…te module file for C++20 modules instead of PCHGenerator
Previously we're re-using PCHGenerator to generate the module file for
C++20 modules. But this is slighty more or less odd. This patch tries to
use a new class 'CXX20ModulesGenerator' to generate the module file for
C++20 modules.
and "[NFC] [C++20] [Modules] Use new class CXX20ModulesGenerator to
generate module file for C++20 modules instead of PCHGenerator"
This reverts commit fb21343473e33e9a886b42d2fe95d1cec1cd0030.
and commit 18268ac0f48d93c2bcddb69732761971669c09ab.
It looks like there are some problems about linking the compiler
Previously we're re-using PCHGenerator to generate the module file for
C++20 modules. But this is slighty more or less odd. This patch tries
to use a new class 'CXX20ModulesGenerator' to generate the module file
for C++20 modules.
Close https://github.com/llvm/llvm-project/issues/71034
See
https://discourse.llvm.org/t/rfc-c-20-modules-introduce-thin-bmi-and-decls-hash/74755
This patch introduces reduced BMI, which doesn't contain the definitions
of functions and variables if its definitions won't contribute to the
ABI.
Testing is a big part of the patch. We want to make sure the reduced BMI
contains the same behavior with the existing and relatively stable
fatBMI. This is pretty helpful for further reduction.
The user interfaces part it left to following patches to ease the
reviewing.
in filesystems
It is simpler to search for module unit by -fprebuilt-module-path
option. However, the separator ':' of partitions is not friendly.
According to the discussion in https://reviews.llvm.org/D118586, I think
we get consensus to use '-' as the separator instead. The '-' is the
choice of GCC too.
Previously I thought it would be better to add an option. But I feel it
is over-engineering now. Another reason here is that there are too many
options for modules (for clang module mainly) now. Given it is not bad
to use '-' when searching, I think it is acceptable to not add an
option.
Reviewed By: iains
Differential Revision: https://reviews.llvm.org/D120874
