6 Commits

Author SHA1 Message Date
Rafael Espindola
94aac821b6 Remove getRelocationAddress.
Originally added in r139314.

Back then it didn't actually get the address, it got whatever value the
relocation used: address or offset.

The values in different object formats are:

* MachO: Always an offset.
* COFF: Always an address, but when talking about the virtual address of
  sections it says: "for simplicity, compilers should set this to zero".
* ELF: An offset for .o files and and address for .so files. In the case of the
  .so, the relocation in not linked to any section (sh_info is 0). We can't
  really compute an offset.

Some API mappings would be:

* Use getAddress for everything. It would be quite cumbersome. To compute the
  address elf has to follow sh_info, which can be corrupted and therefore the
  method has to return an ErrorOr. The address of the section is also the same
  for every relocation in a section, so we shouldn't have to check the error
  and fetch the value for every relocation.

* Use a getValue and make it up to the user to know what it is getting.

* Use a getOffset and:
 * Assert for dynamic ELF objects. That is a very peculiar case and it is
   probably fair to ask any tool that wants to support it to use ELF.h. The
   only tool we have that reads those (llvm-readobj) already does that. The
   only other use case I can think of is a dynamic linker.
 * Check that COFF .obj files have sections with zero virtual address spaces. If
   it turns out that some assembler/compiler produces these, we can change
   COFFObjectFile::getRelocationOffset to subtract it. Given COFF format,
   this can be done without the need for ErrorOr.

The getRelocationAddress method was never implemented for COFF. It also
had exactly one use in a very peculiar case: a shortcut for adding the
section value to a pcrel reloc on MachO.

Given that, I don't expect that there is any use out there of the C API. If
that is not the case, let me know and I will add it back with the implementation
inlined and do a proper deprecation.

llvm-svn: 241450
2015-07-06 14:55:37 +00:00
Anders Waldenborg
f342831239 [python] Fix getting section contents.
The returnvalue was handled as c_char_p which ment that ctypes
handled it as a NUL-terminated string making it cut the contents
at first NUL (or even worse - overrunning the buffer if it doesn't
contain a NUL).

Differential Revision: http://reviews.llvm.org/D3474

llvm-svn: 207199
2014-04-25 06:25:15 +00:00
Rafael Espindola
56c64fd6fd Convert getFileOffset to getOffset and move it to its only user.
We normally don't drop functions from the C API's, but in this case I think we
can:

* The old implementation of getFileOffset was fairly broken
* The introduction of LLVMGetSymbolFileOffset was itself a C api breaking
  change as it removed LLVMGetSymbolOffset.
* It is an incredibly specialized use case. The only reason MCJIT needs it is
  because of its odd position of being a dynamic linker of .o files.

llvm-svn: 206750
2014-04-21 13:45:32 +00:00
Gregory Szorc
4c739d029b [llvm.py] Implement interface to object files
It is now possible to load object files and scan over sections, symbols,
and relocations! Includes test code with partial coverage.

llvm-svn: 152482
2012-03-10 04:41:24 +00:00
Gregory Szorc
5348ea33df [llvm.py] Make ObjectFile destructor work
Previous code had a double free in MemoryBuffer. The tests now pass.

llvm-svn: 152422
2012-03-09 18:56:33 +00:00
Gregory Szorc
3c13620c0e [llvm.py] Initial skeleton for Python LLVM bindings
This contains a semi-functional skeleton for the implementation of the
LLVM bindings for Python.

The API for the Object.h interface is roughly designed but not
implemented. MemoryBufferRef is implemented and actually appears to
work!

The ObjectFile unit test fails with a segmentation fault because the
LLVM library isn't being properly initialized. The build system doesn't
know about this code yet, so no alerts should fire.

llvm-svn: 152397
2012-03-09 09:07:35 +00:00