Commit Graph

4 Commits

Author SHA1 Message Date
Rafael Espindola f44db24e1f Avoid explicit relocation sorting most of the time.
These days relocations are created and stored in a deterministic way.
The order they are created is also suitable for the .o file, so we don't
need an explicit sort.

The last remaining exception is MIPS.

llvm-svn: 255902
2015-12-17 16:22:06 +00:00
Rafael Espindola 88d1f632cf Write the section header string table directly to the output stream.
Instead of accumulating the content in a fragment first, just write it
to the output stream.

Also put it first in the section table, so that we never have to worry
about its index being >= SHN_LORESERVE.

llvm-svn: 236145
2015-04-29 20:25:24 +00:00
Rafael Espindola 4f60a38f18 Change how we iterate over relocations on ELF.
For COFF and MachO, sections semantically have relocations that apply to them.
That is not the case on ELF.

In relocatable objects (.o), a section with relocations in ELF has offsets to
another section where the relocations should be applied.

In dynamic objects and executables, relocations don't have an offset, they have
a virtual address. The section sh_info may or may not point to another section,
but that is not actually used for resolving the relocations.

This patch exposes that in the ObjectFile API. It has the following advantages:

* Most (all?) clients can handle this more efficiently. They will normally walk
all relocations, so doing an effort to iterate in a particular order doesn't
save time.

* llvm-readobj now prints relocations in the same way the native readelf does.

* probably most important, relocations that don't point to any section are now
visible. This is the case of relocations in the rela.dyn section. See the
updated relocation-executable.test for example.

llvm-svn: 182908
2013-05-30 03:05:14 +00:00
Logan Chien 4ea23b56c5 Implement AsmParser for ARM unwind directives.
This commit implements the AsmParser for fnstart, fnend,
cantunwind, personality, handlerdata, pad, setfp, save, and
vsave directives.

This commit fixes some minor issue in the ARMELFStreamer:

* The switch back to corresponding section after the .fnend
  directive.

* Emit the unwind opcode while processing .fnend directive
  if there is no .handlerdata directive.

* Emit the unwind opcode to .ARM.extab while processing
  .handlerdata even if .personality directive does not exist.

llvm-svn: 181603
2013-05-10 16:17:24 +00:00