Rebased PNaCl localmods in LLVM to 223109

lib/Bitcode/NaCl/Analysis/NaClBitcodeAnalyzer.cpp

+//===-- NaClBitcodeAnalyzer.cpp - Bitcode Analyzer ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "nacl-bitcode-analyzer"
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Bitcode/NaCl/NaClAnalyzerBlockDist.h"
+#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/Support/Debug.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <map>
+#include <system_error>
+
+// TODO(kschimpf): Separate out into two bitcode parsers, one for
+// dumping records, and one for collecting distribution stats for
+// printing. This should simplify the code.
+
+/// Error - All bitcode analysis errors go through this function, making this a
+/// good place to breakpoint if debugging.
+static bool Error(const llvm::Twine &Err) {
+  llvm::errs() << Err << "\n";
+  return true;
+}
+
+namespace llvm {
+
+// Parses all bitcode blocks, and collects distribution of records in
+// each block.  Also dumps bitcode structure if specified (via global
+// variables).
+class PNaClBitcodeAnalyzerParser : public NaClBitcodeParser {
+public:
+  PNaClBitcodeAnalyzerParser(NaClBitstreamCursor &Cursor,
+                             raw_ostream &OS,
+                             const AnalysisDumpOptions &DumpOptions,
+                             NaClBitcodeDist *Dist)
+    : NaClBitcodeParser(Cursor),
+      IndentLevel(0),
+      OS(OS),
+      DumpOptions(DumpOptions),
+      Dist(Dist),
+      AbbrevListener(this)
+  {
+    SetListener(&AbbrevListener);
+  }
+
+  virtual ~PNaClBitcodeAnalyzerParser() {}
+
+  virtual bool Error(const std::string &Message) {
+    // Use local error routine so that all errors are treated uniformly.
+    return ::Error(Message);
+  }
+
+  virtual bool ParseBlock(unsigned BlockID);
+
+  // Returns the string defining the indentation to use with respect
+  // to the current indent level.
+  const std::string &GetIndentation() {
+    size_t Size = IndentationCache.size();
+    if (IndentLevel >= Size) {
+      IndentationCache.resize(IndentLevel+1);
+      for (size_t i = Size; i <= IndentLevel; ++i) {
+        IndentationCache[i] = std::string(i*2, ' ');
+      }
+    }
+    return IndentationCache[IndentLevel];
+  }
+
+  // Keeps track of current indentation level based on block nesting.
+  unsigned IndentLevel;
+  // The output stream to print to.
+  raw_ostream &OS;
+  // The dump options to use.
+  const AnalysisDumpOptions &DumpOptions;
+  // The bitcode distribution map (if defined) to update.
+  NaClBitcodeDist *Dist;
+
+private:
+  // The set of cached, indentation strings. Used for indenting
+  // records when dumping.
+  std::vector<std::string> IndentationCache;
+  // Listener used to get abbreviations as they are read.
+  NaClBitcodeParserListener AbbrevListener;
+};
+
+// Parses a bitcode block, and collects distribution of records in that block.
+// Also dumps bitcode structure if specified (via global variables).
+class PNaClBitcodeAnalyzerBlockParser : public NaClBitcodeParser {
+public:
+  // Parses top-level block.
+  PNaClBitcodeAnalyzerBlockParser(
+      unsigned BlockID,
+      PNaClBitcodeAnalyzerParser *Parser)
+      : NaClBitcodeParser(BlockID, Parser) {
+    Initialize(BlockID, Parser);
+  }
+
+  virtual ~PNaClBitcodeAnalyzerBlockParser() {
+    if (Context->Dist) Context->Dist->AddBlock(GetBlock());
+  }
+
+  // *****************************************************
+  // This subsection Defines an XML generator for the dump.
+  // Tag. TagName, Attribute
+  // *****************************************************
+
+private:
+  // The tag name for an element.
+  std::string TagName;
+  // The number of attributes associated with a tag.
+  unsigned NumTagAttributes;
+  // The number of (indexed attribute) operands associated with a tag.
+  unsigned NumTagOperands;
+
+protected:
+
+  /// Initializes internal data used to emit an XML tag.
+  void InitializeEmitTag() {
+    TagName.clear();
+    NumTagAttributes = 0;
+    NumTagOperands = 0;
+  }
+
+  /// Emits the start of an XML start tag.
+  void EmitBeginStartTag() {
+    InitializeEmitTag();
+    Context->OS << Indent << "<";
+  }
+
+  /// Emit the start of an XML end tag.
+  void EmitBeginEndTag() {
+    InitializeEmitTag();
+    Context->OS << Indent << "</";
+  }
+
+  /// Emits the end of an empty-element XML tag.
+  void EmitEndTag() {
+    Context->OS << "/>\n";
+  }
+
+  /// Emits the End of a start/end tag for an XML element.
+  void EmitEndElementTag() {
+    Context->OS << ">\n";
+  }
+
+  /// Emits the tag name for an XML tag.
+  void EmitTagName(const std::string &ElmtName) {
+    TagName = ElmtName;
+    Context->OS << ElmtName;
+  }
+
+  /// Emits the "name=" portion of an XML tag attribute.
+  raw_ostream &EmitAttributePrefix(const std::string &AttributeName) {
+    WrapOperandsLine();
+    Context->OS << " " << AttributeName << "=";
+    ++NumTagAttributes;
+    return Context->OS;
+  }
+
+  /// Emits a string-valued XML attribute of an XML tag.
+  void EmitStringAttribute(const char *AttributeName, const std::string &Str) {
+    EmitAttributePrefix(AttributeName) << "'" << Str << "'";
+  }
+
+  /// Emits a string-valued XML attribute of an XML tag.
+  void EmitStringAttribute(const char *AttributeName, const char*Str) {
+    std::string StrStr(Str);
+    EmitStringAttribute(AttributeName, StrStr);
+  }
+
+  /// Emits an unsigned integer-valued XML attribute of an XML tag.
+  void EmitAttribute(const char *AttributeName, uint64_t Value) {
+    EmitAttributePrefix(AttributeName) << Value;
+  }
+
+  /// Emits the "opN=" portion of an XML tag (indexable) operand attribute.
+  raw_ostream &EmitOperandPrefix() {
+    std::string OpName;
+    raw_string_ostream OpNameStrm(OpName);
+    OpNameStrm << "op" << NumTagOperands;
+    ++NumTagOperands;
+    return EmitAttributePrefix(OpNameStrm.str());
+  }
+
+  /// Adds line wrap if more than "OpsPerLine" XML tag attributes are
+  /// emitted on the current line.
+  void WrapOperandsLine() {
+    if (Context->DumpOptions.OpsPerLine) {
+      if (NumTagAttributes &&
+          (NumTagAttributes % Context->DumpOptions.OpsPerLine) == 0) {
+        raw_ostream &OS = Context->OS;
+        // Last operand crossed width boundary, add newline and indent.
+        OS << "\n" << Indent << " ";
+        for (unsigned J = 0, SZ = TagName.size(); J < SZ; ++J)
+          OS << " ";
+      }
+    }
+  }
+
+  // ********************************************************
+  // This section defines how to parse the block and generate
+  // the corresponding XML.
+  // ********************************************************
+
+  // Parses nested blocks.
+  PNaClBitcodeAnalyzerBlockParser(
+      unsigned BlockID,
+      PNaClBitcodeAnalyzerBlockParser *EnclosingBlock)
+      : NaClBitcodeParser(BlockID, EnclosingBlock),
+        Context(EnclosingBlock->Context) {
+    Initialize(BlockID, EnclosingBlock->Context);
+  }
+
+  // Initialize data associated with a block.
+  void Initialize(unsigned BlockID, PNaClBitcodeAnalyzerParser *Parser) {
+    InitializeEmitTag();
+    Context = Parser;
+    if (Context->DumpOptions.DumpRecords) {
+      Indent = Parser->GetIndentation();
+    }
+    NumWords = 0;
+  }
+
+  // Increment the indentation level for dumping.
+  void IncrementIndent() {
+    Context->IndentLevel++;
+    Indent = Context->GetIndentation();
+  }
+
+  // Increment the indentation level for dumping.
+  void DecrementIndent() {
+    Context->IndentLevel--;
+    Indent = Context->GetIndentation();
+  }
+
+  virtual bool Error(const std::string &Message) {
+    // Use local error routine so that all errors are treated uniformly.
+    return ::Error(Message);
+  }
+
+  // Called once the block has been entered by the bitstream reader.
+  // Argument NumWords is set to the number of words in the
+  // corresponding block.
+  virtual void EnterBlock(unsigned NumberWords) {
+    NumWords = NumberWords;
+    if (Context->DumpOptions.DumpRecords) {
+      unsigned BlockID = GetBlockID();
+      EmitBeginStartTag();
+      EmitEnterBlockTagName(BlockID);
+      if (Context->DumpOptions.DumpDetails) {
+        EmitAttribute("NumWords", NumWords);
+        EmitAttribute("BlockCodeSize", Record.GetCursor().getAbbrevIDWidth());
+      }
+      if (!Context->DumpOptions.DumpDetails &&
+          naclbitc::BLOCKINFO_BLOCK_ID == GetBlockID()) {
+        EmitEndTag();
+      } else {
+        EmitEndElementTag();
+        IncrementIndent();
+      }
+    }
+  }
+
+  // Called when the corresponding EndBlock of the block being parsed
+  // is found.
+  virtual void ExitBlock() {
+    if (Context->DumpOptions.DumpRecords) {
+      if (!Context->DumpOptions.DumpDetails &&
+          naclbitc::BLOCKINFO_BLOCK_ID == GetBlockID())
+        return;
+      DecrementIndent();
+      EmitBeginEndTag();
+      EmitExitBlockTagName(Record.GetBlockID());
+      EmitEndElementTag();
+    }
+  }
+
+  virtual void SetBID() {
+    if (!(Context->DumpOptions.DumpRecords &&
+          Context->DumpOptions.DumpDetails)) {
+      return;
+    }
+    EmitBeginStartTag();
+    EmitCodeTagName(naclbitc::BLOCKINFO_CODE_SETBID,
+                    naclbitc::BLOCKINFO_BLOCK_ID);
+    EmitStringAttribute("block",
+                        NaClBitcodeBlockDist::GetName(Record.GetValues()[0]));
+    EmitEndTag();
+  }
+
+  virtual void ProcessAbbreviation(unsigned BlockID,
+                                   NaClBitCodeAbbrev *Abbrev,
+                                   bool IsLocal) {
+    if (Context->DumpOptions.DumpDetails) {
+      EmitAbbreviation(Abbrev);
+    }
+  }
+
+  // Process the last read record in the block.
+  virtual void ProcessRecord() {
+    // Increment the # occurrences of this code.
+    if (Context->Dist) Context->Dist->AddRecord(Record);
+
+    if (Context->DumpOptions.DumpRecords) {
+      EmitBeginStartTag();
+      EmitCodeTagName(Record.GetCode(), GetBlockID(), Record.GetEntryID());
+      const NaClBitcodeRecord::RecordVector &Values = Record.GetValues();
+      for (unsigned i = 0, e = Values.size(); i != e; ++i) {
+        EmitOperandPrefix() << (int64_t)Values[i];
+      }
+      EmitEndTag();
+    }
+  }
+
+  virtual bool ParseBlock(unsigned BlockID) {
+    PNaClBitcodeAnalyzerBlockParser Parser(BlockID, this);
+    return Parser.ParseThisBlock();
+  }
+
+private:
+  /// Defines the indent level of the block being parsed.
+  std::string Indent;
+  /// Defines the number of (32-bit) words the block occupies in
+  /// the bitstream.
+  unsigned NumWords;
+  /// Refers to global parsing context.
+  PNaClBitcodeAnalyzerParser *Context;
+
+protected:
+
+  /// Emit the given abbreviation as an XML tag.
+  void EmitAbbreviation(const NaClBitCodeAbbrev *Abbrev) {
+    EmitBeginStartTag();
+    EmitTagName("DEFINE_ABBREV");
+    if (Context->DumpOptions.DumpDetails) {
+      EmitStringAttribute("abbrev", "DEFINE_ABBREV");
+    }
+    for (unsigned I = 0, IEnd = Abbrev->getNumOperandInfos(); I != IEnd; ++I) {
+      EmitAbbreviationOp(Abbrev->getOperandInfo(I));
+    }
+    EmitEndTag();
+  }
+
+  /// Emit the given abbreviation operand as an XML tag attribute.
+  void EmitAbbreviationOp(const NaClBitCodeAbbrevOp &Op) {
+    EmitOperandPrefix()
+        << "'" << NaClBitCodeAbbrevOp::getEncodingName(Op.getEncoding());
+    if (Op.hasValue()) {
+      Context->OS << "(" << Op.getValue() << ")";
+    }
+    Context->OS << "'";
+  }
+
+  /// Emits the symbolic name of the record code as the XML tag name.
+  void EmitCodeTagName(
+      unsigned CodeID, unsigned BlockID,
+      unsigned AbbreviationID = naclbitc::UNABBREV_RECORD) {
+    EmitTagName(NaClBitcodeCodeDist::GetCodeName(CodeID, BlockID));
+    if (Context->DumpOptions.DumpDetails) {
+      if (AbbreviationID == naclbitc::UNABBREV_RECORD) {
+        EmitStringAttribute("abbrev", "UNABBREVIATED");
+      } else {
+        EmitAttribute("abbrev", AbbreviationID);
+      }
+    }
+  }
+
+  /// Emits the symbolic name of the block as the XML tag name.
+  void EmitEnterBlockTagName(unsigned BlockID) {
+    EmitTagName(NaClBitcodeBlockDist::GetName(BlockID));
+    if (Context->DumpOptions.DumpDetails)
+      EmitStringAttribute("abbrev", "ENTER_SUBBLOCK");
+  }
+
+  /// Emits the symbolic name of the block as the the XML tag name.
+  void EmitExitBlockTagName(unsigned BlockID) {
+    EmitTagName(NaClBitcodeBlockDist::GetName(BlockID));
+    if (Context->DumpOptions.DumpDetails)
+      EmitStringAttribute("abbrev", "END_BLOCK");
+  }
+};
+
+bool PNaClBitcodeAnalyzerParser::ParseBlock(unsigned BlockID) {
+  PNaClBitcodeAnalyzerBlockParser Parser(BlockID, this);
+  return Parser.ParseThisBlock();
+}
+
+static void PrintSize(uint64_t Bits, raw_ostream &OS) {
+  OS << format("%lub/%.2fB/%luW", (unsigned long)Bits,
+               (double)Bits/8, (unsigned long)(Bits/32));
+}
+
+int AnalyzeBitcodeInBuffer(const std::unique_ptr<MemoryBuffer> &Buf,
+                           raw_ostream &OS,
+                           const AnalysisDumpOptions &DumpOptions) {
+  DEBUG(dbgs() << "-> AnalyzeBitcodeInBuffer\n");
+
+  if (Buf->getBufferSize() & 3)
+    return Error("Bitcode stream should be a multiple of 4 bytes in length");
+
+  const unsigned char *BufPtr = (const unsigned char *)Buf->getBufferStart();
+  const unsigned char *EndBufPtr = BufPtr + Buf->getBufferSize();
+
+  NaClBitcodeHeader Header;
+  if (Header.Read(BufPtr, EndBufPtr))
+    return Error("Invalid PNaCl bitcode header");
+
+  if (!Header.IsSupported())
+    errs() << "Warning: " << Header.Unsupported() << "\n";
+
+  if (!Header.IsReadable())
+    Error("Bitcode file is not readable");
+
+  NaClBitstreamReader StreamFile(BufPtr, EndBufPtr);
+  NaClBitstreamCursor Stream(StreamFile);
+
+  unsigned NumTopBlocks = 0;
+
+  // Print out header information.
+  for (size_t i = 0, limit = Header.NumberFields(); i < limit; ++i) {
+    OS << Header.GetField(i)->Contents() << "\n";
+  }
+  if (Header.NumberFields()) OS << "\n";
+
+  // Parse the top-level structure.  We only allow blocks at the top-level.
+  NaClAnalyzerBlockDistElement DistSentinel(0, DumpOptions.OrderBlocksByID);
+  NaClAnalyzerBlockDist Dist(DistSentinel);
+  PNaClBitcodeAnalyzerParser Parser(Stream, OS, DumpOptions, &Dist);
+  while (!Stream.AtEndOfStream()) {
+    ++NumTopBlocks;
+    if (Parser.Parse()) return 1;
+  }
+
+  if (DumpOptions.DumpRecords) return 0;
+
+  uint64_t BufferSizeBits = (EndBufPtr-BufPtr)*CHAR_BIT;
+  // Print a summary
+  OS << "Total size: ";
+  PrintSize(BufferSizeBits, OS);
+  OS << "\n";
+  OS << "# Toplevel Blocks: " << NumTopBlocks << "\n";
+  OS << "\n";
+
+  if (Parser.Dist) Parser.Dist->Print(OS);
+
+  DEBUG(dbgs() << "<- AnalyzeBitcode\n");
+  return 0;
+}
+
+int AnalyzeBitcodeInFile(const StringRef &InputFilename, raw_ostream &OS,
+                         const AnalysisDumpOptions &DumpOptions) {
+  ErrorOr<std::unique_ptr<MemoryBuffer>> ErrOrFile =
+      MemoryBuffer::getFileOrSTDIN(InputFilename);
+  if (std::error_code EC = ErrOrFile.getError())
+    return Error(Twine("Error reading '") + InputFilename + "': " +
+                 EC.message());
+
+  return AnalyzeBitcodeInBuffer(ErrOrFile.get(), OS, DumpOptions);
+}
+
+} // namespace llvm