[0/3] Further libgcc unwinder improvements

Message ID cover.1667930077.git.fweimer@redhat.com
Series Further libgcc unwinder improvements |


Florian Weimer Nov. 8, 2022, 6:05 p.m. UTC
  This series makes some further unwinder improvements.  Unfortunately,
not many targets define __LIBGCC_DWARF_REG_SIZES_CONSTANT__; x86-64
does, and it makes uw_install_context_1 quite a bit faster because GCC
no longer has to emit generic memcpy code for it.  In general, it may be
worthwhile to replace this code with target-specific implementations.

Tested on powerpc64le-linux-gnu, x86_64-linux-gnu; I didn't see any test
result differences.  Built GCC for msp430-elf, too.

The revision for the patch I posted earlier (using SWAR techniques for
get_cie_encoding) is not ready yet and probably won't make GCC 13.  It
requires some header cleanups first.


Florian Weimer (3):
  Compute a table of DWARF register sizes at compile
  Define __LIBGCC_DWARF_REG_SIZES_CONSTANT__ if DWARF register size is
  libgcc: Specialize execute_cfa_program in DWARF unwinder for

 gcc/c-family/c-cppbuiltin.cc    |   8 +
 gcc/config/msp430/msp430.cc     |  11 +-
 gcc/config/rs6000/rs6000.cc     |  14 +-
 gcc/debug.h                     |   2 +
 gcc/doc/tm.texi                 |   7 +-
 gcc/dwarf2cfi.cc                | 116 +++++-----
 gcc/target.def                  |   8 +-
 libgcc/unwind-dw2-execute_cfa.h | 322 ++++++++++++++++++++++++++++
 libgcc/unwind-dw2.c             | 360 ++++++--------------------------
 9 files changed, 472 insertions(+), 376 deletions(-)
 create mode 100644 libgcc/unwind-dw2-execute_cfa.h

base-commit: 5d060d8b0477ff4911f41c816281daaa24b41a13