Rebased PNaCl localmods in LLVM to 223109

unittests/Bitcode/NaClBitstreamReaderTest.cpp

+//===- llvm/unittest/Bitcode/NaClBitstreamReaderTest.cpp ------------------===//
+//     Tests issues in NaCl Bitstream Reader.
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// Tests issues in NaCl Bitstream Reader.
+
+// TODO(kschimpf) Add more Tests.
+
+#include "llvm/Bitcode/NaCl/NaClBitstreamReader.h"
+
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+static const uint64_t BitZero = 0;
+
+// Initializes array to sequence of alternating zeros/ones.
+void* InitAltOnes(uint8_t *Array, size_t ArraySize) {
+  for (size_t i = 0; i <ArraySize; ++i) {
+    Array[i] = 0x9;
+  }
+  return Array;
+}
+
+// Tests that the default bitstream cursor is at bit zero.
+TEST(NaClBitstreamTest, DefaultCursorAtBitZero) {
+  uint8_t CursorMemory[sizeof(NaClBitstreamCursor)];
+  NaClBitstreamCursor *Cursor =
+      new (InitAltOnes(CursorMemory, sizeof(NaClBitstreamCursor)))
+      NaClBitstreamCursor();
+  EXPECT_EQ(BitZero, Cursor->GetCurrentBitNo());
+}
+
+// Tests that when we initialize the bitstream cursor with a default bitstream
+// reader, the cursor is at bit zero.
+TEST(NaClBitstreamTest, CursorOnDefaultReaderAtBitZero) {
+  NaClBitstreamReader Reader;
+  uint8_t CursorMemory[sizeof(NaClBitstreamCursor)];
+  NaClBitstreamCursor *Cursor =
+      new (InitAltOnes(CursorMemory, sizeof(NaClBitstreamCursor)))
+      NaClBitstreamCursor(Reader);
+  EXPECT_EQ(BitZero, Cursor->GetCurrentBitNo());
+}
+
+// Tests that when we initialize the bitstream cursor with an array-filled
+// bitstream reader, the cursor is at bit zero.
+TEST(NaClBitstreamTest, ReaderCursorAtBitZero) {
+  static const size_t BufferSize = 12;
+  unsigned char Buffer[BufferSize];
+  NaClBitstreamReader Reader(Buffer, Buffer+BufferSize);
+  uint8_t CursorMemory[sizeof(NaClBitstreamCursor)];
+  NaClBitstreamCursor *Cursor =
+      new (InitAltOnes(CursorMemory, sizeof(NaClBitstreamCursor)))
+      NaClBitstreamCursor(Reader);
+  EXPECT_EQ(BitZero, Cursor->GetCurrentBitNo());
+}
+
+TEST(NaClBitstreamTest, CursorAtReaderInitialAddress) {
+  static const size_t BufferSize = 12;
+  static const size_t InitialAddress = 8;
+  unsigned char Buffer[BufferSize];
+  NaClBitstreamReader Reader(Buffer, Buffer+BufferSize, InitialAddress);
+  uint8_t CursorMemory[sizeof(NaClBitstreamCursor)];
+  NaClBitstreamCursor *Cursor =
+      new (InitAltOnes(CursorMemory, sizeof(NaClBitstreamCursor)))
+      NaClBitstreamCursor(Reader);
+  EXPECT_EQ(InitialAddress * CHAR_BIT, Cursor->GetCurrentBitNo());
+}
+
+} // end of anonymous namespace