return msg; + } + else + { + /* Ran out of input. */ + static char msg [80]; + + /* xgettext:c-format */ + sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"), + CGEN_SYNTAX_CHAR(*syn)); + return msg; + } + continue; + } + +#ifdef CGEN_MNEMONIC_OPERANDS + (void) past_opcode_p; +#endif + /* We have an operand of some sort. */ + errmsg = cd->parse_operand (cd, 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"); +} + +/* 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 assembled instruction, less any fixups, is stored in BUF. + Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value + still needs to be converted to target byte order, otherwise BUF is an array + of bytes in target byte order. + 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). + + Note that when processing (non-alias) macro-insns, + this function recurses. + + ??? It's possible to make this cpu-independent. + One would have to deal with a few minor things. + At this point in time doing so would be more of a curiosity than useful + [for example this file isn't _that_ big], but keeping the possibility in + mind helps keep the design clean. */ + +const CGEN_INSN * +bpf_cgen_assemble_insn (CGEN_CPU_DESC cd, + const char *str, + CGEN_FIELDS *fields, + CGEN_INSN_BYTES_PTR buf, + char **errmsg) +{ + const char *start; + CGEN_INSN_LIST *ilist; + const char *parse_errmsg = NULL; + const char *insert_errmsg = NULL; + int recognized_mnemonic = 0; + + /* 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 (cd, 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; + recognized_mnemonic = 1; + +#ifdef CGEN_VALIDATE_INSN_SUPPORTED + /* Not usually needed as unsupported opcodes + shouldn't be in the hash lists. */ + /* Is this insn supported by the selected cpu? */ + if (! bpf_cgen_insn_supported (cd, insn)) + continue; +#endif + /* If the RELAXED 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_VALUE (insn, CGEN_INSN_RELAXED) != 0) + continue; + + str = start; + + /* Skip this insn if str doesn't look right lexically. */ + if (CGEN_INSN_RX (insn) != NULL && + regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH) + continue; + + /* Allow parse/insert handlers to obtain length of insn. */ + CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn); + + parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields); + if (parse_errmsg != NULL) + continue; + + /* ??? 0 is passed for `pc'. */ + insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf, + (bfd_vma) 0); + if (insert_errmsg != NULL) + continue; + + /* It is up to the caller to actually output the insn and any + queued relocs. */ + return insn; + } + + { + static char errbuf[150]; + const char *tmp_errmsg; +#ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS +#define be_verbose 1 +#else +#define be_verbose 0 +#endif + + if (be_verbose) + { + /* If requesting verbose error messages, use insert_errmsg. + Failing that, use parse_errmsg. */ + tmp_errmsg = (insert_errmsg ? insert_errmsg : + parse_errmsg ? parse_errmsg : + recognized_mnemonic ? + _("unrecognized form of instruction") : + _("unrecognized instruction")); + + if (strlen (start) > 50) + /* xgettext:c-format */ + sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start); + else + /* xgettext:c-format */ + sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start); + } + else + { + if (strlen (start) > 50) + /* xgettext:c-format */ + sprintf (errbuf, _("bad instruction `%.50s...'"), start); + else + /* xgettext:c-format */ + sprintf (errbuf, _("bad instruction `%.50s'"), start); + } + + *errmsg = errbuf; + return NULL; + } +} |