ref: a70b93a356662355214f5405edda066786f6dd03
dir: /sys/src/cmd/7l/pass.c/
#include "l.h"
vlong
atolwhex(char *s)
{
vlong n;
int f;
n = 0;
f = 0;
while(*s == ' ' || *s == '\t')
s++;
if(*s == '-' || *s == '+') {
if(*s++ == '-')
f = 1;
while(*s == ' ' || *s == '\t')
s++;
}
if(s[0]=='0' && s[1]){
if(s[1]=='x' || s[1]=='X'){
s += 2;
for(;;){
if(*s >= '0' && *s <= '9')
n = n*16 + *s++ - '0';
else if(*s >= 'a' && *s <= 'f')
n = n*16 + *s++ - 'a' + 10;
else if(*s >= 'A' && *s <= 'F')
n = n*16 + *s++ - 'A' + 10;
else
break;
}
} else
while(*s >= '0' && *s <= '7')
n = n*8 + *s++ - '0';
} else
while(*s >= '0' && *s <= '9')
n = n*10 + *s++ - '0';
if(f)
n = -n;
return n;
}
vlong
rnd(vlong v, long r)
{
long c;
if(r <= 0)
return v;
v += r - 1;
c = v % r;
if(c < 0)
c += r;
v -= c;
return v;
}
void
dodata(void)
{
int i, t;
Sym *s;
Prog *p;
long orig, v;
if(debug['v'])
Bprint(&bso, "%5.2f dodata\n", cputime());
Bflush(&bso);
for(p = datap; p != P; p = p->link) {
s = p->from.sym;
if(p->as == ADYNT || p->as == AINIT)
s->value = dtype;
if(s->type == SBSS)
s->type = SDATA;
if(s->type != SDATA)
diag("initialize non-data (%d): %s\n%P",
s->type, s->name, p);
v = p->from.offset + p->reg;
if(v > s->value)
diag("initialize bounds (%lld): %s\n%P",
(vlong)s->value, s->name, p);
}
if(debug['t']) {
/*
* pull out string constants
*/
for(p = datap; p != P; p = p->link) {
s = p->from.sym;
if(p->to.type == D_SCONST)
s->type = SSTRING;
}
}
/*
* pass 1
* assign 'small' variables to data segment
* (rationale is that data segment is more easily
* addressed through offset on REGSB)
*/
orig = 0;
for(i=0; i<NHASH; i++)
for(s = hash[i]; s != S; s = s->link) {
t = s->type;
if(t != SDATA && t != SBSS)
continue;
v = s->value;
if(v == 0) {
diag("%s: no size", s->name);
v = 1;
}
v = rnd(v, 4);
s->value = v;
if(v > MINSIZ)
continue;
if(v >= 16)
orig = rnd(orig, 16);
else if(v >= 8)
orig = rnd(orig, 8);
s->value = orig;
orig += v;
s->type = SDATA1;
}
/*
* pass 2
* assign large 'data' variables to data segment
*/
for(i=0; i<NHASH; i++)
for(s = hash[i]; s != S; s = s->link) {
t = s->type;
if(t != SDATA) {
if(t == SDATA1)
s->type = SDATA;
continue;
}
v = s->value;
if(v >= 16)
orig = rnd(orig, 16);
else if(v >= 8)
orig = rnd(orig, 8);
s->value = orig;
orig += v;
}
while(orig & 7)
orig++;
datsize = orig;
/*
* pass 3
* everything else to bss segment
*/
for(i=0; i<NHASH; i++)
for(s = hash[i]; s != S; s = s->link) {
if(s->type != SBSS)
continue;
v = s->value;
if(v >= 16)
orig = rnd(orig, 16);
else if(v >= 8)
orig = rnd(orig, 8);
s->value = orig;
orig += v;
}
while(orig & 7)
orig++;
bsssize = orig-datsize;
xdefine("setSB", SDATA, 0L);
xdefine("bdata", SDATA, 0L);
xdefine("edata", SDATA, datsize);
xdefine("end", SBSS, datsize+bsssize);
xdefine("etext", STEXT, 0L);
}
Prog*
brchain(Prog *p)
{
int i;
for(i=0; i<20; i++) {
if(p == P || !isbranch(p->as))
return p;
p = p->cond;
}
return P;
}
void
follow(void)
{
if(debug['v'])
Bprint(&bso, "%5.2f follow\n", cputime());
Bflush(&bso);
firstp = prg();
lastp = firstp;
xfol(textp);
firstp = firstp->link;
lastp->link = P;
}
void
xfol(Prog *p)
{
Prog *q, *r;
int a, i;
loop:
if(p == P)
return;
a = p->as;
if(a == ATEXT)
curtext = p;
if(isbranch(a)) {
q = p->cond;
if(q != P) {
p->mark |= FOLL;
p = q;
if(!(p->mark & FOLL))
goto loop;
}
}
if(p->mark & FOLL) {
for(i=0,q=p; i<4; i++,q=q->link) {
if(q == lastp)
break;
a = q->as;
if(a == ANOP) {
i--;
continue;
}
if(isbranch(a) || isreturn(a))
goto copy;
if(q->cond == nil || (q->cond->mark&FOLL))
continue;
if(a != ABEQ && a != ABNE)
continue;
copy:
for(;;) {
r = prg();
*r = *p;
if(!(r->mark&FOLL))
print("cant happen 1\n");
r->mark |= FOLL;
if(p != q) {
p = p->link;
lastp->link = r;
lastp = r;
continue;
}
lastp->link = r;
lastp = r;
if(isbranch(a) || isreturn(a))
return;
r->as = a == ABNE? ABEQ: ABNE;
r->cond = p->link;
r->link = p->cond;
if(!(r->link->mark&FOLL))
xfol(r->link);
if(!(r->cond->mark&FOLL))
print("cant happen 2\n");
return;
}
}
a = branchop();
q = prg();
q->as = a;
q->line = p->line;
q->to.type = D_BRANCH;
q->to.offset = p->pc;
q->cond = p;
p = q;
}
p->mark |= FOLL;
lastp->link = p;
lastp = p;
if(isbranch(a) || isreturn(a))
return;
if(p->cond != P)
if(!iscall(a) && p->link != P) {
q = brchain(p->link);
if(canfollow(a))
if(q != P && (q->mark&FOLL)) {
p->as = relinv(a);
p->link = p->cond;
p->cond = q;
}
xfol(p->link);
q = brchain(p->cond);
if(q == P)
q = p->cond;
if(q->mark&FOLL) {
p->cond = q;
return;
}
p = q;
goto loop;
}
p = p->link;
goto loop;
}
void
patch(void)
{
long c, vexit;
Prog *p, *q;
Sym *s;
int a;
if(debug['v'])
Bprint(&bso, "%5.2f patch\n", cputime());
Bflush(&bso);
mkfwd();
s = lookup("exit", 0);
vexit = s->value;
for(p = firstp; p != P; p = p->link) {
a = p->as;
if(a == ATEXT)
curtext = p;
if((iscall(a) || isbranch(a) || isreturn(a)) &&
p->to.type != D_BRANCH && p->to.sym != S) {
s = p->to.sym;
switch(s->type) {
default:
diag("undefined: %s\n%P", s->name, p);
s->type = STEXT;
s->value = vexit;
break;
case STEXT:
p->to.offset = s->value;
break;
case SUNDEF:
if(!iscall(p->as))
diag("help: SUNDEF in AB || ARET");
p->to.offset = 0;
p->cond = UP;
break;
}
p->to.type = D_BRANCH;
}
if(p->cond == UP)
continue;
if(p->to.type == D_BRANCH)
c = p->to.offset;
else if(p->from.type == D_BRANCH)
c = p->from.offset;
else
continue;
for(q = firstp; q != P;) {
if(q->forwd != P)
if(c >= q->forwd->pc) {
q = q->forwd;
continue;
}
if(c == q->pc)
break;
q = q->link;
}
if(q == P) {
diag("branch out of range %ld\n%P", c, p);
p->to.type = D_NONE;
}
p->cond = q;
}
for(p = firstp; p != P; p = p->link) {
if(p->as == ATEXT)
curtext = p;
if(p->cond != P && p->cond != UP) {
p->cond = brloop(p->cond);
if(p->cond != P){
if(p->to.type == D_BRANCH)
p->to.offset = p->cond->pc;
if(p->from.type == D_BRANCH)
p->from.offset = p->cond->pc;
}
}
}
}
#define LOG 6
void
mkfwd(void)
{
Prog *p;
long dwn[LOG], cnt[LOG], i;
Prog *lst[LOG];
for(i=0; i<LOG; i++) {
if(i == 0)
cnt[i] = 1; else
cnt[i] = LOG * cnt[i-1];
dwn[i] = 1;
lst[i] = P;
}
i = 0;
for(p = firstp; p != P; p = p->link) {
if(p->as == ATEXT)
curtext = p;
i--;
if(i < 0)
i = LOG-1;
p->forwd = P;
dwn[i]--;
if(dwn[i] <= 0) {
dwn[i] = cnt[i];
if(lst[i] != P)
lst[i]->forwd = p;
lst[i] = p;
}
}
}
Prog*
brloop(Prog *p)
{
Prog *q;
int c;
for(c=0; p!=P;) {
if(!isbranch(p->as))
return p;
q = p->cond;
if(q <= p) {
c++;
if(q == p || c > 5000)
break;
}
p = q;
}
return P;
}
void
undef(void)
{
int i;
Sym *s;
for(i=0; i<NHASH; i++)
for(s = hash[i]; s != S; s = s->link)
if(s->type == SXREF)
diag("%s: not defined", s->name);
}