Commit Graph

5 Commits

Author SHA1 Message Date
Oliver Stannard
bb804ee909 Emit DWARF3 call frame information when DWARF3+ debug info is requested
Currently, llvm always emits a DWARF CIE with a version of 1, even when emitting
DWARF 3 or 4, which both support CIE version 3. This patch makes it emit the
newer CIE version when we are emitting DWARF 3 or 4. This will not reduce
compatibility, as we already emit other DWARF3/4 features, and is worth doing as
the DWARF3 spec removed some ambiguities in the interpretation of call frame
information.

It also fixes a minor bug where the "return address" field of the CIE was
encoded as a ULEB128, which is only valid when the CIE version is 3. There are
no test changes for this, because (as far as I can tell) none of the platforms
that we test have a return address register with a DWARF register number >127.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211272 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 15:39:33 +00:00
Rafael Espindola
7486d92a6c 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182908 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-30 03:05:14 +00:00
Rafael Espindola
d787a41b11 Implement the "mips endian" for r_info.
Normally r_info is just a 32 of 64 bit number matching the endian of the rest
of the file. Unfortunately, mips 64 bit little endian is special: The top 32
bits are a little endian number and the following 32 are a big endian one.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178694 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 21:02:51 +00:00
Rafael Espindola
04011e8429 Fix the fde encoding used by mips to match gas.
This finally fixes the encoding. The patch also
* Removes eh-frame.ll. It was an unnecessary .ll to .o test that was checking
  the wrong value.
* Merge fde-reloc.s and eh-frame.s into a single test, since the only difference
  was the run lines.
* Don't blindly test the content of the entire .eh_frame section. It makes it
  hard to anyone actually fixing a bug and hitting a difference in a binary
  blob. Instead, use a CHECK for each field and document what is being checked.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178615 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 03:13:19 +00:00
Jack Carter
732f4bc7c4 Mips direct object exception handling regression
Revision 177141 caused a regression in all but
mips64 little endian. That is because none of the
other Mips targets had test cases checking the 
contents of the .eh_frame section. This patch fixes
both the llvm code and adds an assembler test case 
to include the current 4 flavors.

The test cases unfortunately rely on llvm-objdump. A
preferable method would be to use a pretty printer output
such as what readelf -wf <elf_file> would give.

I also changed the name of the test case to correct a typo.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178506 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 21:55:15 +00:00