shithub: libmujs

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Add fast integer special case in jsV_numbertostring.

Also fix js_itoa to support signed integers.

--- a/jsi.h

+++ b/jsi.h

@@ -11,6 +11,7 @@

 #include <setjmp.h>

 #include <math.h>

 #include <float.h>

+#include <limits.h>

 /* Microsoft Visual C */

 #ifdef _MSC_VER

--- a/jsvalue.c

+++ b/jsvalue.c

@@ -128,10 +128,17 @@

 	}

 }

-const char *js_itoa(char *out, int a)

+const char *js_itoa(char *out, int v)

 {

 	char buf[32], *s = out;

+	unsigned int a;

 	int i = 0;

+	if (v < 0) {

+		a = -v;

+		*s++ = '-';

+	} else {

+		a = v;

+	}

 	while (a) {

 		buf[i++] = (a % 10) + '0';

 		a /= 10;

@@ -222,9 +229,18 @@

 	char digits[32], *p = buf, *s = digits;

 	int exp, ndigits, point;

+	if (f == 0) return "0";

 	if (isnan(f)) return "NaN";

 	if (isinf(f)) return f < 0 ? "-Infinity" : "Infinity";

-	if (f == 0) return "0";

+

+	/* Fast case for integers. This only works assuming all integers can be

+	 * exactly represented by a float. This is true for 32-bit integers and

+	 * 64-bit floats. */

+	if (f >= INT_MIN && f <= INT_MAX) {

+		int i = (int)f;

+		if ((double)i == f)

+			return js_itoa(buf, i);

+	}

 	ndigits = js_grisu2(f, digits, &exp);

 	point = ndigits + exp;