Bitcode: Add METADATA_NODE and METADATA_VALUE
This reflects the typelessness of `Metadata` in the bitcode format,
removing types from all metadata operands.
`METADATA_VALUE` represents a `ValueAsMetadata`, and always has two
fields: the type and the value.
`METADATA_NODE` represents an `MDNode`, and unlike `METADATA_OLD_NODE`,
doesn't store types. It stores operands at their ID+1 so that `0` can
reference `nullptr` operands.
Part of PR21532.
llvm-svn: 224073
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index a92b9c8..4265bf7 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -1166,6 +1166,27 @@
MDValueList.AssignValue(MDNode::get(Context, Elts), NextMDValueNo++);
break;
}
+ case bitc::METADATA_VALUE: {
+ if (Record.size() != 2)
+ return Error(BitcodeError::InvalidRecord);
+
+ Type *Ty = getTypeByID(Record[0]);
+ if (Ty->isMetadataTy() || Ty->isVoidTy())
+ return Error(BitcodeError::InvalidRecord);
+
+ MDValueList.AssignValue(
+ ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
+ NextMDValueNo++);
+ break;
+ }
+ case bitc::METADATA_NODE: {
+ SmallVector<Metadata *, 8> Elts;
+ Elts.reserve(Record.size());
+ for (unsigned ID : Record)
+ Elts.push_back(ID ? MDValueList.getValueFwdRef(ID - 1) : nullptr);
+ MDValueList.AssignValue(MDNode::get(Context, Elts), NextMDValueNo++);
+ break;
+ }
case bitc::METADATA_STRING: {
std::string String(Record.begin(), Record.end());
llvm::UpgradeMDStringConstant(String);
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index f7c29d4..90ac1f1 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -737,33 +737,18 @@
return Flags;
}
-static void WriteValueAsMetadataImpl(const ValueAsMetadata *MD,
- const ValueEnumerator &VE,
- BitstreamWriter &Stream,
- SmallVectorImpl<uint64_t> &Record,
- unsigned Code) {
+static void WriteValueAsMetadata(const ValueAsMetadata *MD,
+ const ValueEnumerator &VE,
+ BitstreamWriter &Stream,
+ SmallVectorImpl<uint64_t> &Record) {
// Mimic an MDNode with a value as one operand.
Value *V = MD->getValue();
Record.push_back(VE.getTypeID(V->getType()));
Record.push_back(VE.getValueID(V));
- Stream.EmitRecord(Code, Record, 0);
+ Stream.EmitRecord(bitc::METADATA_VALUE, Record, 0);
Record.clear();
}
-static void WriteLocalAsMetadata(const LocalAsMetadata *MD,
- const ValueEnumerator &VE,
- BitstreamWriter &Stream,
- SmallVectorImpl<uint64_t> &Record) {
- WriteValueAsMetadataImpl(MD, VE, Stream, Record, bitc::METADATA_OLD_FN_NODE);
-}
-
-static void WriteConstantAsMetadata(const ConstantAsMetadata *MD,
- const ValueEnumerator &VE,
- BitstreamWriter &Stream,
- SmallVectorImpl<uint64_t> &Record) {
- WriteValueAsMetadataImpl(MD, VE, Stream, Record, bitc::METADATA_OLD_NODE);
-}
-
static void WriteMDNode(const MDNode *N,
const ValueEnumerator &VE,
BitstreamWriter &Stream,
@@ -771,20 +756,13 @@
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
Metadata *MD = N->getOperand(i);
if (!MD) {
- Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
Record.push_back(0);
continue;
}
- if (auto *V = dyn_cast<ConstantAsMetadata>(MD)) {
- Record.push_back(VE.getTypeID(V->getValue()->getType()));
- Record.push_back(VE.getValueID(V->getValue()));
- continue;
- }
assert(!isa<LocalAsMetadata>(MD) && "Unexpected function-local metadata");
- Record.push_back(VE.getTypeID(Type::getMetadataTy(N->getContext())));
- Record.push_back(VE.getMetadataID(MD));
+ Record.push_back(VE.getMetadataID(MD) + 1);
}
- Stream.EmitRecord(bitc::METADATA_OLD_NODE, Record, 0);
+ Stream.EmitRecord(bitc::METADATA_NODE, Record);
Record.clear();
}
@@ -807,7 +785,7 @@
Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
StartedMetadataBlock = true;
}
- WriteConstantAsMetadata(MDC, VE, Stream, Record);
+ WriteValueAsMetadata(MDC, VE, Stream, Record);
} else if (const MDString *MDS = dyn_cast<MDString>(MDs[i])) {
if (!StartedMetadataBlock) {
Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
@@ -870,7 +848,7 @@
Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
StartedMetadataBlock = true;
}
- WriteLocalAsMetadata(MDs[i], VE, Stream, Record);
+ WriteValueAsMetadata(MDs[i], VE, Stream, Record);
}
if (StartedMetadataBlock)
diff --git a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
index cae20a8..c90dfbd 100644
--- a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -521,15 +521,9 @@
void ValueEnumerator::EnumerateMDNodeOperands(const MDNode *N) {
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
Metadata *MD = N->getOperand(i);
- if (!MD) {
- EnumerateType(Type::getVoidTy(N->getContext()));
+ if (!MD)
continue;
- }
assert(!isa<LocalAsMetadata>(MD) && "MDNodes cannot be function-local");
- if (auto *C = dyn_cast<ConstantAsMetadata>(MD)) {
- EnumerateValue(C->getValue());
- continue;
- }
EnumerateMetadata(MD);
}
}