Add -fpch-instantiate-templates which makes template instantiations be
performed already in the PCH instead of it being done in every single
file that uses the PCH (but every single file will still do it as well
in order to handle its own instantiations). I can see 20-30% build
time saved with the few tests I've tried.
The change may reorder compiler output and also generated code, but
should be generally safe and produce functionally identical code.
There are some rare cases that do not compile with it,
such as test/PCH/pch-instantiate-templates-forward-decl.cpp. If
template instantiation bailed out instead of reporting the error,
these instantiations could even be postponed, which would make them
work.
Enable this by default for clang-cl. MSVC creates PCHs by compiling
them using an empty .cpp file, which means templates are instantiated
while building the PCH and so the .h needs to be self-contained,
making test/PCH/pch-instantiate-templates-forward-decl.cpp to fail
with MSVC anyway. So the option being enabled for clang-cl matches this.
Differential Revision: https://reviews.llvm.org/D69585
This patch adds ObjectFilePCHContainerOperations uses the LLVM backend
to put the contents of a PCH into a __clangast section inside a COFF, ELF,
or Mach-O object file container.
This is done to facilitate module debugging by makeing it possible to
store the debug info for the types defined by a module alongside the AST.
rdar://problem/20091852
llvm-svn: 241620
This is a necessary prerequisite for debugging with modules.
The .pcm files become containers that hold the serialized AST which allows
us to store debug information in the module file that can be shared by all
object files that were built importing the module.
This reapplies r230044 with a fixed configure+make build and updated
dependencies and testcase requirements. Over the last iteration this
version adds
- missing target requirements for testcases that specify an x86 triple,
- a missing clangCodeGen.a dependency to libClang.a in the make build.
rdar://problem/19104245
llvm-svn: 230423
This triggered a miscompilation of code using Boost's function_template.hpp
when it was included inside a PCH file. A local static within
that header would be treated as local extern, resulting in the wrong
mangling. This only occurred during PCH deserialization.
Fixes <rdar://problem/15975816> and <rdar://problem/15926311>.
llvm-svn: 201130
Luboš Luňák