identifiers from a precompiled header.
This patch changes the primary name lookup method for entities within
a precompiled header. Previously, we would load all of the names of
declarations at translation unit scope into a large DenseMap (inside
the TranslationUnitDecl's DeclContext), and then perform a special
"last resort" lookup into this DeclContext when we knew there was a
PCH file (see Sema::LookupName). Now, when we see an identifier named
for the first time, we load all of the declarations with that name
that are visible from the translation unit into the IdentifierInfo's
chain of declarations. Thus, the explicit "look into the translation
unit's DeclContext" code is gone, and Sema effectively uses the same
IdentifierInfo-based name lookup mechanism whether we are using a PCH
file or not.
This approach should help PCH scale with the size of the input program
rather than the size of the PCH file. The "Hello, World!" application
with Carbon.h as a PCH file now loads 20% of the identifiers in the
PCH file rather than 85% of the identifiers.
90% of the 20% of identifiers loaded are actually loaded when we
deserialize the preprocessor state. The next step is to make the
preprocessor load macros lazily, which should drastically reduce the
number of types, declarations, and identifiers loaded for "Hello,
World".
llvm-svn: 69737
that also includes the contents of the IdentifierInfo itself (the
various fields and flags, along with the chain of identifiers visible
at the top level that have that name).
We don't make any use of the hash table yet, except that our
identifier ID -> string mapping points into the hash table now.
llvm-svn: 69625
also gets access to the Sema object performing semantic analysis. This
will be used by the PCH writer to serialize Sema state.
No functionality change.
llvm-svn: 69595
AST context's __builtin_va_list type will be set when the PCH file is
loaded. This fixes the crash when CodeGen'ing a va_arg expression
pulled in from a PCH file.
llvm-svn: 69421
lazy PCH deserialization. Propagate that argument wherever it needs to
be. No functionality change, except that I've tightened up a few PCH
tests in preparation.
llvm-svn: 69406
kind PCH handles that has an expression as an operand, so most of this
work is in the infrastructure to rebuild expression trees from the
serialized representation. We now store expressions in post-order
(e.g., Reverse Polish Notation), so that we can easily rebuild the
appropriate expression tree.
llvm-svn: 69101
non-inline external definitions (and tentative definitions) that are
found at the top level. The corresponding declarations are stored in a
record in the PCH file, so that they can be provided to the
ASTConsumer (via HandleTopLevelDecl) when the PCH file is read.
llvm-svn: 69005
buffer generated for the current translation unit. If they are
different, complain and then ignore the PCH file. This effectively
checks for all compilation options that somehow would affect
preprocessor state (-D, -U, -include, the dreaded -imacros, etc.).
When we do accept the PCH file, throw away the contents of the
predefines buffer rather than parsing them, since all of the results
of that parsing are already stored in the PCH file. This eliminates
the ugliness with the redefinition of __builtin_va_list, among other
things.
llvm-svn: 68838
fixme's, e.g. for tokens with identifiers) but does not actually install
them. Some details with the predefines buffer needs to be sorted out first.
llvm-svn: 68828
file. When de-serializing LangOptions, we check that the
currently-provided language options are consistent with the options
used to compile the PCH file. If they are not, we emit a diagnostic
and ignore the PCH file.
llvm-svn: 68820
improvement, source locations read from the PCH file will properly
resolve to the source files that were used to build the PCH file
itself.
Once we have the preprocessor state stored in the PCH file, source
locations that refer to macro instantiations that occur in the PCH
file should have the appropriate instantiation information.
llvm-svn: 68758
de-serialization of abstract syntax trees.
PCH support serializes the contents of the abstract syntax tree (AST)
to a bitstream. When the PCH file is read, declarations are serialized
as-needed. For example, a declaration of a variable "x" will be
deserialized only when its VarDecl can be found by a client, e.g.,
based on name lookup for "x" or traversing the entire contents of the
owner of "x".
This commit provides the framework for serialization and (lazy)
deserialization, along with support for variable and typedef
declarations (along with several kinds of types). More
declarations/types, along with important auxiliary structures (source
manager, preprocessor, etc.), will follow.
llvm-svn: 68732
Douglas Gregor