| Index: third_party/courgette/adjustment_method.cc
|
| ===================================================================
|
| --- third_party/courgette/adjustment_method.cc (revision 0)
|
| +++ third_party/courgette/adjustment_method.cc (revision 0)
|
| @@ -0,0 +1,703 @@
|
| +// Copyright (c) 2009 The Chromium Authors. All rights reserved.
|
| +// Use of this source code is governed by a BSD-style license that can be
|
| +// found in the LICENSE file.
|
| +
|
| +#include "third_party/courgette/adjustment_method.h"
|
| +
|
| +#include <algorithm>
|
| +#include <list>
|
| +#include <map>
|
| +#include <set>
|
| +#include <string>
|
| +#include <vector>
|
| +
|
| +#include "base/basictypes.h"
|
| +#include "base/logging.h"
|
| +#include "base/string_util.h"
|
| +
|
| +#include "third_party/courgette/assembly_program.h"
|
| +#include "third_party/courgette/courgette.h"
|
| +#include "third_party/courgette/encoded_program.h"
|
| +#include "third_party/courgette/image_info.h"
|
| +
|
| +namespace courgette {
|
| +
|
| +// We have three discretionary information logging levels for algorithm
|
| +// development. For now just configure with #defines.
|
| +// TODO(sra): make dependent of some configurable setting.
|
| +#define NO_LOG DLOG_IF(INFO, false)
|
| +// #define ALOG1 LOG(INFO)
|
| +// #define ALOG2 LOG(INFO)
|
| +// #define ALOG3 LOG(INFO)
|
| +#define ALOG1 NO_LOG
|
| +#define ALOG2 NO_LOG
|
| +#define ALOG3 NO_LOG
|
| +
|
| +////////////////////////////////////////////////////////////////////////////////
|
| +
|
| +class NullAdjustmentMethod : public AdjustmentMethod {
|
| + bool Adjust(const AssemblyProgram& model, AssemblyProgram* program) {
|
| + return true;
|
| + }
|
| +};
|
| +
|
| +////////////////////////////////////////////////////////////////////////////////
|
| +
|
| +// The purpose of adjustment is to assign indexes to Labels of a program 'p' to
|
| +// make the sequence of indexes similar to a 'model' program 'm'. Labels
|
| +// themselves don't have enough information to do this job, so we work with a
|
| +// LabelInfo surrogate for each label.
|
| +//
|
| +class LabelInfo {
|
| + public:
|
| + Label* label_; // The label that this info a surrogate for.
|
| +
|
| + // Information used only in debugging messages.
|
| + uint32 is_model_ : 1; // Is the label in the model?
|
| + uint32 debug_index_ : 31; // An unique small number for naming the label.
|
| +
|
| + uint32 refs_; // Number of times this Label is referenced.
|
| +
|
| + LabelInfo* assignment_; // Label from other program corresponding to this.
|
| +
|
| + // LabelInfos are in a doubly linked list ordered by address (label_->rva_) so
|
| + // we can quickly find Labels adjacent in address order.
|
| + LabelInfo* next_addr_; // Label(Info) at next highest address.
|
| + LabelInfo* prev_addr_; // Label(Info) at next lowest address.
|
| +
|
| + std::vector<uint32> positions_; // Offsets into the trace of references.
|
| +
|
| + // Just a no-argument constructor and copy constructor. Actual LabelInfo
|
| + // objects are allocated in std::pair structs in a std::map.
|
| + LabelInfo()
|
| + : label_(NULL), is_model_(false), debug_index_(0), refs_(0),
|
| + assignment_(NULL),
|
| + next_addr_(NULL),
|
| + prev_addr_(NULL) {}
|
| +
|
| + private:
|
| + void operator=(const LabelInfo*); // Disallow assignment only.
|
| +
|
| + // Public compiler generated copy constructor is needed to constuct
|
| + // std::pair<Label*, LabelInfo> so that fresh LabelInfos can be allocated
|
| + // inside a std::map.
|
| +};
|
| +
|
| +struct OrderLabelInfoByAddressAscending {
|
| + bool operator()(const LabelInfo* a, const LabelInfo* b) const {
|
| + return a->label_->rva_ < b->label_->rva_;
|
| + }
|
| +};
|
| +
|
| +static std::string ToString(LabelInfo* info) {
|
| + std::string s;
|
| + StringAppendF(&s, "%c%d", "pm"[info->is_model_], info->debug_index_);
|
| + if (info->label_->index_ != Label::kNoIndex)
|
| + StringAppendF(&s, " (%d)", info->label_->index_);
|
| +
|
| + StringAppendF(&s, " #%u", info->refs_);
|
| + return s;
|
| +}
|
| +
|
| +// General graph matching is exponential, essentially trying all permutations.
|
| +// The exponential algorithm can be made faster by avoiding consideration of
|
| +// impossible or unlikely matches. We can make the matching practical by eager
|
| +// matching - by looking for likely matches and commiting to them, and using the
|
| +// committed assignment as the basis for further matching.
|
| +//
|
| +// The basic eager graph-matching assignment is based on several ideas:
|
| +//
|
| +// * The strongest match will be for parts of the program that have not
|
| +// changed. If part of a program has not changed, then the number of
|
| +// references to a label will be the same, and corresponding pairs of
|
| +// adjacent labels will have the same RVA difference.
|
| +//
|
| +// * Some assignments are 'obvious' if you look at the distribution. Example:
|
| +// if both the program and the model have a label that is referred to much
|
| +// more often than the next most refered-to label, it is likely the two
|
| +// labels correspond.
|
| +//
|
| +// * If a label from the program corresponds to a label in the model, it is
|
| +// likely that the labels near the corresponding labels also match. A
|
| +// conservative way of extending the match is to assign only those labels
|
| +// which have exactly the same address offset and reference count.
|
| +//
|
| +// * If two labels correspond, then we can try to match up the references
|
| +// before and after the labels in the reference stream. For this to be
|
| +// practical, the number of references has to be small, e.g. each label has
|
| +// exactly one reference.
|
| +//
|
| +
|
| +// Note: we also tried a completely different approach: random assignment
|
| +// followed by simulated annealing. This produced similar results. The results
|
| +// were not as good for very small differences because the simulated annealing
|
| +// never quite hit the groove. And simulated annealing was several orders of
|
| +// magnitude slower.
|
| +
|
| +
|
| +// TRIE node for suffix strings in the label reference sequence.
|
| +//
|
| +// We dynamically build a trie for both the program and model, growing the trie
|
| +// as necessary. The trie node for a (possibly) empty string of label
|
| +// references contains the distribution of labels following the string. The
|
| +// roots node (for the empty string) thus contains the simple distribution of
|
| +// labels within the label reference stream.
|
| +
|
| +struct Node {
|
| + Node(LabelInfo* in_edge, Node* prev)
|
| + : in_edge_(in_edge), prev_(prev), count_(0),
|
| + in_queue_(false) {
|
| + length_ = 1 + (prev_ ? prev_->length_ : 0);
|
| + }
|
| + LabelInfo* in_edge_; //
|
| + Node* prev_; // Node at shorter length.
|
| + int count_; // Frequency of this path in Trie.
|
| + int length_;
|
| + typedef std::map<LabelInfo*, Node*> Edges;
|
| + Edges edges_;
|
| + std::vector<int> places_; // Indexes into sequence of this item.
|
| + std::list<Node*> edges_in_frequency_order;
|
| +
|
| + bool in_queue_;
|
| + bool Extended() const { return edges_.size() > 0; }
|
| +
|
| + uint32 Weight() const {
|
| + return edges_in_frequency_order.front()->count_;
|
| + }
|
| +};
|
| +
|
| +static std::string ToString(Node* node) {
|
| + std::vector<std::string> prefix;
|
| + for (Node* n = node; n->prev_; n = n->prev_)
|
| + prefix.push_back(ToString(n->in_edge_));
|
| +
|
| + std::string s;
|
| + s += "{";
|
| + const char* sep = "";
|
| + while (!prefix.empty()) {
|
| + s += sep;
|
| + sep = ",";
|
| + s += prefix.back();
|
| + prefix.pop_back();
|
| + }
|
| +
|
| + s += StringPrintf("%u", node->count_);
|
| + s += " @";
|
| + s += Uint64ToString(node->edges_in_frequency_order.size());
|
| + s += "}";
|
| + return s;
|
| +}
|
| +
|
| +typedef std::vector<LabelInfo*> Trace;
|
| +
|
| +struct OrderNodeByCountDecreasing {
|
| + bool operator()(Node* a, Node* b) const {
|
| + if (a->count_ != b->count_)
|
| + return (a->count_) > (b->count_);
|
| + return a->places_.at(0) < b->places_.at(0); // Prefer first occuring.
|
| + }
|
| +};
|
| +
|
| +struct OrderNodeByWeightDecreasing {
|
| + bool operator()(Node* a, Node* b) const {
|
| + // (Maybe tie-break on total count, followed by lowest assigned node indexes
|
| + // in path.)
|
| + uint32 a_weight = a->Weight();
|
| + uint32 b_weight = b->Weight();
|
| + if (a_weight != b_weight)
|
| + return a_weight > b_weight;
|
| + if (a->length_ != b->length_)
|
| + return a->length_ > b->length_; // Prefer longer.
|
| + return a->places_.at(0) < b->places_.at(0); // Prefer first occuring.
|
| + }
|
| +};
|
| +
|
| +typedef std::set<Node*, OrderNodeByWeightDecreasing> NodeQueue;
|
| +
|
| +class AssignmentProblem {
|
| + public:
|
| + AssignmentProblem(const Trace& model,
|
| + const Trace& problem)
|
| + : m_trace_(model),
|
| + p_trace_(problem) {
|
| + }
|
| +
|
| + ~AssignmentProblem() {
|
| + for (size_t i = 0; i < all_nodes_.size(); ++i)
|
| + delete all_nodes_[i];
|
| + }
|
| +
|
| + bool Solve() {
|
| + m_root_ = MakeRootNode(m_trace_);
|
| + p_root_ = MakeRootNode(p_trace_);
|
| + AddToQueue(p_root_);
|
| +
|
| + while (!worklist_.empty()) {
|
| + Node* node = *worklist_.begin();
|
| + node->in_queue_ = false;
|
| + worklist_.erase(node);
|
| + TrySolveNode(node);
|
| + }
|
| +
|
| + ALOG1 << unsolved_.size() << " unsolved items";
|
| + return true;
|
| + }
|
| +
|
| + private:
|
| + void AddToQueue(Node* node) {
|
| + if (node->length_ >= 10) {
|
| + ALOG3 << "Length clipped " << ToString(node->prev_);
|
| + return;
|
| + }
|
| + if (node->in_queue_) {
|
| + LOG(ERROR) << "Double add " << ToString(node);
|
| + return;
|
| + }
|
| + // just to be sure data for prioritizing is available
|
| + ExtendNode(node, p_trace_);
|
| + // SkipCommittedLabels(node);
|
| + if (node->edges_in_frequency_order.empty())
|
| + return;
|
| + node->in_queue_ = true;
|
| + worklist_.insert(node);
|
| + }
|
| +
|
| + void SkipCommittedLabels(Node* node) {
|
| + ExtendNode(node, p_trace_);
|
| + uint32 skipped = 0;
|
| + while (!node->edges_in_frequency_order.empty() &&
|
| + node->edges_in_frequency_order.front()->in_edge_->assignment_) {
|
| + ++skipped;
|
| + node->edges_in_frequency_order.pop_front();
|
| + }
|
| + if (skipped > 0)
|
| + ALOG3 << "Skipped " << skipped << " at " << ToString(node);
|
| + }
|
| +
|
| + void TrySolveNode(Node* p_node) {
|
| + Node* front = p_node->edges_in_frequency_order.front();
|
| + if (front->in_edge_->assignment_) {
|
| + p_node->edges_in_frequency_order.pop_front();
|
| + AddToQueue(front);
|
| + AddToQueue(p_node);
|
| + return;
|
| + }
|
| +
|
| + // Compare frequencies of unassigned edges, and either make
|
| + // assignment(s) or move node to unsolved list
|
| +
|
| + Node* m_node = FindModelNode(p_node);
|
| +
|
| + if (m_node == NULL) {
|
| + ALOG1 << "Can't find model node";
|
| + unsolved_.insert(p_node);
|
| + return;
|
| + }
|
| + ExtendNode(m_node, m_trace_);
|
| +
|
| + // Lets just try greedy
|
| +
|
| + SkipCommittedLabels(m_node);
|
| + if (m_node->edges_in_frequency_order.empty()) {
|
| + ALOG3 << "Punting, no elements left in model vs "
|
| + << p_node->edges_in_frequency_order.size();
|
| + unsolved_.insert(p_node);
|
| + return;
|
| + }
|
| + Node* m_match = m_node->edges_in_frequency_order.front();
|
| + Node* p_match = p_node->edges_in_frequency_order.front();
|
| +
|
| + if (p_match->count_ > 1.1 * m_match->count_ ||
|
| + m_match->count_ > 1.1 * p_match->count_) {
|
| + ALOG2 << "Tricky distribution "
|
| + << p_match->count_ << ":" << m_match->count_ << " "
|
| + << ToString(p_match) << " vs " << ToString(m_match);
|
| + return;
|
| + }
|
| +
|
| + m_node->edges_in_frequency_order.pop_front();
|
| + p_node->edges_in_frequency_order.pop_front();
|
| +
|
| + LabelInfo* p_label_info = p_match->in_edge_;
|
| + LabelInfo* m_label_info = m_match->in_edge_;
|
| + int m_index = p_label_info->label_->index_;
|
| + if (m_index != Label::kNoIndex) {
|
| + ALOG1 << "Cant use unassigned label from model " << m_index;
|
| + unsolved_.insert(p_node);
|
| + return;
|
| + }
|
| +
|
| + Assign(p_label_info, m_label_info);
|
| +
|
| + AddToQueue(p_match); // find matches within new match
|
| + AddToQueue(p_node); // and more matches within this node
|
| + }
|
| +
|
| + void Assign(LabelInfo* p_info, LabelInfo* m_info) {
|
| + AssignOne(p_info, m_info);
|
| + ALOG3 << "Assign " << ToString(p_info) << " := " << ToString(m_info);
|
| + // Now consider unassigned adjacent addresses
|
| + TryExtendAssignment(p_info, m_info);
|
| + }
|
| +
|
| + void AssignOne(LabelInfo* p_info, LabelInfo* m_info) {
|
| + p_info->label_->index_ = m_info->label_->index_;
|
| +
|
| + // Mark as assigned
|
| + m_info->assignment_ = p_info;
|
| + p_info->assignment_ = m_info;
|
| + }
|
| +
|
| + void TryExtendAssignment(LabelInfo* p_info, LabelInfo* m_info) {
|
| + RVA m_rva_base = m_info->label_->rva_;
|
| + RVA p_rva_base = p_info->label_->rva_;
|
| +
|
| + LabelInfo* m_info_next = m_info->next_addr_;
|
| + LabelInfo* p_info_next = p_info->next_addr_;
|
| + for ( ; m_info_next && p_info_next; ) {
|
| + if (m_info_next->assignment_)
|
| + break;
|
| +
|
| + RVA m_rva = m_info_next->label_->rva_;
|
| + RVA p_rva = p_info_next->label_->rva_;
|
| +
|
| + if (m_rva - m_rva_base != p_rva - p_rva_base) {
|
| + // previous label was pointing to something that is different size
|
| + break;
|
| + }
|
| + LabelInfo* m_info_next_next = m_info_next->next_addr_;
|
| + LabelInfo* p_info_next_next = p_info_next->next_addr_;
|
| + if (m_info_next_next && p_info_next_next) {
|
| + RVA m_rva_next = m_info_next_next->label_->rva_;
|
| + RVA p_rva_next = p_info_next_next->label_->rva_;
|
| + if (m_rva_next - m_rva != p_rva_next - p_rva) {
|
| + // Since following labels are no longer in address lockstep, assume
|
| + // this address has a difference.
|
| + break;
|
| + }
|
| + }
|
| +
|
| + // The label has inconsistent numbers of references, it is probably not
|
| + // the same thing.
|
| + if (m_info_next->refs_ != p_info_next->refs_) {
|
| + break;
|
| + }
|
| +
|
| + ALOG3 << " Extending assignment -> "
|
| + << ToString(p_info_next) << " := " << ToString(m_info_next);
|
| +
|
| + AssignOne(p_info_next, m_info_next);
|
| +
|
| + if (p_info_next->refs_ == m_info_next->refs_ &&
|
| + p_info_next->refs_ == 1) {
|
| + TryExtendSequence(p_info_next->positions_[0],
|
| + m_info_next->positions_[0]);
|
| + TryExtendSequenceBackwards(p_info_next->positions_[0],
|
| + m_info_next->positions_[0]);
|
| + }
|
| +
|
| + p_info_next = p_info_next_next;
|
| + m_info_next = m_info_next_next;
|
| + }
|
| +
|
| + LabelInfo* m_info_prev = m_info->prev_addr_;
|
| + LabelInfo* p_info_prev = p_info->prev_addr_;
|
| + for ( ; m_info_prev && p_info_prev; ) {
|
| + if (m_info_prev->assignment_)
|
| + break;
|
| +
|
| + RVA m_rva = m_info_prev->label_->rva_;
|
| + RVA p_rva = p_info_prev->label_->rva_;
|
| +
|
| + if (m_rva - m_rva_base != p_rva - p_rva_base) {
|
| + // previous label was pointing to something that is different size
|
| + break;
|
| + }
|
| + LabelInfo* m_info_prev_prev = m_info_prev->prev_addr_;
|
| + LabelInfo* p_info_prev_prev = p_info_prev->prev_addr_;
|
| +
|
| + // The the label has inconsistent numbers of references, it is
|
| + // probably not the same thing
|
| + if (m_info_prev->refs_ != p_info_prev->refs_) {
|
| + break;
|
| + }
|
| +
|
| + AssignOne(p_info_prev, m_info_prev);
|
| + ALOG3 << " Extending assignment <- " << ToString(p_info_prev) << " := "
|
| + << ToString(m_info_prev);
|
| +
|
| + p_info_prev = p_info_prev_prev;
|
| + m_info_prev = m_info_prev_prev;
|
| + }
|
| + }
|
| +
|
| + uint32 TryExtendSequence(uint32 p_pos_start, uint32 m_pos_start) {
|
| + uint32 p_pos = p_pos_start + 1;
|
| + uint32 m_pos = m_pos_start + 1;
|
| +
|
| + while (p_pos < p_trace_.size() && m_pos < m_trace_.size()) {
|
| + LabelInfo* p_info = p_trace_[p_pos];
|
| + LabelInfo* m_info = m_trace_[m_pos];
|
| +
|
| + // To match, either (1) both are assigned or (2) both are unassigned.
|
| + if ((p_info->assignment_ == NULL) != (m_info->assignment_ == NULL))
|
| + break;
|
| +
|
| + // If they are assigned, it needs to be consistent (same index).
|
| + if (p_info->assignment_ && m_info->assignment_) {
|
| + if (p_info->label_->index_ != m_info->label_->index_)
|
| + break;
|
| + ++p_pos;
|
| + ++m_pos;
|
| + continue;
|
| + }
|
| +
|
| + if (p_info->refs_ != m_info->refs_)
|
| + break;
|
| +
|
| + AssignOne(p_info, m_info);
|
| + ALOG3 << " Extending assignment seq"
|
| + << "[+" << p_pos - p_pos_start << "]"
|
| + << " -> "
|
| + << ToString(p_info) << " := " << ToString(m_info);
|
| +
|
| + ++p_pos;
|
| + ++m_pos;
|
| + }
|
| +
|
| + return p_pos - p_pos_start;
|
| + }
|
| +
|
| + uint32 TryExtendSequenceBackwards(uint32 p_pos_start, uint32 m_pos_start) {
|
| + if (p_pos_start == 0 || m_pos_start == 0)
|
| + return 0;
|
| +
|
| + uint32 p_pos = p_pos_start - 1;
|
| + uint32 m_pos = m_pos_start - 1;
|
| +
|
| + while (p_pos > 0 && m_pos > 0) {
|
| + LabelInfo* p_info = p_trace_[p_pos];
|
| + LabelInfo* m_info = m_trace_[m_pos];
|
| +
|
| + if ((p_info->assignment_ == NULL) != (m_info->assignment_ == NULL))
|
| + break;
|
| +
|
| + if (p_info->assignment_ && m_info->assignment_) {
|
| + if (p_info->label_->index_ != m_info->label_->index_)
|
| + break;
|
| + --p_pos;
|
| + --m_pos;
|
| + continue;
|
| + }
|
| +
|
| + if (p_info->refs_ != m_info->refs_)
|
| + break;
|
| +
|
| + AssignOne(p_info, m_info);
|
| + ALOG3 << " Extending assignment seq"
|
| + << "[-" << p_pos_start - p_pos << "]"
|
| + << " <- "
|
| + << ToString(p_info) << " := " << ToString(m_info);
|
| +
|
| + --p_pos;
|
| + --m_pos;
|
| + }
|
| +
|
| + return p_pos - p_pos_start;
|
| + }
|
| +
|
| + Node* FindModelNode(Node* node) {
|
| + if (node->prev_ == NULL)
|
| + return m_root_;
|
| +
|
| + Node* m_parent = FindModelNode(node->prev_);
|
| + if (m_parent == NULL) {
|
| + return NULL;
|
| + }
|
| +
|
| + ExtendNode(m_parent, m_trace_);
|
| +
|
| + LabelInfo* p_label = node->in_edge_;
|
| + LabelInfo* m_label = p_label->assignment_;
|
| + if (m_label == NULL) {
|
| + ALOG1 << "Expected assigned prefix";
|
| + return NULL;
|
| + }
|
| +
|
| + Node::Edges::iterator e = m_parent->edges_.find(m_label);
|
| + if (e == m_parent->edges_.end()) {
|
| + ALOG2 << "Expected defined edge in parent";
|
| + return NULL;
|
| + }
|
| +
|
| + return e->second;
|
| + }
|
| +
|
| + Node* MakeRootNode(const Trace& trace) {
|
| + Node* node = new Node(NULL, NULL);
|
| + all_nodes_.push_back(node);
|
| + for (size_t i = 0; i < trace.size(); ++i) {
|
| + ++node->count_;
|
| + node->places_.push_back(i);
|
| + }
|
| + return node;
|
| + }
|
| +
|
| + void ExtendNode(Node* node, const Trace& trace) {
|
| + // Make sure trie is filled in at this node.
|
| + if (node->Extended())
|
| + return;
|
| + for (size_t i = 0; i < node->places_.size(); ++i) {
|
| + uint32 index = node->places_.at(i);
|
| + if (index < trace.size()) {
|
| + LabelInfo* item = trace.at(index);
|
| + Node*& slot = node->edges_[item];
|
| + if (slot == NULL) {
|
| + slot = new Node(item, node);
|
| + all_nodes_.push_back(slot);
|
| + node->edges_in_frequency_order.push_back(slot);
|
| + }
|
| + slot->places_.push_back(index + 1);
|
| + ++slot->count_;
|
| + }
|
| + }
|
| + node->edges_in_frequency_order.sort(OrderNodeByCountDecreasing());
|
| + }
|
| +
|
| + const Trace& m_trace_;
|
| + const Trace& p_trace_;
|
| + Node* m_root_;
|
| + Node* p_root_;
|
| +
|
| + NodeQueue worklist_;
|
| + NodeQueue unsolved_;
|
| +
|
| + std::vector<Node*> all_nodes_;
|
| +
|
| + DISALLOW_COPY_AND_ASSIGN(AssignmentProblem);
|
| +};
|
| +
|
| +class GraphAdjuster : public AdjustmentMethod {
|
| + public:
|
| + GraphAdjuster() {}
|
| + ~GraphAdjuster() {}
|
| +
|
| + bool Adjust(const AssemblyProgram& model, AssemblyProgram* program) {
|
| + LOG(INFO) << "GraphAdjuster::Adjust";
|
| + prog_ = program;
|
| + model_ = &model;
|
| + debug_label_index_gen_ = 0;
|
| + return Finish();
|
| + }
|
| +
|
| + bool Finish() {
|
| + prog_->UnassignIndexes();
|
| + CollectTraces(model_, &model_abs32_, &model_rel32_, true);
|
| + CollectTraces(prog_, &prog_abs32_, &prog_rel32_, false);
|
| + Solve(model_abs32_, prog_abs32_);
|
| + Solve(model_rel32_, prog_rel32_);
|
| + prog_->AssignRemainingIndexes();
|
| + return true;
|
| + }
|
| +
|
| + private:
|
| +
|
| + void CollectTraces(const AssemblyProgram* program, Trace* abs32, Trace* rel32,
|
| + bool is_model) {
|
| + const std::vector<Instruction*>& instructions = program->instructions();
|
| + for (size_t i = 0; i < instructions.size(); ++i) {
|
| + Instruction* instruction = instructions.at(i);
|
| + if (Label* label = program->InstructionAbs32Label(instruction))
|
| + ReferenceLabel(abs32, label, is_model);
|
| + if (Label* label = program->InstructionRel32Label(instruction))
|
| + ReferenceLabel(rel32, label, is_model);
|
| + }
|
| + // TODO(sra): we could simply append all the labels in index order to
|
| + // incorporate some costing for entropy (bigger deltas) that will be
|
| + // introduced into the label address table by non-monotonic ordering. This
|
| + // would have some knock-on effects to parts of the algorithm that work on
|
| + // single-occurence labels.
|
| + }
|
| +
|
| + void Solve(const Trace& model, const Trace& problem) {
|
| + LinkLabelInfos(model);
|
| + LinkLabelInfos(problem);
|
| + AssignmentProblem a(model, problem);
|
| + a.Solve();
|
| + }
|
| +
|
| + void LinkLabelInfos(const Trace& trace) {
|
| + typedef std::set<LabelInfo*, OrderLabelInfoByAddressAscending> Ordered;
|
| + Ordered ordered;
|
| + for (Trace::const_iterator p = trace.begin(); p != trace.end(); ++p)
|
| + ordered.insert(*p);
|
| + LabelInfo* prev = NULL;
|
| + for (Ordered::iterator p = ordered.begin(); p != ordered.end(); ++p) {
|
| + LabelInfo* curr = *p;
|
| + if (prev) prev->next_addr_ = curr;
|
| + curr->prev_addr_ = prev;
|
| + prev = curr;
|
| +
|
| + if (curr->positions_.size() != curr->refs_)
|
| + NOTREACHED();
|
| + }
|
| + }
|
| +
|
| + void ReferenceLabel(Trace* trace, Label* label, bool is_model) {
|
| + trace->push_back(MakeLabelInfo(label, is_model, trace->size()));
|
| + }
|
| +
|
| + LabelInfo* MakeLabelInfo(Label* label, bool is_model, uint32 position) {
|
| + LabelInfo& slot = label_infos_[label];
|
| + if (slot.label_ == NULL) {
|
| + slot.label_ = label;
|
| + slot.is_model_ = is_model;
|
| + slot.debug_index_ = ++debug_label_index_gen_;
|
| + }
|
| + slot.positions_.push_back(position);
|
| + ++slot.refs_;
|
| + return &slot;
|
| + }
|
| +
|
| + AssemblyProgram* prog_; // Program to be adjusted, owned by caller.
|
| + const AssemblyProgram* model_; // Program to be mimicked, owned by caller.
|
| +
|
| + Trace model_abs32_;
|
| + Trace model_rel32_;
|
| + Trace prog_abs32_;
|
| + Trace prog_rel32_;
|
| +
|
| + int debug_label_index_gen_;
|
| +
|
| + // Note LabelInfo is allocated inside map, so the LabelInfo lifetimes are
|
| + // managed by the map.
|
| + std::map<Label*, LabelInfo> label_infos_;
|
| +
|
| + private:
|
| + DISALLOW_COPY_AND_ASSIGN(GraphAdjuster);
|
| +};
|
| +
|
| +
|
| +////////////////////////////////////////////////////////////////////////////////
|
| +
|
| +void AdjustmentMethod::Destroy() { delete this; }
|
| +
|
| +AdjustmentMethod* AdjustmentMethod::MakeNullAdjustmentMethod() {
|
| + return new NullAdjustmentMethod();
|
| +}
|
| +
|
| +AdjustmentMethod* AdjustmentMethod::MakeProductionAdjustmentMethod() {
|
| + return new GraphAdjuster();
|
| +}
|
| +
|
| +Status Adjust(const AssemblyProgram& model, AssemblyProgram* program) {
|
| + AdjustmentMethod* method = AdjustmentMethod::MakeProductionAdjustmentMethod();
|
| + bool ok = method->Adjust(model, program);
|
| + method->Destroy();
|
| + if (ok)
|
| + return C_OK;
|
| + else
|
| + return C_ADJUSTMENT_FAILED;
|
| +}
|
| +
|
| +} // namespace courgette
|
|
|