This version enhances the previous patch to add root initialization
as discussed here:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070910/053455.html
Collector gives its subclasses control over generic algorithms:
unsigned NeededSafePoints; //< Bitmask of required safe points.
bool CustomReadBarriers; //< Default is to insert loads.
bool CustomWriteBarriers; //< Default is to insert stores.
bool CustomRoots; //< Default is to pass through to backend.
bool InitRoots; //< If set, roots are nulled during lowering.
It also has callbacks which collectors can hook:
/// If any of the actions are set to Custom, this is expected to
/// be overriden to create a transform to lower those actions to
/// LLVM IR.
virtual Pass *createCustomLoweringPass() const;
/// beginAssembly/finishAssembly - Emit module metadata as
/// assembly code.
virtual void beginAssembly(Module &M, std::ostream &OS,
AsmPrinter &AP,
const TargetAsmInfo &TAI) const;
virtual void finishAssembly(Module &M,
CollectorModuleMetadata &CMM,
std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI) const;
Various other independent algorithms could be implemented, but were
not necessary for the initial two collectors. Some examples are
listed here:
http://llvm.org/docs/GarbageCollection.html#collector-algos
llvm-svn: 42466
This motivated implementing a devious clattner inspired solution:-)
This approach uses a small value "Selector" class to point to an IdentifierInfo for the 0/1 case. For multi-keyword selectors, we instantiate a MultiKeywordSelector object (previously known as SelectorInfo). Now, the incremental cost for selectors is only 24,800 for Cocoa.h! This saves 156,592 bytes, or 86%!! The size reduction is also the result of getting rid of the AST slot, which was not strictly necessary (we will associate a selector with it's method using another table...most likely in Sema).
This change was critical to make now, before we have too many clients.
I still need to add some comments to the Selector class...will likely add later today/tomorrow.
llvm-svn: 42452
DeclBitVector
ExprDeclBitVector (which subclasses the former)
DeclBitVector is for analyses that just want to track bitvector state
for declarations.
ExprDeclBitVector is for analyses that want to track bitvector state
for both both declarations and CFGBlock-level expressions.
llvm-svn: 42445
The only generated code difference is that now we call memcpy when
the size of the array is unknown. This matches GCC behavior and is
better since the run time value can be arbitrarily large.
llvm-svn: 42433
taintness across expressions.
Made "smart-culling" of taint propagation (for error reporting)
correctly handle conditional expressions and a few other edge cases.
llvm-svn: 42421
other than PPC64. Instead of fixing it, just remove it and fix all the
places that use it to use TargetData::getPointerSize() instead, as there
aren't very many. Most of the references were in DwarfWriter.cpp.
llvm-svn: 42419
It includes:
- location and of each safe point in machine code (identified by a
label)
- location of each root within the stack frame (identified by an
offset), including the metadata tag provided to llvm.gcroot in
the user program
- size of the stack frame (for collectors which want to cheat on
stack crawling :)
- and eventually will include liveness
It is to be populated by back-ends during code-generation.
CollectorModuleMetadata aggregates this information across the
entire module.
llvm-svn: 42418
Gordon Henriksen