Commit Graph

6 Commits

Author SHA1 Message Date
Rui Ueyama 3b04d833c4 Set sh_addralign to 1 instead of 0.
ELF spec says that alignment of 0 is equivalent to 1.
Previously, we arbitrary set to 0 or 1, but always setting to 1
makes our program simpler.

llvm-svn: 275374
2016-07-14 05:46:24 +00:00
Rui Ueyama f86cb90a2d Do not propagate section name and attributes to .eh_frame.
.eh_frame is always ".eh_frame" and its attribute is fixed.
No need to copy from inputs to outputs. GNU gold also sets
SHT_PROGBITS.

llvm-svn: 270443
2016-05-23 15:12:41 +00:00
Rui Ueyama 144debcc0f Remove unnecessary trailing semicolons.
Since this semicolon existed in an early test file,
it has spread to many files.

llvm-svn: 267659
2016-04-27 02:58:27 +00:00
George Rimar f6bc65a3b2 Reapply r257753 with fix:
Added check for terminator CIE/FDE which has zero data size.
void EHOutputSection<ELFT>::addSectionAux(
...
 // If CIE/FDE data length is zero then Length is 4, this
 // shall be considered a terminator and processing shall end.
    if (Length == 4)
      break;
...

After this "Bug 25923 - lld/ELF2 linked application crashes if exceptions were used." is fixed for me. Self link of clang also works.

Initial commit message:
[ELF] - implemented --eh-frame-hdr command line option.

--eh-frame-hdr
Request creation of ".eh_frame_hdr" section and ELF "PT_GNU_EH_FRAME" segment header.

Both gold and the GNU linker support an option --eh-frame-hdr which tell them to construct a header for all the .eh_frame sections. This header is placed in a section named .eh_frame_hdr and also in a PT_GNU_EH_FRAME segment. At runtime the unwinder can find all the PT_GNU_EH_FRAME segments by calling dl_iterate_phdr.
This section contains a lookup table for quick binary search of FDEs.
Detailed info can be found here:
http://www.airs.com/blog/archives/462

Differential revision: http://reviews.llvm.org/D15712

llvm-svn: 257889
2016-01-15 13:34:52 +00:00
Rui Ueyama 5f91ace828 Revert r257753: "[ELF] - implemented --eh-frame-hdr command line option."
This reverts commit r257753 because we cannot link Clang with this patch.

llvm-svn: 257797
2016-01-14 20:32:19 +00:00
George Rimar 28f4fbe480 [ELF] - implemented --eh-frame-hdr command line option.
--eh-frame-hdr
Request creation of ".eh_frame_hdr" section and ELF "PT_GNU_EH_FRAME" segment header.

Both gold and the GNU linker support an option --eh-frame-hdr which tell them to construct a header for all the .eh_frame sections. This header is placed in a section named .eh_frame_hdr and also in a PT_GNU_EH_FRAME segment. At runtime the unwinder can find all the PT_GNU_EH_FRAME segments by calling dl_iterate_phdr.
This section contains a lookup table for quick binary search of FDEs.
Detailed info can be found here:
http://www.airs.com/blog/archives/462

Differential revision: http://reviews.llvm.org/D15712

llvm-svn: 257753
2016-01-14 10:30:32 +00:00