+++ /dev/null
-// Copyright (c) 2005, Google Inc.
-// 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.
-
-// ---
-// Author: Sanjay Ghemawat <opensource@google.com>
-//
-// A data structure used by the caching malloc. It maps from page# to
-// a pointer that contains info about that page. We use two
-// representations: one for 32-bit addresses, and another for 64 bit
-// addresses. Both representations provide the same interface. The
-// first representation is implemented as a flat array, the seconds as
-// a three-level radix tree that strips away approximately 1/3rd of
-// the bits every time.
-//
-// The BITS parameter should be the number of bits required to hold
-// a page number. E.g., with 32 bit pointers and 4K pages (i.e.,
-// page offset fits in lower 12 bits), BITS == 20.
-
-#ifndef TCMALLOC_PAGEMAP_H__
-#define TCMALLOC_PAGEMAP_H__
-
-#if HAVE(STDINT_H)
-#include <stdint.h>
-#elif HAVE(INTTYPES_H)
-#include <inttypes.h>
-#else
-#include <sys/types.h>
-#endif
-
-#include <string.h>
-#include "Assertions.h"
-
-// Single-level array
-template <int BITS>
-class TCMalloc_PageMap1 {
- private:
- void** array_;
-
- public:
- typedef uintptr_t Number;
-
- void init(void* (*allocator)(size_t)) {
- array_ = reinterpret_cast<void**>((*allocator)(sizeof(void*) << BITS));
- memset(array_, 0, sizeof(void*) << BITS);
- }
-
- // Ensure that the map contains initialized entries "x .. x+n-1".
- // Returns true if successful, false if we could not allocate memory.
- bool Ensure(Number, size_t) {
- // Nothing to do since flat array was allocate at start
- return true;
- }
-
- void PreallocateMoreMemory() {}
-
- // REQUIRES "k" is in range "[0,2^BITS-1]".
- // REQUIRES "k" has been ensured before.
- //
- // Return the current value for KEY. Returns "Value()" if not
- // yet set.
- void* get(Number k) const {
- return array_[k];
- }
-
- // REQUIRES "k" is in range "[0,2^BITS-1]".
- // REQUIRES "k" has been ensured before.
- //
- // Sets the value for KEY.
- void set(Number k, void* v) {
- array_[k] = v;
- }
-};
-
-// Two-level radix tree
-template <int BITS>
-class TCMalloc_PageMap2 {
- private:
- // Put 32 entries in the root and (2^BITS)/32 entries in each leaf.
- static const int ROOT_BITS = 5;
- static const int ROOT_LENGTH = 1 << ROOT_BITS;
-
- static const int LEAF_BITS = BITS - ROOT_BITS;
- static const int LEAF_LENGTH = 1 << LEAF_BITS;
-
- // Leaf node
- struct Leaf {
- void* values[LEAF_LENGTH];
- };
-
- Leaf* root_[ROOT_LENGTH]; // Pointers to 32 child nodes
- void* (*allocator_)(size_t); // Memory allocator
-
- public:
- typedef uintptr_t Number;
-
- void init(void* (*allocator)(size_t)) {
- allocator_ = allocator;
- memset(root_, 0, sizeof(root_));
- }
-
- void* get(Number k) const {
- ASSERT(k >> BITS == 0);
- const Number i1 = k >> LEAF_BITS;
- const Number i2 = k & (LEAF_LENGTH-1);
- return root_[i1]->values[i2];
- }
-
- void set(Number k, void* v) {
- ASSERT(k >> BITS == 0);
- const Number i1 = k >> LEAF_BITS;
- const Number i2 = k & (LEAF_LENGTH-1);
- root_[i1]->values[i2] = v;
- }
-
- bool Ensure(Number start, size_t n) {
- for (Number key = start; key <= start + n - 1; ) {
- const Number i1 = key >> LEAF_BITS;
-
- // Make 2nd level node if necessary
- if (root_[i1] == NULL) {
- Leaf* leaf = reinterpret_cast<Leaf*>((*allocator_)(sizeof(Leaf)));
- if (leaf == NULL) return false;
- memset(leaf, 0, sizeof(*leaf));
- root_[i1] = leaf;
- }
-
- // Advance key past whatever is covered by this leaf node
- key = ((key >> LEAF_BITS) + 1) << LEAF_BITS;
- }
- return true;
- }
-
- void PreallocateMoreMemory() {
- // Allocate enough to keep track of all possible pages
- Ensure(0, 1 << BITS);
- }
-
-#ifdef WTF_CHANGES
- template<class Visitor, class MemoryReader>
- void visitValues(Visitor& visitor, const MemoryReader& reader)
- {
- for (int i = 0; i < ROOT_LENGTH; i++) {
- if (!root_[i])
- continue;
-
- Leaf* l = reader(reinterpret_cast<Leaf*>(root_[i]));
- for (int j = 0; j < LEAF_LENGTH; j += visitor.visit(l->values[j]))
- ;
- }
- }
-
- template<class Visitor, class MemoryReader>
- void visitAllocations(Visitor& visitor, const MemoryReader&) {
- for (int i = 0; i < ROOT_LENGTH; i++) {
- if (root_[i])
- visitor.visit(root_[i], sizeof(Leaf));
- }
- }
-#endif
-};
-
-// Three-level radix tree
-template <int BITS>
-class TCMalloc_PageMap3 {
- private:
- // How many bits should we consume at each interior level
- static const int INTERIOR_BITS = (BITS + 2) / 3; // Round-up
- static const int INTERIOR_LENGTH = 1 << INTERIOR_BITS;
-
- // How many bits should we consume at leaf level
- static const int LEAF_BITS = BITS - 2*INTERIOR_BITS;
- static const int LEAF_LENGTH = 1 << LEAF_BITS;
-
- // Interior node
- struct Node {
- Node* ptrs[INTERIOR_LENGTH];
- };
-
- // Leaf node
- struct Leaf {
- void* values[LEAF_LENGTH];
- };
-
- Node* root_; // Root of radix tree
- void* (*allocator_)(size_t); // Memory allocator
-
- Node* NewNode() {
- Node* result = reinterpret_cast<Node*>((*allocator_)(sizeof(Node)));
- if (result != NULL) {
- memset(result, 0, sizeof(*result));
- }
- return result;
- }
-
- public:
- typedef uintptr_t Number;
-
- void init(void* (*allocator)(size_t)) {
- allocator_ = allocator;
- root_ = NewNode();
- }
-
- void* get(Number k) const {
- ASSERT(k >> BITS == 0);
- const Number i1 = k >> (LEAF_BITS + INTERIOR_BITS);
- const Number i2 = (k >> LEAF_BITS) & (INTERIOR_LENGTH-1);
- const Number i3 = k & (LEAF_LENGTH-1);
- return reinterpret_cast<Leaf*>(root_->ptrs[i1]->ptrs[i2])->values[i3];
- }
-
- void set(Number k, void* v) {
- ASSERT(k >> BITS == 0);
- const Number i1 = k >> (LEAF_BITS + INTERIOR_BITS);
- const Number i2 = (k >> LEAF_BITS) & (INTERIOR_LENGTH-1);
- const Number i3 = k & (LEAF_LENGTH-1);
- reinterpret_cast<Leaf*>(root_->ptrs[i1]->ptrs[i2])->values[i3] = v;
- }
-
- bool Ensure(Number start, size_t n) {
- for (Number key = start; key <= start + n - 1; ) {
- const Number i1 = key >> (LEAF_BITS + INTERIOR_BITS);
- const Number i2 = (key >> LEAF_BITS) & (INTERIOR_LENGTH-1);
-
- // Make 2nd level node if necessary
- if (root_->ptrs[i1] == NULL) {
- Node* n = NewNode();
- if (n == NULL) return false;
- root_->ptrs[i1] = n;
- }
-
- // Make leaf node if necessary
- if (root_->ptrs[i1]->ptrs[i2] == NULL) {
- Leaf* leaf = reinterpret_cast<Leaf*>((*allocator_)(sizeof(Leaf)));
- if (leaf == NULL) return false;
- memset(leaf, 0, sizeof(*leaf));
- root_->ptrs[i1]->ptrs[i2] = reinterpret_cast<Node*>(leaf);
- }
-
- // Advance key past whatever is covered by this leaf node
- key = ((key >> LEAF_BITS) + 1) << LEAF_BITS;
- }
- return true;
- }
-
- void PreallocateMoreMemory() {
- }
-
-#ifdef WTF_CHANGES
- template<class Visitor, class MemoryReader>
- void visitValues(Visitor& visitor, const MemoryReader& reader) {
- Node* root = reader(root_);
- for (int i = 0; i < INTERIOR_LENGTH; i++) {
- if (!root->ptrs[i])
- continue;
-
- Node* n = reader(root->ptrs[i]);
- for (int j = 0; j < INTERIOR_LENGTH; j++) {
- if (!n->ptrs[j])
- continue;
-
- Leaf* l = reader(reinterpret_cast<Leaf*>(n->ptrs[j]));
- for (int k = 0; k < LEAF_LENGTH; k += visitor.visit(l->values[k]))
- ;
- }
- }
- }
-
- template<class Visitor, class MemoryReader>
- void visitAllocations(Visitor& visitor, const MemoryReader& reader) {
- visitor.visit(root_, sizeof(Node));
-
- Node* root = reader(root_);
- for (int i = 0; i < INTERIOR_LENGTH; i++) {
- if (!root->ptrs[i])
- continue;
-
- visitor.visit(root->ptrs[i], sizeof(Node));
- Node* n = reader(root->ptrs[i]);
- for (int j = 0; j < INTERIOR_LENGTH; j++) {
- if (!n->ptrs[j])
- continue;
-
- visitor.visit(n->ptrs[j], sizeof(Leaf));
- }
- }
- }
-#endif
-};
-
-#endif // TCMALLOC_PAGEMAP_H__
projects / apple / javascriptcore.git / blobdiff