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// Inferno utils/5l/obj.c
// http://code.google.com/p/inferno-os/source/browse/utils/5l/obj.c
//
// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
// Portions Copyright © 1997-1999 Vita Nuova Limited
// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
// Portions Copyright © 2004,2006 Bruce Ellis
// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
// Portions Copyright © 2009 The Go Authors. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#define EXTERN
#include "l.h"
#include "../ld/lib.h"
#include <ar.h>
#ifndef DEFAULT
#define DEFAULT '9'
#endif
char *noname = "<none>";
char thechar = '5';
char *thestring = "arm";
/*
* -H1 -T0x10005000 -R4 is aif for risc os
* -H2 -T4128 -R4096 is plan9 format
* -H3 -T0xF0000020 -R4 is NetBSD format
* -H4 is IXP1200 (raw)
* -H5 -T0xC0008010 -R1024 is ipaq
*/
static int
isobjfile(char *f)
{
int n, v;
Biobuf *b;
char buf1[5], buf2[SARMAG];
b = Bopen(f, OREAD);
if(b == nil)
return 0;
n = Bread(b, buf1, 5);
if(n == 5 && (buf1[2] == 1 && buf1[3] == '<' || buf1[3] == 1 && buf1[4] == '<'))
v = 1; /* good enough for our purposes */
else{
Bseek(b, 0, 0);
n = Bread(b, buf2, SARMAG);
v = n == SARMAG && strncmp(buf2, ARMAG, SARMAG) == 0;
}
Bterm(b);
return v;
}
static char*
linkername[] =
{
"runtime·softfloat",
};
void
usage(void)
{
fprint(2, "usage: 5l [-options] objects\n");
errorexit();
}
void
main(int argc, char *argv[])
{
int c, i;
Binit(&bso, 1, OWRITE);
cout = -1;
listinit();
nerrors = 0;
curtext = P;
outfile = "5.out";
HEADTYPE = -1;
INITTEXT = -1;
INITDAT = -1;
INITRND = -1;
INITENTRY = 0;
ARGBEGIN {
default:
c = ARGC();
if(c >= 0 && c < sizeof(debug))
debug[c]++;
break;
case 'o':
outfile = EARGF(usage());
break;
case 'E':
INITENTRY = EARGF(usage());
break;
case 'L':
Lflag(EARGF(usage()));
break;
case 'T':
INITTEXT = atolwhex(EARGF(usage()));
break;
case 'D':
INITDAT = atolwhex(EARGF(usage()));
break;
case 'R':
INITRND = atolwhex(EARGF(usage()));
break;
case 'H':
HEADTYPE = atolwhex(EARGF(usage()));
/* do something about setting INITTEXT */
break;
case 'x': /* produce export table */
doexp = 1;
if(argv[1] != nil && argv[1][0] != '-' && !isobjfile(argv[1]))
readundefs(ARGF(), SEXPORT);
break;
case 'u': /* produce dynamically loadable module */
dlm = 1;
debug['l']++;
if(argv[1] != nil && argv[1][0] != '-' && !isobjfile(argv[1]))
readundefs(ARGF(), SIMPORT);
break;
} ARGEND
USED(argc);
if(*argv == 0)
usage();
libinit();
if(!debug['9'] && !debug['U'] && !debug['B'])
debug[DEFAULT] = 1;
if(HEADTYPE == -1) {
if(debug['U'])
HEADTYPE = 0;
if(debug['B'])
HEADTYPE = 1;
if(debug['9'])
HEADTYPE = 2;
HEADTYPE = 6;
}
switch(HEADTYPE) {
default:
diag("unknown -H option");
errorexit();
case 0: /* no header */
HEADR = 0L;
if(INITTEXT == -1)
INITTEXT = 0;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4;
break;
case 1: /* aif for risc os */
HEADR = 128L;
if(INITTEXT == -1)
INITTEXT = 0x10005000 + HEADR;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4;
break;
case 2: /* plan 9 */
HEADR = 32L;
if(INITTEXT == -1)
INITTEXT = 4128;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4096;
break;
case 3: /* boot for NetBSD */
HEADR = 32L;
if(INITTEXT == -1)
INITTEXT = 0xF0000020L;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4096;
break;
case 4: /* boot for IXP1200 */
HEADR = 0L;
if(INITTEXT == -1)
INITTEXT = 0x0;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4;
break;
case 5: /* boot for ipaq */
HEADR = 16L;
if(INITTEXT == -1)
INITTEXT = 0xC0008010;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 1024;
break;
case 6: /* arm elf */
HEADR = linuxheadr();
if(INITTEXT == -1)
INITTEXT = 0x8000+HEADR;
if(INITDAT == -1)
INITDAT = 0;
if(INITRND == -1)
INITRND = 4096;
break;
}
if(INITDAT != 0 && INITRND != 0)
print("warning: -D0x%lux is ignored because of -R0x%lux\n",
INITDAT, INITRND);
if(debug['v'])
Bprint(&bso, "HEADER = -H0x%d -T0x%lux -D0x%lux -R0x%lux\n",
HEADTYPE, INITTEXT, INITDAT, INITRND);
Bflush(&bso);
zprg.as = AGOK;
zprg.scond = 14;
zprg.reg = NREG;
zprg.from.name = D_NONE;
zprg.from.type = D_NONE;
zprg.from.reg = NREG;
zprg.to = zprg.from;
buildop();
thumbbuildop(); // could build on demand
histgen = 0;
textp = P;
datap = P;
edatap = P;
pc = 0;
dtype = 4;
nuxiinit();
version = 0;
cbp = buf.cbuf;
cbc = sizeof(buf.cbuf);
firstp = prg();
lastp = firstp;
while(*argv)
objfile(*argv++);
if(!debug['l'])
loadlib();
// mark some functions that are only referenced after linker code editing
// TODO(kaib): this doesn't work, the prog can't be found in runtime
for(i=0; i<nelem(linkername); i++)
mark(lookup(linkername[i], 0));
deadcode();
firstp = firstp->link;
if(firstp == P)
goto out;
if(doexp || dlm){
EXPTAB = "_exporttab";
zerosig(EXPTAB);
zerosig("etext");
zerosig("edata");
zerosig("end");
if(dlm){
initdiv();
import();
HEADTYPE = 2;
INITTEXT = INITDAT = 0;
INITRND = 8;
INITENTRY = EXPTAB;
}
else
divsig();
export();
}
patch();
if(debug['p'])
if(debug['1'])
doprof1();
else
doprof2();
if(debug['u'])
reachable();
dodata();
if(seenthumb && debug['f'])
fnptrs();
follow();
if(firstp == P)
goto out;
softfloat();
noops();
span();
asmb();
undef();
out:
if(debug['c']){
thumbcount();
print("ARM size = %d\n", armsize);
}
if(debug['v']) {
Bprint(&bso, "%5.2f cpu time\n", cputime());
Bprint(&bso, "%d sizeof adr\n", sizeof(Adr));
Bprint(&bso, "%d sizeof prog\n", sizeof(Prog));
}
Bflush(&bso);
errorexit();
}
void
zaddr(Biobuf *f, Adr *a, Sym *h[])
{
int i, c;
int32 l;
Sym *s;
Auto *u;
a->type = Bgetc(f);
a->reg = Bgetc(f);
c = Bgetc(f);
if(c < 0 || c > NSYM){
print("sym out of range: %d\n", c);
Bputc(f, ALAST+1);
return;
}
a->sym = h[c];
a->name = Bgetc(f);
if(a->reg < 0 || a->reg > NREG) {
print("register out of range %d\n", a->reg);
Bputc(f, ALAST+1);
return; /* force real diagnostic */
}
if(a->type == D_CONST || a->type == D_OCONST) {
if(a->name == D_EXTERN || a->name == D_STATIC) {
s = a->sym;
if(s != S && (s->type == STEXT || s->type == SLEAF || s->type == SCONST || s->type == SXREF)) {
if(0 && !s->fnptr && s->name[0] != '.')
print("%s used as function pointer\n", s->name);
s->fnptr = 1; // over the top cos of SXREF
}
}
}
switch(a->type) {
default:
print("unknown type %d\n", a->type);
Bputc(f, ALAST+1);
return; /* force real diagnostic */
case D_NONE:
case D_REG:
case D_FREG:
case D_PSR:
case D_FPCR:
break;
case D_REGREG:
a->offset = Bgetc(f);
c++;
break;
case D_CONST2:
a->offset2 = Bget4(f); // fall through
case D_BRANCH:
case D_OREG:
case D_CONST:
case D_OCONST:
case D_SHIFT:
a->offset = Bget4(f);
break;
case D_SCONST:
a->sval = mal(NSNAME);
Bread(f, a->sval, NSNAME);
c += NSNAME;
break;
case D_FCONST:
a->ieee = mal(sizeof(Ieee));
a->ieee->l = Bget4(f);
a->ieee->h = Bget4(f);
break;
}
s = a->sym;
if(s == S)
return;
i = a->name;
if(i != D_AUTO && i != D_PARAM)
return;
l = a->offset;
for(u=curauto; u; u=u->link)
if(u->asym == s)
if(u->type == i) {
if(u->aoffset > l)
u->aoffset = l;
return;
}
u = mal(sizeof(Auto));
u->link = curauto;
curauto = u;
u->asym = s;
u->aoffset = l;
u->type = i;
}
void
nopout(Prog *p)
{
p->as = ANOP;
p->from.type = D_NONE;
p->to.type = D_NONE;
}
static void puntfp(Prog *);
void
ldobj1(Biobuf *f, int64 len, char *pn)
{
int32 ipc;
Prog *p, *t;
Sym *h[NSYM], *s, *di;
int v, o, r, skip;
uint32 sig;
char *name;
int ntext;
int32 eof;
char src[1024];
ntext = 0;
eof = Boffset(f) + len;
di = S;
src[0] = 0;
newloop:
memset(h, 0, sizeof(h));
version++;
histfrogp = 0;
ipc = pc;
skip = 0;
loop:
if(f->state == Bracteof || Boffset(f) >= eof)
goto eof;
o = Bgetc(f);
if(o == Beof)
goto eof;
if(o <= AXXX || o >= ALAST) {
diag("%s:#%lld: opcode out of range: %#ux", pn, Boffset(f), o);
print(" probably not a .5 file\n");
errorexit();
}
if(o == ANAME || o == ASIGNAME) {
sig = 0;
if(o == ASIGNAME)
sig = Bget4(f);
v = Bgetc(f); /* type */
o = Bgetc(f); /* sym */
r = 0;
if(v == D_STATIC)
r = version;
name = Brdline(f, '\0');
if(name == nil) {
if(Blinelen(f) > 0) {
fprint(2, "%s: name too long\n", pn);
errorexit();
}
goto eof;
}
s = lookup(name, r);
if(sig != 0){
if(s->sig != 0 && s->sig != sig)
diag("incompatible type signatures %lux(%s) and %lux(%s) for %s", s->sig, s->file, sig, pn, s->name);
s->sig = sig;
s->file = pn;
}
if(debug['W'])
print(" ANAME %s\n", s->name);
h[o] = s;
if((v == D_EXTERN || v == D_STATIC) && s->type == 0)
s->type = SXREF;
if(v == D_FILE) {
if(s->type != SFILE) {
histgen++;
s->type = SFILE;
s->value = histgen;
}
if(histfrogp < MAXHIST) {
histfrog[histfrogp] = s;
histfrogp++;
} else
collapsefrog(s);
}
goto loop;
}
p = mal(sizeof(Prog));
p->as = o;
p->scond = Bgetc(f);
p->reg = Bgetc(f);
p->line = Bget4(f);
zaddr(f, &p->from, h);
zaddr(f, &p->to, h);
if(p->reg > NREG)
diag("register out of range %d", p->reg);
p->link = P;
p->cond = P;
if(debug['W'])
print("%P\n", p);
switch(o) {
case AHISTORY:
if(p->to.offset == -1) {
addlib(src, pn);
histfrogp = 0;
goto loop;
}
if(src[0] == '\0')
copyhistfrog(src, sizeof src);
addhist(p->line, D_FILE); /* 'z' */
if(p->to.offset)
addhist(p->to.offset, D_FILE1); /* 'Z' */
histfrogp = 0;
goto loop;
case AEND:
histtoauto();
if(curtext != P)
curtext->to.autom = curauto;
curauto = 0;
curtext = P;
if(Boffset(f) == eof)
return;
goto newloop;
case AGLOBL:
s = p->from.sym;
if(s == S) {
diag("GLOBL must have a name\n%P", p);
errorexit();
}
if(s->type == 0 || s->type == SXREF) {
s->type = SBSS;
s->value = 0;
}
if(s->type != SBSS) {
diag("redefinition: %s\n%P", s->name, p);
s->type = SBSS;
s->value = 0;
}
if(p->to.offset > s->value)
s->value = p->to.offset;
if(p->reg & DUPOK)
s->dupok = 1;
break;
case ADYNT:
s = p->from.sym;
if(p->to.sym == S) {
diag("DYNT without a sym\n%P", p);
break;
}
di = p->to.sym;
p->reg = 4;
if(di->type == SXREF) {
if(debug['z'])
Bprint(&bso, "%P set to %d\n", p, dtype);
di->type = SCONST;
di->value = dtype;
dtype += 4;
}
if(s == S)
break;
p->from.offset = di->value;
s->type = SDATA;
if(curtext == P) {
diag("DYNT not in text: %P", p);
break;
}
p->to.sym = curtext->from.sym;
p->to.type = D_CONST;
if(s != S) {
p->dlink = s->data;
s->data = p;
}
if(edatap == P)
datap = p;
else
edatap->link = p;
edatap = p;
break;
case AINIT:
s = p->from.sym;
if(s == S) {
diag("INIT without a sym\n%P", p);
break;
}
if(di == S) {
diag("INIT without previous DYNT\n%P", p);
break;
}
p->from.offset = di->value;
s->type = SDATA;
if(s != S) {
p->dlink = s->data;
s->data = p;
}
if(edatap == P)
datap = p;
else
edatap->link = p;
edatap = p;
break;
case ADATA:
// Assume that AGLOBL comes after ADATA.
// If we've seen an AGLOBL that said this sym was DUPOK,
// ignore any more ADATA we see, which must be
// redefinitions.
s = p->from.sym;
if(s != S && s->dupok) {
if(debug['v'])
Bprint(&bso, "skipping %s in %s: dupok\n", s->name, pn);
goto loop;
}
if(s != S) {
p->dlink = s->data;
s->data = p;
}
if(edatap == P)
datap = p;
else
edatap->link = p;
edatap = p;
break;
case AGOK:
diag("unknown opcode\n%P", p);
p->pc = pc;
pc++;
break;
case ATEXT:
s = p->from.sym;
if(ntext++ == 0 && s->type != 0 && s->type != SXREF) {
/* redefinition, so file has probably been seen before */
if(debug['v'])
Bprint(&bso, "skipping: %s: redefinition: %s", pn, s->name);
return;
}
setarch(p);
setthumb(p);
p->align = 4;
if(curtext != P) {
histtoauto();
curtext->to.autom = curauto;
curauto = 0;
}
skip = 0;
curtext = p;
autosize = (p->to.offset+3L) & ~3L;
p->to.offset = autosize;
autosize += 4;
s = p->from.sym;
if(s == S) {
diag("TEXT must have a name\n%P", p);
errorexit();
}
if(s->type != 0 && s->type != SXREF) {
if(p->reg & DUPOK) {
skip = 1;
goto casedef;
}
diag("redefinition: %s\n%P", s->name, p);
}
s->type = STEXT;
s->text = p;
s->value = pc;
s->thumb = thumb;
lastp->link = p;
lastp = p;
p->pc = pc;
pc++;
if(textp == P) {
textp = p;
etextp = p;
goto loop;
}
etextp->cond = p;
etextp = p;
break;
case ASUB:
if(p->from.type == D_CONST)
if(p->from.name == D_NONE)
if(p->from.offset < 0) {
p->from.offset = -p->from.offset;
p->as = AADD;
}
goto casedef;
case AADD:
if(p->from.type == D_CONST)
if(p->from.name == D_NONE)
if(p->from.offset < 0) {
p->from.offset = -p->from.offset;
p->as = ASUB;
}
goto casedef;
case AMOVWD:
case AMOVWF:
case AMOVDW:
case AMOVFW:
case AMOVFD:
case AMOVDF:
// case AMOVF:
// case AMOVD:
case ACMPF:
case ACMPD:
case AADDF:
case AADDD:
case ASUBF:
case ASUBD:
case AMULF:
case AMULD:
case ADIVF:
case ADIVD:
if(thumb)
puntfp(p);
goto casedef;
case AMOVF:
if(thumb)
puntfp(p);
if(skip)
goto casedef;
if(p->from.type == D_FCONST && chipfloat(p->from.ieee) < 0) {
/* size sb 9 max */
sprint(literal, "$%lux", ieeedtof(p->from.ieee));
s = lookup(literal, 0);
if(s->type == 0) {
s->type = SBSS;
s->value = 4;
t = prg();
t->as = ADATA;
t->line = p->line;
t->from.type = D_OREG;
t->from.sym = s;
t->from.name = D_EXTERN;
t->reg = 4;
t->to = p->from;
if(edatap == P)
datap = t;
else
edatap->link = t;
edatap = t;
t->link = P;
}
p->from.type = D_OREG;
p->from.sym = s;
p->from.name = D_EXTERN;
p->from.offset = 0;
}
goto casedef;
case AMOVD:
if(thumb)
puntfp(p);
if(skip)
goto casedef;
if(p->from.type == D_FCONST && chipfloat(p->from.ieee) < 0) {
/* size sb 18 max */
sprint(literal, "$%lux.%lux",
p->from.ieee->l, p->from.ieee->h);
s = lookup(literal, 0);
if(s->type == 0) {
s->type = SBSS;
s->value = 8;
t = prg();
t->as = ADATA;
t->line = p->line;
t->from.type = D_OREG;
t->from.sym = s;
t->from.name = D_EXTERN;
t->reg = 8;
t->to = p->from;
if(edatap == P)
datap = t;
else
edatap->link = t;
edatap = t;
t->link = P;
}
p->from.type = D_OREG;
p->from.sym = s;
p->from.name = D_EXTERN;
p->from.offset = 0;
}
goto casedef;
default:
casedef:
if(skip)
nopout(p);
if(p->to.type == D_BRANCH)
p->to.offset += ipc;
lastp->link = p;
lastp = p;
p->pc = pc;
pc++;
break;
}
goto loop;
eof:
diag("truncated object file: %s", pn);
}
Prog*
prg(void)
{
Prog *p;
p = mal(sizeof(Prog));
*p = zprg;
return p;
}
void
doprof1(void)
{
Sym *s;
int32 n;
Prog *p, *q;
if(debug['v'])
Bprint(&bso, "%5.2f profile 1\n", cputime());
Bflush(&bso);
s = lookup("__mcount", 0);
n = 1;
for(p = firstp->link; p != P; p = p->link) {
setarch(p);
if(p->as == ATEXT) {
q = prg();
q->line = p->line;
q->link = datap;
datap = q;
q->as = ADATA;
q->from.type = D_OREG;
q->from.name = D_EXTERN;
q->from.offset = n*4;
q->from.sym = s;
q->reg = 4;
q->to = p->from;
q->to.type = D_CONST;
q = prg();
q->line = p->line;
q->pc = p->pc;
q->link = p->link;
p->link = q;
p = q;
p->as = AMOVW;
p->from.type = D_OREG;
p->from.name = D_EXTERN;
p->from.sym = s;
p->from.offset = n*4 + 4;
p->to.type = D_REG;
p->to.reg = thumb ? REGTMPT : REGTMP;
q = prg();
q->line = p->line;
q->pc = p->pc;
q->link = p->link;
p->link = q;
p = q;
p->as = AADD;
p->from.type = D_CONST;
p->from.offset = 1;
p->to.type = D_REG;
p->to.reg = thumb ? REGTMPT : REGTMP;
q = prg();
q->line = p->line;
q->pc = p->pc;
q->link = p->link;
p->link = q;
p = q;
p->as = AMOVW;
p->from.type = D_REG;
p->from.reg = thumb ? REGTMPT : REGTMP;
p->to.type = D_OREG;
p->to.name = D_EXTERN;
p->to.sym = s;
p->to.offset = n*4 + 4;
n += 2;
continue;
}
}
q = prg();
q->line = 0;
q->link = datap;
datap = q;
q->as = ADATA;
q->from.type = D_OREG;
q->from.name = D_EXTERN;
q->from.sym = s;
q->reg = 4;
q->to.type = D_CONST;
q->to.offset = n;
s->type = SBSS;
s->value = n*4;
}
void
doprof2(void)
{
Sym *s2, *s4;
Prog *p, *q, *ps2, *ps4;
if(debug['v'])
Bprint(&bso, "%5.2f profile 2\n", cputime());
Bflush(&bso);
s2 = lookup("_profin", 0);
s4 = lookup("_profout", 0);
if(s2->type != STEXT || s4->type != STEXT) {
diag("_profin/_profout not defined");
return;
}
ps2 = P;
ps4 = P;
for(p = firstp; p != P; p = p->link) {
setarch(p);
if(p->as == ATEXT) {
if(p->from.sym == s2) {
ps2 = p;
p->reg = 1;
}
if(p->from.sym == s4) {
ps4 = p;
p->reg = 1;
}
}
}
for(p = firstp; p != P; p = p->link) {
setarch(p);
if(p->as == ATEXT) {
if(p->reg & NOPROF) {
for(;;) {
q = p->link;
if(q == P)
break;
if(q->as == ATEXT)
break;
p = q;
}
continue;
}
/*
* BL profin, R2
*/
q = prg();
q->line = p->line;
q->pc = p->pc;
q->link = p->link;
p->link = q;
p = q;
p->as = ABL;
p->to.type = D_BRANCH;
p->cond = ps2;
p->to.sym = s2;
continue;
}
if(p->as == ARET) {
/*
* RET
*/
q = prg();
q->as = ARET;
q->from = p->from;
q->to = p->to;
q->link = p->link;
p->link = q;
/*
* BL profout
*/
p->as = ABL;
p->from = zprg.from;
p->to = zprg.to;
p->to.type = D_BRANCH;
p->cond = ps4;
p->to.sym = s4;
p = q;
continue;
}
}
}
static void
puntfp(Prog *p)
{
USED(p);
/* floating point - punt for now */
curtext->reg = NREG; /* ARM */
curtext->from.sym->thumb = 0;
thumb = 0;
// print("%s: generating ARM code (contains floating point ops %d)\n", curtext->from.sym->name, p->line);
}
Prog*
appendp(Prog *q)
{
Prog *p;
p = prg();
p->link = q->link;
q->link = p;
p->line = q->line;
return p;
}