[PATCH v5 0/8] BaseTools: add support for GCC5 in LTO mode


Ard Biesheuvel
 

This v5 to introduce GCC5 is now a 8 piece series, including some
preparatory cleanup patches that allow all GCC4x and CLANG35 toolchains
to switch to using 'gcc' as the linker. This allows us to get rid of
the wrapper script to marshall ld arguments in order to make them
understandable by gcc, which is fragile and likely to cause problems in
the future.

Since there appears to be a natural split between the 'legacy' GCC
toolchains UNIXGCC, ELFGCC, and CYGGCC[xASL], both in term of supported
architectures [IA32, X64, IPF] vs [IA32, X64, ARM, AARCH64], and in
terms of maintenance, these toolchains are not moved to using 'gcc' as
the linker, and instead, a new BUILDRULEFAMILY is introduced called GCCLD
that will retain the old behavior.

The result is that GCC5 can align much more closely with its predecessors,
making the expected maintenance burden of supporting GCC back to v4.4
much lower.

Changes since v4:
- added patch to use 'protected' visibility only for the libraries that
define the module entry points (_ModuleEntryPoint), to prevent them from
being optimized away by the LTO routines
- added Jordan's ack/RBs
- add some extra comments to tools_def.template (#8)

Changes since v3:
- like Steven does in his GCC5LTO patch, add -fno-builtin to IA32 and X64
CC_FLAGS; this addresses a build issue reported by Liming
- add -Os the the linker flags as well, for AARCH64 this does not seem to make
a difference, but it is arguably correct since the LTO processing at link
time involves code generation as well
- add Laszlo's ack to #2
- new patch #6 to omit the autogenerated build-id from the PE/COFF binary

Changes since v2:
- add license headers to LTO glue files for ARM and AARCH64 (#5)
- get rid of lto-ld-wrapper script

Ard Biesheuvel (8):
BaseTools CLANG35: drop problematic use-movt and save-temps options
ArmVirtPkg/ArmVirtPrePiUniCoreRelocatable: ignore .hash and .note
sections
BaseTools UNIXGCC ELFGCC CYGGCC: clone GCC build rule family into
GCCLD
BaseTools GCC: use 'gcc' as the linker command for GCC44 and later
ArmPkg: add prebuilt glue binaries for GCC5 LTO support
BaseTools GCC: drop GNU notes section from EFI image
MdePkg GCC/X64: avoid 'hidden' visibility for module entry points
BaseTools GCC: introduce GCC5 toolchain to support GCC v5.x in LTO
mode

ArmPkg/GccLto/liblto-aarch64.a | Bin 0 -> 1016 bytes
ArmPkg/GccLto/liblto-aarch64.s | 27 ++
ArmPkg/GccLto/liblto-arm.a | Bin 0 -> 2096 bytes
ArmPkg/GccLto/liblto-arm.s | 61 ++++
ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf | 2 +-
ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds | 3 +
BaseTools/Conf/build_rule.template | 31 +-
BaseTools/Conf/tools_def.template | 350 +++++++++++++++-----
BaseTools/Scripts/GccBase.lds | 6 +
EmulatorPkg/Unix/Host/Host.inf | 6 +-
MdePkg/Include/X64/ProcessorBind.h | 9 +-
MdePkg/Library/DxeCoreEntryPoint/DxeCoreEntryPoint.inf | 2 +
MdePkg/Library/PeiCoreEntryPoint/PeiCoreEntryPoint.inf | 2 +
MdePkg/Library/PeimEntryPoint/PeimEntryPoint.inf | 2 +
MdePkg/Library/UefiApplicationEntryPoint/UefiApplicationEntryPoint.inf | 2 +
MdePkg/Library/UefiDriverEntryPoint/UefiDriverEntryPoint.inf | 2 +
16 files changed, 396 insertions(+), 109 deletions(-)
create mode 100644 ArmPkg/GccLto/liblto-aarch64.a
create mode 100644 ArmPkg/GccLto/liblto-aarch64.s
create mode 100644 ArmPkg/GccLto/liblto-arm.a
create mode 100644 ArmPkg/GccLto/liblto-arm.s

--
2.7.4

Join devel@edk2.groups.io to automatically receive all group messages.