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This commit is contained in:
Pavlas, Zdenek 2016-10-03 03:14:34 -07:00
parent da63695cf3
commit f795e1be83
1 changed files with 51 additions and 23 deletions
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74
tccgen.c
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@ -4888,6 +4888,52 @@ static int case_cmp(const void *pa, const void *pb)
return a < b ? -1 : a > b;
}
static void gcase(struct case_t **base, int len, int case_reg, int *bsym)
{
struct case_t *p;
int e;
if (len <= 4) {
while (len--) {
p = *base++;
vseti(case_reg, 0);
vpushi(p->v2);
if (p->v1 == p->v2) {
gen_op(TOK_EQ);
gtst_addr(0, p->sym);
} else {
gen_op(TOK_LE);
e = gtst(1, 0);
vseti(case_reg, 0);
vpushi(p->v1);
gen_op(TOK_GE);
gtst_addr(0, p->sym);
gsym(e);
}
}
} else {
p = base[len/2];
/* mid */
vseti(case_reg, 0);
vpushi(p->v2);
gen_op(TOK_LE);
e = gtst(1, 0);
vseti(case_reg, 0);
vpushi(p->v1);
gen_op(TOK_GE);
gtst_addr(0, p->sym);
/* left */
gcase(base, len/2, case_reg, bsym);
if (cur_switch->def_sym)
gjmp_addr(cur_switch->def_sym);
else
*bsym = gjmp(*bsym);
/* right */
gsym(e);
e = len/2 + 1;
gcase(base + e, len - e, case_reg, bsym);
}
}
static void block(int *bsym, int *csym, int is_expr)
{
int a, b, c, d;
@ -5166,35 +5212,17 @@ static void block(int *bsym, int *csym, int is_expr)
sw.p = NULL; sw.n = 0; sw.def_sym = 0;
saved = cur_switch;
cur_switch = &sw; block(&a, csym, 0);
cur_switch = saved;
a = gjmp(a); /* add implicit break */
/* case lookup */
gsym(b);
qsort(sw.p, sw.n, sizeof(void*), case_cmp);
for (b = 0; b < sw.n; b++) {
int v = sw.p[b]->v1;
if (b && v <= d)
for (b = 1; b < sw.n; b++)
if (sw.p[b - 1]->v2 >= sw.p[b]->v1)
tcc_error("duplicate case value");
d = sw.p[b]->v2;
vseti(c, 0);
vpushi(v);
if (v == d) {
gen_op(TOK_EQ);
gtst_addr(0, sw.p[b]->sym);
} else {
int e;
gen_op(TOK_GE);
e = gtst(1, 0);
vseti(c, 0);
vpushi(d);
gen_op(TOK_LE);
gtst_addr(0, sw.p[b]->sym);
gsym(e);
}
}
gcase(sw.p, sw.n, c, &a);
if (sw.def_sym)
gjmp_addr(sw.def_sym);
cur_switch = saved;
/* break label */
gsym(a);
} else