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diff --git a/lib/Transforms/Instrumentation/EdgeProfiling.cpp b/lib/Transforms/Instrumentation/EdgeProfiling.cpp
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-//===- 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;
-}
-