Rebased PNaCl localmods in LLVM to 223109

include/llvm/Bitcode/NaCl/NaClBitcodeMunge.h

Index: include/llvm/Bitcode/NaCl/NaClBitcodeMunge.h
diff --git a/include/llvm/Bitcode/NaCl/NaClBitcodeMunge.h b/include/llvm/Bitcode/NaCl/NaClBitcodeMunge.h
new file mode 100644
index 0000000000000000000000000000000000000000..2281a222a8a43fb8db1cc39fd3196db69bc92031
--- /dev/null
+++ b/include/llvm/Bitcode/NaCl/NaClBitcodeMunge.h
@@ -0,0 +1,286 @@
+//===- NaClBitcodeMunge.h - Bitcode Munger ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Test harness for generating a PNaCl bitcode memory buffer from
+// an array, and parse/objdump the resulting contents.
+//
+// Generates a bitcode memory buffer from an array containing 1 or
+// more PNaCl records. Used to test errors in PNaCl bitcode.
+//
+// For simplicity of API, we model records as an array of uint64_t. To
+// specify the end of a record in the array, a special "terminator"
+// value is used. This terminator value must be a uint64_t value that
+// is not used by any of the records.
+//
+// A record is defined as a sequence of integers consisting of:
+//   * The abbreviation index associated with the record.
+//   * The record code associated with the record.
+//   * The sequence of values associated with the record code.
+//   * The terminator value.
+//
+// Note: Since the header record doesn't have any abbreviation indices
+// associated with it, one can use any value. The value will simply be
+// ignored.
+//
+// In addition to specifying the sequence of records, one can also
+// define a sequence of edits to be applied to the original sequence
+// of records. This allows the same record sequence to be used in
+// multiple tests.
+//
+// An edit consists of:
+//
+//   * A record number defining where the edit is to be applied.
+//   * An action defining the type of edit.
+//   * An optional record associated with the action.
+//
+// Note that edits must be sorted by record number, so that the records
+// and edits can be processed with a linear pass.
+//
+// Generally, you can generate any legal/illegal record
+// sequence. However, abbreviations are intimately tied to the
+// internals of the bitstream writer and can't contain illegal
+// data. Whenever class NaClBitcodeMunger is unable to accept illegal
+// data, a corresponding "Fatal" error is generated and execution
+// is terminated.
+//
+// ===---------------------------------------------------------------------===//
+
+#ifndef LLVM_BITCODE_NACL_NACLBITCODEMUNGE_H
+#define LLVM_BITCODE_NACL_NACLBITCODEMUNGE_H
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <string>
+
+namespace llvm {
+
+class NaClBitstreamWriter;
+class NaClBitCodeAbbrev;
+
+/// Base class to run tests on munged bitcode files.
+class NaClBitcodeMunger {
+public:
+  /// The types of editing actions that can be applied.
+  enum EditAction {
+    AddBefore, // Insert record before record with index.
+    AddAfter,  // Insert record after record with index.
+    Remove,    // Remove record with index.
+    Replace    // Replace record with index with specified record.
+  };
+
+  /// Creates a bitcode munger, based on the given array of values.
+  NaClBitcodeMunger(const uint64_t Records[], size_t RecordsSize,
+                    uint64_t RecordTerminator)
+      : Records(Records), RecordsSize(RecordsSize),
+        RecordTerminator(RecordTerminator), WriteBlockID(-1), SetBID(-1),
+        DumpResults("Error: No previous dump results!\n"),
+        DumpStream(nullptr), Writer(nullptr), FoundErrors(false),
+        FatalBuffer(), FatalStream(FatalBuffer) {}
+
+  /// Creates MungedInput and DumpStream for running tests, based on
+  /// given Munges.
+  void setupTest(
+      const char *TestName, const uint64_t Munges[], size_t MungesSize,
+      bool AddHeader);
+
+  /// Cleans up state after a test.
+  void cleanupTest();
+
+  /// Returns the resulting string generated by the corresponding test.
+  const std::string &getTestResults() const {
+    return DumpResults;
+  }
+
+  /// Returns the lines containing the given Substring, from the
+  /// string getTestResults().
+  std::string getLinesWithSubstring(const std::string &Substring) const {
+    return getLinesWithTextMatch(Substring, false);
+  }
+
+  /// Returns the lines starting with the given Prefix, from the string
+  /// getTestResults().
+  std::string getLinesWithPrefix(const std::string &Prefix) const {
+    return getLinesWithTextMatch(Prefix, true);
+  }
+
+protected:
+  // The list of (base) records.
+  const uint64_t *Records;
+  // The number of (base) records.
+  size_t RecordsSize;
+  // The value used as record terminator.
+  uint64_t RecordTerminator;
+  // The block ID associated with the block being written.
+  int WriteBlockID;
+  // The SetBID for the blockinfo block.
+  int SetBID;
+  // The results buffer of the last dump.
+  std::string DumpResults;
+  // The memory buffer containing the munged input.
+  std::unique_ptr<MemoryBuffer> MungedInput;
+  // The stream containing errors and the objdump of the generated bitcode file.
+  raw_ostream *DumpStream;
+  // The bitstream writer to use to generate the bitcode file.
+  NaClBitstreamWriter *Writer;
+  // True if any errors were reported.
+  bool FoundErrors;
+  // The buffer to hold the generated fatal message.
+  std::string FatalBuffer;
+  // The stream to write the fatal message to.
+  raw_string_ostream FatalStream;
+
+  // Records that an error occurred, and returns stream to print error
+  // message to.
+  raw_ostream &Error() {
+    FoundErrors = true;
+    return *DumpStream << "Error: ";
+  }
+
+  // Returns stream to print fatal error message to.
+  // Note: Once the fatal error message has been dumped to the stream,
+  // one must call ReportFatalError to display the error and terminate
+  // execution.
+  raw_ostream &Fatal() {
+    return FatalStream << "Fatal: ";
+  }
+
+  // Displays the fatal error message and exits the program.
+  void ReportFatalError() {
+    report_fatal_error(FatalStream.str());
+  }
+
+  /// Returns the lines containing the given Substring, from the
+  /// string getTestResults(). If MustBePrefix, then Substring must
+  /// match at the beginning of the line.
+  std::string getLinesWithTextMatch(const std::string &Substring,
+                                    bool MustBePrefix = false) const;
+
+  // Writes out sequence of records, applying the given sequence of
+  // munges.
+  void writeMungedData(const uint64_t Munges[], size_t MungesSize,
+                       bool AddHeader);
+
+  // Emits the given record to the bitcode file.
+  void emitRecord(unsigned AbbrevIndex, unsigned RecordCode,
+                  SmallVectorImpl<uint64_t> &Values);
+
+  // Converts the abbreviation record to the corresponding abbreviation.
+  NaClBitCodeAbbrev *buildAbbrev(unsigned RecordCode,
+                                 SmallVectorImpl<uint64_t> &Values);
+
+  // Emits the record at the given Index to the bitcode file.  Then
+  // updates Index by one.
+  void emitRecordAtIndex(const uint64_t Record[], size_t RecordSize,
+                         size_t &Index);
+
+  // Skips the record starting at Index by advancing Index past the
+  // contents of the record.
+  void deleteRecord(const uint64_t Record[], size_t RecordSize,
+                    size_t &Index);
+};
+
+/// Class to run tests for function llvm::NaClObjDump.
+class NaClObjDumpMunger : public NaClBitcodeMunger {
+public:
+
+  /// Creates a bitcode munger, based on the given array of values.
+  NaClObjDumpMunger(const uint64_t Records[], size_t RecordsSize,
+                    uint64_t RecordTerminator)
+      : NaClBitcodeMunger(Records, RecordsSize, RecordTerminator) {}
+
+  /// Runs function NaClObjDump on the sequence of records associated
+  /// with the instance. The memory buffer containing the bitsequence
+  /// associated with the record is automatically generated, and
+  /// passed to NaClObjDump.  TestName is the name associated with the
+  /// memory buffer.  If AddHeader is true, test assumes that the
+  /// sequence of records doesn't contain a header record, and the
+  /// test should add one. Arguments NoRecords and NoAssembly are
+  /// passed to NaClObjDump. Returns true if test succeeds without
+  /// errors.
+  bool runTestWithFlags(const char *TestName, bool AddHeader,
+                        bool NoRecords, bool NoAssembly) {
+    uint64_t NoMunges[] = {0};
+    return runTestWithFlags(TestName, NoMunges, 0, AddHeader, NoRecords,
+                            NoAssembly);
+  }
+
+  /// Same as above except it runs function NaClObjDump with flags
+  /// NoRecords and NoAssembly set to false, and AddHeader set to true.
+  bool runTest(const char *TestName) {
+    return runTestWithFlags(TestName, true, false, false);
+  }
+
+  /// Same as runTest, but only print out assembly and errors.
+  bool runTestForAssembly(const char *TestName) {
+    return runTestWithFlags(TestName, true, true, false);
+  }
+
+  /// Same as runTest, but only generate error messages.
+  bool runTestForErrors(const char *TestName) {
+    return runTestWithFlags(TestName, true, true, true);
+  }
+
+  /// Runs function llvm::NaClObjDump on the sequence of records
+  /// associated with the instance. Array Munges contains the sequence
+  /// of edits to apply to the sequence of records when generating the
+  /// bitsequence in a memory buffer. This generated bitsequence is
+  /// then passed to NaClObjDump.  TestName is the name associated
+  /// with the memory buffer.  Arguments NoRecords and NoAssembly are
+  /// passed to NaClObjDump. Returns true if test succeeds without
+  /// errors.
+  bool runTestWithFlags(const char* TestName, const uint64_t Munges[],
+                        size_t MungesSize, bool AddHeader,
+                        bool NoRecords, bool NoAssembly);
+
+  /// Same as above except it runs function NaClObjDump with flags
+  /// NoRecords and NoAssembly set to false, and AddHeader set to
+  /// true.
+  bool runTest(const char* TestName, const uint64_t Munges[],
+                      size_t MungesSize) {
+    return runTestWithFlags(TestName, Munges, MungesSize, true, false, false);
+  }
+
+  bool runTestForAssembly(const char* TestName, const uint64_t Munges[],
+                          size_t MungesSize) {
+    return runTestWithFlags(TestName, Munges, MungesSize, true, true, false);
+  }
+
+  bool runTestForErrors(const char* TestName, const uint64_t Munges[],
+                        size_t MungesSize) {
+    return runTestWithFlags(TestName, Munges, MungesSize, true, true, true);
+  }
+};
+
+// Class to run tests for function NaClParseBitcodeFile.
+class NaClParseBitcodeMunger : public NaClBitcodeMunger {
+public:
+  NaClParseBitcodeMunger(const uint64_t Records[], size_t RecordsSize,
+                    uint64_t RecordTerminator)
+      : NaClBitcodeMunger(Records, RecordsSize, RecordTerminator) {}
+
+  /// Runs function llvm::NaClParseBitcodeFile, and puts error messages
+  /// into DumpResults. Returns true if parse is successful.
+  bool runTest(const char* TestName, const uint64_t Munges[],
+               size_t MungesSize, bool VerboseErrors);
+
+  // Same as above, but without any edits.
+  bool runTest(const char* TestName, bool VerboseErrors) {
+    uint64_t NoMunges[] = {0};
+    return runTest(TestName, NoMunges, 0, VerboseErrors);
+  }
+};
+
+} // end namespace llvm.
+
+#endif // LLVM_BITCODE_NACL_NACLBITCODEMUNGE_H