AST file more lazy, so that we don't eagerly load that information for
all known identifiers each time a new AST file is loaded. The eager
reloading made some sense in the context of precompiled headers, since
very few identifiers were defined before PCH load time. With modules,
however, a huge amount of code can get parsed before we see an
@import, so laziness becomes important here.
The approach taken to make this information lazy is fairly simple:
when we load a new AST file, we mark all of the existing identifiers
as being out-of-date. Whenever we want to access information that may
come from an AST (e.g., whether the identifier has a macro definition,
or what top-level declarations have that name), we check the
out-of-date bit and, if it's set, ask the AST reader to update the
IdentifierInfo from the AST files. The update is a merge, and we now
take care to merge declarations before/after imports with declarations
from multiple imports.
The results of this optimization are fairly dramatic. On a small
application that brings in 14 non-trivial modules, this takes modules
from being > 3x slower than a "perfect" PCH file down to 30% slower
for a full rebuild. A partial rebuild (where the PCH file or modules
can be re-used) is down to 7% slower. Making the PCH file just a
little imperfect (e.g., adding two smallish modules used by a bunch of
.m files that aren't in the PCH file) tips the scales in favor of the
modules approach, with 24% faster partial rebuilds.
This is just a first step; the lazy scheme could possibly be improved
by adding versioning, so we don't search into modules we already
searched. Moreover, we'll need similar lazy schemes for all of the
other lookup data structures, such as DeclContexts.
llvm-svn: 143100
This also adds a -Wc++98-compat-pedantic for warning on constructs which would
be diagnosed by -std=c++98 -pedantic (that is, it warns even on C++11 features
which we enable by default, with no warning, in C++98 mode).
llvm-svn: 142034
'id' that can be used (only!) via a contextual keyword as the result
type of an Objective-C message send. 'instancetype' then gives the
method a related result type, which we have already been inferring for
a variety of methods (new, alloc, init, self, retain). Addresses
<rdar://problem/9267640>.
llvm-svn: 139275
Previously we would cut off the source file buffer at the code-completion
point; this impeded code-completion inside C++ inline methods and,
recently, with buffering ObjC methods.
Have the code-completion inserted into the source buffer so that it can
be buffered along with a method body. When we actually hit the code-completion
point the cut-off lexing or parsing.
Fixes rdar://10056932&8319466
llvm-svn: 139086
variants to 'expand'. This changed a couple of public APIs, including
one public type "MacroInstantiation" which is now "MacroExpansion". The
rest of the codebase was updated to reflect this, especially the
libclang code. Two of the C++ (and thus easily changed) libclang APIs
were updated as well because they pertained directly to the old
MacroInstantiation class.
No functionality changed.
llvm-svn: 135139
structure to hold inferred information, then propagate each invididual
bit down to -cc1. Separate the bits of "supports weak" and "has a native
ARC runtime"; make the latter a CodeGenOption.
The tool chain is still driving this decision, because it's the place that
has the required deployment target information on Darwin, but at least it's
better-factored now.
llvm-svn: 134453
Previously macro expanded tokens were added to Preprocessor's bump allocator and never released,
even after the TokenLexer that were lexing them was finished, thus they were wasting memory.
A very "useful" boost library was causing clang to eat 1 GB just for the expanded macro tokens.
Introduce a special cache that works like a stack; a TokenLexer can add the macro expanded tokens
in the cache, and when it finishes, the tokens are removed from the end of the cache.
Now consumed memory by expanded tokens for that library is ~ 1.5 MB.
Part of rdar://9327049.
llvm-svn: 134105
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
minor issues along the way:
- Non-type template parameters of type 'std::nullptr_t' were not
permitted.
- We didn't properly introduce built-in operators for nullptr ==,
!=, <, <=, >=, or > as candidate functions .
To my knowledge, there's only one (minor but annoying) part of nullptr
that hasn't been implemented: catching a thrown 'nullptr' as a pointer
or pointer-to-member, per C++0x [except.handle]p4.
llvm-svn: 131813
__has_extension is a function-like macro which takes the same set
of feature identifiers as __has_feature. It evaluates to 1 if the
feature is supported by Clang in the current language (either as a
language extension or a standard language feature) or 0 if not.
At the same time, add support for the C1X feature identifiers
c_generic_selections (renamed from generic_selections) and
c_static_assert, and document them.
Patch by myself and Jean-Daniel Dupas.
llvm-svn: 131308
As far as I know, this implementation is complete but might be missing a
few optimizations. Exceptions and virtual bases are handled correctly.
Because I'm an optimist, the web page has appropriately been updated. If
I'm wrong, feel free to downgrade its support categories.
llvm-svn: 130642
Dylan Noblesmith