IR: Enable debug info type ODR uniquing for forward decls
Add a new method, DICompositeType::buildODRType, that will create or
mutate the DICompositeType for a given ODR identifier, and use it in
LLParser and BitcodeReader instead of DICompositeType::getODRType.
The logic is as follows:
- If there's no node, create one with the given arguments.
- Else, if the current node is a forward declaration and the new
arguments would create a definition, mutate the node to match the
new arguments.
- Else, return the old node.
This adds a missing feature supported by the current DITypeIdentifierMap
(which I'm slowly making redudant). The only remaining difference is
that the DITypeIdentifierMap has a "the-last-one-wins" rule, whereas
DICompositeType::buildODRType has a "the-first-one-wins" rule.
For now I'm leaving behind DICompositeType::getODRType since it has
obvious, low-level semantics that are convenient for unit testing.
llvm-svn: 266786
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index 37986f7..c2ecd4e 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -255,6 +255,7 @@
bool ShouldCreate) {
assert(isCanonical(Name) && "Expected canonical MDString");
+ // Keep this in sync with buildODRType.
DEFINE_GETIMPL_LOOKUP(
DICompositeType, (Tag, Name, File, Line, Scope, BaseType, SizeInBits,
AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
@@ -266,6 +267,40 @@
Ops);
}
+DICompositeType *DICompositeType::buildODRType(
+ LLVMContext &Context, MDString &Identifier, unsigned Tag, MDString *Name,
+ Metadata *File, unsigned Line, Metadata *Scope, Metadata *BaseType,
+ uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
+ unsigned Flags, Metadata *Elements, unsigned RuntimeLang,
+ Metadata *VTableHolder, Metadata *TemplateParams) {
+ assert(!Identifier.getString().empty() && "Expected valid identifier");
+ if (!Context.isODRUniquingDebugTypes())
+ return nullptr;
+ auto *&CT = (*Context.pImpl->DITypeMap)[&Identifier];
+ if (!CT)
+ return CT = DICompositeType::getDistinct(
+ Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+ AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
+ VTableHolder, TemplateParams, &Identifier);
+
+ // Only mutate CT if it's a forward declaration and the new operands aren't.
+ assert(CT->getRawIdentifier() == &Identifier && "Wrong ODR identifier?");
+ if (!CT->isForwardDecl() || (Flags & DINode::FlagFwdDecl))
+ return CT;
+
+ // Mutate CT in place. Keep this in sync with getImpl.
+ CT->mutate(Tag, Line, RuntimeLang, SizeInBits, AlignInBits, OffsetInBits,
+ Flags);
+ Metadata *Ops[] = {File, Scope, Name, BaseType,
+ Elements, VTableHolder, TemplateParams, &Identifier};
+ assert(std::end(Ops) - std::begin(Ops) == CT->getNumOperands() &&
+ "Mismatched number of operands");
+ for (unsigned I = 0, E = CT->getNumOperands(); I != E; ++I)
+ if (Ops[I] != CT->getOperand(I))
+ CT->setOperand(I, Ops[I]);
+ return CT;
+}
+
DICompositeType *DICompositeType::getODRType(
LLVMContext &Context, MDString &Identifier, unsigned Tag, MDString *Name,
Metadata *File, unsigned Line, Metadata *Scope, Metadata *BaseType,