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simplified js_bigint_from_float64()

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Fabrice Bellard 2025-03-19 13:56:10 +01:00
parent 7399069dc1
commit 131408fa07
1 changed files with 25 additions and 33 deletions
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58
quickjs.c
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@ -10192,11 +10192,31 @@ static JSBigInt *js_bigint_new(JSContext *ctx, int len)
static JSBigInt *js_bigint_set_si(JSBigIntBuf *buf, js_slimb_t a) static JSBigInt *js_bigint_set_si(JSBigIntBuf *buf, js_slimb_t a)
{ {
JSBigInt *r = (JSBigInt *)buf->big_int_buf; JSBigInt *r = (JSBigInt *)buf->big_int_buf;
r->header.ref_count = 0; /* fail safe */
r->len = 1; r->len = 1;
r->tab[0] = a; r->tab[0] = a;
return r; return r;
} }
static JSBigInt *js_bigint_set_si64(JSBigIntBuf *buf, int64_t a)
{
#if JS_LIMB_BITS == 64
return js_bigint_set_si(buf, a);
#else
JSBigInt *r = (JSBigInt *)buf->big_int_buf;
r->header.ref_count = 0; /* fail safe */
if (a >= INT32_MIN && a <= INT32_MAX) {
r->len = 1;
r->tab[0] = a;
} else {
r->len = 2;
r->tab[0] = a;
r->tab[1] = a >> JS_LIMB_BITS;
}
return r;
#endif
}
/* val must be a short big int */ /* val must be a short big int */
static JSBigInt *js_bigint_set_short(JSBigIntBuf *buf, JSValueConst val) static JSBigInt *js_bigint_set_short(JSBigIntBuf *buf, JSValueConst val)
{ {
@ -10862,7 +10882,7 @@ static JSBigInt *js_bigint_from_float64(JSContext *ctx, int *pres, double a1)
int sgn, e, shift; int sgn, e, shift;
uint64_t mant; uint64_t mant;
JSBigIntBuf buf; JSBigIntBuf buf;
JSBigInt *r, *r1; JSBigInt *r;
sgn = a >> 63; sgn = a >> 63;
e = (a >> 52) & ((1 << 11) - 1); e = (a >> 52) & ((1 << 11) - 1);
@ -10895,40 +10915,12 @@ static JSBigInt *js_bigint_from_float64(JSContext *ctx, int *pres, double a1)
} else { } else {
e -= 52; e -= 52;
} }
if (sgn)
mant = -mant;
/* the integer is mant*2^e */ /* the integer is mant*2^e */
r = (JSBigInt *)buf.big_int_buf; r = js_bigint_set_si64(&buf, (int64_t)mant);
#if JS_LIMB_BITS == 64
r->len = 1;
r->tab[0] = mant;
#else
if (mant <= INT32_MAX) {
r->len = 1;
r->tab[0] = mant;
} else {
r->len = 2;
r->tab[0] = mant;
r->tab[1] = mant >> 32;
}
#endif
/* XXX: optimize */
if (sgn) {
r = js_bigint_neg(ctx, r);
if (!r)
goto fail;
r1 = js_bigint_shl(ctx, r, e);
js_free(ctx, r);
if (!r1)
goto fail;
r = r1;
} else {
r = js_bigint_shl(ctx, r, e);
}
*pres = 0; *pres = 0;
return r; return js_bigint_shl(ctx, r, e);
fail:
*pres = 0;
return NULL;
} }
/* return -1, 0, 1 or (2) (unordered) */ /* return -1, 0, 1 or (2) (unordered) */