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wip on new stack slots (emit, spill)

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This commit is contained in:
Quentin Carbonneaux 2015-09-29 22:25:49 -04:00
parent ae158a5c40
commit e2174da2f1
6 changed files with 59 additions and 35 deletions
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46
lisc/spill.c
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@ -143,7 +143,9 @@ extern Ins insb[NIns], *curi; /* shared work buffer */
static Bits *f; /* temps to prioritize in registers (for tcmp1) */
static Tmp *tmp; /* current temporaries (for tcmpX) */
static int ntmp; /* current # of temps (for limit) */
static int *svec; /* free slots vector */
static int locs; /* stack size used by locals */
static int slot4; /* next slot of 4 bytes */
static int slot8; /* ditto, 8 bytes */
static int
tcmp0(const void *pa, const void *pb)
@ -168,11 +170,28 @@ slot(int t)
if (t < Tmp0)
diag("spill: cannot spill register");
s = tmp[t].spill;
if (!s) {
if (tmp[t].wide)
s = slota(2, 1, svec);
else
s = slota(1, 0, svec);
if (s == -1) {
assert(NAlign == 3);
/* nice logic to pack stack slots
* on demand, there can be only
* one hole and slot4 points to it
*
* invariant: slot4 <= slot8
*/
if (tmp[t].wide) {
s = slot8;
if (slot4 == slot8)
slot4 += 2;
slot8 += 2;
} else {
s = slot4;
if (slot4 == slot8) {
slot8 += 2;
slot4 += 1;
} else
slot4 = slot8;
}
s += locs;
tmp[t].spill = s;
}
return SLOT(s);
@ -312,9 +331,11 @@ spill(Fn *fn)
int j, s;
Phi *p;
svec = fn->svec;
tmp = fn->tmp;
ntmp = fn->ntmp;
locs = fn->slot;
slot4 = 0;
slot8 = 0;
assert(ntmp < NBit*BITS);
for (b=fn->start; b; b=b->link) {
@ -382,7 +403,7 @@ spill(Fn *fn)
i = dopm(b, i, &v);
continue;
}
s = 0;
s = -1;
w = (Bits){{0}};
if (!req(i->to, R)) {
assert(rtype(i->to) == RTmp);
@ -400,7 +421,7 @@ spill(Fn *fn)
if (!j && rtype(i->arg[1]) == RTmp)
BSET(w, i->arg[1].val);
j -= setloc(&i->arg[1], &v, &w);
if (s)
if (s != -1)
store(i->to, s);
emit(*i);
}
@ -411,7 +432,7 @@ spill(Fn *fn)
if (BGET(v, t)) {
BCLR(v, t);
s = tmp[t].spill;
if (s)
if (s != -1)
store(p->to, s);
} else
p->to = slot(p->to.val);
@ -422,4 +443,9 @@ spill(Fn *fn)
b->ins = alloc(b->nins * sizeof(Ins));
memcpy(b->ins, curi, b->nins * sizeof(Ins));
}
/* align the locals to a 16 byte boundary */
assert(NAlign == 3);
slot8 += slot8 & 3;
fn->slot += slot8;
}