Turn DISubprogram into a variable-length node.
DISubprogram currently has 10 pointer operands, several of which are
often nullptr. This patch reduces the amount of memory allocated by
DISubprogram by rearranging the operands such that containing type,
template params, and thrown types come last, and are only allocated
when they are non-null (or followed by non-null operands).
This patch also eliminates the entirely unused DisplayName operand.
This saves up to 4 pointer operands per DISubprogram. (I tried
measuring the effect on peak memory usage on an LTO link of an X86
llc, but the results were very noisy).
This reapplies r301498 with an attempted workaround for g++.
Differential Revision: https://reviews.llvm.org/D32560
llvm-svn: 301501
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index 498617c..3db9a3d 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -214,6 +214,10 @@
#define DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(CLASS, OPS) \
return storeImpl(new (array_lengthof(OPS)) CLASS(Context, Storage, OPS), \
Storage, Context.pImpl->CLASS##s)
+#define DEFINE_GETIMPL_STORE_N(CLASS, ARGS, OPS, NUM_OPS) \
+ return storeImpl(new (NUM_OPS) \
+ CLASS(Context, Storage, UNWRAP_ARGS(ARGS), OPS), \
+ Storage, Context.pImpl->CLASS##s)
DISubrange *DISubrange::getImpl(LLVMContext &Context, int64_t Count, int64_t Lo,
StorageType Storage, bool ShouldCreate) {
@@ -449,13 +453,22 @@
IsDefinition, ScopeLine, ContainingType, Virtuality,
VirtualIndex, ThisAdjustment, Flags, IsOptimized, Unit,
TemplateParams, Declaration, Variables, ThrownTypes));
- Metadata *Ops[] = {File, Scope, Name, Name,
- LinkageName, Type, ContainingType, Unit,
- TemplateParams, Declaration, Variables, ThrownTypes};
- DEFINE_GETIMPL_STORE(DISubprogram, (Line, ScopeLine, Virtuality, VirtualIndex,
- ThisAdjustment, Flags, IsLocalToUnit,
- IsDefinition, IsOptimized),
- Ops);
+ SmallVector<Metadata *, 11> Ops = {
+ File, Scope, Name, LinkageName, Type, Unit,
+ Declaration, Variables, ContainingType, TemplateParams, ThrownTypes};
+ if (!ThrownTypes) {
+ Ops.pop_back();
+ if (!TemplateParams) {
+ Ops.pop_back();
+ if (!ContainingType)
+ Ops.pop_back();
+ }
+ }
+ DEFINE_GETIMPL_STORE_N(DISubprogram,
+ (Line, ScopeLine, Virtuality, VirtualIndex,
+ ThisAdjustment, Flags, IsLocalToUnit, IsDefinition,
+ IsOptimized),
+ Ops, Ops.size());
}
bool DISubprogram::describes(const Function *F) const {