diff options
| -rw-r--r-- | include/llvm/Analysis/ProfileInfoTypes.h | 3 | ||||
| -rw-r--r-- | lib/Transforms/Instrumentation/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | lib/Transforms/Instrumentation/OptimalEdgeProfiling.cpp | 186 | ||||
| -rw-r--r-- | runtime/libprofile/OptimalEdgeProfiling.c | 45 | ||||
| -rw-r--r-- | runtime/libprofile/exported_symbols.lst | 1 |
5 files changed, 235 insertions, 1 deletions
diff --git a/include/llvm/Analysis/ProfileInfoTypes.h b/include/llvm/Analysis/ProfileInfoTypes.h index f311f8c..0d531d5 100644 --- a/include/llvm/Analysis/ProfileInfoTypes.h +++ b/include/llvm/Analysis/ProfileInfoTypes.h @@ -22,7 +22,8 @@ enum ProfilingType { BlockInfo = 3, /* Block profiling information */ EdgeInfo = 4, /* Edge profiling information */ PathInfo = 5, /* Path profiling information */ - BBTraceInfo = 6 /* Basic block trace information */ + BBTraceInfo = 6, /* Basic block trace information */ + OptEdgeInfo = 7 /* Edge profiling information, optimal version */ }; #endif /* LLVM_ANALYSIS_PROFILEINFOTYPES_H */ diff --git a/lib/Transforms/Instrumentation/CMakeLists.txt b/lib/Transforms/Instrumentation/CMakeLists.txt index 83e12e1..be6a451 100644 --- a/lib/Transforms/Instrumentation/CMakeLists.txt +++ b/lib/Transforms/Instrumentation/CMakeLists.txt @@ -2,6 +2,7 @@ add_llvm_library(LLVMInstrumentation BlockProfiling.cpp EdgeProfiling.cpp MaximumSpanningTree.cpp + OptimalEdgeProfiling.cpp ProfilingUtils.cpp RSProfiling.cpp ) diff --git a/lib/Transforms/Instrumentation/OptimalEdgeProfiling.cpp b/lib/Transforms/Instrumentation/OptimalEdgeProfiling.cpp new file mode 100644 index 0000000..b6b996d --- /dev/null +++ b/lib/Transforms/Instrumentation/OptimalEdgeProfiling.cpp @@ -0,0 +1,186 @@ +//===- OptimalEdgeProfiling.cpp - Insert counters for opt. 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. +// +//===----------------------------------------------------------------------===// +#define DEBUG_TYPE "insert-optimal-edge-profiling" +#include "ProfilingUtils.h" +#include "llvm/Constants.h" +#include "llvm/Function.h" +#include "llvm/LLVMContext.h" +#include "llvm/Module.h" +#include "llvm/Pass.h" +#include "llvm/Analysis/Passes.h" +#include "llvm/Analysis/ProfileInfo.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Debug.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" +#include "llvm/Transforms/Instrumentation.h" +#include "llvm/ADT/Statistic.h" +#include "MaximumSpanningTree.h" +#include <set> +using namespace llvm; + +STATISTIC(NumEdgesInserted, "The # of edges inserted."); + +namespace { + class VISIBILITY_HIDDEN OptimalEdgeProfiler : public ModulePass { + bool runOnModule(Module &M); + ProfileInfo *PI; + public: + static char ID; // Pass identification, replacement for typeid + OptimalEdgeProfiler() : ModulePass(&ID) {} + + void getAnalysisUsage(AnalysisUsage &AU) const { + AU.addRequiredID(ProfileEstimatorPassID); + AU.addRequired<ProfileInfo>(); + } + + virtual const char *getPassName() const { + return "Optimal Edge Profiler"; + } + }; +} + +char OptimalEdgeProfiler::ID = 0; +static RegisterPass<OptimalEdgeProfiler> +X("insert-optimal-edge-profiling", + "Insert optimal instrumentation for edge profiling"); + +ModulePass *llvm::createOptimalEdgeProfilerPass() { + return new OptimalEdgeProfiler(); +} + +inline static void printEdgeCounter(ProfileInfo::Edge e, + BasicBlock* b, + unsigned i) { + DEBUG(errs() << "--Edge Counter for " << (e) << " in " \ + << ((b)?(b)->getNameStr():"0") << " (# " << (i) << ")\n"); +} + +bool OptimalEdgeProfiler::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); + if (BB->getTerminator()->getNumSuccessors() == 0) { + // Reserve space for (BB,0) edge. + ++NumEdges; + } else { + NumEdges += BB->getTerminator()->getNumSuccessors(); + } + } + } + + const Type *Int32 = Type::getInt32Ty(M.getContext()); + const ArrayType *ATy = ArrayType::get(Int32, NumEdges); + GlobalVariable *Counters = + new GlobalVariable(M, ATy, false, GlobalValue::InternalLinkage, + Constant::getNullValue(ATy), "OptEdgeProfCounters"); + NumEdgesInserted = 0; + + std::vector<Constant*> Initializer(NumEdges); + Constant* zeroc = ConstantInt::get(Int32, 0); + Constant* minusonec = ConstantInt::get(Int32, ProfileInfo::MissingValue); + + // Instrument all of the edges not in MST... + unsigned i = 0; + for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { + if (F->isDeclaration()) continue; + DEBUG(errs()<<"Working on "<<F->getNameStr()<<"\n"); + + PI = &getAnalysisID<ProfileInfo>(ProfileEstimatorPassID,*F); + MaximumSpanningTree MST = MaximumSpanningTree(&(*F),PI,true); + + // Create counter for (0,entry) edge. + BasicBlock *entry = &(F->getEntryBlock()); + ProfileInfo::Edge edge = ProfileInfo::getEdge(0,entry); + if (std::binary_search(MST.begin(),MST.end(),edge)) { + printEdgeCounter(edge,entry,i); + IncrementCounterInBlock(entry, i, Counters); NumEdgesInserted++; + Initializer[i++] = (zeroc); + } else{ + Initializer[i++] = (minusonec); + } + + for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { + if (!BlocksToInstrument.count(BB)) continue; // Don't count new blocks + // Okay, we have to add a counter of each outgoing edge not in MST. 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(); + if (TI->getNumSuccessors() == 0) { + // Create counter for (BB,0), edge. + ProfileInfo::Edge edge = ProfileInfo::getEdge(BB,0); + if (std::binary_search(MST.begin(),MST.end(),edge)) { + printEdgeCounter(edge,BB,i); + IncrementCounterInBlock(BB, i, Counters); NumEdgesInserted++; + Initializer[i++] = (zeroc); + } else{ + Initializer[i++] = (minusonec); + } + } + for (unsigned s = 0, e = TI->getNumSuccessors(); s != e; ++s) { + BasicBlock *Succ = TI->getSuccessor(s); + ProfileInfo::Edge edge = ProfileInfo::getEdge(BB,Succ); + if (std::binary_search(MST.begin(),MST.end(),edge)) { + + // If the edge is critical, split it. + SplitCriticalEdge(TI,s,this); + Succ = TI->getSuccessor(s); + + // 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 + printEdgeCounter(edge,BB,i); + IncrementCounterInBlock(BB, i, Counters); NumEdgesInserted++; + } else { + // Insert counter at the start of the block + printEdgeCounter(edge,Succ,i); + IncrementCounterInBlock(Succ, i, Counters); NumEdgesInserted++; + } + Initializer[i++] = (zeroc); + } else { + Initializer[i++] = (minusonec); + } + } + } + } + + // check if indeed all counters have been used + assert(i==NumEdges && "the number of edges in counting array is wrong"); + + // assign initialiser to array + Constant *init = ConstantArray::get(ATy, Initializer); + Counters->setInitializer(init); + + // Add the initialization call to main. + InsertProfilingInitCall(Main, "llvm_start_opt_edge_profiling", Counters); + return true; +} + diff --git a/runtime/libprofile/OptimalEdgeProfiling.c b/runtime/libprofile/OptimalEdgeProfiling.c new file mode 100644 index 0000000..eb7887b --- /dev/null +++ b/runtime/libprofile/OptimalEdgeProfiling.c @@ -0,0 +1,45 @@ +/*===-- OptimalEdgeProfiling.c - Support library for opt. edge profiling --===*\ +|* +|* The LLVM Compiler Infrastructure +|* +|* This file is distributed under the University of Illinois Open Source +|* License. See LICENSE.TXT for details. +|* +|*===----------------------------------------------------------------------===*| +|* +|* This file implements the call back routines for the edge profiling +|* instrumentation pass. This should be used with the +|* -insert-opt-edge-profiling LLVM pass. +|* +\*===----------------------------------------------------------------------===*/ + +#include "Profiling.h" +#include <stdlib.h> + +static unsigned *ArrayStart; +static unsigned NumElements; + +/* OptEdgeProfAtExitHandler - When the program exits, just write out the + * profiling data. + */ +static void OptEdgeProfAtExitHandler() { + /* Note that, although the array has a counter for each edge, not all + * counters are updated, the ones that are not used are initialised with -1. + * When loading this information the counters with value -1 have to be + * recalculated, it is guranteed that this is possible. + */ + write_profiling_data(OptEdgeInfo, ArrayStart, NumElements); +} + + +/* llvm_start_opt_edge_profiling - This is the main entry point of the edge + * profiling library. It is responsible for setting up the atexit handler. + */ +int llvm_start_opt_edge_profiling(int argc, const char **argv, + unsigned *arrayStart, unsigned numElements) { + int Ret = save_arguments(argc, argv); + ArrayStart = arrayStart; + NumElements = numElements; + atexit(OptEdgeProfAtExitHandler); + return Ret; +} diff --git a/runtime/libprofile/exported_symbols.lst b/runtime/libprofile/exported_symbols.lst index 5fc6559..45c6d5e 100644 --- a/runtime/libprofile/exported_symbols.lst +++ b/runtime/libprofile/exported_symbols.lst @@ -2,5 +2,6 @@ llvm_start_func_profiling llvm_start_block_profiling llvm_start_edge_profiling +llvm_start_opt_edge_profiling llvm_start_basic_block_tracing llvm_trace_basic_block |