Properly set weak flag to COMDAT symbols so that no duplicate definition error will be generated. There is an inaccuracy in setting plain weak for largest selection type, which will be dealt with soon when largest type is properly implemented.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D129764
Adds initial COFF support in JITLink. This is able to run a hello world c program in x86 windows successfully.
Implemented
- COFF object loader
- Static local symbols
- Absolute symbols
- External symbols
- Weak external symbols
- Common symbols
- COFF jitlink-check support
- All COMDAT selection type execpt largest
- Implicit symobl size calculation
- Rel32 relocation with PLT stub.
- IMAGE_REL_AMD64_ADDR32NB relocation
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D128968
Also moves object interface building functions out of Mangling.h and in to the
new ObjectFileInterfaces.h header, and updates the llvm-jitlink tool to use
custom object interfaces rather than a custom link layer.
ObjectLayer::add overloads are added to match the old signatures (which
do not take a MaterializationUnit::Interface). These overloads use the
standard getObjectFileInterface function to build an interface.
Passing a MaterializationUnit::Interface explicitly makes it easier to alter
the effective interface of the object file being added, e.g. by changing symbol
visibility/linkage, or renaming symbols (in both cases the changes will need to
be mirrored by a JITLink pass at link time to update the LinkGraph to match the
explicit interface). Altering interfaces in this way can be useful when lazily
compiling (e.g. for renaming function bodies) or emulating linker options (e.g.
demoting all symbols to hidden visibility to emulate -load_hidden).
Sunho Kim