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Diffstat (limited to 'lib/Transforms/Instrumentation/EdgeProfiling.cpp')
-rw-r--r-- | lib/Transforms/Instrumentation/EdgeProfiling.cpp | 117 |
1 files changed, 0 insertions, 117 deletions
diff --git a/lib/Transforms/Instrumentation/EdgeProfiling.cpp b/lib/Transforms/Instrumentation/EdgeProfiling.cpp deleted file mode 100644 index a2459fb..0000000 --- a/lib/Transforms/Instrumentation/EdgeProfiling.cpp +++ /dev/null @@ -1,117 +0,0 @@ -//===- EdgeProfiling.cpp - Insert counters for edge 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 the specified program with counters for edge profiling. -// Edge profiling can give a reasonable approximation of the hot paths through a -// program, and is used for a wide variety of program transformations. -// -// Note that this implementation is very naive. We insert a counter for *every* -// edge in the program, instead of using control flow information to prune the -// number of counters inserted. -// -//===----------------------------------------------------------------------===// -#define DEBUG_TYPE "insert-edge-profiling" - -#include "llvm/Transforms/Instrumentation.h" -#include "ProfilingUtils.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/IR/Module.h" -#include "llvm/Pass.h" -#include "llvm/Support/raw_ostream.h" -#include "llvm/Transforms/Utils/BasicBlockUtils.h" -#include <set> -using namespace llvm; - -STATISTIC(NumEdgesInserted, "The # of edges inserted."); - -namespace { - class EdgeProfiler : public ModulePass { - bool runOnModule(Module &M); - public: - static char ID; // Pass identification, replacement for typeid - EdgeProfiler() : ModulePass(ID) { - initializeEdgeProfilerPass(*PassRegistry::getPassRegistry()); - } - - virtual const char *getPassName() const { - return "Edge Profiler"; - } - }; -} - -char EdgeProfiler::ID = 0; -INITIALIZE_PASS(EdgeProfiler, "insert-edge-profiling", - "Insert instrumentation for edge profiling", false, false) - -ModulePass *llvm::createEdgeProfilerPass() { return new EdgeProfiler(); } - -bool EdgeProfiler::runOnModule(Module &M) { - Function *Main = M.getFunction("main"); - if (Main == 0) { - errs() << "WARNING: cannot insert edge profiling into a module" - << " with no main function!\n"; - return false; // No main, no instrumentation! - } - - std::set<BasicBlock*> BlocksToInstrument; - unsigned NumEdges = 0; - for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { - if (F->isDeclaration()) continue; - // Reserve space for (0,entry) edge. - ++NumEdges; - for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { - // Keep track of which blocks need to be instrumented. We don't want to - // instrument blocks that are added as the result of breaking critical - // edges! - BlocksToInstrument.insert(BB); - NumEdges += BB->getTerminator()->getNumSuccessors(); - } - } - - Type *ATy = ArrayType::get(Type::getInt32Ty(M.getContext()), NumEdges); - GlobalVariable *Counters = - new GlobalVariable(M, ATy, false, GlobalValue::InternalLinkage, - Constant::getNullValue(ATy), "EdgeProfCounters"); - NumEdgesInserted = NumEdges; - - // Instrument all of the edges... - unsigned i = 0; - for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { - if (F->isDeclaration()) continue; - // Create counter for (0,entry) edge. - IncrementCounterInBlock(&F->getEntryBlock(), i++, Counters); - for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) - if (BlocksToInstrument.count(BB)) { // Don't instrument inserted blocks - // Okay, we have to add a counter of each outgoing edge. If the - // outgoing edge is not critical don't split it, just insert the counter - // in the source or destination of the edge. - TerminatorInst *TI = BB->getTerminator(); - for (unsigned s = 0, e = TI->getNumSuccessors(); s != e; ++s) { - // If the edge is critical, split it. - SplitCriticalEdge(TI, s, this); - - // Okay, we are guaranteed that the edge is no longer critical. If we - // only have a single successor, insert the counter in this block, - // otherwise insert it in the successor block. - if (TI->getNumSuccessors() == 1) { - // Insert counter at the start of the block - IncrementCounterInBlock(BB, i++, Counters, false); - } else { - // Insert counter at the start of the block - IncrementCounterInBlock(TI->getSuccessor(s), i++, Counters); - } - } - } - } - - // Add the initialization call to main. - InsertProfilingInitCall(Main, "llvm_start_edge_profiling", Counters); - return true; -} - |