[Bitcode] Move Bitstream to a separate library

This moves Bitcode/Bitstream*, Bitcode/BitCodes.h to Bitstream/.

This is needed to avoid a circular dependency when using the bitstream
code for parsing optimization remarks.

Since Bitcode uses Core for the IR part:

libLLVMRemarks -> Bitcode -> Core

and Core uses libLLVMRemarks to generate remarks (see
IR/RemarkStreamer.cpp):

Core -> libLLVMRemarks

we need to separate the Bitstream and Bitcode part.

For clang-doc, it seems that it doesn't need the whole bitcode layer, so
I updated the CMake to only use the bitstream part.

Differential Revision: https://reviews.llvm.org/D63899

llvm-svn: 365091

1 files changed, 58 insertions, 0 deletions

diff --git a/llvm/unittests/Bitstream/BitstreamWriterTest.cpp b/llvm/unittests/Bitstream/BitstreamWriterTest.cpp
new file mode 100644
index 00000000000..993c5aadee2
--- /dev/null
+++ b/llvm/unittests/Bitstream/BitstreamWriterTest.cpp
@@ -0,0 +1,58 @@
+//===- BitstreamWriterTest.cpp - Tests for BitstreamWriter ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Bitstream/BitstreamWriter.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+TEST(BitstreamWriterTest, emitBlob) {
+  SmallString<64> Buffer;
+  BitstreamWriter W(Buffer);
+  W.emitBlob("str", /* ShouldEmitSize */ false);
+  EXPECT_EQ(StringRef("str\0", 4), Buffer);
+}
+
+TEST(BitstreamWriterTest, emitBlobWithSize) {
+  SmallString<64> Buffer;
+  {
+    BitstreamWriter W(Buffer);
+    W.emitBlob("str");
+  }
+  SmallString<64> Expected;
+  {
+    BitstreamWriter W(Expected);
+    W.EmitVBR(3, 6);
+    W.FlushToWord();
+    W.Emit('s', 8);
+    W.Emit('t', 8);
+    W.Emit('r', 8);
+    W.Emit(0, 8);
+  }
+  EXPECT_EQ(StringRef(Expected), Buffer);
+}
+
+TEST(BitstreamWriterTest, emitBlobEmpty) {
+  SmallString<64> Buffer;
+  BitstreamWriter W(Buffer);
+  W.emitBlob("", /* ShouldEmitSize */ false);
+  EXPECT_EQ(StringRef(""), Buffer);
+}
+
+TEST(BitstreamWriterTest, emitBlob4ByteAligned) {
+  SmallString<64> Buffer;
+  BitstreamWriter W(Buffer);
+  W.emitBlob("str0", /* ShouldEmitSize */ false);
+  EXPECT_EQ(StringRef("str0"), Buffer);
+}
+
+} // end namespace