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view lwasm/insn_gen.c @ 366:433dbc18fb41
Make byte overflow detection for 8 bit immediate not fail with COM operator
This is a horrible hack. Add a quick and dirty context to expression parsing
so that it knows whether an 8 bit or 16 bit complement is required. The 8
bit complement will just discard anything above bit 7. When returning an
operator back with lwasm_whichop(), the result will still be "COM" which
should allow other things to keep working as they already do.
This does prevent byte overflows when the complement operator is used,
however, and since those were introduced, there were problems building
Nitros9 among other things. This fix allows Nitros9 to build again.
author | William Astle <lost@l-w.ca> |
---|---|
date | Tue, 02 Jun 2015 20:58:14 -0600 |
parents | 3afb809c7add |
children | 8764142b3192 |
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/* insn_gen.c, Copyright © 2009 William Astle This file is part of LWASM. LWASM 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 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, see <http://www.gnu.org/licenses/>. Contains code for parsing general addressing modes (IMM+DIR+EXT+IND) */ #include <ctype.h> #include <stdlib.h> #include <lw_expr.h> #include "lwasm.h" #include "instab.h" extern void insn_indexed_parse_aux(asmstate_t *as, line_t *l, char **p); extern void insn_indexed_resolve_aux(asmstate_t *as, line_t *l, int force, int elen); extern void insn_indexed_emit_aux(asmstate_t *as, line_t *l); extern void insn_parse_indexed_aux(asmstate_t *as, line_t *l, char **p); extern void insn_resolve_indexed_aux(asmstate_t *as, line_t *l, int force, int elen); // "extra" is required due to the way OIM, EIM, TIM, and AIM work void insn_parse_gen_aux(asmstate_t *as, line_t *l, char **p, int elen) { const char *optr2; int v1, tv; lw_expr_t s; if (!**p) { lwasm_register_error(as, l, "Bad operand"); return; } optr2 = *p; while (*optr2 && !isspace(*optr2) && *optr2 != ',') optr2++ /* do nothing */ ; if (*optr2 == ',' || **p == '[') { l -> lint = -1; l -> lint2 = 1; insn_parse_indexed_aux(as, l, p); l -> minlen = OPLEN(instab[l -> insn].ops[1]) + 1 + elen; l -> maxlen = OPLEN(instab[l -> insn].ops[1]) + 3 + elen; goto out; } if (**p == '<') { (*p)++; l -> lint2 = 0; } // for compatibility with asxxxx // * followed by a digit, alpha, or _, or ., or ?, or another * is "f8" else if (**p == '*') { tv = *(*p + 1); if (isdigit(tv) || isalpha(tv) || tv == '_' || tv == '.' || tv == '?' || tv == '@' || tv == '*' || tv == '+' || tv == '-') { l -> lint2 = 0; (*p)++; } } else if (**p == '>') { (*p)++; l -> lint2 = 2; } else { l -> lint2 = -1; } l -> minlen = OPLEN(instab[l -> insn].ops[0]) + 1 + elen; l -> maxlen = OPLEN(instab[l -> insn].ops[2]) + 2 + elen; s = lwasm_parse_expr(as, p); if (!s) { lwasm_register_error(as, l, "Bad operand"); return; } lwasm_save_expr(l, 0, s); if (as -> output_format == OUTPUT_OBJ && l -> lint2 == -1) { l -> lint2 = 2; goto out; } if (l -> lint2 != -1) goto out; // if we have a constant now, figure out dp vs nondp if (lw_expr_istype(s, lw_expr_type_int)) { v1 = lw_expr_intval(s); if (((v1 >> 8) & 0xff) == (l -> dpval & 0xff)) { l -> lint2 = 0; goto out; } l -> lint2 = 2; } else { int min; int max; if (lwasm_calculate_range(as, s, &min, &max) == 0) { // fprintf(stderr, "range (P) %d...%d for %s\n", min, max, lw_expr_print(s)); if (min > max) { // we don't know what to do in this case so don't do anything goto out; } min = (min >> 8) & 0xff; max = (max >> 8) & 0xff; if ((l -> dpval & 0xff) < min || (l -> dpval & 0xff) > max) { l -> lint2 = 2; goto out; } if (min == max && (l -> dpval & 0xff) == min) { l -> lint2 = 0; goto out; } // if here, we don't know if the value is in the DP or not { l -> lint2 = -1; goto out; } } } out: if (l -> lint2 != -1) { if (l -> lint2 == 0) { l -> len = OPLEN(instab[l -> insn].ops[0]) + 1 + elen; } else if (l -> lint2 == 2) { l -> len = OPLEN(instab[l -> insn].ops[2]) + 2 + elen; } else if (l -> lint2 == 1 && l -> lint != -1) { l -> len = OPLEN(instab[l -> insn].ops[1]) + l -> lint + 1 + elen; } } } void insn_resolve_gen_aux(asmstate_t *as, line_t *l, int force, int elen) { lw_expr_t e; if (l -> lint2 == 1) { // indexed insn_resolve_indexed_aux(as, l, force, elen); goto out; } if (l -> lint2 != -1) return; e = lwasm_fetch_expr(l, 0); lwasm_reduce_expr(as, e); if (lw_expr_istype(e, lw_expr_type_int)) { int v; v = lw_expr_intval(e); if (((v >> 8) & 0xff) == (l -> dpval & 0xff)) { l -> lint2 = 0; goto out; } l -> lint2 = 2; goto out; } else { int min; int max; if (lwasm_calculate_range(as, e, &min, &max) == 0) { // fprintf(stderr, "range (R) %d...%d for %s\n", min, max, lw_expr_print(e)); if (min > max) { // we don't know what to do in this case so don't do anything goto out; } min = (min >> 8) & 0xff; max = (max >> 8) & 0xff; if ((l -> dpval & 0xff) < min || (l -> dpval & 0xff) > max) { l -> lint2 = 2; goto out; } if (min == max && (l -> dpval & 0xff) == min) { l -> lint2 = 0; goto out; } // if here, we don't know if the value is in the DP or not { l -> lint2 = -1; goto out; } } } if (force) { l -> lint2 = 2; } out: if (l -> lint2 != -1) { if (l -> lint2 == 0) { l -> len = OPLEN(instab[l -> insn].ops[0]) + 1 + elen; } else if (l -> lint2 == 2) { l -> len = OPLEN(instab[l -> insn].ops[2]) + 2 + elen; } else if (l -> lint2 == 1 && l -> lint != -1) { l -> len = OPLEN(instab[l -> insn].ops[1]) + l -> lint + 1 + elen; } } } void insn_emit_gen_aux(asmstate_t *as, line_t *l, int extra) { lw_expr_t e; e = lwasm_fetch_expr(l, 0); lwasm_emitop(l, instab[l -> insn].ops[l -> lint2]); if (extra != -1) lwasm_emit(l, extra); if (l -> lint2 == 1) { lwasm_emit(l, l -> pb); if (l -> lint > 0) { int i; i = lw_expr_intval(e); if (l -> lint == 1) { if (i < -128 || i > 127) lwasm_register_error(as, l, "Byte overflow"); } lwasm_emitexpr(l, e, l -> lint); } return; } if (l -> lint2 == 2) lwasm_emitexpr(l, e, 2); else lwasm_emitexpr(l, e, 1); } // the various insn_gen? functions have an immediate mode of ? bits PARSEFUNC(insn_parse_gen0) { if (**p == '#') { lwasm_register_error(as, l, "Immediate mode not allowed"); return; } // handle non-immediate insn_parse_gen_aux(as, l, p, 0); } RESOLVEFUNC(insn_resolve_gen0) { if (l -> len != -1) return; // handle non-immediate insn_resolve_gen_aux(as, l, force, 0); } EMITFUNC(insn_emit_gen0) { insn_emit_gen_aux(as, l, -1); } PARSEFUNC(insn_parse_gen8) { if (**p == '#') { lw_expr_t e; (*p)++; as -> exprwidth = 8; e = lwasm_parse_expr(as, p); as -> exprwidth = 16; if (!e) { lwasm_register_error(as, l, "Bad operand"); return; } l -> len = OPLEN(instab[l -> insn].ops[3]) + 1; l -> lint2 = 3; lwasm_save_expr(l, 0, e); return; } // handle non-immediate insn_parse_gen_aux(as, l, p, 0); if (l -> lint2 != -1) { if (l -> lint2 == 0) { l -> len = OPLEN(instab[l -> insn].ops[0]) + 1; } else if (l -> lint2 == 2) { l -> len = OPLEN(instab[l -> insn].ops[2]) + 2; } else if (l -> lint2 == 1 && l -> lint != -1) { l -> len = OPLEN(instab[l -> insn].ops[1]) + l -> lint + 1; } } } RESOLVEFUNC(insn_resolve_gen8) { if (l -> len != -1) return; // handle non-immediate insn_resolve_gen_aux(as, l, force, 0); } EMITFUNC(insn_emit_gen8) { if (l -> lint2 == 3) { lw_expr_t e; e = lwasm_fetch_expr(l, 0); if (lw_expr_istype(e, lw_expr_type_int)) { int i; i = lw_expr_intval(e); if (i < -128 || i > 255) { lwasm_register_error(as, l, "Byte overflow"); } } lwasm_emitop(l, instab[l -> insn].ops[3]); lwasm_emitexpr(l, e, 1); return; } insn_emit_gen_aux(as, l, -1); } PARSEFUNC(insn_parse_gen16) { if (**p == '#') { lw_expr_t e; (*p)++; e = lwasm_parse_expr(as, p); if (!e) { lwasm_register_error(as, l, "Bad operand"); return; } l -> len = OPLEN(instab[l -> insn].ops[3]) + 2; l -> lint2 = 3; lwasm_save_expr(l, 0, e); return; } // handle non-immediate insn_parse_gen_aux(as, l, p, 0); if (l -> lint2 != -1) { if (l -> lint2 == 0) { l -> len = OPLEN(instab[l -> insn].ops[0]) + 1; } else if (l -> lint2 == 2) { l -> len = OPLEN(instab[l -> insn].ops[2]) + 2; } else if (l -> lint2 == 1 && l -> lint != -1) { l -> len = OPLEN(instab[l -> insn].ops[1]) + l -> lint + 1; } } } RESOLVEFUNC(insn_resolve_gen16) { if (l -> len != -1) return; // handle non-immediate insn_resolve_gen_aux(as, l, force, 0); } EMITFUNC(insn_emit_gen16) { if (l -> lint2 == 3) { lw_expr_t e; e = lwasm_fetch_expr(l, 0); lwasm_emitop(l, instab[l -> insn].ops[3]); lwasm_emitexpr(l, e, 2); return; } insn_emit_gen_aux(as, l, -1); } PARSEFUNC(insn_parse_gen32) { if (**p == '#') { lw_expr_t e; (*p)++; e = lwasm_parse_expr(as, p); if (!e) { lwasm_register_error(as, l, "Bad operand"); return; } l -> len = OPLEN(instab[l -> insn].ops[3]) + 4; l -> lint2 = 3; lwasm_save_expr(l, 0, e); return; } // handle non-immediate insn_parse_gen_aux(as, l, p, 0); if (l -> lint2 != -1) { if (l -> lint2 == 0) { l -> len = OPLEN(instab[l -> insn].ops[0]) + 1; } else if (l -> lint2 == 2) { l -> len = OPLEN(instab[l -> insn].ops[2]) + 2; } else if (l -> lint2 == 1 && l -> lint != -1) { l -> len = OPLEN(instab[l -> insn].ops[1]) + l -> lint + 1; } } } RESOLVEFUNC(insn_resolve_gen32) { if (l -> len != -1) return; // handle non-immediate insn_resolve_gen_aux(as, l, force, 0); } EMITFUNC(insn_emit_gen32) { if (l -> lint2 == 3) { lw_expr_t e; e = lwasm_fetch_expr(l, 0); lwasm_emitop(l, instab[l -> insn].ops[3]); lwasm_emitexpr(l, e, 4); return; } insn_emit_gen_aux(as, l, -1); } PARSEFUNC(insn_parse_imm8) { lw_expr_t e; if (**p == '#') { (*p)++; as -> exprwidth = 8; e = lwasm_parse_expr(as, p); as -> exprwidth = 16; if (!e) { lwasm_register_error(as, l, "Bad operand"); return; } l -> len = OPLEN(instab[l -> insn].ops[0]) + 1; lwasm_save_expr(l, 0, e); } else { lwasm_register_error(as, l, "Bad operand"); } } EMITFUNC(insn_emit_imm8) { lw_expr_t e; lwasm_emitop(l, instab[l -> insn].ops[0]); e = lwasm_fetch_expr(l, 0); if (lw_expr_istype(e, lw_expr_type_int)) { int i; i = lw_expr_intval(e); if (i < -128 || i > 255) { lwasm_register_error(as, l, "Byte overflow"); } } lwasm_emitexpr(l, e, 1); }