Cleanup some fgas locale code.

This Cl cleans up a bit of the locale code in fgas, removing unused
code and cleaning up some of the other code.

Change-Id: Ieb18df552cf5d803c1bbdbfe11a4f5a88c4b3af3
Reviewed-on: https://pdfium-review.googlesource.com/3094
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: Nicolás Peña <npm@chromium.org>

1 files changed, 471 insertions, 0 deletions

diff --git a/xfa/fgas/localization/cfx_decimal.cpp b/xfa/fgas/localization/cfx_decimal.cpp
new file mode 100644
index 0000000000..ba70be8230
--- /dev/null
+++ b/xfa/fgas/localization/cfx_decimal.cpp
@@ -0,0 +1,471 @@
+// Copyright 2017 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include <algorithm>
+#include <utility>
+
+#include "xfa/fgas/localization/fgas_locale.h"
+
+#define FXMATH_DECIMAL_SCALELIMIT 0x1c
+#define FXMATH_DECIMAL_NEGMASK (0x80000000L)
+#define FXMATH_DECIMAL_FORCEBOOL(x) (!!(x))
+#define FXMATH_DECIMAL_MAKEFLAGS(NEG, SCALE) \
+  (((SCALE) << 0x10) | ((NEG) ? FXMATH_DECIMAL_NEGMASK : 0))
+#define FXMATH_DECIMAL_FLAGS2NEG(FLAGS) \
+  FXMATH_DECIMAL_FORCEBOOL((FLAGS)&FXMATH_DECIMAL_NEGMASK)
+#define FXMATH_DECIMAL_FLAGS2SCALE(FLAGS) \
+  ((uint8_t)(((FLAGS) & ~FXMATH_DECIMAL_NEGMASK) >> 0x10))
+#define FXMATH_DECIMAL_RSHIFT32BIT(x) ((x) >> 0x10 >> 0x10)
+#define FXMATH_DECIMAL_LSHIFT32BIT(x) ((x) << 0x10 << 0x10)
+
+namespace {
+
+inline uint8_t decimal_helper_div10(uint64_t& phi,
+                                    uint64_t& pmid,
+                                    uint64_t& plo) {
+  uint8_t retVal;
+  pmid += FXMATH_DECIMAL_LSHIFT32BIT(phi % 0xA);
+  phi /= 0xA;
+  plo += FXMATH_DECIMAL_LSHIFT32BIT(pmid % 0xA);
+  pmid /= 0xA;
+  retVal = plo % 0xA;
+  plo /= 0xA;
+  return retVal;
+}
+
+inline uint8_t decimal_helper_div10_any(uint64_t nums[], uint8_t numcount) {
+  uint8_t retVal = 0;
+  for (int i = numcount - 1; i > 0; i--) {
+    nums[i - 1] += FXMATH_DECIMAL_LSHIFT32BIT(nums[i] % 0xA);
+    nums[i] /= 0xA;
+  }
+  if (numcount) {
+    retVal = nums[0] % 0xA;
+    nums[0] /= 0xA;
+  }
+  return retVal;
+}
+
+inline void decimal_helper_mul10(uint64_t& phi, uint64_t& pmid, uint64_t& plo) {
+  plo *= 0xA;
+  pmid = pmid * 0xA + FXMATH_DECIMAL_RSHIFT32BIT(plo);
+  plo = (uint32_t)plo;
+  phi = phi * 0xA + FXMATH_DECIMAL_RSHIFT32BIT(pmid);
+  pmid = (uint32_t)pmid;
+}
+
+inline void decimal_helper_mul10_any(uint64_t nums[], uint8_t numcount) {
+  nums[0] *= 0xA;
+  for (int i = 1; i < numcount; i++) {
+    nums[i] = nums[i] * 0xA + FXMATH_DECIMAL_RSHIFT32BIT(nums[i - 1]);
+    nums[i - 1] = (uint32_t)nums[i - 1];
+  }
+}
+
+inline void decimal_helper_normalize(uint64_t& phi,
+                                     uint64_t& pmid,
+                                     uint64_t& plo) {
+  phi += FXMATH_DECIMAL_RSHIFT32BIT(pmid);
+  pmid = (uint32_t)pmid;
+  pmid += FXMATH_DECIMAL_RSHIFT32BIT(plo);
+  plo = (uint32_t)plo;
+  phi += FXMATH_DECIMAL_RSHIFT32BIT(pmid);
+  pmid = (uint32_t)pmid;
+}
+
+inline void decimal_helper_normalize_any(uint64_t nums[], uint8_t len) {
+  for (int i = len - 2; i > 0; i--) {
+    nums[i + 1] += FXMATH_DECIMAL_RSHIFT32BIT(nums[i]);
+    nums[i] = (uint32_t)nums[i];
+  }
+  for (int i = 0; i < len - 1; i++) {
+    nums[i + 1] += FXMATH_DECIMAL_RSHIFT32BIT(nums[i]);
+    nums[i] = (uint32_t)nums[i];
+  }
+}
+
+inline int8_t decimal_helper_raw_compare_any(uint64_t a[],
+                                             uint8_t al,
+                                             uint64_t b[],
+                                             uint8_t bl) {
+  int8_t retVal = 0;
+  for (int i = std::max(al - 1, bl - 1); i >= 0; i--) {
+    uint64_t l = (i >= al ? 0 : a[i]), r = (i >= bl ? 0 : b[i]);
+    retVal += (l > r ? 1 : (l < r ? -1 : 0));
+    if (retVal)
+      return retVal;
+  }
+  return retVal;
+}
+
+inline void decimal_helper_dec_any(uint64_t a[], uint8_t al) {
+  for (int i = 0; i < al; i++) {
+    if (a[i]--)
+      return;
+  }
+}
+
+inline void decimal_helper_inc_any(uint64_t a[], uint8_t al) {
+  for (int i = 0; i < al; i++) {
+    a[i]++;
+    if ((uint32_t)a[i] == a[i])
+      return;
+    a[i] = 0;
+  }
+}
+
+inline void decimal_helper_raw_mul(uint64_t a[],
+                                   uint8_t al,
+                                   uint64_t b[],
+                                   uint8_t bl,
+                                   uint64_t c[],
+                                   uint8_t cl) {
+  ASSERT(al + bl <= cl);
+  for (int i = 0; i < cl; i++)
+    c[i] = 0;
+
+  for (int i = 0; i < al; i++) {
+    for (int j = 0; j < bl; j++) {
+      uint64_t m = (uint64_t)a[i] * b[j];
+      c[i + j] += (uint32_t)m;
+      c[i + j + 1] += FXMATH_DECIMAL_RSHIFT32BIT(m);
+    }
+  }
+  for (int i = 0; i < cl - 1; i++) {
+    c[i + 1] += FXMATH_DECIMAL_RSHIFT32BIT(c[i]);
+    c[i] = (uint32_t)c[i];
+  }
+  for (int i = 0; i < cl; i++)
+    c[i] = (uint32_t)c[i];
+}
+
+inline void decimal_helper_raw_div(uint64_t a[],
+                                   uint8_t al,
+                                   uint64_t b[],
+                                   uint8_t bl,
+                                   uint64_t c[],
+                                   uint8_t cl) {
+  for (int i = 0; i < cl; i++)
+    c[i] = 0;
+
+  uint64_t left[16] = {0};
+  uint64_t right[16] = {0};
+  left[0] = 0;
+  for (int i = 0; i < al; i++)
+    right[i] = a[i];
+
+  uint64_t tmp[16];
+  while (decimal_helper_raw_compare_any(left, al, right, al) <= 0) {
+    uint64_t cur[16];
+    for (int i = 0; i < al; i++)
+      cur[i] = left[i] + right[i];
+
+    for (int i = al - 1; i >= 0; i--) {
+      if (i)
+        cur[i - 1] += FXMATH_DECIMAL_LSHIFT32BIT(cur[i] % 2);
+      cur[i] /= 2;
+    }
+
+    decimal_helper_raw_mul(cur, al, b, bl, tmp, 16);
+    switch (decimal_helper_raw_compare_any(tmp, 16, a, al)) {
+      case -1:
+        for (int i = 0; i < 16; i++)
+          left[i] = cur[i];
+
+        left[0]++;
+        decimal_helper_normalize_any(left, al);
+        break;
+      case 1:
+        for (int i = 0; i < 16; i++)
+          right[i] = cur[i];
+        decimal_helper_dec_any(right, al);
+        break;
+      case 0:
+        for (int i = 0; i < std::min(al, cl); i++)
+          c[i] = cur[i];
+        return;
+    }
+  }
+  for (int i = 0; i < std::min(al, cl); i++)
+    c[i] = left[i];
+}
+
+inline bool decimal_helper_outofrange(uint64_t a[], uint8_t al, uint8_t goal) {
+  for (int i = goal; i < al; i++) {
+    if (a[i])
+      return true;
+  }
+  return false;
+}
+
+inline void decimal_helper_shrinkintorange(uint64_t a[],
+                                           uint8_t al,
+                                           uint8_t goal,
+                                           uint8_t& scale) {
+  bool bRoundUp = false;
+  while (scale != 0 && (scale > FXMATH_DECIMAL_SCALELIMIT ||
+                        decimal_helper_outofrange(a, al, goal))) {
+    bRoundUp = decimal_helper_div10_any(a, al) >= 5;
+    scale--;
+  }
+  if (bRoundUp) {
+    decimal_helper_normalize_any(a, goal);
+    decimal_helper_inc_any(a, goal);
+  }
+}
+
+inline void decimal_helper_truncate(uint64_t& phi,
+                                    uint64_t& pmid,
+                                    uint64_t& plo,
+                                    uint8_t& scale,
+                                    uint8_t minscale = 0) {
+  while (scale > minscale) {
+    uint64_t thi = phi, tmid = pmid, tlo = plo;
+    if (decimal_helper_div10(thi, tmid, tlo) != 0)
+      break;
+
+    phi = thi;
+    pmid = tmid;
+    plo = tlo;
+    scale--;
+  }
+}
+
+}  // namespace
+
+CFX_Decimal::CFX_Decimal() : m_uHi(0), m_uLo(0), m_uMid(0), m_uFlags(0) {}
+
+CFX_Decimal::CFX_Decimal(uint64_t val)
+    : m_uHi(0),
+      m_uLo(static_cast<uint32_t>(val)),
+      m_uMid(static_cast<uint32_t>(FXMATH_DECIMAL_RSHIFT32BIT(val))),
+      m_uFlags(0) {}
+
+CFX_Decimal::CFX_Decimal(uint32_t val)
+    : m_uHi(0), m_uLo(static_cast<uint32_t>(val)), m_uMid(0), m_uFlags(0) {}
+
+CFX_Decimal::CFX_Decimal(uint32_t lo,
+                         uint32_t mid,
+                         uint32_t hi,
+                         bool neg,
+                         uint8_t scale)
+    : m_uHi(hi),
+      m_uLo(lo),
+      m_uMid(mid),
+      m_uFlags(FXMATH_DECIMAL_MAKEFLAGS(
+          neg && IsNotZero(),
+          (scale > FXMATH_DECIMAL_SCALELIMIT ? 0 : scale))) {}
+
+CFX_Decimal::CFX_Decimal(int32_t val) {
+  if (val >= 0) {
+    *this = CFX_Decimal(static_cast<uint32_t>(val));
+  } else {
+    *this = CFX_Decimal(static_cast<uint32_t>(-val));
+    SetNegate();
+  }
+}
+
+CFX_Decimal::CFX_Decimal(float val, uint8_t scale) {
+  float newval = fabs(val);
+  uint64_t phi;
+  uint64_t pmid;
+  uint64_t plo;
+  plo = static_cast<uint64_t>(newval);
+  pmid = static_cast<uint64_t>(newval / 1e32);
+  phi = static_cast<uint64_t>(newval / 1e64);
+  newval = FXSYS_fmod(newval, 1.0f);
+  for (uint8_t iter = 0; iter < scale; iter++) {
+    decimal_helper_mul10(phi, pmid, plo);
+    newval *= 10;
+    plo += static_cast<uint64_t>(newval);
+    newval = FXSYS_fmod(newval, 1.0f);
+  }
+
+  plo += FXSYS_round(newval);
+  decimal_helper_normalize(phi, pmid, plo);
+  m_uHi = static_cast<uint32_t>(phi);
+  m_uMid = static_cast<uint32_t>(pmid);
+  m_uLo = static_cast<uint32_t>(plo);
+  m_uFlags = FXMATH_DECIMAL_MAKEFLAGS(val < 0 && IsNotZero(), scale);
+}
+
+CFX_Decimal::CFX_Decimal(const CFX_WideStringC& strObj) {
+  const wchar_t* str = strObj.c_str();
+  const wchar_t* strBound = str + strObj.GetLength();
+  bool pointmet = false;
+  bool negmet = false;
+  uint8_t scale = 0;
+  m_uHi = 0;
+  m_uMid = 0;
+  m_uLo = 0;
+  while (str != strBound && *str == ' ')
+    str++;
+  if (str != strBound && *str == '-') {
+    negmet = 1;
+    str++;
+  } else if (str != strBound && *str == '+') {
+    str++;
+  }
+
+  while (str != strBound && ((*str >= '0' && *str <= '9') || *str == '.') &&
+         scale < FXMATH_DECIMAL_SCALELIMIT) {
+    if (*str == '.') {
+      if (!pointmet)
+        pointmet = 1;
+    } else {
+      m_uHi = m_uHi * 0xA + FXMATH_DECIMAL_RSHIFT32BIT((uint64_t)m_uMid * 0xA);
+      m_uMid = m_uMid * 0xA + FXMATH_DECIMAL_RSHIFT32BIT((uint64_t)m_uLo * 0xA);
+      m_uLo = m_uLo * 0xA + (*str - '0');
+      if (pointmet)
+        scale++;
+    }
+    str++;
+  }
+  m_uFlags = FXMATH_DECIMAL_MAKEFLAGS(negmet && IsNotZero(), scale);
+}
+
+CFX_Decimal::operator CFX_WideString() const {
+  CFX_WideString retString;
+  CFX_WideString tmpbuf;
+  uint64_t phi = m_uHi;
+  uint64_t pmid = m_uMid;
+  uint64_t plo = m_uLo;
+  while (phi || pmid || plo)
+    tmpbuf += decimal_helper_div10(phi, pmid, plo) + '0';
+
+  uint8_t outputlen = (uint8_t)tmpbuf.GetLength();
+  uint8_t scale = (uint8_t)FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags);
+  while (scale >= outputlen) {
+    tmpbuf += '0';
+    outputlen++;
+  }
+  if (FXMATH_DECIMAL_FLAGS2NEG(m_uFlags) && IsNotZero())
+    retString += '-';
+
+  for (uint8_t idx = 0; idx < outputlen; idx++) {
+    if (idx == (outputlen - scale) && scale != 0)
+      retString += '.';
+    retString += tmpbuf[outputlen - 1 - idx];
+  }
+  return retString;
+}
+
+CFX_Decimal::operator double() const {
+  double pow = (double)(1 << 16) * (1 << 16);
+  double base = static_cast<double>(m_uHi) * pow * pow +
+                static_cast<double>(m_uMid) * pow + static_cast<double>(m_uLo);
+  int8_t scale = FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags);
+  bool bNeg = FXMATH_DECIMAL_FLAGS2NEG(m_uFlags);
+  return (bNeg ? -1 : 1) * base * ::pow(10.0, -scale);
+}
+
+void CFX_Decimal::SetScale(uint8_t newscale) {
+  uint8_t oldscale = FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags);
+  if (newscale > oldscale) {
+    uint64_t phi = m_uHi;
+    uint64_t pmid = m_uMid;
+    uint64_t plo = m_uLo;
+    for (uint8_t iter = 0; iter < newscale - oldscale; iter++)
+      decimal_helper_mul10(phi, pmid, plo);
+
+    m_uHi = static_cast<uint32_t>(phi);
+    m_uMid = static_cast<uint32_t>(pmid);
+    m_uLo = static_cast<uint32_t>(plo);
+    m_uFlags = FXMATH_DECIMAL_MAKEFLAGS(
+        FXMATH_DECIMAL_FLAGS2NEG(m_uFlags) && IsNotZero(), newscale);
+  } else if (newscale < oldscale) {
+    uint64_t phi;
+    uint64_t pmid;
+    uint64_t plo;
+    phi = 0;
+    pmid = 0;
+    plo = 5;
+    for (uint8_t iter = 0; iter < oldscale - newscale - 1; iter++)
+      decimal_helper_mul10(phi, pmid, plo);
+
+    phi += m_uHi;
+    pmid += m_uMid;
+    plo += m_uLo;
+    decimal_helper_normalize(phi, pmid, plo);
+    for (uint8_t iter = 0; iter < oldscale - newscale; iter++)
+      decimal_helper_div10(phi, pmid, plo);
+
+    m_uHi = static_cast<uint32_t>(phi);
+    m_uMid = static_cast<uint32_t>(pmid);
+    m_uLo = static_cast<uint32_t>(plo);
+    m_uFlags = FXMATH_DECIMAL_MAKEFLAGS(
+        FXMATH_DECIMAL_FLAGS2NEG(m_uFlags) && IsNotZero(), newscale);
+  }
+}
+
+uint8_t CFX_Decimal::GetScale() {
+  return FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags);
+}
+
+void CFX_Decimal::SetNegate() {
+  if (IsNotZero())
+    m_uFlags ^= FXMATH_DECIMAL_NEGMASK;
+}
+
+void CFX_Decimal::Swap(CFX_Decimal& val) {
+  std::swap(m_uHi, val.m_uHi);
+  std::swap(m_uMid, val.m_uMid);
+  std::swap(m_uLo, val.m_uLo);
+  std::swap(m_uFlags, val.m_uFlags);
+}
+
+CFX_Decimal CFX_Decimal::operator*(const CFX_Decimal& val) const {
+  uint64_t a[3] = {m_uLo, m_uMid, m_uHi},
+           b[3] = {val.m_uLo, val.m_uMid, val.m_uHi};
+  uint64_t c[6];
+  decimal_helper_raw_mul(a, 3, b, 3, c, 6);
+  bool neg = FXMATH_DECIMAL_FLAGS2NEG(m_uFlags) ^
+             FXMATH_DECIMAL_FLAGS2NEG(val.m_uFlags);
+  uint8_t scale = FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags) +
+                  FXMATH_DECIMAL_FLAGS2SCALE(val.m_uFlags);
+  decimal_helper_shrinkintorange(c, 6, 3, scale);
+  return CFX_Decimal(static_cast<uint32_t>(c[0]), static_cast<uint32_t>(c[1]),
+                     static_cast<uint32_t>(c[2]), neg, scale);
+}
+
+CFX_Decimal CFX_Decimal::operator/(const CFX_Decimal& val) const {
+  if (!val.IsNotZero())
+    return CFX_Decimal();
+
+  bool neg = FXMATH_DECIMAL_FLAGS2NEG(m_uFlags) ^
+             FXMATH_DECIMAL_FLAGS2NEG(val.m_uFlags);
+  uint64_t a[7] = {m_uLo, m_uMid, m_uHi},
+           b[3] = {val.m_uLo, val.m_uMid, val.m_uHi}, c[7] = {0};
+  uint8_t scale = 0;
+  if (FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags) <
+      FXMATH_DECIMAL_FLAGS2SCALE(val.m_uFlags)) {
+    for (int i = FXMATH_DECIMAL_FLAGS2SCALE(val.m_uFlags) -
+                 FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags);
+         i > 0; i--) {
+      decimal_helper_mul10_any(a, 7);
+    }
+  } else {
+    scale = FXMATH_DECIMAL_FLAGS2SCALE(m_uFlags) -
+            FXMATH_DECIMAL_FLAGS2SCALE(val.m_uFlags);
+  }
+
+  uint8_t minscale = scale;
+  if (!IsNotZero())
+    return CFX_Decimal(0, 0, 0, 0, minscale);
+
+  while (!a[6]) {
+    decimal_helper_mul10_any(a, 7);
+    scale++;
+  }
+
+  decimal_helper_div10_any(a, 7);
+  scale--;
+  decimal_helper_raw_div(a, 6, b, 3, c, 7);
+  decimal_helper_shrinkintorange(c, 6, 3, scale);
+  decimal_helper_truncate(c[2], c[1], c[0], scale, minscale);
+  return CFX_Decimal(static_cast<uint32_t>(c[0]), static_cast<uint32_t>(c[1]),
+                     static_cast<uint32_t>(c[2]), neg, scale);
+}