Add m-esr52 at 52.6.0

1 files changed, 527 insertions, 0 deletions

diff --git a/js/src/jsdtoa.cpp b/js/src/jsdtoa.cpp
new file mode 100644
index 0000000000..69f50b1df0
--- /dev/null
+++ b/js/src/jsdtoa.cpp
@@ -0,0 +1,527 @@
+/* -*- 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/. */
+
+/*
+ * Portable double to alphanumeric string and back converters.
+ */
+
+#include "jsdtoa.h"
+
+#include "jsprf.h"
+#include "jstypes.h"
+#include "jsutil.h"
+
+using namespace js;
+
+#if MOZ_LITTLE_ENDIAN
+#define IEEE_8087
+#else
+#define IEEE_MC68k
+#endif
+
+#ifndef Long
+#define Long int32_t
+#endif
+
+#ifndef ULong
+#define ULong uint32_t
+#endif
+
+/*
+#ifndef Llong
+#define Llong int64_t
+#endif
+
+#ifndef ULlong
+#define ULlong uint64_t
+#endif
+*/
+
+// dtoa.c requires that MALLOC be infallible. Furthermore, its allocations are
+// few and small. So AutoEnterOOMUnsafeRegion is appropriate here.
+static inline void* dtoa_malloc(size_t size)
+{
+    AutoEnterOOMUnsafeRegion oomUnsafe;
+    void* p = js_malloc(size);
+    if (!p)
+        oomUnsafe.crash("dtoa_malloc");
+
+    return p;
+}
+
+static inline void dtoa_free(void* p)
+{
+  return js_free(p);
+}
+
+#define NO_GLOBAL_STATE
+#define NO_ERRNO
+#define Omit_Private_Memory // This saves memory for the workloads we see.
+#define MALLOC dtoa_malloc
+#define FREE dtoa_free
+#include "dtoa.c"
+
+/* Mapping of JSDToStrMode -> js_dtoa mode */
+static const uint8_t dtoaModes[] = {
+    0,   /* DTOSTR_STANDARD */
+    0,   /* DTOSTR_STANDARD_EXPONENTIAL, */
+    3,   /* DTOSTR_FIXED, */
+    2,   /* DTOSTR_EXPONENTIAL, */
+    2};  /* DTOSTR_PRECISION */
+
+double
+js_strtod_harder(DtoaState* state, const char* s00, char** se, int* err)
+{
+    double retval;
+    if (err)
+        *err = 0;
+    retval = _strtod(state, s00, se);
+    return retval;
+}
+
+char*
+js_dtostr(DtoaState* state, char* buffer, size_t bufferSize, JSDToStrMode mode, int precision,
+          double dinput)
+{
+    U d;
+    int decPt;        /* Offset of decimal point from first digit */
+    int sign;         /* Nonzero if the sign bit was set in d */
+    int nDigits;      /* Number of significand digits returned by js_dtoa */
+    char* numBegin;   /* Pointer to the digits returned by js_dtoa */
+    char* numEnd = 0; /* Pointer past the digits returned by js_dtoa */
+
+    MOZ_ASSERT(bufferSize >= (size_t)(mode <= DTOSTR_STANDARD_EXPONENTIAL
+                                     ? DTOSTR_STANDARD_BUFFER_SIZE
+                                     : DTOSTR_VARIABLE_BUFFER_SIZE(precision)));
+
+    /*
+     * Change mode here rather than below because the buffer may not be large
+     * enough to hold a large integer.
+     */
+    if (mode == DTOSTR_FIXED && (dinput >= 1e21 || dinput <= -1e21))
+        mode = DTOSTR_STANDARD;
+
+    dval(d) = dinput;
+    numBegin = dtoa(PASS_STATE d, dtoaModes[mode], precision, &decPt, &sign, &numEnd);
+    if (!numBegin) {
+        return nullptr;
+    }
+
+    nDigits = numEnd - numBegin;
+    MOZ_ASSERT((size_t) nDigits <= bufferSize - 2);
+    if ((size_t) nDigits > bufferSize - 2) {
+        return nullptr;
+    }
+
+    js_memcpy(buffer + 2, numBegin, nDigits);
+    freedtoa(PASS_STATE numBegin);
+    numBegin = buffer + 2; /* +2 leaves space for sign and/or decimal point */
+    numEnd = numBegin + nDigits;
+    *numEnd = '\0';
+
+    /* If Infinity, -Infinity, or NaN, return the string regardless of mode. */
+    if (decPt != 9999) {
+        bool exponentialNotation = false;
+        int minNDigits = 0;  /* Min number of significant digits required */
+        char* p;
+        char* q;
+
+        switch (mode) {
+            case DTOSTR_STANDARD:
+                if (decPt < -5 || decPt > 21)
+                    exponentialNotation = true;
+                else
+                    minNDigits = decPt;
+                break;
+
+            case DTOSTR_FIXED:
+                if (precision >= 0)
+                    minNDigits = decPt + precision;
+                else
+                    minNDigits = decPt;
+                break;
+
+            case DTOSTR_EXPONENTIAL:
+                MOZ_ASSERT(precision > 0);
+                minNDigits = precision;
+                MOZ_FALLTHROUGH;
+            case DTOSTR_STANDARD_EXPONENTIAL:
+                exponentialNotation = true;
+                break;
+
+            case DTOSTR_PRECISION:
+                MOZ_ASSERT(precision > 0);
+                minNDigits = precision;
+                if (decPt < -5 || decPt > precision)
+                    exponentialNotation = true;
+                break;
+        }
+
+        /* If the number has fewer than minNDigits, end-pad it with zeros. */
+        if (nDigits < minNDigits) {
+            p = numBegin + minNDigits;
+            nDigits = minNDigits;
+            do {
+                *numEnd++ = '0';
+            } while (numEnd != p);
+            *numEnd = '\0';
+        }
+
+        if (exponentialNotation) {
+            /* Insert a decimal point if more than one significand digit */
+            if (nDigits != 1) {
+                numBegin--;
+                numBegin[0] = numBegin[1];
+                numBegin[1] = '.';
+            }
+            snprintf(numEnd, bufferSize - (numEnd - buffer), "e%+d", decPt-1);
+        } else if (decPt != nDigits) {
+            /* Some kind of a fraction in fixed notation */
+            MOZ_ASSERT(decPt <= nDigits);
+            if (decPt > 0) {
+                /* dd...dd . dd...dd */
+                p = --numBegin;
+                do {
+                    *p = p[1];
+                    p++;
+                } while (--decPt);
+                *p = '.';
+            } else {
+                /* 0 . 00...00dd...dd */
+                p = numEnd;
+                numEnd += 1 - decPt;
+                q = numEnd;
+                MOZ_ASSERT(numEnd < buffer + bufferSize);
+                *numEnd = '\0';
+                while (p != numBegin)
+                    *--q = *--p;
+                for (p = numBegin + 1; p != q; p++)
+                    *p = '0';
+                *numBegin = '.';
+                *--numBegin = '0';
+            }
+        }
+    }
+
+    /* If negative and neither -0.0 nor NaN, output a leading '-'. */
+    if (sign &&
+            !(word0(d) == Sign_bit && word1(d) == 0) &&
+            !((word0(d) & Exp_mask) == Exp_mask &&
+              (word1(d) || (word0(d) & Frac_mask)))) {
+        *--numBegin = '-';
+    }
+    return numBegin;
+}
+
+
+/* Let b = floor(b / divisor), and return the remainder.  b must be nonnegative.
+ * divisor must be between 1 and 65536.
+ * This function cannot run out of memory. */
+static uint32_t
+divrem(Bigint* b, uint32_t divisor)
+{
+    int32_t n = b->wds;
+    uint32_t remainder = 0;
+    ULong* bx;
+    ULong* bp;
+
+    MOZ_ASSERT(divisor > 0 && divisor <= 65536);
+
+    if (!n)
+        return 0; /* b is zero */
+    bx = b->x;
+    bp = bx + n;
+    do {
+        ULong a = *--bp;
+        ULong dividend = remainder << 16 | a >> 16;
+        ULong quotientHi = dividend / divisor;
+        ULong quotientLo;
+
+        remainder = dividend - quotientHi*divisor;
+        MOZ_ASSERT(quotientHi <= 0xFFFF && remainder < divisor);
+        dividend = remainder << 16 | (a & 0xFFFF);
+        quotientLo = dividend / divisor;
+        remainder = dividend - quotientLo*divisor;
+        MOZ_ASSERT(quotientLo <= 0xFFFF && remainder < divisor);
+        *bp = quotientHi << 16 | quotientLo;
+    } while (bp != bx);
+    /* Decrease the size of the number if its most significant word is now zero. */
+    if (bx[n-1] == 0)
+        b->wds--;
+    return remainder;
+}
+
+/* Return floor(b/2^k) and set b to be the remainder.  The returned quotient must be less than 2^32. */
+static uint32_t quorem2(Bigint* b, int32_t k)
+{
+    ULong mask;
+    ULong result;
+    ULong* bx;
+    ULong* bxe;
+    int32_t w;
+    int32_t n = k >> 5;
+    k &= 0x1F;
+    mask = (1<<k) - 1;
+
+    w = b->wds - n;
+    if (w <= 0)
+        return 0;
+    MOZ_ASSERT(w <= 2);
+    bx = b->x;
+    bxe = bx + n;
+    result = *bxe >> k;
+    *bxe &= mask;
+    if (w == 2) {
+        MOZ_ASSERT(!(bxe[1] & ~mask));
+        if (k)
+            result |= bxe[1] << (32 - k);
+    }
+    n++;
+    while (!*bxe && bxe != bx) {
+        n--;
+        bxe--;
+    }
+    b->wds = n;
+    return result;
+}
+
+
+/* "-0.0000...(1073 zeros after decimal point)...0001\0" is the longest string that we could produce,
+ * which occurs when printing -5e-324 in binary.  We could compute a better estimate of the size of
+ * the output string and malloc fewer bytes depending on d and base, but why bother? */
+#define DTOBASESTR_BUFFER_SIZE 1078
+#define BASEDIGIT(digit) ((char)(((digit) >= 10) ? 'a' - 10 + (digit) : '0' + (digit)))
+
+char*
+js_dtobasestr(DtoaState* state, int base, double dinput)
+{
+    U d;
+    char* buffer;        /* The output string */
+    char* p;             /* Pointer to current position in the buffer */
+    char* pInt;          /* Pointer to the beginning of the integer part of the string */
+    char* q;
+    uint32_t digit;
+    U di;                /* d truncated to an integer */
+    U df;                /* The fractional part of d */
+
+    MOZ_ASSERT(base >= 2 && base <= 36);
+
+    dval(d) = dinput;
+    buffer = (char*) js_malloc(DTOBASESTR_BUFFER_SIZE);
+    if (!buffer)
+        return nullptr;
+    p = buffer;
+
+    if (dval(d) < 0.0
+#if defined(XP_WIN)
+        && !((word0(d) & Exp_mask) == Exp_mask && ((word0(d) & Frac_mask) || word1(d))) /* Visual C++ doesn't know how to compare against NaN */
+#endif
+       ) {
+        *p++ = '-';
+        dval(d) = -dval(d);
+    }
+
+    /* Check for Infinity and NaN */
+    if ((word0(d) & Exp_mask) == Exp_mask) {
+        strcpy(p, !word1(d) && !(word0(d) & Frac_mask) ? "Infinity" : "NaN");
+        return buffer;
+    }
+
+    /* Output the integer part of d with the digits in reverse order. */
+    pInt = p;
+    dval(di) = floor(dval(d));
+    if (dval(di) <= 4294967295.0) {
+        uint32_t n = (uint32_t)dval(di);
+        if (n)
+            do {
+                uint32_t m = n / base;
+                digit = n - m*base;
+                n = m;
+                MOZ_ASSERT(digit < (uint32_t)base);
+                *p++ = BASEDIGIT(digit);
+            } while (n);
+        else *p++ = '0';
+    } else {
+        int e;
+        int bits;  /* Number of significant bits in di; not used. */
+        Bigint* b = d2b(PASS_STATE di, &e, &bits);
+        if (!b)
+            goto nomem1;
+        b = lshift(PASS_STATE b, e);
+        if (!b) {
+          nomem1:
+            Bfree(PASS_STATE b);
+            js_free(buffer);
+            return nullptr;
+        }
+        do {
+            digit = divrem(b, base);
+            MOZ_ASSERT(digit < (uint32_t)base);
+            *p++ = BASEDIGIT(digit);
+        } while (b->wds);
+        Bfree(PASS_STATE b);
+    }
+    /* Reverse the digits of the integer part of d. */
+    q = p-1;
+    while (q > pInt) {
+        char ch = *pInt;
+        *pInt++ = *q;
+        *q-- = ch;
+    }
+
+    dval(df) = dval(d) - dval(di);
+    if (dval(df) != 0.0) {
+        /* We have a fraction. */
+        int e, bbits;
+        int32_t s2, done;
+        Bigint* b = nullptr;
+        Bigint* s = nullptr;
+        Bigint* mlo = nullptr;
+        Bigint* mhi = nullptr;
+
+        *p++ = '.';
+        b = d2b(PASS_STATE df, &e, &bbits);
+        if (!b) {
+          nomem2:
+            Bfree(PASS_STATE b);
+            Bfree(PASS_STATE s);
+            if (mlo != mhi)
+                Bfree(PASS_STATE mlo);
+            Bfree(PASS_STATE mhi);
+            js_free(buffer);
+            return nullptr;
+        }
+        MOZ_ASSERT(e < 0);
+        /* At this point df = b * 2^e.  e must be less than zero because 0 < df < 1. */
+
+        s2 = -(int32_t)(word0(d) >> Exp_shift1 & Exp_mask>>Exp_shift1);
+#ifndef Sudden_Underflow
+        if (!s2)
+            s2 = -1;
+#endif
+        s2 += Bias + P;
+        /* 1/2^s2 = (nextDouble(d) - d)/2 */
+        MOZ_ASSERT(-s2 < e);
+        mlo = i2b(PASS_STATE 1);
+        if (!mlo)
+            goto nomem2;
+        mhi = mlo;
+        if (!word1(d) && !(word0(d) & Bndry_mask)
+#ifndef Sudden_Underflow
+            && word0(d) & (Exp_mask & Exp_mask << 1)
+#endif
+            ) {
+            /* The special case.  Here we want to be within a quarter of the last input
+               significant digit instead of one half of it when the output string's value is less than d.  */
+            s2 += Log2P;
+            mhi = i2b(PASS_STATE 1<<Log2P);
+            if (!mhi)
+                goto nomem2;
+        }
+        b = lshift(PASS_STATE b, e + s2);
+        if (!b)
+            goto nomem2;
+        s = i2b(PASS_STATE 1);
+        if (!s)
+            goto nomem2;
+        s = lshift(PASS_STATE s, s2);
+        if (!s)
+            goto nomem2;
+        /* At this point we have the following:
+         *   s = 2^s2;
+         *   1 > df = b/2^s2 > 0;
+         *   (d - prevDouble(d))/2 = mlo/2^s2;
+         *   (nextDouble(d) - d)/2 = mhi/2^s2. */
+
+        done = false;
+        do {
+            int32_t j, j1;
+            Bigint* delta;
+
+            b = multadd(PASS_STATE b, base, 0);
+            if (!b)
+                goto nomem2;
+            digit = quorem2(b, s2);
+            if (mlo == mhi) {
+                mlo = mhi = multadd(PASS_STATE mlo, base, 0);
+                if (!mhi)
+                    goto nomem2;
+            }
+            else {
+                mlo = multadd(PASS_STATE mlo, base, 0);
+                if (!mlo)
+                    goto nomem2;
+                mhi = multadd(PASS_STATE mhi, base, 0);
+                if (!mhi)
+                    goto nomem2;
+            }
+
+            /* Do we yet have the shortest string that will round to d? */
+            j = cmp(b, mlo);
+            /* j is b/2^s2 compared with mlo/2^s2. */
+            delta = diff(PASS_STATE s, mhi);
+            if (!delta)
+                goto nomem2;
+            j1 = delta->sign ? 1 : cmp(b, delta);
+            Bfree(PASS_STATE delta);
+            /* j1 is b/2^s2 compared with 1 - mhi/2^s2. */
+
+#ifndef ROUND_BIASED
+            if (j1 == 0 && !(word1(d) & 1)) {
+                if (j > 0)
+                    digit++;
+                done = true;
+            } else
+#endif
+            if (j < 0 || (j == 0
+#ifndef ROUND_BIASED
+                && !(word1(d) & 1)
+#endif
+                )) {
+                if (j1 > 0) {
+                    /* Either dig or dig+1 would work here as the least significant digit.
+                       Use whichever would produce an output value closer to d. */
+                    b = lshift(PASS_STATE b, 1);
+                    if (!b)
+                        goto nomem2;
+                    j1 = cmp(b, s);
+                    if (j1 > 0) /* The even test (|| (j1 == 0 && (digit & 1))) is not here because it messes up odd base output
+                                 * such as 3.5 in base 3.  */
+                        digit++;
+                }
+                done = true;
+            } else if (j1 > 0) {
+                digit++;
+                done = true;
+            }
+            MOZ_ASSERT(digit < (uint32_t)base);
+            *p++ = BASEDIGIT(digit);
+        } while (!done);
+        Bfree(PASS_STATE b);
+        Bfree(PASS_STATE s);
+        if (mlo != mhi)
+            Bfree(PASS_STATE mlo);
+        Bfree(PASS_STATE mhi);
+    }
+    MOZ_ASSERT(p < buffer + DTOBASESTR_BUFFER_SIZE);
+    *p = '\0';
+    return buffer;
+}
+
+DtoaState*
+js::NewDtoaState()
+{
+    return newdtoa();
+}
+
+void
+js::DestroyDtoaState(DtoaState* state)
+{
+    destroydtoa(state);
+}
+
+/* Cleanup pollution from dtoa.c */
+#undef Bias