/* $OpenBSD: local.c,v 1.4 2008/04/11 20:45:52 stefan Exp $ */ /* * Copyright (c) 2007 Michael Shalayeff * Copyright (c) 2003 Anders Magnusson (ragge@ludd.luth.se). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "pass1.h" #include "pass2.h" /* this file contains code which is dependent on the target machine */ struct symtab *makememcpy(void); /* clocal() is called to do local transformations on * an expression tree preparitory to its being * written out in intermediate code. * * the major essential job is rewriting the * automatic variables and arguments in terms of * REG and OREG nodes * conversion ops which are not necessary are also clobbered here * in addition, any special features (such as rewriting * exclusive or) are easily handled here as well */ NODE * clocal(NODE *p) { register struct symtab *q, *sp; register NODE *r, *l, *s; register int o, m, rn; char *ch, name[16]; TWORD t; #ifdef PCC_DEBUG if (xdebug) { printf("clocal: %p\n", p); fwalk(p, eprint, 0); } #endif switch (o = p->n_op) { case NAME: if ((q = p->n_sp) == NULL) break; /* Nothing to care about */ switch (q->sclass) { case PARAM: /* first four integral args are in regs */ rn = (q->soffset >> 5) - 8; if (rn < 4) { r = block(REG, NIL, NIL, p->n_type, 0, 0); r->n_lval = 0; switch (p->n_type) { case FLOAT: r->n_rval = FR7L - rn; break; case DOUBLE: case LDOUBLE: r->n_rval = FR6 - rn; break; case LONGLONG: case ULONGLONG: r->n_rval = AD1 - rn / 2; break; default: r->n_rval = ARG0 - rn; } r->n_sue = p->n_sue; p->n_sue = NULL; nfree(p); p = r; break; } /* FALLTHROUGH */ case AUTO: /* fake up a structure reference */ r = block(REG, NIL, NIL, PTR+STRTY, 0, 0); r->n_lval = 0; r->n_rval = FPREG; p = stref(block(STREF, r, p, 0, 0, 0)); break; case REGISTER: p->n_op = REG; p->n_lval = 0; p->n_rval = q->soffset; break; case STATIC: case EXTERN: if (strncmp(p->n_sp->soname, "__builtin", 9) == 0) break; l = block(REG, NIL, NIL, INT, 0, 0); l->n_lval = 0; l->n_rval = R1; l = block(ASSIGN, l, p, INT, 0, 0); r = xbcon(0, p->n_sp, INT); p = block(UMUL, block(PLUS, l, r, INT, 0, 0), NIL, p->n_type, p->n_df, p->n_sue); break; } break; case ADDROF: if (!ISFTN(p->n_left->n_type)) break; l = block(REG, NIL, NIL, INT, 0, 0); l->n_lval = 0; l->n_rval = R1; l = block(ASSIGN, l, p->n_left, INT, 0, 0); r = xbcon(0, p->n_left->n_sp, INT); l = block(PLUS, l, r, p->n_type, p->n_df, p->n_sue); nfree(p); p = l; break; case CBRANCH: l = p->n_left; /* * Remove unneccessary conversion ops. */ if (clogop(l->n_op) && l->n_left->n_op == SCONV) { if (coptype(l->n_op) != BITYPE) break; if (l->n_right->n_op == ICON) { r = l->n_left->n_left; if (r->n_type >= FLOAT && r->n_type <= LDOUBLE) break; /* Type must be correct */ t = r->n_type; nfree(l->n_left); l->n_left = r; l->n_type = t; l->n_right->n_type = t; } } break; case PCONV: /* Remove redundant PCONV's. Be careful */ l = p->n_left; if (l->n_op == ICON) { l->n_lval = (unsigned)l->n_lval; goto delp; } if (l->n_type < INT || l->n_type == LONGLONG || l->n_type == ULONGLONG) { /* float etc? */ p->n_left = block(SCONV, l, NIL, UNSIGNED, 0, MKSUE(UNSIGNED)); break; } /* if left is SCONV, cannot remove */ if (l->n_op == SCONV) break; /* avoid ADDROF TEMP */ if (l->n_op == ADDROF && l->n_left->n_op == TEMP) break; /* if conversion to another pointer type, just remove */ if (p->n_type > BTMASK && l->n_type > BTMASK) goto delp; break; delp: l->n_type = p->n_type; l->n_qual = p->n_qual; l->n_df = p->n_df; l->n_sue = p->n_sue; nfree(p); p = l; break; case SCONV: l = p->n_left; if (p->n_type == l->n_type) { nfree(p); p = l; break; } if ((p->n_type & TMASK) == 0 && (l->n_type & TMASK) == 0 && btdims[p->n_type].suesize == btdims[l->n_type].suesize) { if (p->n_type != FLOAT && p->n_type != DOUBLE && l->n_type != FLOAT && l->n_type != DOUBLE && l->n_type != LDOUBLE && p->n_type != LDOUBLE) { if (l->n_op == UMUL || l->n_op == TEMP || l->n_op == NAME) { l->n_type = p->n_type; nfree(p); p = l; break; } } } if (DEUNSIGN(p->n_type) == INT && DEUNSIGN(l->n_type) == INT && coptype(l->n_op) == BITYPE) { l->n_type = p->n_type; nfree(p); p = l; break; } o = l->n_op; m = p->n_type; if (o == ICON) { CONSZ val = l->n_lval; if (!ISPTR(m)) /* Pointers don't need to be conv'd */ switch (m) { case BOOL: l->n_lval = l->n_lval != 0; break; case CHAR: l->n_lval = (char)val; break; case UCHAR: l->n_lval = val & 0377; break; case SHORT: l->n_lval = (short)val; break; case USHORT: l->n_lval = val & 0177777; break; case ULONG: case UNSIGNED: l->n_lval = val & 0xffffffff; break; case LONG: case INT: l->n_lval = (int)val; break; case LONGLONG: l->n_lval = (long long)val; break; case ULONGLONG: l->n_lval = val; break; case VOID: break; case LDOUBLE: case DOUBLE: case FLOAT: l->n_op = FCON; l->n_dcon = val; break; default: cerror("unknown type %d", m); } l->n_type = m; l->n_sue = MKSUE(m); nfree(p); return l; } else if (l->n_op == FCON) { l->n_lval = l->n_dcon; l->n_sp = NULL; l->n_op = ICON; l->n_type = m; l->n_sue = MKSUE(m); nfree(p); return clocal(l); } if (DEUNSIGN(p->n_type) == SHORT && DEUNSIGN(l->n_type) == SHORT) { nfree(p); p = l; } if ((p->n_type == CHAR || p->n_type == UCHAR || p->n_type == SHORT || p->n_type == USHORT) && (l->n_type == FLOAT || l->n_type == DOUBLE || l->n_type == LDOUBLE)) { p = block(SCONV, p, NIL, p->n_type, p->n_df, p->n_sue); p->n_left->n_type = INT; break; } break; case MOD: case DIV: if (o == DIV && p->n_type != CHAR && p->n_type != SHORT) break; if (o == MOD && p->n_type != CHAR && p->n_type != SHORT) break; /* make it an int division by inserting conversions */ p->n_left = block(SCONV, p->n_left, NIL, INT, 0, MKSUE(INT)); p->n_right = block(SCONV, p->n_right, NIL, INT, 0, MKSUE(INT)); p = block(SCONV, p, NIL, p->n_type, 0, MKSUE(p->n_type)); p->n_left->n_type = INT; break; case PMCONV: case PVCONV: if( p->n_right->n_op != ICON ) cerror( "bad conversion", 0); nfree(p); return(buildtree(o==PMCONV?MUL:DIV, p->n_left, p->n_right)); case LS: case RS: /* shift count must be in an int */ if (p->n_right->n_op == ICON || p->n_right->n_lval <= 32) break; /* do not do anything */ if (p->n_right->n_type != INT || p->n_right->n_lval > 32) p->n_right = block(SCONV, p->n_right, NIL, INT, 0, MKSUE(INT)); break; #if 0 case FLD: /* already rewritten (in ASSIGN) */ if (p->n_left->n_op == TEMP) break; r = tempnode(0, p->n_type, p->n_df, p->n_sue); l = block(ASSIGN, r, p->n_left, p->n_type, p->n_df, p->n_sue); p->n_left = tcopy(r); p = block(COMOP, l, p, p->n_type, p->n_df, p->n_sue); break; #endif case FORCE: /* put return value in return reg */ p->n_op = ASSIGN; p->n_right = p->n_left; p->n_left = block(REG, NIL, NIL, p->n_type, p->n_df, p->n_sue); p->n_left->n_rval = p->n_left->n_type == BOOL ? RETREG(CHAR) : RETREG(p->n_type); if (p->n_right->n_op != FLD) break; break; case ASSIGN: r = p->n_right; l = p->n_left; /* rewrite ICON#0 into %r0 */ if (r->n_op == ICON && r->n_lval == 0 && (l->n_op == REG || l->n_op == OREG)) { r->n_op = REG; r->n_rval = R0; } /* rewrite FCON#0 into %fr0 */ if (r->n_op == FCON && r->n_lval == 0 && l->n_op == REG) { r->n_op = REG; r->n_rval = r->n_type == FLOAT? FR0L : FR0; } if (p->n_left->n_op != FLD) break; r = tempnode(0, l->n_type, l->n_df, l->n_sue); p = block(COMOP, block(ASSIGN, r, l->n_left, l->n_type, l->n_df, l->n_sue), p, p->n_type, p->n_df, p->n_sue); s = tcopy(l->n_left); p = block(COMOP, p, block(ASSIGN, s, tcopy(r), l->n_type, l->n_df, l->n_sue), p->n_type, p->n_df, p->n_sue); l->n_left = tcopy(r); break; case STASG: /* memcpy(left, right, size) */ sp = makememcpy(); l = p->n_left; /* guess struct return */ if (l->n_op == NAME && ISFTN(l->n_sp->stype)) { l = block(REG, NIL, NIL, VOID|PTR, 0, MKSUE(LONG)); l->n_lval = 0; l->n_rval = RET0; } else if (l->n_op == UMUL) l = tcopy(l->n_left); else if (l->n_op == NAME) l = block(ADDROF,tcopy(l),NIL,PTR|STRTY,0,MKSUE(LONG)); l = block(CALL, block(ADDROF, (s = block(NAME, NIL, NIL, FTN, 0, MKSUE(LONG))), NIL, PTR|FTN, 0, MKSUE(LONG)), block(CM, block(CM, l, tcopy(p->n_right), STRTY|PTR, 0, MKSUE(LONG)), (r = block(ICON, NIL, NIL, INT, 0, MKSUE(LONG))), 0, 0, 0), INT, 0, MKSUE(LONG)); r->n_lval = p->n_sue->suesize/SZCHAR; s->n_sp = sp; s->n_df = s->n_sp->sdf; defid(s, EXTERN); tfree(p); p = l; p->n_left = clocal(p->n_left); p->n_right = clocal(p->n_right); calldec(p->n_left, p->n_right); funcode(p); break; case STARG: /* arg = memcpy(argN-size, src, size) */ sp = makememcpy(); l = block(CALL, block(ADDROF, (s = block(NAME, NIL, NIL, FTN, 0, MKSUE(LONG))),NIL,0,0,0), block(CM, block(CM, tcopy(p), tcopy(p->n_left), 0, 0, 0), (r = block(ICON, NIL, NIL, INT, 0, MKSUE(LONG))), 0, 0, 0), INT, 0, MKSUE(LONG)); r->n_lval = p->n_sue->suesize/SZCHAR; s->n_sp = sp; s->n_df = s->n_sp->sdf; defid(s, EXTERN); tfree(p); p = l; p->n_left = clocal(p->n_left); calldec(p->n_left, p->n_right); funcode(p); break; case STCALL: case CALL: for (r = p->n_right; r->n_op == CM; r = r->n_left) { if (r->n_right->n_op == ASSIGN && r->n_right->n_right->n_op == CALL) { s = r->n_right->n_right; l = tempnode(0, s->n_type, s->n_df, s->n_sue); ecode(buildtree(ASSIGN, l, s)); r->n_right->n_right = tcopy(l); } if (r->n_left->n_op == ASSIGN && r->n_left->n_right->n_op == CALL) { s = r->n_left->n_right; l = tempnode(0, s->n_type, s->n_df, s->n_sue); ecode(buildtree(ASSIGN, l, s)); r->n_left->n_right = tcopy(l); } } break; } /* second pass - rewrite long ops */ switch (o) { case DIV: case MOD: case MUL: case RS: case LS: if (!(p->n_type == LONGLONG || p->n_type == ULONGLONG) || !((o == DIV || o == MOD || o == MUL) && p->n_type < FLOAT)) break; if (o == DIV && p->n_type == ULONGLONG) ch = "udiv"; else if (o == DIV) ch = "div"; else if (o == MUL) ch = "mul"; else if (o == MOD && p->n_type == ULONGLONG) ch = "umod"; else if (o == MOD) ch = "mod"; else if (o == RS && p->n_type == ULONGLONG) ch = "lshr"; else if (o == RS) ch = "ashr"; else if (o == LS) ch = "ashl"; else break; snprintf(name, sizeof(name), "__%sdi3", ch); p->n_right = block(CM, p->n_left, p->n_right, 0, 0, 0); p->n_left = block(ADDROF, block(NAME, NIL, NIL, FTN, 0, MKSUE(INT)), NIL, PTR|FTN, 0, MKSUE(INT)); p->n_left->n_left->n_sp = lookup(addname(name), 0); defid(p->n_left->n_left, EXTERN); p->n_left = clocal(p->n_left); calldec(p->n_left, p->n_right); p->n_op = CALL; funcode(p); break; } #ifdef PCC_DEBUG if (xdebug) { printf("clocal end: %p\n", p); fwalk(p, eprint, 0); } #endif return(p); } struct symtab * makememcpy() { NODE *memcpy, *args, *t, *u; struct symtab *sp; /* TODO check that it's a func proto */ if ((sp = lookup(addname("memcpy"), SNORMAL))) return sp; memcpy = block(NAME, NIL, NIL, 0, 0, MKSUE(LONG)); memcpy->n_sp = sp = lookup(addname("memcpy"), SNORMAL); defid(memcpy, EXTERN); args = block(CM, block(CM, block(NAME, NIL, NIL, VOID|PTR, 0, MKSUE(LONG)), block(NAME, NIL, NIL, VOID|PTR, 0, MKSUE(LONG)), 0, 0, 0), block(NAME, NIL, NIL, LONG, 0, MKSUE(LONG)), 0, 0, 0); tymerge(t = block(TYPE, NIL, NIL, VOID|PTR, 0, 0), (u = block(UMUL, block(CALL, memcpy, args, LONG, 0, 0), NIL, LONG, 0, 0))); tfree(t); tfree(u); return sp; } void myp2tree(NODE *p) { int o = p->n_op; if (o != FCON) return; /* Write float constants to memory */ /* Should be volontary per architecture */ #if 0 setloc1(RDATA); defalign(p->n_type == FLOAT ? ALFLOAT : p->n_type == DOUBLE ? ALDOUBLE : ALLDOUBLE ); deflab1(i = getlab()); #endif ninval(0, btdims[p->n_type].suesize, p); p->n_op = NAME; p->n_lval = 0; p->n_sp = tmpalloc(sizeof(struct symtab_hdr)); p->n_sp->sclass = ILABEL; p->n_sp->soffset = getlab(); p->n_sp->sflags = 0; } /*ARGSUSED*/ int andable(NODE *p) { return(1); /* all names can have & taken on them */ } /* * at the end of the arguments of a ftn, set the automatic offset */ void cendarg() { /* TODO can use to generate sp/rp tree ops? */ autooff = AUTOINIT; } /* * Return 1 if a variable of type "t" is OK to put in register. */ int cisreg(TWORD t) { return 1; } /* * return a node, for structure references, which is suitable for * being added to a pointer of type t, in order to be off bits offset * into a structure * t, d, and s are the type, dimension offset, and sizeoffset * For pdp10, return the type-specific index number which calculation * is based on its size. For example, short a[3] would return 3. * Be careful about only handling first-level pointers, the following * indirections must be fullword. */ NODE * offcon(OFFSZ off, TWORD t, union dimfun *d, struct suedef *sue) { register NODE *p; if (xdebug) printf("offcon: OFFSZ %lld type %x dim %p siz %d\n", off, t, d, sue->suesize); p = bcon(0); p->n_lval = off/SZCHAR; /* Default */ return(p); } /* * Allocate off bits on the stack. p is a tree that when evaluated * is the multiply count for off, t is a storeable node where to write * the allocated address. */ void spalloc(NODE *t, NODE *p, OFFSZ off) { NODE *sp; p = buildtree(MUL, p, bcon(off/SZCHAR)); /* XXX word alignment? */ /* sub the size from sp */ sp = block(REG, NIL, NIL, p->n_type, 0, MKSUE(INT)); sp->n_lval = 0; sp->n_rval = STKREG; ecomp(buildtree(PLUSEQ, sp, p)); /* save the address of sp */ sp = block(REG, NIL, NIL, PTR+INT, t->n_df, t->n_sue); sp->n_lval = 0; sp->n_rval = STKREG; t->n_type = sp->n_type; ecomp(buildtree(ASSIGN, t, sp)); /* Emit! */ } #if 0 /* * Print out an integer constant of size size. * can only be sizes <= SZINT. */ void indata(CONSZ val, int size) { switch (size) { case SZCHAR: printf("\t.byte %d\n", (int)val & 0xff); break; case SZSHORT: printf("\t.word %d\n", (int)val & 0xffff); break; case SZINT: printf("\t.long %d\n", (int)val & 0xffffffff); break; default: cerror("indata"); } } #endif /* * Print out a string of characters. * Assume that the assembler understands C-style escape * sequences. Location is already set. */ void instring(struct symtab *sp) { char *s, *str; defloc(sp); str = sp->sname; /* be kind to assemblers and avoid long strings */ printf("\t.ascii\t\""); for (s = str; *s != 0; ) { if (*s++ == '\\') { (void)esccon(&s); } if (s - str > 64) { fwrite(str, 1, s - str, stdout); printf("\"\n\t.ascii\t\""); str = s; } } fwrite(str, 1, s - str, stdout); printf("\\0\"\n"); } /* * Print out a wide string by calling ninval(). */ void inwstring(struct symtab *sp) { char *s = sp->sname; NODE *p; defloc(sp); p = bcon(0); do { if (*s++ == '\\') p->n_lval = esccon(&s); else p->n_lval = (unsigned char)s[-1]; ninval(0, (MKSUE(WCHAR_TYPE))->suesize, p); } while (s[-1] != 0); nfree(p); } static int inbits, inval; /* * set fsz bits in sequence to zero. */ void zbits(OFFSZ off, int fsz) { int m; if (idebug) printf("zbits off %lld, fsz %d inbits %d\n", off, fsz, inbits); if ((m = (inbits % SZCHAR))) { m = SZCHAR - m; if (fsz < m) { inbits += fsz; return; } else { fsz -= m; printf("\t.byte %d\n", inval); inval = inbits = 0; } } if (fsz >= SZCHAR) { printf("\t.zero %d\n", fsz/SZCHAR); fsz -= (fsz/SZCHAR) * SZCHAR; } if (fsz) { inval = 0; inbits = fsz; } } /* * Initialize a bitfield. */ void infld(CONSZ off, int fsz, CONSZ val) { if (idebug) printf("infld off %lld, fsz %d, val %lld inbits %d\n", off, fsz, val, inbits); val &= (1 << fsz)-1; while (fsz + inbits >= SZCHAR) { inval |= (val << inbits); printf("\t.byte %d\n", inval & 255); fsz -= (SZCHAR - inbits); val >>= (SZCHAR - inbits); inval = inbits = 0; } if (fsz) { inval |= (val << inbits); inbits += fsz; } } /* * print out a constant node, may be associated with a label. * Do not free the node after use. * off is bit offset from the beginning of the aggregate * fsz is the number of bits this is referring to * * XXX this relies on the host fp numbers representation */ void ninval(CONSZ off, int fsz, NODE *p) { union { float f; double d; long double l; int i[3]; } u; struct symtab *q; TWORD t; int i; t = p->n_type; if (t > BTMASK) t = INT; /* pointer */ if (p->n_op != ICON && p->n_op != FCON) cerror("ninval: init node not constant"); if (p->n_op == ICON && p->n_sp != NULL && DEUNSIGN(t) != INT) uerror("element not constant"); switch (t) { case LONGLONG: case ULONGLONG: i = (p->n_lval >> 32); p->n_lval &= 0xffffffff; p->n_type = INT; ninval(off, 32, p); p->n_lval = i; ninval(off+32, 32, p); break; case INT: case UNSIGNED: printf("\t.long 0x%x", (int)p->n_lval); if ((q = p->n_sp) != NULL) { if ((q->sclass == STATIC && q->slevel > 0) || q->sclass == ILABEL) { printf("+" LABFMT, q->soffset); } else printf("+%s", exname(q->soname)); } printf("\n"); break; case SHORT: case USHORT: printf("\t.short 0x%x\n", (int)p->n_lval & 0xffff); break; case BOOL: if (p->n_lval > 1) p->n_lval = p->n_lval != 0; /* FALLTHROUGH */ case CHAR: case UCHAR: /* TODO make the upper layer give an .asciz */ printf("\t.byte %d\n", (int)p->n_lval & 0xff); break; case LDOUBLE: case DOUBLE: u.d = (double)p->n_dcon; printf("\t.long\t0x%x,0x%x\n", u.i[0], u.i[1]); break; case FLOAT: u.f = (float)p->n_dcon; printf("\t.long\t0x%x\n", u.i[0]); break; default: cerror("ninval"); } } /* make a name look like an external name in the local machine */ char * exname(char *p) { if (p == NULL) return ""; return p; } /* * map types which are not defined on the local machine */ TWORD ctype(TWORD type) { switch (BTYPE(type)) { case LONG: MODTYPE(type,INT); break; case ULONG: MODTYPE(type,UNSIGNED); } return (type); } void calldec(NODE *f, NODE *a) { struct symtab *q; if (f->n_op == UMUL && f->n_left->n_op == PLUS && f->n_left->n_right->n_op == ICON) q = f->n_left->n_right->n_sp; else if (f->n_op == PLUS && f->n_right->n_op == ICON) q = f->n_right->n_sp; else { fwalk(f, eprint, 0); cerror("unknown function"); return; } printf("\t.import\t%s,code\n", exname(q->soname)); } void extdec(struct symtab *q) { printf("\t.import\t%s,data\n", exname(q->soname)); } /* make a common declaration for id, if reasonable */ void defzero(struct symtab *sp) { int off; off = tsize(sp->stype, sp->sdf, sp->ssue); off = (off + (SZCHAR - 1)) / SZCHAR; printf("\t.%scomm\t", sp->sclass == STATIC ? "l" : ""); if (sp->slevel == 0) printf("%s,0%o\n", exname(sp->soname), off); else printf(LABFMT ",0%o\n", sp->soffset, off); } char *nextsect; #define SSECTION 010000 /* * Give target the opportunity of handling pragmas. */ int mypragma(char **ary) { if (strcmp(ary[1], "section") || ary[2] == NULL) return 0; nextsect = newstring(ary[2], strlen(ary[2])); return 1; } /* * Called when a identifier has been declared, to give target last word. */ void fixdef(struct symtab *sp) { }