diff -r 000000000000 -r 6474c204b198 js/src/jsnum.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jsnum.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,333 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jsnum_h
+#define jsnum_h
+
+#include "mozilla/FloatingPoint.h"
+
+#include "NamespaceImports.h"
+
+#include "vm/NumericConversions.h"
+
+namespace js {
+
+class StringBuffer;
+
+extern bool
+InitRuntimeNumberState(JSRuntime *rt);
+
+#if !EXPOSE_INTL_API
+extern void
+FinishRuntimeNumberState(JSRuntime *rt);
+#endif
+
+} /* namespace js */
+
+/* Initialize the Number class, returning its prototype object. */
+extern JSObject *
+js_InitNumberClass(JSContext *cx, js::HandleObject obj);
+
+/*
+ * String constants for global function names, used in jsapi.c and jsnum.c.
+ */
+extern const char js_isNaN_str[];
+extern const char js_isFinite_str[];
+extern const char js_parseFloat_str[];
+extern const char js_parseInt_str[];
+
+class JSAtom;
+
+namespace js {
+
+/*
+ * When base == 10, this function implements ToString() as specified by
+ * ECMA-262-5 section 9.8.1; but note that it handles integers specially for
+ * performance.  See also js::NumberToCString().
+ */
+template <js::AllowGC allowGC>
+extern JSString *
+NumberToString(js::ThreadSafeContext *cx, double d);
+
+extern JSAtom *
+NumberToAtom(js::ExclusiveContext *cx, double d);
+
+template <AllowGC allowGC>
+extern JSFlatString *
+Int32ToString(ThreadSafeContext *cx, int32_t i);
+
+extern JSAtom *
+Int32ToAtom(ExclusiveContext *cx, int32_t si);
+
+/*
+ * Convert an integer or double (contained in the given value) to a string and
+ * append to the given buffer.
+ */
+extern bool JS_FASTCALL
+NumberValueToStringBuffer(JSContext *cx, const Value &v, StringBuffer &sb);
+
+/* Same as js_NumberToString, different signature. */
+extern JSFlatString *
+NumberToString(JSContext *cx, double d);
+
+extern JSFlatString *
+IndexToString(JSContext *cx, uint32_t index);
+
+/*
+ * Usually a small amount of static storage is enough, but sometimes we need
+ * to dynamically allocate much more.  This struct encapsulates that.
+ * Dynamically allocated memory will be freed when the object is destroyed.
+ */
+struct ToCStringBuf
+{
+    /*
+     * The longest possible result that would need to fit in sbuf is
+     * (-0x80000000).toString(2), which has length 33.  Longer cases are
+     * possible, but they'll go in dbuf.
+     */
+    static const size_t sbufSize = 34;
+    char sbuf[sbufSize];
+    char *dbuf;
+
+    ToCStringBuf();
+    ~ToCStringBuf();
+};
+
+/*
+ * Convert a number to a C string.  When base==10, this function implements
+ * ToString() as specified by ECMA-262-5 section 9.8.1.  It handles integral
+ * values cheaply.  Return nullptr if we ran out of memory.  See also
+ * js_NumberToCString().
+ */
+extern char *
+NumberToCString(JSContext *cx, ToCStringBuf *cbuf, double d, int base = 10);
+
+/*
+ * The largest positive integer such that all positive integers less than it
+ * may be precisely represented using the IEEE-754 double-precision format.
+ */
+const double DOUBLE_INTEGRAL_PRECISION_LIMIT = uint64_t(1) << 53;
+
+/*
+ * Parse a decimal number encoded in |chars|.  The decimal number must be
+ * sufficiently small that it will not overflow the integrally-precise range of
+ * the double type -- that is, the number will be smaller than
+ * DOUBLE_INTEGRAL_PRECISION_LIMIT
+ */
+extern double
+ParseDecimalNumber(const JS::TwoByteChars chars);
+
+/*
+ * Compute the positive integer of the given base described immediately at the
+ * start of the range [start, end) -- no whitespace-skipping, no magical
+ * leading-"0" octal or leading-"0x" hex behavior, no "+"/"-" parsing, just
+ * reading the digits of the integer.  Return the index one past the end of the
+ * digits of the integer in *endp, and return the integer itself in *dp.  If
+ * base is 10 or a power of two the returned integer is the closest possible
+ * double; otherwise extremely large integers may be slightly inaccurate.
+ *
+ * If [start, end) does not begin with a number with the specified base,
+ * *dp == 0 and *endp == start upon return.
+ */
+extern bool
+GetPrefixInteger(ThreadSafeContext *cx, const jschar *start, const jschar *end, int base,
+                 const jschar **endp, double *dp);
+
+/*
+ * This is like GetPrefixInteger, but only deals with base 10, and doesn't have
+ * and |endp| outparam.  It should only be used when the jschars are known to
+ * only contain digits.
+ */
+extern bool
+GetDecimalInteger(ExclusiveContext *cx, const jschar *start, const jschar *end, double *dp);
+
+extern bool
+StringToNumber(ThreadSafeContext *cx, JSString *str, double *result);
+
+/* ES5 9.3 ToNumber, overwriting *vp with the appropriate number value. */
+MOZ_ALWAYS_INLINE bool
+ToNumber(JSContext *cx, JS::MutableHandleValue vp)
+{
+    if (vp.isNumber())
+        return true;
+    double d;
+    extern JS_PUBLIC_API(bool) ToNumberSlow(JSContext *cx, Value v, double *dp);
+    if (!ToNumberSlow(cx, vp, &d))
+        return false;
+
+    vp.setNumber(d);
+    return true;
+}
+
+bool
+num_parseInt(JSContext *cx, unsigned argc, Value *vp);
+
+}  /* namespace js */
+
+/*
+ * Similar to strtod except that it replaces overflows with infinities of the
+ * correct sign, and underflows with zeros of the correct sign.  Guaranteed to
+ * return the closest double number to the given input in dp.
+ *
+ * Also allows inputs of the form [+|-]Infinity, which produce an infinity of
+ * the appropriate sign.  The case of the "Infinity" string must match exactly.
+ * If the string does not contain a number, set *ep to s and return 0.0 in dp.
+ * Return false if out of memory.
+ */
+extern bool
+js_strtod(js::ThreadSafeContext *cx, const jschar *s, const jschar *send,
+          const jschar **ep, double *dp);
+
+extern bool
+js_num_toString(JSContext *cx, unsigned argc, js::Value *vp);
+
+extern bool
+js_num_valueOf(JSContext *cx, unsigned argc, js::Value *vp);
+
+namespace js {
+
+static MOZ_ALWAYS_INLINE bool
+ValueFitsInInt32(const Value &v, int32_t *pi)
+{
+    if (v.isInt32()) {
+        *pi = v.toInt32();
+        return true;
+    }
+    return v.isDouble() && mozilla::NumberIsInt32(v.toDouble(), pi);
+}
+
+/*
+ * Returns true if the given value is definitely an index: that is, the value
+ * is a number that's an unsigned 32-bit integer.
+ *
+ * This method prioritizes common-case speed over accuracy in every case.  It
+ * can produce false negatives (but not false positives): some values which are
+ * indexes will be reported not to be indexes by this method.  Users must
+ * consider this possibility when using this method.
+ */
+static MOZ_ALWAYS_INLINE bool
+IsDefinitelyIndex(const Value &v, uint32_t *indexp)
+{
+    if (v.isInt32() && v.toInt32() >= 0) {
+        *indexp = v.toInt32();
+        return true;
+    }
+
+    int32_t i;
+    if (v.isDouble() && mozilla::NumberIsInt32(v.toDouble(), &i) && i >= 0) {
+        *indexp = uint32_t(i);
+        return true;
+    }
+
+    return false;
+}
+
+/* ES5 9.4 ToInteger. */
+static inline bool
+ToInteger(JSContext *cx, HandleValue v, double *dp)
+{
+    if (v.isInt32()) {
+        *dp = v.toInt32();
+        return true;
+    }
+    if (v.isDouble()) {
+        *dp = v.toDouble();
+    } else {
+        extern JS_PUBLIC_API(bool) ToNumberSlow(JSContext *cx, Value v, double *dp);
+        if (!ToNumberSlow(cx, v, dp))
+            return false;
+    }
+    *dp = ToInteger(*dp);
+    return true;
+}
+
+inline bool
+SafeAdd(int32_t one, int32_t two, int32_t *res)
+{
+    // Use unsigned for the 32-bit operation since signed overflow gets
+    // undefined behavior.
+    *res = uint32_t(one) + uint32_t(two);
+    int64_t ores = (int64_t)one + (int64_t)two;
+    return ores == (int64_t)*res;
+}
+
+inline bool
+SafeSub(int32_t one, int32_t two, int32_t *res)
+{
+    *res = uint32_t(one) - uint32_t(two);
+    int64_t ores = (int64_t)one - (int64_t)two;
+    return ores == (int64_t)*res;
+}
+
+inline bool
+SafeMul(int32_t one, int32_t two, int32_t *res)
+{
+    *res = uint32_t(one) * uint32_t(two);
+    int64_t ores = (int64_t)one * (int64_t)two;
+    return ores == (int64_t)*res;
+}
+
+extern bool
+ToNumberSlow(ExclusiveContext *cx, Value v, double *dp);
+
+// Variant of ToNumber which takes an ExclusiveContext instead of a JSContext.
+// ToNumber is part of the API and can't use ExclusiveContext directly.
+MOZ_ALWAYS_INLINE bool
+ToNumber(ExclusiveContext *cx, const Value &v, double *out)
+{
+    if (v.isNumber()) {
+        *out = v.toNumber();
+        return true;
+    }
+    return ToNumberSlow(cx, v, out);
+}
+
+/*
+ * Thread safe variants of number conversion functions.
+ */
+
+bool
+NonObjectToNumberSlow(ThreadSafeContext *cx, Value v, double *out);
+
+inline bool
+NonObjectToNumber(ThreadSafeContext *cx, const Value &v, double *out)
+{
+    if (v.isNumber()) {
+        *out = v.toNumber();
+        return true;
+    }
+    return NonObjectToNumberSlow(cx, v, out);
+}
+
+bool
+NonObjectToInt32Slow(ThreadSafeContext *cx, const Value &v, int32_t *out);
+
+inline bool
+NonObjectToInt32(ThreadSafeContext *cx, const Value &v, int32_t *out)
+{
+    if (v.isInt32()) {
+        *out = v.toInt32();
+        return true;
+    }
+    return NonObjectToInt32Slow(cx, v, out);
+}
+
+bool
+NonObjectToUint32Slow(ThreadSafeContext *cx, const Value &v, uint32_t *out);
+
+MOZ_ALWAYS_INLINE bool
+NonObjectToUint32(ThreadSafeContext *cx, const Value &v, uint32_t *out)
+{
+    if (v.isInt32()) {
+        *out = uint32_t(v.toInt32());
+        return true;
+    }
+    return NonObjectToUint32Slow(cx, v, out);
+}
+
+} /* namespace js */
+
+#endif /* jsnum_h */