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| author | dim <dim@FreeBSD.org> | 2014-03-21 17:53:59 +0000 |
|---|---|---|
| committer | dim <dim@FreeBSD.org> | 2014-03-21 17:53:59 +0000 |
| commit | 9cedb8bb69b89b0f0c529937247a6a80cabdbaec (patch) | |
| tree | c978f0e9ec1ab92dc8123783f30b08a7fd1e2a39 /contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp | |
| parent | 03fdc2934eb61c44c049a02b02aa974cfdd8a0eb (diff) | |
| download | FreeBSD-src-9cedb8bb69b89b0f0c529937247a6a80cabdbaec.zip FreeBSD-src-9cedb8bb69b89b0f0c529937247a6a80cabdbaec.tar.gz | |
MFC 261991:
Upgrade our copy of llvm/clang to 3.4 release. This version supports
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.
The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3. The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.
Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>
MFC 262121 (by emaste):
Update lldb for clang/llvm 3.4 import
This commit largely restores the lldb source to the upstream r196259
snapshot with the addition of threaded inferior support and a few bug
fixes.
Specific upstream lldb revisions restored include:
SVN git
181387 779e6ac
181703 7bef4e2
182099 b31044e
182650 f2dcf35
182683 0d91b80
183862 15c1774
183929 99447a6
184177 0b2934b
184948 4dc3761
184954 007e7bc
186990 eebd175
Sponsored by: DARPA, AFRL
MFC 262186 (by emaste):
Fix mismerge in r262121
A break statement was lost in the merge. The error had no functional
impact, but restore it to reduce the diff against upstream.
MFC 262303:
Pull in r197521 from upstream clang trunk (by rdivacky):
Use the integrated assembler by default on FreeBSD/ppc and ppc64.
Requested by: jhibbits
MFC 262611:
Pull in r196874 from upstream llvm trunk:
Fix a crash that occurs when PWD is invalid.
MCJIT needs to be able to run in hostile environments, even when PWD
is invalid. There's no need to crash MCJIT in this case.
The obvious fix is to simply leave MCContext's CompilationDir empty
when PWD can't be determined. This way, MCJIT clients,
and other clients that link with LLVM don't need a valid working directory.
If we do want to guarantee valid CompilationDir, that should be done
only for clients of getCompilationDir(). This is as simple as checking
for an empty string.
The only current use of getCompilationDir is EmitGenDwarfInfo, which
won't conceivably run with an invalid working dir. However, in the
purely hypothetically and untestable case that this happens, the
AT_comp_dir will be omitted from the compilation_unit DIE.
This should help fix assertions occurring with ports-mgmt/tinderbox,
when it is using jails, and sometimes invalidates clang's current
working directory.
Reported by: decke
MFC 262809:
Pull in r203007 from upstream clang trunk:
Don't produce an alias between destructors with different calling conventions.
Fixes pr19007.
(Please note that is an LLVM PR identifier, not a FreeBSD one.)
This should fix Firefox and/or libxul crashes (due to problems with
regparm/stdcall calling conventions) on i386.
Reported by: multiple users on freebsd-current
PR: bin/187103
MFC 263048:
Repair recognition of "CC" as an alias for the C++ compiler, since it
was silently broken by upstream for a Windows-specific use-case.
Apparently some versions of CMake still rely on this archaic feature...
Reported by: rakuco
MFC 263049:
Garbage collect the old way of adding the libstdc++ include directories
in clang's InitHeaderSearch.cpp. This has been superseded by David
Chisnall's commit in r255321.
Moreover, if libc++ is used, the libstdc++ include directories should
not be in the search path at all. These directories are now only used
if you pass -stdlib=libstdc++.
Diffstat (limited to 'contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp | 1424 |
1 files changed, 0 insertions, 1424 deletions
diff --git a/contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp b/contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp deleted file mode 100644 index 7de7326..0000000 --- a/contrib/llvm/lib/Transforms/Instrumentation/PathProfiling.cpp +++ /dev/null @@ -1,1424 +0,0 @@ -//===- PathProfiling.cpp - Inserts counters for path profiling ------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This pass instruments functions for Ball-Larus path profiling. Ball-Larus -// profiling converts the CFG into a DAG by replacing backedges with edges -// from entry to the start block and from the end block to exit. The paths -// along the new DAG are enumrated, i.e. each path is given a path number. -// Edges are instrumented to increment the path number register, such that the -// path number register will equal the path number of the path taken at the -// exit. -// -// This file defines classes for building a CFG for use with different stages -// in the Ball-Larus path profiling instrumentation [Ball96]. The -// requirements are formatting the llvm CFG into the Ball-Larus DAG, path -// numbering, finding a spanning tree, moving increments from the spanning -// tree to chords. -// -// Terms: -// DAG - Directed Acyclic Graph. -// Ball-Larus DAG - A CFG with an entry node, an exit node, and backedges -// removed in the following manner. For every backedge -// v->w, insert edge ENTRY->w and edge v->EXIT. -// Path Number - The number corresponding to a specific path through a -// Ball-Larus DAG. -// Spanning Tree - A subgraph, S, is a spanning tree if S covers all -// vertices and is a tree. -// Chord - An edge not in the spanning tree. -// -// [Ball96] -// T. Ball and J. R. Larus. "Efficient Path Profiling." -// International Symposium on Microarchitecture, pages 46-57, 1996. -// http://portal.acm.org/citation.cfm?id=243857 -// -// [Ball94] -// Thomas Ball. "Efficiently Counting Program Events with Support for -// On-line queries." -// ACM Transactions on Programmmg Languages and Systems, Vol 16, No 5, -// September 1994, Pages 1399-1410. -//===----------------------------------------------------------------------===// -#define DEBUG_TYPE "insert-path-profiling" - -#include "llvm/Transforms/Instrumentation.h" -#include "ProfilingUtils.h" -#include "llvm/Analysis/PathNumbering.h" -#include "llvm/IR/Constants.h" -#include "llvm/IR/DerivedTypes.h" -#include "llvm/IR/InstrTypes.h" -#include "llvm/IR/Instructions.h" -#include "llvm/IR/LLVMContext.h" -#include "llvm/IR/Module.h" -#include "llvm/IR/TypeBuilder.h" -#include "llvm/Pass.h" -#include "llvm/Support/CFG.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/Compiler.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/raw_ostream.h" -#include "llvm/Transforms/Utils/BasicBlockUtils.h" -#include <vector> - -#define HASH_THRESHHOLD 100000 - -using namespace llvm; - -namespace { -class BLInstrumentationNode; -class BLInstrumentationEdge; -class BLInstrumentationDag; - -// --------------------------------------------------------------------------- -// BLInstrumentationNode extends BallLarusNode with member used by the -// instrumentation algortihms. -// --------------------------------------------------------------------------- -class BLInstrumentationNode : public BallLarusNode { -public: - // Creates a new BLInstrumentationNode from a BasicBlock. - BLInstrumentationNode(BasicBlock* BB); - - // Get/sets the Value corresponding to the pathNumber register, - // constant or phinode. Used by the instrumentation code to remember - // path number Values. - Value* getStartingPathNumber(); - void setStartingPathNumber(Value* pathNumber); - - Value* getEndingPathNumber(); - void setEndingPathNumber(Value* pathNumber); - - // Get/set the PHINode Instruction for this node. - PHINode* getPathPHI(); - void setPathPHI(PHINode* pathPHI); - -private: - - Value* _startingPathNumber; // The Value for the current pathNumber. - Value* _endingPathNumber; // The Value for the current pathNumber. - PHINode* _pathPHI; // The PHINode for current pathNumber. -}; - -// -------------------------------------------------------------------------- -// BLInstrumentationEdge extends BallLarusEdge with data about the -// instrumentation that will end up on each edge. -// -------------------------------------------------------------------------- -class BLInstrumentationEdge : public BallLarusEdge { -public: - BLInstrumentationEdge(BLInstrumentationNode* source, - BLInstrumentationNode* target); - - // Sets the target node of this edge. Required to split edges. - void setTarget(BallLarusNode* node); - - // Get/set whether edge is in the spanning tree. - bool isInSpanningTree() const; - void setIsInSpanningTree(bool isInSpanningTree); - - // Get/ set whether this edge will be instrumented with a path number - // initialization. - bool isInitialization() const; - void setIsInitialization(bool isInitialization); - - // Get/set whether this edge will be instrumented with a path counter - // increment. Notice this is incrementing the path counter - // corresponding to the path number register. The path number - // increment is determined by getIncrement(). - bool isCounterIncrement() const; - void setIsCounterIncrement(bool isCounterIncrement); - - // Get/set the path number increment that this edge will be instrumented - // with. This is distinct from the path counter increment and the - // weight. The counter increment counts the number of executions of - // some path, whereas the path number keeps track of which path number - // the program is on. - long getIncrement() const; - void setIncrement(long increment); - - // Get/set whether the edge has been instrumented. - bool hasInstrumentation(); - void setHasInstrumentation(bool hasInstrumentation); - - // Returns the successor number of this edge in the source. - unsigned getSuccessorNumber(); - -private: - // The increment that the code will be instrumented with. - long long _increment; - - // Whether this edge is in the spanning tree. - bool _isInSpanningTree; - - // Whether this edge is an initialiation of the path number. - bool _isInitialization; - - // Whether this edge is a path counter increment. - bool _isCounterIncrement; - - // Whether this edge has been instrumented. - bool _hasInstrumentation; -}; - -// --------------------------------------------------------------------------- -// BLInstrumentationDag extends BallLarusDag with algorithms that -// determine where instrumentation should be placed. -// --------------------------------------------------------------------------- -class BLInstrumentationDag : public BallLarusDag { -public: - BLInstrumentationDag(Function &F); - - // Returns the Exit->Root edge. This edge is required for creating - // directed cycles in the algorithm for moving instrumentation off of - // the spanning tree - BallLarusEdge* getExitRootEdge(); - - // Returns an array of phony edges which mark those nodes - // with function calls - BLEdgeVector getCallPhonyEdges(); - - // Gets/sets the path counter array - GlobalVariable* getCounterArray(); - void setCounterArray(GlobalVariable* c); - - // Calculates the increments for the chords, thereby removing - // instrumentation from the spanning tree edges. Implementation is based - // on the algorithm in Figure 4 of [Ball94] - void calculateChordIncrements(); - - // Updates the state when an edge has been split - void splitUpdate(BLInstrumentationEdge* formerEdge, BasicBlock* newBlock); - - // Calculates a spanning tree of the DAG ignoring cycles. Whichever - // edges are in the spanning tree will not be instrumented, but this - // implementation does not try to minimize the instrumentation overhead - // by trying to find hot edges. - void calculateSpanningTree(); - - // Pushes initialization further down in order to group the first - // increment and initialization. - void pushInitialization(); - - // Pushes the path counter increments up in order to group the last path - // number increment. - void pushCounters(); - - // Removes phony edges from the successor list of the source, and the - // predecessor list of the target. - void unlinkPhony(); - - // Generate dot graph for the function - void generateDotGraph(); - -protected: - // BLInstrumentationDag creates BLInstrumentationNode objects in this - // method overriding the creation of BallLarusNode objects. - // - // Allows subclasses to determine which type of Node is created. - // Override this method to produce subclasses of BallLarusNode if - // necessary. - virtual BallLarusNode* createNode(BasicBlock* BB); - - // BLInstrumentationDag create BLInstrumentationEdges. - // - // Allows subclasses to determine which type of Edge is created. - // Override this method to produce subclasses of BallLarusEdge if - // necessary. Parameters source and target will have been created by - // createNode and can be cast to the subclass of BallLarusNode* - // returned by createNode. - virtual BallLarusEdge* createEdge( - BallLarusNode* source, BallLarusNode* target, unsigned edgeNumber); - -private: - BLEdgeVector _treeEdges; // All edges in the spanning tree. - BLEdgeVector _chordEdges; // All edges not in the spanning tree. - GlobalVariable* _counterArray; // Array to store path counters - - // Removes the edge from the appropriate predecessor and successor lists. - void unlinkEdge(BallLarusEdge* edge); - - // Makes an edge part of the spanning tree. - void makeEdgeSpanning(BLInstrumentationEdge* edge); - - // Pushes initialization and calls itself recursively. - void pushInitializationFromEdge(BLInstrumentationEdge* edge); - - // Pushes path counter increments up recursively. - void pushCountersFromEdge(BLInstrumentationEdge* edge); - - // Depth first algorithm for determining the chord increments.f - void calculateChordIncrementsDfs( - long weight, BallLarusNode* v, BallLarusEdge* e); - - // Determines the relative direction of two edges. - int calculateChordIncrementsDir(BallLarusEdge* e, BallLarusEdge* f); -}; - -// --------------------------------------------------------------------------- -// PathProfiler is a module pass which instruments path profiling instructions -// --------------------------------------------------------------------------- -class PathProfiler : public ModulePass { -private: - // Current context for multi threading support. - LLVMContext* Context; - - // Which function are we currently instrumenting - unsigned currentFunctionNumber; - - // The function prototype in the profiling runtime for incrementing a - // single path counter in a hash table. - Constant* llvmIncrementHashFunction; - Constant* llvmDecrementHashFunction; - - // Instruments each function with path profiling. 'main' is instrumented - // with code to save the profile to disk. - bool runOnModule(Module &M); - - // Analyzes the function for Ball-Larus path profiling, and inserts code. - void runOnFunction(std::vector<Constant*> &ftInit, Function &F, Module &M); - - // Creates an increment constant representing incr. - ConstantInt* createIncrementConstant(long incr, int bitsize); - - // Creates an increment constant representing the value in - // edge->getIncrement(). - ConstantInt* createIncrementConstant(BLInstrumentationEdge* edge); - - // Finds the insertion point after pathNumber in block. PathNumber may - // be NULL. - BasicBlock::iterator getInsertionPoint( - BasicBlock* block, Value* pathNumber); - - // Inserts source's pathNumber Value* into target. Target may or may not - // have multiple predecessors, and may or may not have its phiNode - // initalized. - void pushValueIntoNode( - BLInstrumentationNode* source, BLInstrumentationNode* target); - - // Inserts source's pathNumber Value* into the appropriate slot of - // target's phiNode. - void pushValueIntoPHI( - BLInstrumentationNode* target, BLInstrumentationNode* source); - - // The Value* in node, oldVal, is updated with a Value* correspodning to - // oldVal + addition. - void insertNumberIncrement(BLInstrumentationNode* node, Value* addition, - bool atBeginning); - - // Creates a counter increment in the given node. The Value* in node is - // taken as the index into a hash table. - void insertCounterIncrement( - Value* incValue, - BasicBlock::iterator insertPoint, - BLInstrumentationDag* dag, - bool increment = true); - - // A PHINode is created in the node, and its values initialized to -1U. - void preparePHI(BLInstrumentationNode* node); - - // Inserts instrumentation for the given edge - // - // Pre: The edge's source node has pathNumber set if edge is non zero - // path number increment. - // - // Post: Edge's target node has a pathNumber set to the path number Value - // corresponding to the value of the path register after edge's - // execution. - void insertInstrumentationStartingAt( - BLInstrumentationEdge* edge, - BLInstrumentationDag* dag); - - // If this edge is a critical edge, then inserts a node at this edge. - // This edge becomes the first edge, and a new BallLarusEdge is created. - bool splitCritical(BLInstrumentationEdge* edge, BLInstrumentationDag* dag); - - // Inserts instrumentation according to the marked edges in dag. Phony - // edges must be unlinked from the DAG, but accessible from the - // backedges. Dag must have initializations, path number increments, and - // counter increments present. - // - // Counter storage is created here. - void insertInstrumentation( BLInstrumentationDag& dag, Module &M); - -public: - static char ID; // Pass identification, replacement for typeid - PathProfiler() : ModulePass(ID) { - initializePathProfilerPass(*PassRegistry::getPassRegistry()); - } - - virtual const char *getPassName() const { - return "Path Profiler"; - } -}; -} // end anonymous namespace - -// Should we print the dot-graphs -static cl::opt<bool> DotPathDag("path-profile-pathdag", cl::Hidden, - cl::desc("Output the path profiling DAG for each function.")); - -// Register the path profiler as a pass -char PathProfiler::ID = 0; -INITIALIZE_PASS(PathProfiler, "insert-path-profiling", - "Insert instrumentation for Ball-Larus path profiling", - false, false) - -ModulePass *llvm::createPathProfilerPass() { return new PathProfiler(); } - -namespace llvm { - class PathProfilingFunctionTable {}; - - // Type for global array storing references to hashes or arrays - template<bool xcompile> class TypeBuilder<PathProfilingFunctionTable, - xcompile> { - public: - static StructType *get(LLVMContext& C) { - return( StructType::get( - TypeBuilder<types::i<32>, xcompile>::get(C), // type - TypeBuilder<types::i<32>, xcompile>::get(C), // array size - TypeBuilder<types::i<8>*, xcompile>::get(C), // array/hash ptr - NULL)); - } - }; - - typedef TypeBuilder<PathProfilingFunctionTable, true> - ftEntryTypeBuilder; - - // BallLarusEdge << operator overloading - raw_ostream& operator<<(raw_ostream& os, - const BLInstrumentationEdge& edge) - LLVM_ATTRIBUTE_USED; - raw_ostream& operator<<(raw_ostream& os, - const BLInstrumentationEdge& edge) { - os << "[" << edge.getSource()->getName() << " -> " - << edge.getTarget()->getName() << "] init: " - << (edge.isInitialization() ? "yes" : "no") - << " incr:" << edge.getIncrement() << " cinc: " - << (edge.isCounterIncrement() ? "yes" : "no"); - return(os); - } -} - -// Creates a new BLInstrumentationNode from a BasicBlock. -BLInstrumentationNode::BLInstrumentationNode(BasicBlock* BB) : - BallLarusNode(BB), - _startingPathNumber(NULL), _endingPathNumber(NULL), _pathPHI(NULL) {} - -// Constructor for BLInstrumentationEdge. -BLInstrumentationEdge::BLInstrumentationEdge(BLInstrumentationNode* source, - BLInstrumentationNode* target) - : BallLarusEdge(source, target, 0), - _increment(0), _isInSpanningTree(false), _isInitialization(false), - _isCounterIncrement(false), _hasInstrumentation(false) {} - -// Sets the target node of this edge. Required to split edges. -void BLInstrumentationEdge::setTarget(BallLarusNode* node) { - _target = node; -} - -// Returns whether this edge is in the spanning tree. -bool BLInstrumentationEdge::isInSpanningTree() const { - return(_isInSpanningTree); -} - -// Sets whether this edge is in the spanning tree. -void BLInstrumentationEdge::setIsInSpanningTree(bool isInSpanningTree) { - _isInSpanningTree = isInSpanningTree; -} - -// Returns whether this edge will be instrumented with a path number -// initialization. -bool BLInstrumentationEdge::isInitialization() const { - return(_isInitialization); -} - -// Sets whether this edge will be instrumented with a path number -// initialization. -void BLInstrumentationEdge::setIsInitialization(bool isInitialization) { - _isInitialization = isInitialization; -} - -// Returns whether this edge will be instrumented with a path counter -// increment. Notice this is incrementing the path counter -// corresponding to the path number register. The path number -// increment is determined by getIncrement(). -bool BLInstrumentationEdge::isCounterIncrement() const { - return(_isCounterIncrement); -} - -// Sets whether this edge will be instrumented with a path counter -// increment. -void BLInstrumentationEdge::setIsCounterIncrement(bool isCounterIncrement) { - _isCounterIncrement = isCounterIncrement; -} - -// Gets the path number increment that this edge will be instrumented -// with. This is distinct from the path counter increment and the -// weight. The counter increment is counts the number of executions of -// some path, whereas the path number keeps track of which path number -// the program is on. -long BLInstrumentationEdge::getIncrement() const { - return(_increment); -} - -// Set whether this edge will be instrumented with a path number -// increment. -void BLInstrumentationEdge::setIncrement(long increment) { - _increment = increment; -} - -// True iff the edge has already been instrumented. -bool BLInstrumentationEdge::hasInstrumentation() { - return(_hasInstrumentation); -} - -// Set whether this edge has been instrumented. -void BLInstrumentationEdge::setHasInstrumentation(bool hasInstrumentation) { - _hasInstrumentation = hasInstrumentation; -} - -// Returns the successor number of this edge in the source. -unsigned BLInstrumentationEdge::getSuccessorNumber() { - BallLarusNode* sourceNode = getSource(); - BallLarusNode* targetNode = getTarget(); - BasicBlock* source = sourceNode->getBlock(); - BasicBlock* target = targetNode->getBlock(); - - if(source == NULL || target == NULL) - return(0); - - TerminatorInst* terminator = source->getTerminator(); - - unsigned i; - for(i=0; i < terminator->getNumSuccessors(); i++) { - if(terminator->getSuccessor(i) == target) - break; - } - - return(i); -} - -// BLInstrumentationDag constructor initializes a DAG for the given Function. -BLInstrumentationDag::BLInstrumentationDag(Function &F) : BallLarusDag(F), - _counterArray(0) { -} - -// Returns the Exit->Root edge. This edge is required for creating -// directed cycles in the algorithm for moving instrumentation off of -// the spanning tree -BallLarusEdge* BLInstrumentationDag::getExitRootEdge() { - BLEdgeIterator erEdge = getExit()->succBegin(); - return(*erEdge); -} - -BLEdgeVector BLInstrumentationDag::getCallPhonyEdges () { - BLEdgeVector callEdges; - - for( BLEdgeIterator edge = _edges.begin(), end = _edges.end(); - edge != end; edge++ ) { - if( (*edge)->getType() == BallLarusEdge::CALLEDGE_PHONY ) - callEdges.push_back(*edge); - } - - return callEdges; -} - -// Gets the path counter array -GlobalVariable* BLInstrumentationDag::getCounterArray() { - return _counterArray; -} - -void BLInstrumentationDag::setCounterArray(GlobalVariable* c) { - _counterArray = c; -} - -// Calculates the increment for the chords, thereby removing -// instrumentation from the spanning tree edges. Implementation is based on -// the algorithm in Figure 4 of [Ball94] -void BLInstrumentationDag::calculateChordIncrements() { - calculateChordIncrementsDfs(0, getRoot(), NULL); - - BLInstrumentationEdge* chord; - for(BLEdgeIterator chordEdge = _chordEdges.begin(), - end = _chordEdges.end(); chordEdge != end; chordEdge++) { - chord = (BLInstrumentationEdge*) *chordEdge; - chord->setIncrement(chord->getIncrement() + chord->getWeight()); - } -} - -// Updates the state when an edge has been split -void BLInstrumentationDag::splitUpdate(BLInstrumentationEdge* formerEdge, - BasicBlock* newBlock) { - BallLarusNode* oldTarget = formerEdge->getTarget(); - BallLarusNode* newNode = addNode(newBlock); - formerEdge->setTarget(newNode); - newNode->addPredEdge(formerEdge); - - DEBUG(dbgs() << " Edge split: " << *formerEdge << "\n"); - - oldTarget->removePredEdge(formerEdge); - BallLarusEdge* newEdge = addEdge(newNode, oldTarget,0); - - if( formerEdge->getType() == BallLarusEdge::BACKEDGE || - formerEdge->getType() == BallLarusEdge::SPLITEDGE) { - newEdge->setType(formerEdge->getType()); - newEdge->setPhonyRoot(formerEdge->getPhonyRoot()); - newEdge->setPhonyExit(formerEdge->getPhonyExit()); - formerEdge->setType(BallLarusEdge::NORMAL); - formerEdge->setPhonyRoot(NULL); - formerEdge->setPhonyExit(NULL); - } -} - -// Calculates a spanning tree of the DAG ignoring cycles. Whichever -// edges are in the spanning tree will not be instrumented, but this -// implementation does not try to minimize the instrumentation overhead -// by trying to find hot edges. -void BLInstrumentationDag::calculateSpanningTree() { - std::stack<BallLarusNode*> dfsStack; - - for(BLNodeIterator nodeIt = _nodes.begin(), end = _nodes.end(); - nodeIt != end; nodeIt++) { - (*nodeIt)->setColor(BallLarusNode::WHITE); - } - - dfsStack.push(getRoot()); - while(dfsStack.size() > 0) { - BallLarusNode* node = dfsStack.top(); - dfsStack.pop(); - - if(node->getColor() == BallLarusNode::WHITE) - continue; - - BallLarusNode* nextNode; - bool forward = true; - BLEdgeIterator succEnd = node->succEnd(); - - node->setColor(BallLarusNode::WHITE); - // first iterate over successors then predecessors - for(BLEdgeIterator edge = node->succBegin(), predEnd = node->predEnd(); - edge != predEnd; edge++) { - if(edge == succEnd) { - edge = node->predBegin(); - forward = false; - } - - // Ignore split edges - if ((*edge)->getType() == BallLarusEdge::SPLITEDGE) - continue; - - nextNode = forward? (*edge)->getTarget(): (*edge)->getSource(); - if(nextNode->getColor() != BallLarusNode::WHITE) { - nextNode->setColor(BallLarusNode::WHITE); - makeEdgeSpanning((BLInstrumentationEdge*)(*edge)); - } - } - } - - for(BLEdgeIterator edge = _edges.begin(), end = _edges.end(); - edge != end; edge++) { - BLInstrumentationEdge* instEdge = (BLInstrumentationEdge*) (*edge); - // safe since createEdge is overriden - if(!instEdge->isInSpanningTree() && (*edge)->getType() - != BallLarusEdge::SPLITEDGE) - _chordEdges.push_back(instEdge); - } -} - -// Pushes initialization further down in order to group the first -// increment and initialization. -void BLInstrumentationDag::pushInitialization() { - BLInstrumentationEdge* exitRootEdge = - (BLInstrumentationEdge*) getExitRootEdge(); - exitRootEdge->setIsInitialization(true); - pushInitializationFromEdge(exitRootEdge); -} - -// Pushes the path counter increments up in order to group the last path -// number increment. -void BLInstrumentationDag::pushCounters() { - BLInstrumentationEdge* exitRootEdge = - (BLInstrumentationEdge*) getExitRootEdge(); - exitRootEdge->setIsCounterIncrement(true); - pushCountersFromEdge(exitRootEdge); -} - -// Removes phony edges from the successor list of the source, and the -// predecessor list of the target. -void BLInstrumentationDag::unlinkPhony() { - BallLarusEdge* edge; - - for(BLEdgeIterator next = _edges.begin(), - end = _edges.end(); next != end; next++) { - edge = (*next); - - if( edge->getType() == BallLarusEdge::BACKEDGE_PHONY || - edge->getType() == BallLarusEdge::SPLITEDGE_PHONY || - edge->getType() == BallLarusEdge::CALLEDGE_PHONY ) { - unlinkEdge(edge); - } - } -} - -// Generate a .dot graph to represent the DAG and pathNumbers -void BLInstrumentationDag::generateDotGraph() { - std::string errorInfo; - std::string functionName = getFunction().getName().str(); - std::string filename = "pathdag." + functionName + ".dot"; - - DEBUG (dbgs() << "Writing '" << filename << "'...\n"); - raw_fd_ostream dotFile(filename.c_str(), errorInfo); - - if (!errorInfo.empty()) { - errs() << "Error opening '" << filename.c_str() <<"' for writing!"; - errs() << "\n"; - return; - } - - dotFile << "digraph " << functionName << " {\n"; - - for( BLEdgeIterator edge = _edges.begin(), end = _edges.end(); - edge != end; edge++) { - std::string sourceName = (*edge)->getSource()->getName(); - std::string targetName = (*edge)->getTarget()->getName(); - - dotFile << "\t\"" << sourceName.c_str() << "\" -> \"" - << targetName.c_str() << "\" "; - - long inc = ((BLInstrumentationEdge*)(*edge))->getIncrement(); - - switch( (*edge)->getType() ) { - case BallLarusEdge::NORMAL: - dotFile << "[label=" << inc << "] [color=black];\n"; - break; - - case BallLarusEdge::BACKEDGE: - dotFile << "[color=cyan];\n"; - break; - - case BallLarusEdge::BACKEDGE_PHONY: - dotFile << "[label=" << inc - << "] [color=blue];\n"; - break; - - case BallLarusEdge::SPLITEDGE: - dotFile << "[color=violet];\n"; - break; - - case BallLarusEdge::SPLITEDGE_PHONY: - dotFile << "[label=" << inc << "] [color=red];\n"; - break; - - case BallLarusEdge::CALLEDGE_PHONY: - dotFile << "[label=" << inc << "] [color=green];\n"; - break; - } - } - - dotFile << "}\n"; -} - -// Allows subclasses to determine which type of Node is created. -// Override this method to produce subclasses of BallLarusNode if -// necessary. The destructor of BallLarusDag will call free on each pointer -// created. -BallLarusNode* BLInstrumentationDag::createNode(BasicBlock* BB) { - return( new BLInstrumentationNode(BB) ); -} - -// Allows subclasses to determine which type of Edge is created. -// Override this method to produce subclasses of BallLarusEdge if -// necessary. The destructor of BallLarusDag will call free on each pointer -// created. -BallLarusEdge* BLInstrumentationDag::createEdge(BallLarusNode* source, - BallLarusNode* target, unsigned edgeNumber) { - // One can cast from BallLarusNode to BLInstrumentationNode since createNode - // is overriden to produce BLInstrumentationNode. - return( new BLInstrumentationEdge((BLInstrumentationNode*)source, - (BLInstrumentationNode*)target) ); -} - -// Sets the Value corresponding to the pathNumber register, constant, -// or phinode. Used by the instrumentation code to remember path -// number Values. -Value* BLInstrumentationNode::getStartingPathNumber(){ - return(_startingPathNumber); -} - -// Sets the Value of the pathNumber. Used by the instrumentation code. -void BLInstrumentationNode::setStartingPathNumber(Value* pathNumber) { - DEBUG(dbgs() << " SPN-" << getName() << " <-- " << (pathNumber ? - pathNumber->getName() : - "unused") << "\n"); - _startingPathNumber = pathNumber; -} - -Value* BLInstrumentationNode::getEndingPathNumber(){ - return(_endingPathNumber); -} - -void BLInstrumentationNode::setEndingPathNumber(Value* pathNumber) { - DEBUG(dbgs() << " EPN-" << getName() << " <-- " - << (pathNumber ? pathNumber->getName() : "unused") << "\n"); - _endingPathNumber = pathNumber; -} - -// Get the PHINode Instruction for this node. Used by instrumentation -// code. -PHINode* BLInstrumentationNode::getPathPHI() { - return(_pathPHI); -} - -// Set the PHINode Instruction for this node. Used by instrumentation -// code. -void BLInstrumentationNode::setPathPHI(PHINode* pathPHI) { - _pathPHI = pathPHI; -} - -// Removes the edge from the appropriate predecessor and successor -// lists. -void BLInstrumentationDag::unlinkEdge(BallLarusEdge* edge) { - if(edge == getExitRootEdge()) - DEBUG(dbgs() << " Removing exit->root edge\n"); - - edge->getSource()->removeSuccEdge(edge); - edge->getTarget()->removePredEdge(edge); -} - -// Makes an edge part of the spanning tree. -void BLInstrumentationDag::makeEdgeSpanning(BLInstrumentationEdge* edge) { - edge->setIsInSpanningTree(true); - _treeEdges.push_back(edge); -} - -// Pushes initialization and calls itself recursively. -void BLInstrumentationDag::pushInitializationFromEdge( - BLInstrumentationEdge* edge) { - BallLarusNode* target; - - target = edge->getTarget(); - if( target->getNumberPredEdges() > 1 || target == getExit() ) { - return; - } else { - for(BLEdgeIterator next = target->succBegin(), - end = target->succEnd(); next != end; next++) { - BLInstrumentationEdge* intoEdge = (BLInstrumentationEdge*) *next; - - // Skip split edges - if (intoEdge->getType() == BallLarusEdge::SPLITEDGE) - continue; - - intoEdge->setIncrement(intoEdge->getIncrement() + - edge->getIncrement()); - intoEdge->setIsInitialization(true); - pushInitializationFromEdge(intoEdge); - } - - edge->setIncrement(0); - edge->setIsInitialization(false); - } -} - -// Pushes path counter increments up recursively. -void BLInstrumentationDag::pushCountersFromEdge(BLInstrumentationEdge* edge) { - BallLarusNode* source; - - source = edge->getSource(); - if(source->getNumberSuccEdges() > 1 || source == getRoot() - || edge->isInitialization()) { - return; - } else { - for(BLEdgeIterator previous = source->predBegin(), - end = source->predEnd(); previous != end; previous++) { - BLInstrumentationEdge* fromEdge = (BLInstrumentationEdge*) *previous; - - // Skip split edges - if (fromEdge->getType() == BallLarusEdge::SPLITEDGE) - continue; - - fromEdge->setIncrement(fromEdge->getIncrement() + - edge->getIncrement()); - fromEdge->setIsCounterIncrement(true); - pushCountersFromEdge(fromEdge); - } - - edge->setIncrement(0); - edge->setIsCounterIncrement(false); - } -} - -// Depth first algorithm for determining the chord increments. -void BLInstrumentationDag::calculateChordIncrementsDfs(long weight, - BallLarusNode* v, BallLarusEdge* e) { - BLInstrumentationEdge* f; - - for(BLEdgeIterator treeEdge = _treeEdges.begin(), - end = _treeEdges.end(); treeEdge != end; treeEdge++) { - f = (BLInstrumentationEdge*) *treeEdge; - if(e != f && v == f->getTarget()) { - calculateChordIncrementsDfs( - calculateChordIncrementsDir(e,f)*(weight) + - f->getWeight(), f->getSource(), f); - } - if(e != f && v == f->getSource()) { - calculateChordIncrementsDfs( - calculateChordIncrementsDir(e,f)*(weight) + - f->getWeight(), f->getTarget(), f); - } - } - - for(BLEdgeIterator chordEdge = _chordEdges.begin(), - end = _chordEdges.end(); chordEdge != end; chordEdge++) { - f = (BLInstrumentationEdge*) *chordEdge; - if(v == f->getSource() || v == f->getTarget()) { - f->setIncrement(f->getIncrement() + - calculateChordIncrementsDir(e,f)*weight); - } - } -} - -// Determines the relative direction of two edges. -int BLInstrumentationDag::calculateChordIncrementsDir(BallLarusEdge* e, - BallLarusEdge* f) { - if( e == NULL) - return(1); - else if(e->getSource() == f->getTarget() - || e->getTarget() == f->getSource()) - return(1); - - return(-1); -} - -// Creates an increment constant representing incr. -ConstantInt* PathProfiler::createIncrementConstant(long incr, - int bitsize) { - return(ConstantInt::get(IntegerType::get(*Context, 32), incr)); -} - -// Creates an increment constant representing the value in -// edge->getIncrement(). -ConstantInt* PathProfiler::createIncrementConstant( - BLInstrumentationEdge* edge) { - return(createIncrementConstant(edge->getIncrement(), 32)); -} - -// Finds the insertion point after pathNumber in block. PathNumber may -// be NULL. -BasicBlock::iterator PathProfiler::getInsertionPoint(BasicBlock* block, Value* - pathNumber) { - if(pathNumber == NULL || isa<ConstantInt>(pathNumber) - || (((Instruction*)(pathNumber))->getParent()) != block) { - return(block->getFirstInsertionPt()); - } else { - Instruction* pathNumberInst = (Instruction*) (pathNumber); - BasicBlock::iterator insertPoint; - BasicBlock::iterator end = block->end(); - - for(insertPoint = block->begin(); - insertPoint != end; insertPoint++) { - Instruction* insertInst = &(*insertPoint); - - if(insertInst == pathNumberInst) - return(++insertPoint); - } - - return(insertPoint); - } -} - -// A PHINode is created in the node, and its values initialized to -1U. -void PathProfiler::preparePHI(BLInstrumentationNode* node) { - BasicBlock* block = node->getBlock(); - BasicBlock::iterator insertPoint = block->getFirstInsertionPt(); - pred_iterator PB = pred_begin(node->getBlock()), - PE = pred_end(node->getBlock()); - PHINode* phi = PHINode::Create(Type::getInt32Ty(*Context), - std::distance(PB, PE), "pathNumber", - insertPoint ); - node->setPathPHI(phi); - node->setStartingPathNumber(phi); - node->setEndingPathNumber(phi); - - for(pred_iterator predIt = PB; predIt != PE; predIt++) { - BasicBlock* pred = (*predIt); - - if(pred != NULL) - phi->addIncoming(createIncrementConstant((long)-1, 32), pred); - } -} - -// Inserts source's pathNumber Value* into target. Target may or may not -// have multiple predecessors, and may or may not have its phiNode -// initalized. -void PathProfiler::pushValueIntoNode(BLInstrumentationNode* source, - BLInstrumentationNode* target) { - if(target->getBlock() == NULL) - return; - - - if(target->getNumberPredEdges() <= 1) { - assert(target->getStartingPathNumber() == NULL && - "Target already has path number"); - target->setStartingPathNumber(source->getEndingPathNumber()); - target->setEndingPathNumber(source->getEndingPathNumber()); - DEBUG(dbgs() << " Passing path number" - << (source->getEndingPathNumber() ? "" : " (null)") - << " value through.\n"); - } else { - if(target->getPathPHI() == NULL) { - DEBUG(dbgs() << " Initializing PHI node for block '" - << target->getName() << "'\n"); - preparePHI(target); - } - pushValueIntoPHI(target, source); - DEBUG(dbgs() << " Passing number value into PHI for block '" - << target->getName() << "'\n"); - } -} - -// Inserts source's pathNumber Value* into the appropriate slot of -// target's phiNode. -void PathProfiler::pushValueIntoPHI(BLInstrumentationNode* target, - BLInstrumentationNode* source) { - PHINode* phi = target->getPathPHI(); - assert(phi != NULL && " Tried to push value into node with PHI, but node" - " actually had no PHI."); - phi->removeIncomingValue(source->getBlock(), false); - phi->addIncoming(source->getEndingPathNumber(), source->getBlock()); -} - -// The Value* in node, oldVal, is updated with a Value* correspodning to -// oldVal + addition. -void PathProfiler::insertNumberIncrement(BLInstrumentationNode* node, - Value* addition, bool atBeginning) { - BasicBlock* block = node->getBlock(); - assert(node->getStartingPathNumber() != NULL); - assert(node->getEndingPathNumber() != NULL); - - BasicBlock::iterator insertPoint; - - if( atBeginning ) - insertPoint = block->getFirstInsertionPt(); - else - insertPoint = block->getTerminator(); - - DEBUG(errs() << " Creating addition instruction.\n"); - Value* newpn = BinaryOperator::Create(Instruction::Add, - node->getStartingPathNumber(), - addition, "pathNumber", insertPoint); - - node->setEndingPathNumber(newpn); - - if( atBeginning ) - node->setStartingPathNumber(newpn); -} - -// Creates a counter increment in the given node. The Value* in node is -// taken as the index into an array or hash table. The hash table access -// is a call to the runtime. -void PathProfiler::insertCounterIncrement(Value* incValue, - BasicBlock::iterator insertPoint, - BLInstrumentationDag* dag, - bool increment) { - // Counter increment for array - if( dag->getNumberOfPaths() <= HASH_THRESHHOLD ) { - // Get pointer to the array location - std::vector<Value*> gepIndices(2); - gepIndices[0] = Constant::getNullValue(Type::getInt32Ty(*Context)); - gepIndices[1] = incValue; - - GetElementPtrInst* pcPointer = - GetElementPtrInst::Create(dag->getCounterArray(), gepIndices, - "counterInc", insertPoint); - - // Load from the array - call it oldPC - LoadInst* oldPc = new LoadInst(pcPointer, "oldPC", insertPoint); - - // Test to see whether adding 1 will overflow the counter - ICmpInst* isMax = new ICmpInst(insertPoint, CmpInst::ICMP_ULT, oldPc, - createIncrementConstant(0xffffffff, 32), - "isMax"); - - // Select increment for the path counter based on overflow - SelectInst* inc = - SelectInst::Create( isMax, createIncrementConstant(increment?1:-1,32), - createIncrementConstant(0,32), - "pathInc", insertPoint); - - // newPc = oldPc + inc - BinaryOperator* newPc = BinaryOperator::Create(Instruction::Add, - oldPc, inc, "newPC", - insertPoint); - - // Store back in to the array - new StoreInst(newPc, pcPointer, insertPoint); - } else { // Counter increment for hash - std::vector<Value*> args(2); - args[0] = ConstantInt::get(Type::getInt32Ty(*Context), - currentFunctionNumber); - args[1] = incValue; - - CallInst::Create( - increment ? llvmIncrementHashFunction : llvmDecrementHashFunction, - args, "", insertPoint); - } -} - -// Inserts instrumentation for the given edge -// -// Pre: The edge's source node has pathNumber set if edge is non zero -// path number increment. -// -// Post: Edge's target node has a pathNumber set to the path number Value -// corresponding to the value of the path register after edge's -// execution. -// -// FIXME: This should be reworked so it's not recursive. -void PathProfiler::insertInstrumentationStartingAt(BLInstrumentationEdge* edge, - BLInstrumentationDag* dag) { - // Mark the edge as instrumented - edge->setHasInstrumentation(true); - DEBUG(dbgs() << "\nInstrumenting edge: " << (*edge) << "\n"); - - // create a new node for this edge's instrumentation - splitCritical(edge, dag); - - BLInstrumentationNode* sourceNode = (BLInstrumentationNode*)edge->getSource(); - BLInstrumentationNode* targetNode = (BLInstrumentationNode*)edge->getTarget(); - BLInstrumentationNode* instrumentNode; - BLInstrumentationNode* nextSourceNode; - - bool atBeginning = false; - - // Source node has only 1 successor so any information can be simply - // inserted in to it without splitting - if( sourceNode->getBlock() && sourceNode->getNumberSuccEdges() <= 1) { - DEBUG(dbgs() << " Potential instructions to be placed in: " - << sourceNode->getName() << " (at end)\n"); - instrumentNode = sourceNode; - nextSourceNode = targetNode; // ... since we never made any new nodes - } - - // The target node only has one predecessor, so we can safely insert edge - // instrumentation into it. If there was splitting, it must have been - // successful. - else if( targetNode->getNumberPredEdges() == 1 ) { - DEBUG(dbgs() << " Potential instructions to be placed in: " - << targetNode->getName() << " (at beginning)\n"); - pushValueIntoNode(sourceNode, targetNode); - instrumentNode = targetNode; - nextSourceNode = NULL; // ... otherwise we'll just keep splitting - atBeginning = true; - } - - // Somehow, splitting must have failed. - else { - errs() << "Instrumenting could not split a critical edge.\n"; - DEBUG(dbgs() << " Couldn't split edge " << (*edge) << ".\n"); - return; - } - - // Insert instrumentation if this is a back or split edge - if( edge->getType() == BallLarusEdge::BACKEDGE || - edge->getType() == BallLarusEdge::SPLITEDGE ) { - BLInstrumentationEdge* top = - (BLInstrumentationEdge*) edge->getPhonyRoot(); - BLInstrumentationEdge* bottom = - (BLInstrumentationEdge*) edge->getPhonyExit(); - - assert( top->isInitialization() && " Top phony edge did not" - " contain a path number initialization."); - assert( bottom->isCounterIncrement() && " Bottom phony edge" - " did not contain a path counter increment."); - - // split edge has yet to be initialized - if( !instrumentNode->getEndingPathNumber() ) { - instrumentNode->setStartingPathNumber(createIncrementConstant(0,32)); - instrumentNode->setEndingPathNumber(createIncrementConstant(0,32)); - } - - BasicBlock::iterator insertPoint = atBeginning ? - instrumentNode->getBlock()->getFirstInsertionPt() : - instrumentNode->getBlock()->getTerminator(); - - // add information from the bottom edge, if it exists - if( bottom->getIncrement() ) { - Value* newpn = - BinaryOperator::Create(Instruction::Add, - instrumentNode->getStartingPathNumber(), - createIncrementConstant(bottom), - "pathNumber", insertPoint); - instrumentNode->setEndingPathNumber(newpn); - } - - insertCounterIncrement(instrumentNode->getEndingPathNumber(), - insertPoint, dag); - - if( atBeginning ) - instrumentNode->setStartingPathNumber(createIncrementConstant(top)); - - instrumentNode->setEndingPathNumber(createIncrementConstant(top)); - - // Check for path counter increments - if( top->isCounterIncrement() ) { - insertCounterIncrement(instrumentNode->getEndingPathNumber(), - instrumentNode->getBlock()->getTerminator(),dag); - instrumentNode->setEndingPathNumber(0); - } - } - - // Insert instrumentation if this is a normal edge - else { - BasicBlock::iterator insertPoint = atBeginning ? - instrumentNode->getBlock()->getFirstInsertionPt() : - instrumentNode->getBlock()->getTerminator(); - - if( edge->isInitialization() ) { // initialize path number - instrumentNode->setEndingPathNumber(createIncrementConstant(edge)); - } else if( edge->getIncrement() ) {// increment path number - Value* newpn = - BinaryOperator::Create(Instruction::Add, - instrumentNode->getStartingPathNumber(), - createIncrementConstant(edge), - "pathNumber", insertPoint); - instrumentNode->setEndingPathNumber(newpn); - - if( atBeginning ) - instrumentNode->setStartingPathNumber(newpn); - } - - // Check for path counter increments - if( edge->isCounterIncrement() ) { - insertCounterIncrement(instrumentNode->getEndingPathNumber(), - insertPoint, dag); - instrumentNode->setEndingPathNumber(0); - } - } - - // Push it along - if (nextSourceNode && instrumentNode->getEndingPathNumber()) - pushValueIntoNode(instrumentNode, nextSourceNode); - - // Add all the successors - for( BLEdgeIterator next = targetNode->succBegin(), - end = targetNode->succEnd(); next != end; next++ ) { - // So long as it is un-instrumented, add it to the list - if( !((BLInstrumentationEdge*)(*next))->hasInstrumentation() ) - insertInstrumentationStartingAt((BLInstrumentationEdge*)*next,dag); - else - DEBUG(dbgs() << " Edge " << *(BLInstrumentationEdge*)(*next) - << " already instrumented.\n"); - } -} - -// Inserts instrumentation according to the marked edges in dag. Phony edges -// must be unlinked from the DAG, but accessible from the backedges. Dag -// must have initializations, path number increments, and counter increments -// present. -// -// Counter storage is created here. -void PathProfiler::insertInstrumentation( - BLInstrumentationDag& dag, Module &M) { - - BLInstrumentationEdge* exitRootEdge = - (BLInstrumentationEdge*) dag.getExitRootEdge(); - insertInstrumentationStartingAt(exitRootEdge, &dag); - - // Iterate through each call edge and apply the appropriate hash increment - // and decrement functions - BLEdgeVector callEdges = dag.getCallPhonyEdges(); - for( BLEdgeIterator edge = callEdges.begin(), - end = callEdges.end(); edge != end; edge++ ) { - BLInstrumentationNode* node = - (BLInstrumentationNode*)(*edge)->getSource(); - BasicBlock::iterator insertPoint = node->getBlock()->getFirstInsertionPt(); - - // Find the first function call - while( ((Instruction&)(*insertPoint)).getOpcode() != Instruction::Call ) - insertPoint++; - - DEBUG(dbgs() << "\nInstrumenting method call block '" - << node->getBlock()->getName() << "'\n"); - DEBUG(dbgs() << " Path number initialized: " - << ((node->getStartingPathNumber()) ? "yes" : "no") << "\n"); - - Value* newpn; - if( node->getStartingPathNumber() ) { - long inc = ((BLInstrumentationEdge*)(*edge))->getIncrement(); - if ( inc ) - newpn = BinaryOperator::Create(Instruction::Add, - node->getStartingPathNumber(), - createIncrementConstant(inc,32), - "pathNumber", insertPoint); - else - newpn = node->getStartingPathNumber(); - } else { - newpn = (Value*)createIncrementConstant( - ((BLInstrumentationEdge*)(*edge))->getIncrement(), 32); - } - - insertCounterIncrement(newpn, insertPoint, &dag); - insertCounterIncrement(newpn, node->getBlock()->getTerminator(), - &dag, false); - } -} - -// Entry point of the module -void PathProfiler::runOnFunction(std::vector<Constant*> &ftInit, - Function &F, Module &M) { - // Build DAG from CFG - BLInstrumentationDag dag = BLInstrumentationDag(F); - dag.init(); - - // give each path a unique integer value - dag.calculatePathNumbers(); - - // modify path increments to increase the efficiency - // of instrumentation - dag.calculateSpanningTree(); - dag.calculateChordIncrements(); - dag.pushInitialization(); - dag.pushCounters(); - dag.unlinkPhony(); - - // potentially generate .dot graph for the dag - if (DotPathDag) - dag.generateDotGraph (); - - // Should we store the information in an array or hash - if( dag.getNumberOfPaths() <= HASH_THRESHHOLD ) { - Type* t = ArrayType::get(Type::getInt32Ty(*Context), - dag.getNumberOfPaths()); - - dag.setCounterArray(new GlobalVariable(M, t, false, - GlobalValue::InternalLinkage, - Constant::getNullValue(t), "")); - } - - insertInstrumentation(dag, M); - - // Add to global function reference table - unsigned type; - Type* voidPtr = TypeBuilder<types::i<8>*, true>::get(*Context); - - if( dag.getNumberOfPaths() <= HASH_THRESHHOLD ) - type = ProfilingArray; - else - type = ProfilingHash; - - std::vector<Constant*> entryArray(3); - entryArray[0] = createIncrementConstant(type,32); - entryArray[1] = createIncrementConstant(dag.getNumberOfPaths(),32); - entryArray[2] = dag.getCounterArray() ? - ConstantExpr::getBitCast(dag.getCounterArray(), voidPtr) : - Constant::getNullValue(voidPtr); - - StructType* at = ftEntryTypeBuilder::get(*Context); - ConstantStruct* functionEntry = - (ConstantStruct*)ConstantStruct::get(at, entryArray); - ftInit.push_back(functionEntry); -} - -// Output the bitcode if we want to observe instrumentation changess -#define PRINT_MODULE dbgs() << \ - "\n\n============= MODULE BEGIN ===============\n" << M << \ - "\n============== MODULE END ================\n" - -bool PathProfiler::runOnModule(Module &M) { - Context = &M.getContext(); - - DEBUG(dbgs() - << "****************************************\n" - << "****************************************\n" - << "** **\n" - << "** PATH PROFILING INSTRUMENTATION **\n" - << "** **\n" - << "****************************************\n" - << "****************************************\n"); - - // No main, no instrumentation! - Function *Main = M.getFunction("main"); - - // Using fortran? ... this kind of works - if (!Main) - Main = M.getFunction("MAIN__"); - - if (!Main) { - errs() << "WARNING: cannot insert path profiling into a module" - << " with no main function!\n"; - return false; - } - - llvmIncrementHashFunction = M.getOrInsertFunction( - "llvm_increment_path_count", - Type::getVoidTy(*Context), // return type - Type::getInt32Ty(*Context), // function number - Type::getInt32Ty(*Context), // path number - NULL ); - - llvmDecrementHashFunction = M.getOrInsertFunction( - "llvm_decrement_path_count", - Type::getVoidTy(*Context), // return type - Type::getInt32Ty(*Context), // function number - Type::getInt32Ty(*Context), // path number - NULL ); - - std::vector<Constant*> ftInit; - unsigned functionNumber = 0; - for (Module::iterator F = M.begin(), E = M.end(); F != E; F++) { - if (F->isDeclaration()) - continue; - - DEBUG(dbgs() << "Function: " << F->getName() << "\n"); - functionNumber++; - - // set function number - currentFunctionNumber = functionNumber; - runOnFunction(ftInit, *F, M); - } - - Type *t = ftEntryTypeBuilder::get(*Context); - ArrayType* ftArrayType = ArrayType::get(t, ftInit.size()); - Constant* ftInitConstant = ConstantArray::get(ftArrayType, ftInit); - - DEBUG(dbgs() << " ftArrayType:" << *ftArrayType << "\n"); - - GlobalVariable* functionTable = - new GlobalVariable(M, ftArrayType, false, GlobalValue::InternalLinkage, - ftInitConstant, "functionPathTable"); - Type *eltType = ftArrayType->getTypeAtIndex((unsigned)0); - InsertProfilingInitCall(Main, "llvm_start_path_profiling", functionTable, - PointerType::getUnqual(eltType)); - - DEBUG(PRINT_MODULE); - - return true; -} - -// If this edge is a critical edge, then inserts a node at this edge. -// This edge becomes the first edge, and a new BallLarusEdge is created. -// Returns true if the edge was split -bool PathProfiler::splitCritical(BLInstrumentationEdge* edge, - BLInstrumentationDag* dag) { - unsigned succNum = edge->getSuccessorNumber(); - BallLarusNode* sourceNode = edge->getSource(); - BallLarusNode* targetNode = edge->getTarget(); - BasicBlock* sourceBlock = sourceNode->getBlock(); - BasicBlock* targetBlock = targetNode->getBlock(); - - if(sourceBlock == NULL || targetBlock == NULL - || sourceNode->getNumberSuccEdges() <= 1 - || targetNode->getNumberPredEdges() == 1 ) { - return(false); - } - - TerminatorInst* terminator = sourceBlock->getTerminator(); - - if( SplitCriticalEdge(terminator, succNum, this, false)) { - BasicBlock* newBlock = terminator->getSuccessor(succNum); - dag->splitUpdate(edge, newBlock); - return(true); - } else - return(false); -} |
