Move V8 to external/v8
Change-Id: If68025d67453785a651c5dfb34fad298c16676a4
diff --git a/src/utils.h b/src/utils.h
new file mode 100644
index 0000000..275dbb5
--- /dev/null
+++ b/src/utils.h
@@ -0,0 +1,581 @@
+// Copyright 2006-2008 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following
+// disclaimer in the documentation and/or other materials provided
+// with the distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef V8_UTILS_H_
+#define V8_UTILS_H_
+
+#include <stdlib.h>
+
+namespace v8 {
+namespace internal {
+
+// ----------------------------------------------------------------------------
+// General helper functions
+
+// Returns true iff x is a power of 2. Does not work for zero.
+template <typename T>
+static inline bool IsPowerOf2(T x) {
+ return (x & (x - 1)) == 0;
+}
+
+
+// The C++ standard leaves the semantics of '>>' undefined for
+// negative signed operands. Most implementations do the right thing,
+// though.
+static inline int ArithmeticShiftRight(int x, int s) {
+ return x >> s;
+}
+
+
+// Compute the 0-relative offset of some absolute value x of type T.
+// This allows conversion of Addresses and integral types into
+// 0-relative int offsets.
+template <typename T>
+static inline intptr_t OffsetFrom(T x) {
+ return x - static_cast<T>(0);
+}
+
+
+// Compute the absolute value of type T for some 0-relative offset x.
+// This allows conversion of 0-relative int offsets into Addresses and
+// integral types.
+template <typename T>
+static inline T AddressFrom(intptr_t x) {
+ return static_cast<T>(0) + x;
+}
+
+
+// Return the largest multiple of m which is <= x.
+template <typename T>
+static inline T RoundDown(T x, int m) {
+ ASSERT(IsPowerOf2(m));
+ return AddressFrom<T>(OffsetFrom(x) & -m);
+}
+
+
+// Return the smallest multiple of m which is >= x.
+template <typename T>
+static inline T RoundUp(T x, int m) {
+ return RoundDown(x + m - 1, m);
+}
+
+
+template <typename T>
+static int Compare(const T& a, const T& b) {
+ if (a == b)
+ return 0;
+ else if (a < b)
+ return -1;
+ else
+ return 1;
+}
+
+
+template <typename T>
+static int PointerValueCompare(const T* a, const T* b) {
+ return Compare<T>(*a, *b);
+}
+
+
+// Returns the smallest power of two which is >= x. If you pass in a
+// number that is already a power of two, it is returned as is.
+uint32_t RoundUpToPowerOf2(uint32_t x);
+
+
+template <typename T>
+static inline bool IsAligned(T value, T alignment) {
+ ASSERT(IsPowerOf2(alignment));
+ return (value & (alignment - 1)) == 0;
+}
+
+
+// Returns true if (addr + offset) is aligned.
+static inline bool IsAddressAligned(Address addr,
+ intptr_t alignment,
+ int offset) {
+ intptr_t offs = OffsetFrom(addr + offset);
+ return IsAligned(offs, alignment);
+}
+
+
+// Returns the maximum of the two parameters.
+template <typename T>
+static T Max(T a, T b) {
+ return a < b ? b : a;
+}
+
+
+// Returns the minimum of the two parameters.
+template <typename T>
+static T Min(T a, T b) {
+ return a < b ? a : b;
+}
+
+
+// ----------------------------------------------------------------------------
+// BitField is a help template for encoding and decode bitfield with
+// unsigned content.
+template<class T, int shift, int size>
+class BitField {
+ public:
+ // Tells whether the provided value fits into the bit field.
+ static bool is_valid(T value) {
+ return (static_cast<uint32_t>(value) & ~((1U << (size)) - 1)) == 0;
+ }
+
+ // Returns a uint32_t mask of bit field.
+ static uint32_t mask() {
+ return (1U << (size + shift)) - (1U << shift);
+ }
+
+ // Returns a uint32_t with the bit field value encoded.
+ static uint32_t encode(T value) {
+ ASSERT(is_valid(value));
+ return static_cast<uint32_t>(value) << shift;
+ }
+
+ // Extracts the bit field from the value.
+ static T decode(uint32_t value) {
+ return static_cast<T>((value >> shift) & ((1U << (size)) - 1));
+ }
+};
+
+
+// ----------------------------------------------------------------------------
+// Support for compressed, machine-independent encoding
+// and decoding of integer values of arbitrary size.
+
+// Encoding and decoding from/to a buffer at position p;
+// the result is the position after the encoded integer.
+// Small signed integers in the range -64 <= x && x < 64
+// are encoded in 1 byte; larger values are encoded in 2
+// or more bytes. At most sizeof(int) + 1 bytes are used
+// in the worst case.
+byte* EncodeInt(byte* p, int x);
+byte* DecodeInt(byte* p, int* x);
+
+
+// Encoding and decoding from/to a buffer at position p - 1
+// moving backward; the result is the position of the last
+// byte written. These routines are useful to read/write
+// into a buffer starting at the end of the buffer.
+byte* EncodeUnsignedIntBackward(byte* p, unsigned int x);
+
+// The decoding function is inlined since its performance is
+// important to mark-sweep garbage collection.
+inline byte* DecodeUnsignedIntBackward(byte* p, unsigned int* x) {
+ byte b = *--p;
+ if (b >= 128) {
+ *x = static_cast<unsigned int>(b) - 128;
+ return p;
+ }
+ unsigned int r = static_cast<unsigned int>(b);
+ unsigned int s = 7;
+ b = *--p;
+ while (b < 128) {
+ r |= static_cast<unsigned int>(b) << s;
+ s += 7;
+ b = *--p;
+ }
+ // b >= 128
+ *x = r | ((static_cast<unsigned int>(b) - 128) << s);
+ return p;
+}
+
+
+// ----------------------------------------------------------------------------
+// Hash function.
+
+uint32_t ComputeIntegerHash(uint32_t key);
+
+
+// ----------------------------------------------------------------------------
+// I/O support.
+
+// Our version of printf(). Avoids compilation errors that we get
+// with standard printf when attempting to print pointers, etc.
+// (the errors are due to the extra compilation flags, which we
+// want elsewhere).
+void PrintF(const char* format, ...);
+
+// Our version of fflush.
+void Flush();
+
+
+// Read a line of characters after printing the prompt to stdout. The resulting
+// char* needs to be disposed off with DeleteArray by the caller.
+char* ReadLine(const char* prompt);
+
+
+// Read and return the raw bytes in a file. the size of the buffer is returned
+// in size.
+// The returned buffer must be freed by the caller.
+byte* ReadBytes(const char* filename, int* size, bool verbose = true);
+
+
+// Write size chars from str to the file given by filename.
+// The file is overwritten. Returns the number of chars written.
+int WriteChars(const char* filename,
+ const char* str,
+ int size,
+ bool verbose = true);
+
+
+// Write size bytes to the file given by filename.
+// The file is overwritten. Returns the number of bytes written.
+int WriteBytes(const char* filename,
+ const byte* bytes,
+ int size,
+ bool verbose = true);
+
+
+// Write the C code
+// const char* <varname> = "<str>";
+// const int <varname>_len = <len>;
+// to the file given by filename. Only the first len chars are written.
+int WriteAsCFile(const char* filename, const char* varname,
+ const char* str, int size, bool verbose = true);
+
+
+// ----------------------------------------------------------------------------
+// Miscellaneous
+
+// A static resource holds a static instance that can be reserved in
+// a local scope using an instance of Access. Attempts to re-reserve
+// the instance will cause an error.
+template <typename T>
+class StaticResource {
+ public:
+ StaticResource() : is_reserved_(false) {}
+
+ private:
+ template <typename S> friend class Access;
+ T instance_;
+ bool is_reserved_;
+};
+
+
+// Locally scoped access to a static resource.
+template <typename T>
+class Access {
+ public:
+ explicit Access(StaticResource<T>* resource)
+ : resource_(resource)
+ , instance_(&resource->instance_) {
+ ASSERT(!resource->is_reserved_);
+ resource->is_reserved_ = true;
+ }
+
+ ~Access() {
+ resource_->is_reserved_ = false;
+ resource_ = NULL;
+ instance_ = NULL;
+ }
+
+ T* value() { return instance_; }
+ T* operator -> () { return instance_; }
+
+ private:
+ StaticResource<T>* resource_;
+ T* instance_;
+};
+
+
+template <typename T>
+class Vector {
+ public:
+ Vector() : start_(NULL), length_(0) {}
+ Vector(T* data, int length) : start_(data), length_(length) {
+ ASSERT(length == 0 || (length > 0 && data != NULL));
+ }
+
+ static Vector<T> New(int length) {
+ return Vector<T>(NewArray<T>(length), length);
+ }
+
+ // Returns a vector using the same backing storage as this one,
+ // spanning from and including 'from', to but not including 'to'.
+ Vector<T> SubVector(int from, int to) {
+ ASSERT(from < length_);
+ ASSERT(to <= length_);
+ ASSERT(from < to);
+ return Vector<T>(start() + from, to - from);
+ }
+
+ // Returns the length of the vector.
+ int length() const { return length_; }
+
+ // Returns whether or not the vector is empty.
+ bool is_empty() const { return length_ == 0; }
+
+ // Returns the pointer to the start of the data in the vector.
+ T* start() const { return start_; }
+
+ // Access individual vector elements - checks bounds in debug mode.
+ T& operator[](int index) const {
+ ASSERT(0 <= index && index < length_);
+ return start_[index];
+ }
+
+ T& first() { return start_[0]; }
+
+ T& last() { return start_[length_ - 1]; }
+
+ // Returns a clone of this vector with a new backing store.
+ Vector<T> Clone() const {
+ T* result = NewArray<T>(length_);
+ for (int i = 0; i < length_; i++) result[i] = start_[i];
+ return Vector<T>(result, length_);
+ }
+
+ void Sort(int (*cmp)(const T*, const T*)) {
+ typedef int (*RawComparer)(const void*, const void*);
+ qsort(start(),
+ length(),
+ sizeof(T),
+ reinterpret_cast<RawComparer>(cmp));
+ }
+
+ void Sort() {
+ Sort(PointerValueCompare<T>);
+ }
+
+ void Truncate(int length) {
+ ASSERT(length <= length_);
+ length_ = length;
+ }
+
+ // Releases the array underlying this vector. Once disposed the
+ // vector is empty.
+ void Dispose() {
+ if (is_empty()) return;
+ DeleteArray(start_);
+ start_ = NULL;
+ length_ = 0;
+ }
+
+ inline Vector<T> operator+(int offset) {
+ ASSERT(offset < length_);
+ return Vector<T>(start_ + offset, length_ - offset);
+ }
+
+ // Factory method for creating empty vectors.
+ static Vector<T> empty() { return Vector<T>(NULL, 0); }
+
+ protected:
+ void set_start(T* start) { start_ = start; }
+
+ private:
+ T* start_;
+ int length_;
+};
+
+
+// A temporary assignment sets a (non-local) variable to a value on
+// construction and resets it the value on destruction.
+template <typename T>
+class TempAssign {
+ public:
+ TempAssign(T* var, T value): var_(var), old_value_(*var) {
+ *var = value;
+ }
+
+ ~TempAssign() { *var_ = old_value_; }
+
+ private:
+ T* var_;
+ T old_value_;
+};
+
+
+template <typename T, int kSize>
+class EmbeddedVector : public Vector<T> {
+ public:
+ EmbeddedVector() : Vector<T>(buffer_, kSize) { }
+
+ // When copying, make underlying Vector to reference our buffer.
+ EmbeddedVector(const EmbeddedVector& rhs)
+ : Vector<T>(rhs) {
+ memcpy(buffer_, rhs.buffer_, sizeof(T) * kSize);
+ set_start(buffer_);
+ }
+
+ EmbeddedVector& operator=(const EmbeddedVector& rhs) {
+ if (this == &rhs) return *this;
+ Vector<T>::operator=(rhs);
+ memcpy(buffer_, rhs.buffer_, sizeof(T) * kSize);
+ set_start(buffer_);
+ return *this;
+ }
+
+ private:
+ T buffer_[kSize];
+};
+
+
+template <typename T>
+class ScopedVector : public Vector<T> {
+ public:
+ explicit ScopedVector(int length) : Vector<T>(NewArray<T>(length), length) { }
+ ~ScopedVector() {
+ DeleteArray(this->start());
+ }
+};
+
+
+inline Vector<const char> CStrVector(const char* data) {
+ return Vector<const char>(data, static_cast<int>(strlen(data)));
+}
+
+inline Vector<char> MutableCStrVector(char* data) {
+ return Vector<char>(data, static_cast<int>(strlen(data)));
+}
+
+inline Vector<char> MutableCStrVector(char* data, int max) {
+ int length = static_cast<int>(strlen(data));
+ return Vector<char>(data, (length < max) ? length : max);
+}
+
+template <typename T>
+inline Vector< Handle<Object> > HandleVector(v8::internal::Handle<T>* elms,
+ int length) {
+ return Vector< Handle<Object> >(
+ reinterpret_cast<v8::internal::Handle<Object>*>(elms), length);
+}
+
+
+// Simple support to read a file into a 0-terminated C-string.
+// The returned buffer must be freed by the caller.
+// On return, *exits tells whether the file existed.
+Vector<const char> ReadFile(const char* filename,
+ bool* exists,
+ bool verbose = true);
+
+
+// Simple wrapper that allows an ExternalString to refer to a
+// Vector<const char>. Doesn't assume ownership of the data.
+class AsciiStringAdapter: public v8::String::ExternalAsciiStringResource {
+ public:
+ explicit AsciiStringAdapter(Vector<const char> data) : data_(data) {}
+
+ virtual const char* data() const { return data_.start(); }
+
+ virtual size_t length() const { return data_.length(); }
+
+ private:
+ Vector<const char> data_;
+};
+
+
+// Helper class for building result strings in a character buffer. The
+// purpose of the class is to use safe operations that checks the
+// buffer bounds on all operations in debug mode.
+class StringBuilder {
+ public:
+ // Create a string builder with a buffer of the given size. The
+ // buffer is allocated through NewArray<char> and must be
+ // deallocated by the caller of Finalize().
+ explicit StringBuilder(int size);
+
+ StringBuilder(char* buffer, int size)
+ : buffer_(buffer, size), position_(0) { }
+
+ ~StringBuilder() { if (!is_finalized()) Finalize(); }
+
+ int size() const { return buffer_.length(); }
+
+ // Get the current position in the builder.
+ int position() const {
+ ASSERT(!is_finalized());
+ return position_;
+ }
+
+ // Reset the position.
+ void Reset() { position_ = 0; }
+
+ // Add a single character to the builder. It is not allowed to add
+ // 0-characters; use the Finalize() method to terminate the string
+ // instead.
+ void AddCharacter(char c) {
+ ASSERT(c != '\0');
+ ASSERT(!is_finalized() && position_ < buffer_.length());
+ buffer_[position_++] = c;
+ }
+
+ // Add an entire string to the builder. Uses strlen() internally to
+ // compute the length of the input string.
+ void AddString(const char* s);
+
+ // Add the first 'n' characters of the given string 's' to the
+ // builder. The input string must have enough characters.
+ void AddSubstring(const char* s, int n);
+
+ // Add formatted contents to the builder just like printf().
+ void AddFormatted(const char* format, ...);
+
+ // Add character padding to the builder. If count is non-positive,
+ // nothing is added to the builder.
+ void AddPadding(char c, int count);
+
+ // Finalize the string by 0-terminating it and returning the buffer.
+ char* Finalize();
+
+ private:
+ Vector<char> buffer_;
+ int position_;
+
+ bool is_finalized() const { return position_ < 0; }
+
+ DISALLOW_IMPLICIT_CONSTRUCTORS(StringBuilder);
+};
+
+
+// Copy from ASCII/16bit chars to ASCII/16bit chars.
+template <typename sourcechar, typename sinkchar>
+static inline void CopyChars(sinkchar* dest, const sourcechar* src, int chars) {
+ sinkchar* limit = dest + chars;
+#ifdef V8_HOST_CAN_READ_UNALIGNED
+ if (sizeof(*dest) == sizeof(*src)) {
+ // Number of characters in a uint32_t.
+ static const int kStepSize = sizeof(uint32_t) / sizeof(*dest); // NOLINT
+ while (dest <= limit - kStepSize) {
+ *reinterpret_cast<uint32_t*>(dest) =
+ *reinterpret_cast<const uint32_t*>(src);
+ dest += kStepSize;
+ src += kStepSize;
+ }
+ }
+#endif
+ while (dest < limit) {
+ *dest++ = static_cast<sinkchar>(*src++);
+ }
+}
+
+
+} } // namespace v8::internal
+
+#endif // V8_UTILS_H_