BitcodeWriter: Expose less implementation details -- make BackpatchWord private
and remove getBuffer().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151748 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 7078169..c6c7fb7 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -1774,7 +1774,18 @@
DarwinBCHeaderSize = 5*4
};
-static void EmitDarwinBCHeader(BitstreamWriter &Stream, const Triple &TT) {
+static void WriteInt32ToBuffer(uint32_t Value,
+ std::vector<unsigned char> &Buffer,
+ uint32_t &Position) {
+ Buffer[Position + 0] = (unsigned char) (Value >> 0);
+ Buffer[Position + 1] = (unsigned char) (Value >> 8);
+ Buffer[Position + 2] = (unsigned char) (Value >> 16);
+ Buffer[Position + 3] = (unsigned char) (Value >> 24);
+ Position += 4;
+}
+
+static void EmitDarwinBCHeaderAndTrailer(std::vector<unsigned char> &Buffer,
+ const Triple &TT) {
unsigned CPUType = ~0U;
// Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
@@ -1801,62 +1812,55 @@
CPUType = DARWIN_CPU_TYPE_ARM;
// Traditional Bitcode starts after header.
+ assert(Buffer.size() >= DarwinBCHeaderSize &&
+ "Expected header size to be reserved");
unsigned BCOffset = DarwinBCHeaderSize;
+ unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
- Stream.Emit(0x0B17C0DE, 32);
- Stream.Emit(0 , 32); // Version.
- Stream.Emit(BCOffset , 32);
- Stream.Emit(0 , 32); // Filled in later.
- Stream.Emit(CPUType , 32);
-}
-
-/// EmitDarwinBCTrailer - Emit the darwin epilog after the bitcode file and
-/// finalize the header.
-static void EmitDarwinBCTrailer(BitstreamWriter &Stream, unsigned BufferSize) {
- // Update the size field in the header.
- Stream.BackpatchWord(DarwinBCSizeFieldOffset, BufferSize-DarwinBCHeaderSize);
+ // Write the magic and version.
+ unsigned Position = 0;
+ WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
+ WriteInt32ToBuffer(0 , Buffer, Position); // Version.
+ WriteInt32ToBuffer(BCOffset , Buffer, Position);
+ WriteInt32ToBuffer(BCSize , Buffer, Position);
+ WriteInt32ToBuffer(CPUType , Buffer, Position);
// If the file is not a multiple of 16 bytes, insert dummy padding.
- while (BufferSize & 15) {
- Stream.Emit(0, 8);
- ++BufferSize;
- }
+ while (Buffer.size() & 15)
+ Buffer.push_back(0);
}
-static void WriteBitcodeToStream(const Module *M, BitstreamWriter &Stream);
-
/// WriteBitcodeToFile - Write the specified module to the specified output
/// stream.
void llvm::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
std::vector<unsigned char> Buffer;
- BitstreamWriter Stream(Buffer);
-
Buffer.reserve(256*1024);
- WriteBitcodeToStream( M, Stream );
+ // If this is darwin or another generic macho target, reserve space for the
+ // header.
+ Triple TT(M->getTargetTriple());
+ if (TT.isOSDarwin())
+ Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
+
+ // Emit the module into the buffer.
+ {
+ BitstreamWriter Stream(Buffer);
+
+ // Emit the file header.
+ Stream.Emit((unsigned)'B', 8);
+ Stream.Emit((unsigned)'C', 8);
+ Stream.Emit(0x0, 4);
+ Stream.Emit(0xC, 4);
+ Stream.Emit(0xE, 4);
+ Stream.Emit(0xD, 4);
+
+ // Emit the module.
+ WriteModule(M, Stream);
+ }
+
+ if (TT.isOSDarwin())
+ EmitDarwinBCHeaderAndTrailer(Buffer, TT);
// Write the generated bitstream to "Out".
Out.write((char*)&Buffer.front(), Buffer.size());
}
-
-static void WriteBitcodeToStream(const Module *M, BitstreamWriter &Stream) {
- // If this is darwin or another generic macho target, emit a file header and
- // trailer if needed.
- Triple TT(M->getTargetTriple());
- if (TT.isOSDarwin())
- EmitDarwinBCHeader(Stream, TT);
-
- // Emit the file header.
- Stream.Emit((unsigned)'B', 8);
- Stream.Emit((unsigned)'C', 8);
- Stream.Emit(0x0, 4);
- Stream.Emit(0xC, 4);
- Stream.Emit(0xE, 4);
- Stream.Emit(0xD, 4);
-
- // Emit the module.
- WriteModule(M, Stream);
-
- if (TT.isOSDarwin())
- EmitDarwinBCTrailer(Stream, Stream.getBuffer().size());
-}