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major lifting: get rid of RReg

Browse source 
I've been septic since I introduced it, this commit
proves that it costs more than it helps.  I've also fixed
a bad bug in rega() where I alloc'ed the wrong size for
internal arrays.  Enums now have names so I can use them
to cast in gdb to get the name corresponding to a constant.
This commit is contained in:
Quentin Carbonneaux 2015-08-13 16:10:54 -04:00
parent 78bf28f56e
commit 5fc8104e00
8 changed files with 97 additions and 142 deletions
Download patch file Download diff file Expand all files Collapse all files

83
lisc/rega.c
View file

@ -31,13 +31,14 @@ rfind(RMap *m, int t)
static Ref
reg(int r, int t)
{
assert(r < Tmp0);
switch (tmp[t].type) {
default:
assert(!"invalid temporary");
diag("rega: invalid temporary");
case TWord:
return REG(RWORD(r));
return TMP(RWORD(r));
case TLong:
return REG(r);
return TMP(r);
}
}
@ -75,6 +76,10 @@ ralloc(RMap *m, int t)
static int x;
int n, r;
if (t < Tmp0) {
BSET(m->br, t);
return TMP(t);
}
if (BGET(m->bt, t)) {
r = rfind(m, t);
assert(r != -1);
@ -100,6 +105,12 @@ rfree(RMap *m, int t)
{
int i, r;
if (t < Tmp0) {
t = RBASE(t);
assert(BGET(m->br, t));
BCLR(m->br, t);
return t;
}
if (!BGET(m->bt, t))
return -1;
for (i=0; m->t[i] != t; i++)
@ -194,6 +205,12 @@ pmgen()
free(status);
}
static int
isreg(Ref r)
{
return rtype(r) == RTmp && r.val < Tmp0;
}
static Ins *
dopm(Blk *b, Ins *i, RMap *m)
{
@ -203,7 +220,7 @@ dopm(Blk *b, Ins *i, RMap *m)
npm = 0;
i1 = i+1;
if (rtype(i->to) == RReg)
if (isreg(i->to))
for (;; i--) {
r = RBASE(i->to.val);
rt = i->arg[0];
@ -215,13 +232,12 @@ dopm(Blk *b, Ins *i, RMap *m)
pmadd(rt, i->to);
if (i==b->ins
|| (i-1)->op!=OCopy
|| rtype((i-1)->to) != RReg)
|| isreg((i-1)->to))
break;
}
else if (rtype(i->arg[0]) == RReg)
else if (isreg(i->arg[0]))
for (;; i--) {
r = RBASE(i->arg[0].val);
assert(req(i->to, R) || i->to.type == RTmp);
if (req(i->to, R)) {
if (BGET(m->br, r)) {
for (n=0; m->r[n] != r; n++)
@ -239,7 +255,7 @@ dopm(Blk *b, Ins *i, RMap *m)
BSET(m->br, r);
if (i==b->ins
|| (i-1)->op!=OCopy
|| rtype((i-1)->arg[0]) != RReg)
|| isreg((i-1)->arg[0]))
break;
}
else
@ -273,21 +289,19 @@ rega(Fn *fn)
Ref src, dst;
tmp = fn->tmp;
end = alloc(fn->ntmp * sizeof end[0]);
beg = alloc(fn->ntmp * sizeof beg[0]);
end = alloc(fn->nblk * sizeof end[0]);
beg = alloc(fn->nblk * sizeof beg[0]);
/* 1. gross hinting setup */
for (t=0; t<fn->ntmp; t++)
for (t=Tmp0; t<fn->ntmp; t++)
tmp[t].hint = -1;
for (b=fn->start; b; b=b->link)
for (i=b->ins; i-b->ins < b->nins; i++) {
if (i->op != OCopy)
continue;
if (rtype(i->arg[0]) == RTmp
&& rtype(i->to) == RReg)
if (rtype(i->arg[0]) == RTmp && isreg(i->to))
tmp[i->arg[0].val].hint = RBASE(i->to.val);
if (rtype(i->to) == RTmp
&& rtype(i->arg[0]) == RReg)
if (rtype(i->to) == RTmp && isreg(i->arg[0]))
tmp[i->to.val].hint = RBASE(i->arg[0].val);
}
@ -309,48 +323,38 @@ rega(Fn *fn)
* successor
*/
if (b1 != b)
for (t=0; t<fn->ntmp; t++)
for (t=Tmp0; t<fn->ntmp; t++)
if (BGET(b->out, t))
if ((r = rfind(&beg[b1->id], t)) != -1)
radd(&cur, t, r);
for (x=0; x<2; x++)
for (t=0; t<fn->ntmp; t++)
for (t=Tmp0; t<fn->ntmp; t++)
if (x==1 || tmp[t].hint!=-1)
if (BGET(b->out, t))
if (!BGET(cur.bt, t))
ralloc(&cur, t);
/* process instructions */
end[n] = cur;
assert(rtype(b->jmp.arg) != RReg);
if (rtype(b->jmp.arg) == RTmp)
b->jmp.arg = ralloc(&cur, b->jmp.arg.val);
for (i=&b->ins[b->nins]; i!=b->ins;) {
i--;
if (i->op == OCopy /* par. moves are special */
&& (rtype(i->arg[0]) == RReg || rtype(i->to) == RReg)) {
&& (isreg(i->arg[0]) || isreg(i->to))) {
i = dopm(b, i, &cur);
continue;
}
switch (rtype(i->to)) {
default:
assert(!"unhandled destination");
case RTmp:
if (!req(i->to, R)) {
assert(rtype(i->to) == RTmp);
r = rfree(&cur, i->to.val);
if (r == -1) {
*i = (Ins){ONop, R, {R, R}};
continue;
}
i->to = reg(r, i->to.val);
break;
case RReg:
r = RBASE(i->to.val);
assert(BGET(cur.br, r));
BCLR(cur.br, r);
break;
case -1:;
if (i->to.val >= Tmp0)
i->to = reg(r, i->to.val);
}
switch (rtype(i->arg[0])) {
case RTmp:
if (rtype(i->arg[0]) == RTmp) {
/* <arch>
* on Intel, we attempt to
* use the same register
@ -361,19 +365,10 @@ rega(Fn *fn)
if (tmp[t].hint == -1 && r)
tmp[t].hint = r;
i->arg[0] = ralloc(&cur, t);
break;
case RReg:
BSET(cur.br, RBASE(i->arg[0].val));
break;
}
switch (rtype(i->arg[1])) {
case RTmp:
if (rtype(i->arg[1]) == RTmp) {
t = i->arg[1].val;
i->arg[1] = ralloc(&cur, t);
break;
case RReg:
BSET(cur.br, RBASE(i->arg[1].val));
break;
}
}
b->in = cur.bt;
@ -413,7 +408,7 @@ rega(Fn *fn)
src = rref(&end[b->id], src.val);
pmadd(src, dst);
}
for (t=0; t<fn->ntmp; t++)
for (t=Tmp0; t<fn->ntmp; t++)
if (BGET(s->in, t)) {
src = rref(&end[b->id], t);
dst = rref(&beg[s->id], t);