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view lwasm/insn_tfm.c @ 314:a3e277c58df9 ccdev
Checkpoint parser development for lwcc
Beginning of lemon based parser for C including all the infrastructure for
calling the lemon generated parser. This requires a translation layer from
the preprocessor token numbers to the lemon parser token numbers due to the
fact that lemon wants to control the token numbers. Eventually when the
lemon parser gets replaced with a hand crafted recursive descent parser,
this translation will no longer be required. However, in the interest of
getting things working sooner rather than later, using something like lemon
is beneficial.
author | William Astle <lost@l-w.ca> |
---|---|
date | Sun, 17 Nov 2013 11:59:36 -0700 |
parents | 09021ba6d755 |
children | 8764142b3192 |
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/* insn_tfm.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/>. */ #include <ctype.h> #include <string.h> #include "lwasm.h" #include "instab.h" PARSEFUNC(insn_parse_tfm) { static const char *reglist = "DXYUS AB 00EF"; int r0, r1; char *c; int tfm = 0; c = strchr(reglist, toupper(*(*p)++)); if (!c) { lwasm_register_error(as, l, "Unknown operation"); return; } r0 = c - reglist; if (**p == '+') { (*p)++; tfm = 1; } else if (**p == '-') { (*p)++; tfm = 2; } if (*(*p)++ != ',') { lwasm_register_error(as, l, "Unknown operation"); return; } c = strchr(reglist, toupper(*(*p)++)); if (!c) { lwasm_register_error(as, l, "Unknown operation"); return; } r1 = c - reglist; if (**p == '+') { (*p)++; tfm |= 4; } else if (**p == '-') { (*p)++; tfm |= 8; } if (**p && !isspace(**p)) { lwasm_register_error(as, l, "Bad operand"); return; } // valid values of tfm here are: // 1: r0+,r1 (2) // 4: r0,r1+ (3) // 5: r0+,r1+ (0) // 10: r0-,r1- (1) switch (tfm) { case 5: //r0+,r1+ l -> lint = instab[l -> insn].ops[0]; break; case 10: //r0-,r1- l -> lint = instab[l -> insn].ops[1]; break; case 1: // r0+,r1 l -> lint = instab[l -> insn].ops[2]; break; case 4: // r0,r1+ l -> lint = instab[l -> insn].ops[3]; break; default: lwasm_register_error(as, l, "Unknown operation"); return; } l -> pb = (r0 << 4) | r1; l -> len = OPLEN(l -> lint) + 1; } EMITFUNC(insn_emit_tfm) { lwasm_emitop(l, l -> lint); lwasm_emit(l, l -> pb); } PARSEFUNC(insn_parse_tfmrtor) { int r0, r1; static const char *regs = "D X Y U S A B 0 0 E F "; // register to register (r0,r1) // registers are in order: // D,X,Y,U,S,PC,W,V // A,B,CC,DP,0,0,E,F r0 = lwasm_lookupreg2(regs, p); if (r0 < 0 || *(*p)++ != ',') { lwasm_register_error(as, l, "Bad operand"); r0 = r1 = 0; } else { r1 = lwasm_lookupreg2(regs, p); if (r1 < 0) { lwasm_register_error(as, l, "Bad operand"); r0 = r1 = 0; } } l -> len = instab[l -> insn].ops[0] + 1; l -> pb = (r0 << 4) | r1; } EMITFUNC(insn_emit_tfmrtor) { lwasm_emitop(l, instab[l -> insn].ops[0]); lwasm_emit(l, l -> pb); }