[PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.
Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.
Motivation
----------
Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.
We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.
Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.
http://reviews.llvm.org/D19034
<rdar://problem/25256815>
llvm-svn: 266446
diff --git a/llvm/lib/IR/LLVMContextImpl.h b/llvm/lib/IR/LLVMContextImpl.h
index d82ec8d..bd34ac2 100644
--- a/llvm/lib/IR/LLVMContextImpl.h
+++ b/llvm/lib/IR/LLVMContextImpl.h
@@ -480,6 +480,7 @@
unsigned VirtualIndex;
unsigned Flags;
bool IsOptimized;
+ Metadata *Unit;
Metadata *TemplateParams;
Metadata *Declaration;
Metadata *Variables;
@@ -489,14 +490,14 @@
bool IsLocalToUnit, bool IsDefinition, unsigned ScopeLine,
Metadata *ContainingType, unsigned Virtuality,
unsigned VirtualIndex, unsigned Flags, bool IsOptimized,
- Metadata *TemplateParams, Metadata *Declaration,
+ Metadata *Unit, Metadata *TemplateParams, Metadata *Declaration,
Metadata *Variables)
: Scope(Scope), Name(Name), LinkageName(LinkageName), File(File),
Line(Line), Type(Type), IsLocalToUnit(IsLocalToUnit),
IsDefinition(IsDefinition), ScopeLine(ScopeLine),
ContainingType(ContainingType), Virtuality(Virtuality),
VirtualIndex(VirtualIndex), Flags(Flags), IsOptimized(IsOptimized),
- TemplateParams(TemplateParams), Declaration(Declaration),
+ Unit(Unit), TemplateParams(TemplateParams), Declaration(Declaration),
Variables(Variables) {}
MDNodeKeyImpl(const DISubprogram *N)
: Scope(N->getRawScope()), Name(N->getRawName()),
@@ -506,7 +507,7 @@
ScopeLine(N->getScopeLine()), ContainingType(N->getRawContainingType()),
Virtuality(N->getVirtuality()), VirtualIndex(N->getVirtualIndex()),
Flags(N->getFlags()), IsOptimized(N->isOptimized()),
- TemplateParams(N->getRawTemplateParams()),
+ Unit(N->getRawUnit()), TemplateParams(N->getRawTemplateParams()),
Declaration(N->getRawDeclaration()), Variables(N->getRawVariables()) {}
bool isKeyOf(const DISubprogram *RHS) const {
@@ -519,7 +520,7 @@
ContainingType == RHS->getRawContainingType() &&
Virtuality == RHS->getVirtuality() &&
VirtualIndex == RHS->getVirtualIndex() && Flags == RHS->getFlags() &&
- IsOptimized == RHS->isOptimized() &&
+ IsOptimized == RHS->isOptimized() && Unit == RHS->getUnit() &&
TemplateParams == RHS->getRawTemplateParams() &&
Declaration == RHS->getRawDeclaration() &&
Variables == RHS->getRawVariables();