[all-commits] [llvm/llvm-project] be66cf: [DebugInfo] Read CIE pointer as a relocatable value.

[Igor Kudrin via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: be66cf221bbe6bb119d478e69fd2ca21872e2ad3
      https://github.com/llvm/llvm-project/commit/be66cf221bbe6bb119d478e69fd2ca21872e2ad3
  Author: Igor Kudrin <ikudrin at accesssoftek.com>
  Date:   2020-02-20 (Thu, 20 Feb 2020)

  Changed paths:
    M llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
    A llvm/test/DebugInfo/debug-frame-cie-pointer-reloc.test

  Log Message:
  -----------
  [DebugInfo] Read CIE pointer as a relocatable value.

The CIE pointer field of an FDE record contains an offset to
a corresponding CIE record. In object files, this value comes with
relocation because the value has to be fixed when a linker combines
the final section from multiple sources. In most object files there is
only one CIE record at offset 0 of the .debug_frame section, so reading
a relocated or a raw value makes no difference. However, in partially
linked object files there are multiple CIE records and the relocations
should be applied to recover the right offset value.

Differential Revision: https://reviews.llvm.org/D74612


  Commit: 95a239be5b771614a3be47db55ff5ce4acd69390
      https://github.com/llvm/llvm-project/commit/95a239be5b771614a3be47db55ff5ce4acd69390
  Author: Igor Kudrin <ikudrin at accesssoftek.com>
  Date:   2020-02-20 (Thu, 20 Feb 2020)

  Changed paths:
    M llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h

  Log Message:
  -----------
  [DebugInfo] Remove a misleading comment for llvm::dwarf::FDE.

The comment described a linked CIE to be acquired lazily.
That is not true and looks like it was never true.

Differential Revision: https://reviews.llvm.org/D74761


Compare: https://github.com/llvm/llvm-project/compare/8ea3eb86d65f...95a239be5b77