}
}
-// Emit top-level description of module, including target triple, inline asm,
-// descriptors for global variables, and function prototype info.
-static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
- BitstreamWriter &Stream) {
+/// Write a record that will eventually hold the word offset of the
+/// module-level VST. For now the offset is 0, which will be backpatched
+/// after the real VST is written. Returns the bit offset to backpatch.
+static uint64_t WriteValueSymbolTableForwardDecl(const ValueSymbolTable &VST,
+ BitstreamWriter &Stream) {
+ if (VST.empty()) return 0;
+
+ // Write a placeholder value in for the offset of the real VST,
+ // which is written after the function blocks so that it can include
+ // the offset of each function. The placeholder offset will be
+ // updated when the real VST is written.
+ BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+ Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_VSTOFFSET));
+ // Blocks are 32-bit aligned, so we can use a 32-bit word offset to
+ // hold the real VST offset. Must use fixed instead of VBR as we don't
+ // know how many VBR chunks to reserve ahead of time.
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
+ unsigned VSTOffsetAbbrev = Stream.EmitAbbrev(Abbv);
+
+ // Emit the placeholder
+ ArrayRef<unsigned> Vals = {llvm::bitc::MODULE_CODE_VSTOFFSET, 0};
+ Stream.EmitRecordWithAbbrev(VSTOffsetAbbrev, Vals);
+
+ // Compute and return the bit offset to the placeholder, which will be
+ // patched when the real VST is written. We can simply subtract the 32-bit
+ // fixed size from the current bit number to get the location to backpatch.
+ return Stream.GetCurrentBitNo() - 32;
+}
+
+/// Emit top-level description of module, including target triple, inline asm,
+/// descriptors for global variables, and function prototype info.
+/// Returns the bit offset to backpatch with the location of the real VST.
+static uint64_t WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
+ BitstreamWriter &Stream) {
// Emit various pieces of data attached to a module.
if (!M->getTargetTriple().empty())
WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
Vals.clear();
}
+
+ uint64_t VSTOffsetPlaceholder =
+ WriteValueSymbolTableForwardDecl(M->getValueSymbolTable(), Stream);
+ return VSTOffsetPlaceholder;
}
static uint64_t GetOptimizationFlags(const Value *V) {
return SE_Fixed7;
}
-// Emit names for globals/functions etc.
-static void WriteValueSymbolTable(const ValueSymbolTable &VST,
- const ValueEnumerator &VE,
- BitstreamWriter &Stream) {
- if (VST.empty()) return;
+/// Emit names for globals/functions etc. The VSTOffsetPlaceholder,
+/// BitcodeStartBit and FunctionIndex are only passed for the module-level
+/// VST, where we are including a function bitcode index and need to
+/// backpatch the VST forward declaration record.
+static void WriteValueSymbolTable(
+ const ValueSymbolTable &VST, const ValueEnumerator &VE,
+ BitstreamWriter &Stream, uint64_t VSTOffsetPlaceholder = 0,
+ uint64_t BitcodeStartBit = 0,
+ DenseMap<const Function *, uint64_t> *FunctionIndex = nullptr) {
+ if (VST.empty()) {
+ // WriteValueSymbolTableForwardDecl should have returned early as
+ // well. Ensure this handling remains in sync by asserting that
+ // the placeholder offset is not set.
+ assert(VSTOffsetPlaceholder == 0);
+ return;
+ }
+
+ if (VSTOffsetPlaceholder > 0) {
+ // Get the offset of the VST we are writing, and backpatch it into
+ // the VST forward declaration record.
+ uint64_t VSTOffset = Stream.GetCurrentBitNo();
+ // The BitcodeStartBit was the stream offset of the actual bitcode
+ // (e.g. excluding any initial darwin header).
+ VSTOffset -= BitcodeStartBit;
+ assert((VSTOffset & 31) == 0 && "VST block not 32-bit aligned");
+ Stream.BackpatchWord(VSTOffsetPlaceholder, VSTOffset / 32);
+ }
+
Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
+ // For the module-level VST, add abbrev Ids for the VST_CODE_FNENTRY
+ // records, which are not used in the per-function VSTs.
+ unsigned FnEntry8BitAbbrev;
+ unsigned FnEntry7BitAbbrev;
+ unsigned FnEntry6BitAbbrev;
+ if (VSTOffsetPlaceholder > 0) {
+ // 8-bit fixed-width VST_FNENTRY function strings.
+ BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+ Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // funcoffset
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
+ FnEntry8BitAbbrev = Stream.EmitAbbrev(Abbv);
+
+ // 7-bit fixed width VST_FNENTRY function strings.
+ Abbv = new BitCodeAbbrev();
+ Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // funcoffset
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
+ FnEntry7BitAbbrev = Stream.EmitAbbrev(Abbv);
+
+ // 6-bit char6 VST_FNENTRY function strings.
+ Abbv = new BitCodeAbbrev();
+ Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // funcoffset
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+ Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
+ FnEntry6BitAbbrev = Stream.EmitAbbrev(Abbv);
+ }
+
// FIXME: Set up the abbrev, we know how many values there are!
// FIXME: We know if the type names can use 7-bit ascii.
SmallVector<unsigned, 64> NameVals;
for (const ValueName &Name : VST) {
-
// Figure out the encoding to use for the name.
StringEncoding Bits =
getStringEncoding(Name.getKeyData(), Name.getKeyLength());
unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
+ NameVals.push_back(VE.getValueID(Name.getValue()));
+
+ Function *F = dyn_cast<Function>(Name.getValue());
+ if (!F) {
+ // If value is an alias, need to get the aliased base object to
+ // see if it is a function.
+ auto *GA = dyn_cast<GlobalAlias>(Name.getValue());
+ if (GA && GA->getBaseObject())
+ F = dyn_cast<Function>(GA->getBaseObject());
+ }
// VST_ENTRY: [valueid, namechar x N]
+ // VST_FNENTRY: [valueid, funcoffset, namechar x N]
// VST_BBENTRY: [bbid, namechar x N]
unsigned Code;
if (isa<BasicBlock>(Name.getValue())) {
Code = bitc::VST_CODE_BBENTRY;
if (Bits == SE_Char6)
AbbrevToUse = VST_BBENTRY_6_ABBREV;
+ } else if (F && !F->isDeclaration()) {
+ // Must be the module-level VST, where we pass in the Index and
+ // have a VSTOffsetPlaceholder. The function-level VST should not
+ // contain any Function symbols.
+ assert(FunctionIndex);
+ assert(VSTOffsetPlaceholder > 0);
+
+ // Save the word offset of the function (from the start of the
+ // actual bitcode written to the stream).
+ assert(FunctionIndex->count(F) == 1);
+ uint64_t BitcodeIndex = (*FunctionIndex)[F] - BitcodeStartBit;
+ assert((BitcodeIndex & 31) == 0 && "function block not 32-bit aligned");
+ NameVals.push_back(BitcodeIndex / 32);
+
+ Code = bitc::VST_CODE_FNENTRY;
+ AbbrevToUse = FnEntry8BitAbbrev;
+ if (Bits == SE_Char6)
+ AbbrevToUse = FnEntry6BitAbbrev;
+ else if (Bits == SE_Fixed7)
+ AbbrevToUse = FnEntry7BitAbbrev;
} else {
Code = bitc::VST_CODE_ENTRY;
if (Bits == SE_Char6)
AbbrevToUse = VST_ENTRY_7_ABBREV;
}
- NameVals.push_back(VE.getValueID(Name.getValue()));
for (const char *P = Name.getKeyData(),
*E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
NameVals.push_back((unsigned char)*P);
/// WriteFunction - Emit a function body to the module stream.
static void WriteFunction(const Function &F, ValueEnumerator &VE,
- BitstreamWriter &Stream) {
+ BitstreamWriter &Stream,
+ DenseMap<const Function *, uint64_t> &FunctionIndex) {
+ // Save the bitcode index of the start of this function block for recording
+ // in the VST.
+ uint64_t BitcodeIndex = Stream.GetCurrentBitNo();
+ FunctionIndex[&F] = BitcodeIndex;
+
Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
VE.incorporateFunction(F);
/// WriteModule - Emit the specified module to the bitstream.
static void WriteModule(const Module *M, BitstreamWriter &Stream,
- bool ShouldPreserveUseListOrder) {
+ bool ShouldPreserveUseListOrder,
+ uint64_t BitcodeStartBit) {
Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
SmallVector<unsigned, 1> Vals;
// Emit top-level description of module, including target triple, inline asm,
// descriptors for global variables, and function prototype info.
- WriteModuleInfo(M, VE, Stream);
+ uint64_t VSTOffsetPlaceholder = WriteModuleInfo(M, VE, Stream);
// Emit constants.
WriteModuleConstants(VE, Stream);
// Emit metadata.
WriteModuleMetadataStore(M, Stream);
- // Emit names for globals/functions etc.
- WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
-
// Emit module-level use-lists.
if (VE.shouldPreserveUseListOrder())
WriteUseListBlock(nullptr, VE, Stream);
// Emit function bodies.
+ DenseMap<const Function *, uint64_t> FunctionIndex;
for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
if (!F->isDeclaration())
- WriteFunction(*F, VE, Stream);
+ WriteFunction(*F, VE, Stream, FunctionIndex);
+
+ WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream,
+ VSTOffsetPlaceholder, BitcodeStartBit, &FunctionIndex);
Stream.ExitBlock();
}
// Emit the module into the buffer.
{
BitstreamWriter Stream(Buffer);
+ // Save the start bit of the actual bitcode, in case there is space
+ // saved at the start for the darwin header above. The reader stream
+ // will start at the bitcode, and we need the offset of the VST
+ // to line up.
+ uint64_t BitcodeStartBit = Stream.GetCurrentBitNo();
// Emit the file header.
Stream.Emit((unsigned)'B', 8);
Stream.Emit(0xD, 4);
// Emit the module.
- WriteModule(M, Stream, ShouldPreserveUseListOrder);
+ WriteModule(M, Stream, ShouldPreserveUseListOrder, BitcodeStartBit);
}
if (TT.isOSDarwin())
projects / oota-llvm.git / blobdiff