Rebased PNaCl localmods in LLVM to 223109

tools/pnacl-benchmark/pnacl-benchmark.cpp

Index: tools/pnacl-benchmark/pnacl-benchmark.cpp
diff --git a/tools/pnacl-benchmark/pnacl-benchmark.cpp b/tools/pnacl-benchmark/pnacl-benchmark.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..3bd5f256b00725eaa18ffeb30ec09f00ce5728f5
--- /dev/null
+++ b/tools/pnacl-benchmark/pnacl-benchmark.cpp
@@ -0,0 +1,234 @@
+//===-- pnacl-benchmark.cpp -----------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// pnacl-benchmark: various benchmarking tools for the PNaCl LLVM toolchain.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Bitcode/NaCl/NaClBitcodeAnalyzer.h"
+#include "llvm/Bitcode/NaCl/NaClBitcodeHeader.h"
+#include "llvm/Bitcode/NaCl/NaClBitcodeParser.h"
+#include "llvm/Bitcode/NaCl/NaClBitstreamReader.h"
+#include "llvm/Bitcode/NaCl/NaClLLVMBitCodes.h"
+#include "llvm/Bitcode/NaCl/NaClReaderWriter.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/PrettyStackTrace.h"
+#include "llvm/Support/Signals.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Support/Timer.h"
+#include <memory>
+#include <system_error>
+#include <vector>
+
+using namespace llvm;
+
+
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
+
+static cl::opt<unsigned>
+NumRuns("num-runs", cl::desc("Number of runs"), cl::init(1));
+
+static cl::opt<bool>
+VerboseErrors(
+    "verbose-parse-errors",
+    cl::desc("Print out more descriptive PNaCl bitcode parse errors"),
+    cl::init(false));
+
+/// Used in a lexical block to measure and report the block's execution time.
+///
+/// \param N block name
+/// \param InputSize optional size of input operated upon. If given, the
+///                  throughput will be reported as well in MB/sec.
+class TimingOperationBlock {
+public:
+  TimingOperationBlock(StringRef N, size_t InputSize=0)
+    : InputSize(InputSize) {
+    outs() << "Timing: " << N << "... ";
+    TStart = TimeRecord::getCurrentTime(true);
+  }
+
+  ~TimingOperationBlock() {
+    TimeRecord TEnd = TimeRecord::getCurrentTime(false);
+    double elapsed = TEnd.getWallTime() - TStart.getWallTime();
+    outs() << format("%.3lf", elapsed) << " sec";
+
+    if (InputSize != 0) {
+      double MBPerSec = (InputSize / elapsed) / 1000000.0;
+      outs() << format(" [%.3lf MB/sec]", MBPerSec);
+    }
+    outs() << "\n";
+  }
+private:
+  TimeRecord TStart;
+  size_t InputSize;
+};
+
+/// Simple parsing of bitcode with some basic bookkeeping that simulates doing
+/// "something" with it.
+class DummyBitcodeParser : public NaClBitcodeParser {
+public:
+  DummyBitcodeParser(NaClBitstreamCursor &Cursor)
+    : NaClBitcodeParser(Cursor) {
+    resetCounters();
+  }
+
+  DummyBitcodeParser(unsigned BlockID, DummyBitcodeParser *EnclosingBlock)
+    : NaClBitcodeParser(BlockID, EnclosingBlock) {
+    resetCounters();
+  }
+
+  virtual bool ParseBlock(unsigned BlockID) {
+    DummyBitcodeParser Parser(BlockID, this);
+    return Parser.ParseThisBlock();
+  }
+
+  virtual void EnterBlock(unsigned NumberWords) {
+    NumBlocks++;
+    BlockNames.push_back("<unknown>");
+  }
+
+  virtual void ProcessRecord() {
+    NumRecords++;
+    RecordCodes.push_back(Record.GetCode());
+
+    const NaClBitcodeRecord::RecordVector &Values = Record.GetValues();
+    for (unsigned i = 0, e = Values.size(); i != e; ++i) {
+      RecordValues.push_back((int64_t) Values[i]);
+    }
+  }
+
+private:
+  void resetCounters() {
+    NumBlocks = NumRecords = 0;
+    BlockNames.clear();
+    RecordCodes.clear();
+    RecordValues.clear();
+  }
+
+  uint64_t NumBlocks, NumRecords;
+  std::vector<StringRef> BlockNames;
+  std::vector<unsigned> RecordCodes;
+  std::vector<StringRef> RecordCodeNames;
+  std::vector<int64_t> RecordValues;
+};
+
+void BenchmarkIRParsing() {
+  outs() << "Benchmarking IR parsing...\n";
+  ErrorOr<std::unique_ptr<MemoryBuffer>> ErrOrFile =
+      MemoryBuffer::getFileOrSTDIN(InputFilename);
+  if (std::error_code EC = ErrOrFile.getError())
+    report_fatal_error("Could not open input file: " + EC.message());
+
+  std::unique_ptr<MemoryBuffer> FileBuf(ErrOrFile.get().release());
+  size_t BufSize = FileBuf->getBufferSize();
+  const uint8_t *BufPtr =
+      reinterpret_cast<const uint8_t *>(FileBuf->getBufferStart());
+  const uint8_t *EndBufPtr =
+      reinterpret_cast<const uint8_t *>(FileBuf->getBufferEnd());
+
+  // Since MemoryBuffer may use mmap, make sure to first touch all bytes in the
+  // input buffer to make sure it's actually in memory.
+  volatile uint8_t *Slot = new uint8_t;
+  for (const uint8_t *S = BufPtr; S != EndBufPtr; ++S) {
+    *Slot = *S;
+  }
+
+  delete Slot;
+  outs() << "Read bitcode into buffer. Size=" << BufSize << "\n";
+
+  // Trivial copy into a new buffer with a cascading XOR that simulates
+  // "touching" every byte in the buffer in a simple way.
+  {
+    TimingOperationBlock T("Simple XOR copy", BufSize);
+    volatile uint8_t *OutBuf = new uint8_t[BufSize];
+    OutBuf[0] = 1;
+    size_t N = 1;
+    // Run over the input buffer from start to end-1; run over the output buffer
+    // from 1 to end.
+    for (const uint8_t *S = BufPtr; S != EndBufPtr - 1; ++S, ++N) {
+      OutBuf[N] = OutBuf[N - 1] ^ *S;
+    }
+    delete[] OutBuf;
+  }
+
+  // Simulate simple bitcode parsing. See DummyBitcodeParser for more details.
+  {
+    TimingOperationBlock T("Bitcode block parsing", BufSize);
+    NaClBitcodeHeader Header;
+
+    if (Header.Read(BufPtr, EndBufPtr)) {
+      report_fatal_error("Invalid PNaCl bitcode header");
+    }
+
+    if (!Header.IsSupported()) {
+      errs() << "Warning: " << Header.Unsupported() << "\n";
+    }
+
+    if (!Header.IsReadable()) {
+      report_fatal_error("Bitcode file is not readable");
+    }
+
+    NaClBitstreamReader StreamFile(BufPtr, EndBufPtr);
+    NaClBitstreamCursor Stream(StreamFile);
+    DummyBitcodeParser Parser(Stream);
+    while (!Stream.AtEndOfStream()) {
+      if (Parser.Parse()) {
+        report_fatal_error("Parsing failed");
+      }
+    }
+  }
+
+  // Running bitcode analysis (what bcanalyzer does).
+  // Note that quite a bit of time here is spent on emitting I/O into nulls().
+  {
+    TimingOperationBlock T("Running bitcode analysis", BufSize);
+
+    AnalysisDumpOptions DumpOptions;
+    AnalyzeBitcodeInBuffer(FileBuf, nulls(), DumpOptions);
+  }
+
+  // Actual LLVM IR parsing and formation from the bitcode
+  {
+    TimingOperationBlock T("LLVM IR parsing", BufSize);
+    SMDiagnostic Err;
+    raw_ostream *Verbose = VerboseErrors ? &errs() : nullptr;
+    std::unique_ptr<Module> M = NaClParseIRFile(
+        InputFilename, PNaClFormat,
+        Err, Verbose, getGlobalContext());
+
+    if (!M) {
+      report_fatal_error("Unable to NaClParseIRFile");
+    }
+  }
+}
+
+int main(int argc, char **argv) {
+  sys::PrintStackTraceOnErrorSignal();
+  PrettyStackTraceProgram X(argc, argv);
+
+  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
+  cl::ParseCommandLineOptions(argc, argv, "pnacl-benchmark\n");
+
+  for (unsigned i = 0; i < NumRuns; i++) {
+    BenchmarkIRParsing();
+  }
+
+  return 0;
+}