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wip on a simpler slot handling

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This commit is contained in:
Quentin Carbonneaux 2015-09-29 17:23:55 -04:00
parent fdbff25a61
commit 5e5d0a1e99
3 changed files with 52 additions and 71 deletions
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88
lisc/isel.c
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@ -341,60 +341,6 @@ seljmp(Blk *b, Fn *fn)
b->jmp.type = JXJc + Cne;
}
int
slota(int sz, int al /* log2 */, int *sa)
{
int j, k, s, l, a, ret;
a = 1 << al;
l = sz;
if (l > a) {
/* for large slots, we just
* tack them on the next max
* alignment slot available
* todo, could sophisticate
*/
l = (l + a-1) & ~(a-1);
s = sa[NAlign-1] + l;
ret = s;
for (j=0, k=1; j<NAlign; j++, k*=2) {
l = (l + k-1) & ~(k-1);
sa[j] = sa[NAlign-1] + l;
}
} else {
j = al;
s = sa[j] + a;
ret = s;
Shift:
if (j < NAlign-1 && s < sa[j+1])
/* ........-----------...
* ^ ^ ^
* sa[j] sa[j]+a sa[j+1]
*
* we have to skip to the
* next large whole
*/
s = sa[j+1];
for (k=0; k<=j; k++)
/* move all smaller holes
* that we contain with us
*/
if (sa[k] == sa[j])
sa[k] = s;
if (j < NAlign-1 && s > sa[j+1]) {
/* we were in a bigger hole,
* it needs to shift further
*/
s = sa[++j] + (a *= 2);
goto Shift;
}
}
return ret;
}
typedef struct AClass AClass;
struct AClass {
@ -693,8 +639,8 @@ isel(Fn *fn)
int64_t sz;
for (n=Tmp0; n<fn->ntmp; n++)
fn->tmp[n].spill = 0;
memset(fn->svec, 0, sizeof fn->svec);
fn->tmp[n].spill = -1;
fn->stk0 = 0;
/* lower arguments */
for (b=fn->start, i=b->ins; i-b->ins < b->nins; i++)
@ -735,20 +681,22 @@ isel(Fn *fn)
}
/* assign slots to fast allocs */
for (b=fn->start, i=b->ins; i-b->ins < b->nins; i++)
if (OAlloc <= i->op && i->op <= OAlloc1) {
if (rtype(i->arg[0]) != RCon)
break;
sz = fn->con[i->arg[0].val].val;
if (sz < 0 || sz >= INT_MAX-3)
diag("isel: invalid alloc size");
n = 16 / (1 << (NAlign-1));
sz = (sz + n-1) / n;
al = i->op - OAlloc;
s = slota(sz, al, fn->svec);
fn->tmp[i->to.val].spill = s;
i->to = R;
}
b = fn->start;
assert(NAlign == 3 && "change n=4 and sz /= 4 below");
for (al=OAlloc, n=4; al<=OAlloc1; al++, n*=2)
for (i=b->ins; i-b->ins < b->nins; i++)
if (i->op == al) {
if (rtype(i->arg[0]) != RCon)
break;
sz = fn->con[i->arg[0].val].val;
if (sz < 0 || sz >= INT_MAX-3)
diag("isel: invalid alloc size");
sz = (sz + n-1) & -n;
sz /= 4;
fn->tmp[i->to.val].spill = fn->stk0;
fn->stk0 -= sz;
i->to = R;
}
for (b=fn->start; b; b=b->link) {
for (sb=(Blk*[3]){b->s1, b->s2, 0}; *sb; sb++)