Version 2.5.5
Added more aggressive GC of external objects in near out-of-memory situations.
Fixed a bug that gave the incorrect result for String.split called on the empty string (issue 924).
git-svn-id: http://v8.googlecode.com/svn/trunk@5780 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
diff --git a/src/utils.h b/src/utils.h
index ffdb639..069be4f 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -31,6 +31,8 @@
#include <stdlib.h>
#include <string.h>
+#include "checks.h"
+
namespace v8 {
namespace internal {
@@ -142,7 +144,19 @@
// 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);
+// Implementation is from "Hacker's Delight" by Henry S. Warren, Jr.,
+// figure 3-3, page 48, where the function is called clp2.
+static inline uint32_t RoundUpToPowerOf2(uint32_t x) {
+ ASSERT(x <= 0x80000000u);
+ x = x - 1;
+ x = x | (x >> 1);
+ x = x | (x >> 2);
+ x = x | (x >> 4);
+ x = x | (x >> 8);
+ x = x | (x >> 16);
+ return x + 1;
+}
+
template <typename T>
@@ -216,65 +230,18 @@
// ----------------------------------------------------------------------------
// Hash function.
-uint32_t ComputeIntegerHash(uint32_t key);
-
-
-// ----------------------------------------------------------------------------
-// I/O support.
-
-#if __GNUC__ >= 4
-// On gcc we can ask the compiler to check the types of %d-style format
-// specifiers and their associated arguments. TODO(erikcorry) fix this
-// so it works on MacOSX.
-#if defined(__MACH__) && defined(__APPLE__)
-#define PRINTF_CHECKING
-#else // MacOsX.
-#define PRINTF_CHECKING __attribute__ ((format (printf, 1, 2)))
-#endif
-#else
-#define PRINTF_CHECKING
-#endif
-
-// Our version of printf().
-void PRINTF_CHECKING 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);
+// Thomas Wang, Integer Hash Functions.
+// http://www.concentric.net/~Ttwang/tech/inthash.htm
+static inline uint32_t ComputeIntegerHash(uint32_t key) {
+ uint32_t hash = key;
+ hash = ~hash + (hash << 15); // hash = (hash << 15) - hash - 1;
+ hash = hash ^ (hash >> 12);
+ hash = hash + (hash << 2);
+ hash = hash ^ (hash >> 4);
+ hash = hash * 2057; // hash = (hash + (hash << 3)) + (hash << 11);
+ hash = hash ^ (hash >> 16);
+ return hash;
+}
// ----------------------------------------------------------------------------
@@ -416,23 +383,6 @@
};
-// 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:
@@ -484,13 +434,6 @@
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);
-}
-
/*
* A class that collects values into a backing store.
@@ -699,156 +642,6 @@
};
-// 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);
-};
-
-
-// Custom memcpy implementation for platforms where the standard version
-// may not be good enough.
-// TODO(lrn): Check whether some IA32 platforms should be excluded.
-#if defined(V8_TARGET_ARCH_IA32)
-
-// TODO(lrn): Extend to other platforms as needed.
-
-typedef void (*MemCopyFunction)(void* dest, const void* src, size_t size);
-
-// Implemented in codegen-<arch>.cc.
-MemCopyFunction CreateMemCopyFunction();
-
-// Copy memory area to disjoint memory area.
-static inline void MemCopy(void* dest, const void* src, size_t size) {
- static MemCopyFunction memcopy = CreateMemCopyFunction();
- (*memcopy)(dest, src, size);
-#ifdef DEBUG
- CHECK_EQ(0, memcmp(dest, src, size));
-#endif
-}
-
-
-// Limit below which the extra overhead of the MemCopy function is likely
-// to outweigh the benefits of faster copying.
-// TODO(lrn): Try to find a more precise value.
-static const int kMinComplexMemCopy = 64;
-
-#else // V8_TARGET_ARCH_IA32
-
-static inline void MemCopy(void* dest, const void* src, size_t size) {
- memcpy(dest, src, size);
-}
-
-static const int kMinComplexMemCopy = 256;
-
-#endif // V8_TARGET_ARCH_IA32
-
-
-// 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)) {
- if (chars >= static_cast<int>(kMinComplexMemCopy / sizeof(*dest))) {
- MemCopy(dest, src, chars * sizeof(*dest));
- return;
- }
- // Number of characters in a uintptr_t.
- static const int kStepSize = sizeof(uintptr_t) / sizeof(*dest); // NOLINT
- while (dest <= limit - kStepSize) {
- *reinterpret_cast<uintptr_t*>(dest) =
- *reinterpret_cast<const uintptr_t*>(src);
- dest += kStepSize;
- src += kStepSize;
- }
- }
-#endif
- while (dest < limit) {
- *dest++ = static_cast<sinkchar>(*src++);
- }
-}
-
-
// Compare ASCII/16bit chars to ASCII/16bit chars.
template <typename lchar, typename rchar>
static inline int CompareChars(const lchar* lhs, const rchar* rhs, int chars) {
@@ -877,54 +670,14 @@
}
-template <typename T>
-static inline void MemsetPointer(T** dest, T* value, int counter) {
-#if defined(V8_HOST_ARCH_IA32)
-#define STOS "stosl"
-#elif defined(V8_HOST_ARCH_X64)
-#define STOS "stosq"
-#endif
-
-#if defined(__GNUC__) && defined(STOS)
- asm volatile(
- "cld;"
- "rep ; " STOS
- : "+&c" (counter), "+&D" (dest)
- : "a" (value)
- : "memory", "cc");
-#else
- for (int i = 0; i < counter; i++) {
- dest[i] = value;
- }
-#endif
-
-#undef STOS
-}
-
-
-// Copies data from |src| to |dst|. The data spans MUST not overlap.
-inline void CopyWords(Object** dst, Object** src, int num_words) {
- ASSERT(Min(dst, src) + num_words <= Max(dst, src));
- ASSERT(num_words > 0);
-
- // Use block copying memcpy if the segment we're copying is
- // enough to justify the extra call/setup overhead.
- static const int kBlockCopyLimit = 16;
-
- if (num_words >= kBlockCopyLimit) {
- memcpy(dst, src, num_words * kPointerSize);
- } else {
- int remaining = num_words;
- do {
- remaining--;
- *dst++ = *src++;
- } while (remaining > 0);
- }
-}
-
-
// Calculate 10^exponent.
-int TenToThe(int exponent);
+static inline int TenToThe(int exponent) {
+ ASSERT(exponent <= 9);
+ ASSERT(exponent >= 1);
+ int answer = 10;
+ for (int i = 1; i < exponent; i++) answer *= 10;
+ return answer;
+}
// The type-based aliasing rule allows the compiler to assume that pointers of