record rather than relative to the start of the bitcode file. Saves a couple of
bytes per LOCAL_REDECLARATIONS record (also makes diffs of llvm-bcanalyzer
output more useful when tracking down nondeterminism...).
llvm-svn: 264359
Implement lambda capture of *this by copy.
For e.g.:
struct A {
int d = 10;
auto foo() { return [*this] (auto a) mutable { d+=a; return d; }; }
};
auto L = A{}.foo(); // A{}'s lifetime is gone.
// Below is still ok, because *this was captured by value.
assert(L(10) == 20);
assert(L(100) == 120);
If the capture was implicit, or [this] (i.e. *this was captured by reference), this code would be otherwise undefined.
Implementation Strategy:
- amend the parser to accept *this in the lambda introducer
- add a new king of capture LCK_StarThis
- teach Sema::CheckCXXThisCapture to handle by copy captures of the
enclosing object (i.e. *this)
- when CheckCXXThisCapture does capture by copy, the corresponding
initializer expression for the closure's data member
direct-initializes it thus making a copy of '*this'.
- in codegen, when assigning to CXXThisValue, if *this was captured by
copy, make sure it points to the corresponding field member, and
not, unlike when captured by reference, what the field member points
to.
- mark feature as implemented in svn
Much gratitude to Richard Smith for his carefully illuminating reviews!
llvm-svn: 263921
Add parsing, sema analysis and serialization/deserialization for 'declare reduction' construct.
User-defined reductions are defined as
#pragma omp declare reduction( reduction-identifier : typename-list : combiner ) [initializer ( initializer-expr )]
These custom reductions may be used in 'reduction' clauses of OpenMP constructs. The combiner specifies how partial results can be combined into a single value. The
combiner can use the special variable identifiers omp_in and omp_out that are of the type of the variables being reduced with this reduction-identifier. Each of them will
denote one of the values to be combined before executing the combiner. It is assumed that the special omp_out identifier will refer to the storage that holds the resulting
combined value after executing the combiner.
As the initializer-expr value of a user-defined reduction is not known a priori the initializer-clause can be used to specify one. Then the contents of the initializer-clause
will be used as the initializer for private copies of reduction list items where the omp_priv identifier will refer to the storage to be initialized. The special identifier
omp_orig can also appear in the initializer-clause and it will refer to the storage of the original variable to be reduced.
Differential Revision: http://reviews.llvm.org/D11182
llvm-svn: 262582
This is like r262493, but for pragma detect_mismatch instead of pragma comment.
The two pragmas have similar behavior, so use the same approach for both.
llvm-svn: 262506
`#pragma comment` was handled by Sema calling a function on ASTConsumer, and
CodeGen then implementing this function and writing things to its output.
Instead, introduce a PragmaCommentDecl AST node and hang one off the
TranslationUnitDecl for every `#pragma comment` line, and then use the regular
serialization machinery. (Since PragmaCommentDecl has codegen relevance, it's
eagerly deserialized.)
http://reviews.llvm.org/D17799
llvm-svn: 262493
If we import a module that has a complete array type and one that has an
incomplete array type, the declaration found by name lookup might be the one with
the incomplete type, possibly resulting in rejects-valid.
Now, the name lookup prefers decls with a complete array types. Also,
diagnose cases when the redecl chain has array bound, different from the merge
candidate.
Reviewed by Richard Smith.
llvm-svn: 262189
r261297 called hasUserProvidedDefaultConstructor() to check if defining a
const object is ok. This is incorrect for this example:
struct X { template<typename ...T> X(T...); int n; };
const X x; // formerly OK, now bogus error
Instead, track if a class has a defaulted default constructor, and disallow
a const object for classes that either have defaulted default constructors or
if they need an implicit constructor.
Bug report and fix approach by Richard Smith, thanks!
llvm-svn: 261770
C++11 requires const objects to have a user-provided constructor, even for
classes without any fields. DR 253 relaxes this to say "If the implicit default
constructor initializes all subobjects, no initializer should be required."
clang is currently the only compiler that implements this C++11 rule, and e.g.
libstdc++ relies on something like DR 253 to compile in newer versions. This
change makes it possible to build code that says `const vector<int> v;' again
when using libstdc++5.2 and _GLIBCXX_DEBUG
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60284).
Fixes PR23381.
http://reviews.llvm.org/D16552
llvm-svn: 261297
OMPCapturedExprDecl allows caopturing not only of fielddecls, but also
other expressions. It also allows to simplify codegen for several
clauses.
llvm-svn: 260492
OpenMP 4.5 introduces privatization of non-static data members of current class in non-static member functions.
To correctly handle such kind of privatization a new (pseudo)declaration VarDecl-based node is added. It allows to reuse an existing code for capturing variables in Lambdas/Block/Captured blocks of code for correct privatization and codegen.
llvm-svn: 260077
template, keep looking for default arguments if we see a template parameter
pack. There may be default arguments preceding a pack with no default argument.
Patch by Jannis Harder!
llvm-svn: 259836
By storing the instantiated expression back in the ParmVarDecl,
we remove the last need for separately storing the sub-expression
of a CXXDefaultArgExpr. This makes PCH/Modules merging quite
simple: CXXDefaultArgExpr records are serialized as references
to the ParmVarDecl, and we ignore redundant attempts to overwrite
the instantiated expression.
This has some extremely marginal impact on user-facing semantics.
However, the major effect is that it avoids IRGen errors about
conflicting definitions due to lambdas in the argument being
instantiated multiple times while sharing the same mangling.
It should also slightly improve memory usage and module file size.
rdar://23810407
llvm-svn: 256983
Also remove now-redundant explicit alignment specification on some of
the classes converted prior to TrailingObjects automatically ensuring
proper alignment.
llvm-svn: 256585
This new builtin template allows for incredibly fast instantiations of
templates like std::integer_sequence.
Performance numbers follow:
My work station has 64 GB of ram + 20 Xeon Cores at 2.8 GHz.
__make_integer_seq<std::integer_sequence, int, 90000> takes 0.25
seconds.
std::make_integer_sequence<int, 90000> takes unbound time, it is still
running. Clang is consuming gigabytes of memory.
Differential Revision: http://reviews.llvm.org/D13786
llvm-svn: 252036
r246546, with a workaround for an MSVC 2013 miscompile and an MSVC 2015
rejects-valid.
Original commit message:
[modules] Rework serialized DeclContext lookup table management. Instead of
walking the loaded ModuleFiles looking for lookup tables for the context, store
them all in one place, and merge them together if we find we have too many
(currently, more than 4). If we do merge, include the merged form in our
serialized lookup table, so that downstream readers never need to look at our
imports' tables.
This gives a huge performance improvement to builds with very large numbers of
modules (in some cases, more than a 2x speedup was observed).
llvm-svn: 246582
walking the loaded ModuleFiles looking for lookup tables for the context, store
them all in one place, and merge them together if we find we have too many
(currently, more than 4). If we do merge, include the merged form in our
serialized lookup table, so that downstream readers never need to look at our
imports' tables.
This gives a huge performance improvement to builds with very large numbers of
modules (in some cases, more than a 2x speedup was observed).
llvm-svn: 246497
A class without a name for linkage purposes gets a name along the lines
of <unnamed-type-foo> where foo is either the name of a declarator which
defined it (like a variable or field) or a
typedef-name (like a typedef or alias-declaration).
We handled the declarator case correctly but it would fall down during
template instantiation if the declarator didn't share the tag's type.
We failed to handle the typedef-name case at all.
Instead, keep track of the association between the two and keep it up to
date in the face of template instantiation.
llvm-svn: 246469
Instead of eagerly deserializing a list of DeclIDs when we load a module file
and doing a binary search to find the redeclarations of a decl, store a list of
redeclarations of each chain before the first declaration and load it directly.
llvm-svn: 245789
all modules and reduce the number of declarations we load when loading a
redeclaration chain.
The new approach is:
* when loading the first declaration of an entity within a module file, we
first load all declarations of the entity that were imported into that
module file, and then load all the other declarations of that entity from
that module file and build a suitable decl chain from them
* when loading any other declaration of an entity, we first load the first
declaration from the same module file
As before, we complete redecl chains through name lookup where necessary.
To make this work, I also had to change the way that template specializations
are stored -- it no longer suffices to track only canonical specializations; we
now emit all "first local" declarations when emitting a list of specializations
for a template.
On one testcase with several thousand imported module files, this reduces the
total runtime by 72%.
llvm-svn: 245779
arguments because the reloaded form might have become non-canonical across the
serialization/deserialization step (this particularly happens when the
canonical form of the type involves an expression).
llvm-svn: 244409
determine the primary context, rather than sometimes registering the lookup
table on the wrong context.
This exposed a couple of bugs:
* the odr violation check didn't deal properly with mergeable declarations
if the declaration retained by name lookup wasn't in the canonical
definition of the class
* the (broken) RewriteDecl mechanism would emit two name lookup tables for
the same DeclContext into the same module file (one as part of the
rewritten declaration and one as a visible update for the old declaration)
These are both fixed too.
llvm-svn: 244192
chain and fix the cases where it fires.
* Handle the __va_list_tag as a predefined decl. Previously we failed to merge
sometimes it because it's not visible to name lookup. (In passing, remove
redundant __va_list_tag typedefs that we were creating for some ABIs. These
didn't affect the mangling or representation of the type.)
* For Decls derived from Redeclarable that are not in fact redeclarable
(implicit params, function params, ObjC type parameters), remove them from
the list of expected redeclarable decls.
llvm-svn: 243259
before the first imported declaration.
We don't need to track all formerly-canonical declarations of an entity; it's sufficient to track those ones for which no other formerly-canonical declaration was imported into the same module. We call those ones "key declarations", and use them as our starting points for collecting redeclarations and performing namespace lookups.
llvm-svn: 241999
Introduce co- and contra-variance for Objective-C type parameters,
which allows us to express that (for example) an NSArray is covariant
in its type parameter. This means that NSArray<NSMutableString *> * is
a subtype of NSArray<NSString *> *, which is expected of the immutable
Foundation collections.
Type parameters can be annotated with __covariant or __contravariant
to make them co- or contra-variant, respectively. This feature can be
detected by __has_feature(objc_generics_variance). Implements
rdar://problem/20217490.
llvm-svn: 241549
When messaging a method that was defined in an Objective-C class (or
category or extension thereof) that has type parameters, substitute
the type arguments for those type parameters. Similarly, substitute
into property accesses, instance variables, and other references.
This includes general infrastructure for substituting the type
arguments associated with an ObjCObject(Pointer)Type into a type
referenced within a particular context, handling all of the
substitutions required to deal with (e.g.) inheritance involving
parameterized classes. In cases where no type arguments are available
(e.g., because we're messaging via some unspecialized type, id, etc.),
we substitute in the type bounds for the type parameters instead.
Example:
@interface NSSet<T : id<NSCopying>> : NSObject <NSCopying>
- (T)firstObject;
@end
void f(NSSet<NSString *> *stringSet, NSSet *anySet) {
[stringSet firstObject]; // produces NSString*
[anySet firstObject]; // produces id<NSCopying> (the bound)
}
When substituting for the type parameters given an unspecialized
context (i.e., no specific type arguments were given), substituting
the type bounds unconditionally produces type signatures that are too
strong compared to the pre-generics signatures. Instead, use the
following rule:
- In covariant positions, such as method return types, replace type
parameters with “id” or “Class” (the latter only when the type
parameter bound is “Class” or qualified class, e.g,
“Class<NSCopying>”)
- In other positions (e.g., parameter types), replace type
parameters with their type bounds.
- When a specialized Objective-C object or object pointer type
contains a type parameter in its type arguments (e.g.,
NSArray<T>*, but not NSArray<NSString *> *), replace the entire
object/object pointer type with its unspecialized version (e.g.,
NSArray *).
llvm-svn: 241543
Objective-C type arguments can be provided in angle brackets following
an Objective-C interface type. Syntactically, this is the same
position as one would provide protocol qualifiers (e.g.,
id<NSCopying>), so parse both together and let Sema sort out the
ambiguous cases. This applies both when parsing types and when parsing
the superclass of an Objective-C class, which can now be a specialized
type (e.g., NSMutableArray<T> inherits from NSArray<T>).
Check Objective-C type arguments against the type parameters of the
corresponding class. Verify the length of the type argument list and
that each type argument satisfies the corresponding bound.
Specializations of parameterized Objective-C classes are represented
in the type system as distinct types. Both specialized types (e.g.,
NSArray<NSString *> *) and unspecialized types (NSArray *) are
represented, separately.
llvm-svn: 241542
Produce type parameter declarations for Objective-C type parameters,
and attach lists of type parameters to Objective-C classes,
categories, forward declarations, and extensions as
appropriate. Perform semantic analysis of type bounds for type
parameters, both in isolation and across classes/categories/extensions
to ensure consistency.
Also handle (de-)serialization of Objective-C type parameter lists,
along with sundry other things one must do to add a new declaration to
Clang.
Note that Objective-C type parameters are typedef name declarations,
like typedefs and C++11 type aliases, in support of type erasure.
Part of rdar://problem/6294649.
llvm-svn: 241541
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
Introduce context-sensitive, non-underscored nullability specifiers
(nonnull, nullable, null_unspecified) for Objective-C method return
types, method parameter types, and properties.
Introduce Objective-C-specific semantics, including computation of the
nullability of the result of a message send, merging of nullability
information from the @interface of a class into its @implementation,
etc .
This is the Objective-C part of rdar://problem/18868820.
llvm-svn: 240154
VarDeclBitfields contained bits which are never present in parameters.
Split these out so that ParmVarDeclBitfields wouldn't grow past 32-bits
if another field was added.
llvm-svn: 237648
With this change, enabling -fmodules-local-submodule-visibility results in name
visibility rules being applied to submodules of the current module in addition
to imported modules (that is, names no longer "leak" between submodules of the
same top-level module). This also makes it much safer to textually include a
non-modular library into a module: each submodule that textually includes that
library will get its own "copy" of that library, and so the library becomes
visible no matter which including submodule you import.
llvm-svn: 237473
Modules builds fundamentally have a non-linear macro history. In the interest
of better source fidelity, represent the macro definition information
faithfully: we have a linear macro directive history within each module, and at
any point we have a unique "latest" local macro directive and a collection of
visible imported directives. This also removes the attendent complexity of
attempting to create a correct MacroDirective history (which we got wrong
in the general case).
No functionality change intended.
llvm-svn: 236176
if the merged definition is visible, and perform lookups into all merged copies
of the definition (not just for special members) so that we can complete the
redecl chains for members of the class.
llvm-svn: 233420
deserializing an inherited constructor.
This is the exact same logic we use when deserializing method overrides
for the same reason: the canonical decl may end up pinned to a different
decl when we are improting modules, we need to re-pin to the canonical
one during reading.
My test case for this will come in a subsequent commit. I was trying to
test a more tricky bug fix and the test case happened to tickle this bug
as well.
llvm-svn: 233325
non-visible definition, skip the new definition and make the old one visible
instead of trying to parse it again and failing horribly. C++'s ODR allows
us to assume that the two definitions are identical.
llvm-svn: 233250
More than 2x speedup on modules builds with large redecl chains.
Roughly 15-20% speedup on non-modules builds for very large TUs.
Between 2-3% cost in memory on large TUs.
llvm-svn: 233228
Previously we'd deserialize the list of mem-initializers for a constructor when
we deserialized the declaration of the constructor. That could trigger a
significant amount of unnecessary work (pulling in all base classes
recursively, for a start) and was causing problems for the modules buildbot due
to cyclic deserializations. We now deserialize these on demand.
This creates a certain amount of duplication with the handling of
CXXBaseSpecifiers; I'll look into reducing that next.
llvm-svn: 233052
for a DeclContext, and fix propagation of exception specifications along
redeclaration chains.
This reverts r232905, r232907, and r232907, which reverted r232793, r232853,
and r232853.
One additional change is present here to resolve issues with LLDB: distinguish
between whether lexical decls missing from the lookup table are local or are
provided by the external AST source, and still look in the external source if
that's where they came from.
llvm-svn: 232928
give an exception specification to a declaration that didn't have an exception
specification in any of our imported modules, emit an update record ourselves.
Without this, code importing the current module would not see an exception
specification that we could see and might have relied on.
llvm-svn: 232870
namespace to not merge properly.
We have an invariant here: after a declaration reads its canonical declaration,
it can assume the canonical declaration is fully merged. This invariant can be
violated if deserializing some declaration triggers the deserialization of a
later declaration, because that later declaration can in turn deserialize a
redeclaration of that first declaration before it is fully merged.
The anonymous namespace for a namespace gets stored with the first declaration
of that namespace, which may be before its parent namespace, so defer loading
it until after we've finished merging the surrounding namespace.
llvm-svn: 232455
definition, be sure to update the definition data on all declarations, not just
the canonical one, since the pattern might not be in the list of pending
definitions (if it used to be canonical itself).
One-line fix by me; reduced testcase by Daniel Jasper!
llvm-svn: 231950
specification, update all prior declarations if the new one has an explicit
exception specification and the prior ones don't.
Patch by Vassil Vassilev! Some minor tweaking and test case by me.
llvm-svn: 231738
move the operator delete updating into a separate update record so we can cope
with updating another module's destructor's operator delete.
llvm-svn: 231735
We used to save out and eagerly load a (potentially huge) table of merged
formerly-canonical declarations when we loaded each module. This was extremely
inefficient in the presence of large amounts of merging, and didn't actually
save any merging lookup work, because we still needed to perform name lookup to
check that our merged declaration lists were complete. This also resulted in a
loss of laziness -- even if we only needed an early declaration of an entity, we
would eagerly pull in all declarations that had been merged into it regardless.
We now store the relevant fragments of the table within the declarations
themselves. In detail:
* The first declaration of each entity within a module stores a list of first
declarations from imported modules that are merged into it.
* Loading that declaration pre-loads those other entities, so that they appear
earlier within the redeclaration chain.
* The name lookup tables list the most recent local lookup result, if there
is one, or all directly-imported lookup results if not.
llvm-svn: 231424
undeserialized specializations (because we merged an imported declaration of
the same template since we last added one), don't bother reading in the
specializations themselves just so we can write out their IDs again.
llvm-svn: 230805
entity, put the originally-canonical decl IDs in the right places in the redecl
chain rather than reordering them all to the start. If we don't ensure that the
redecl chain order is consistent with the topological module order, we can fail
to make a declaration visible if later declarations are in more IDNSs than
earlier ones (for instance, because the earlier decls are invisible friends).
llvm-svn: 228978
context as anonymous for merging purposes. They can't be found by their names,
so we merge them based on their position within the surrounding context.
llvm-svn: 228485
of that entity, ensure that the redeclaration chain is reordered properly on
reload. Otherwise, the result of name lookup for that entity may point to an
entity that is too old; if that's an injected friend name or the like, that
can result in the name not being found at all.
llvm-svn: 228371
object. In such a case, use the TU's DC for merging global decls rather than
giving up when we find there is no TU scope.
Ultimately, we should probably avoid all loading of decls when preprocessing,
but there are other reasonable use cases for loading an AST file with no Sema
object for which this is the right thing.
llvm-svn: 228234
encountered any definition for the class; this happens when the definition is
added by an update record that is not yet loaded. In such a case, eagerly pick
the original parent of the member as the canonical definition of the class
rather than muddling through with the canonical declaration (the latter can
lead to us failing to merge properly later if the canonical definition turns
out to be some other declaration).
llvm-svn: 226977
record, and that class declaration is not the canonical definition of the
class, be sure to add the class to the list of classes that are consulted when
we look up a special member in the canonical definition.
llvm-svn: 226778
on top of a local declaration of the same entity, we still need to remember
that we loaded the first one or we may fail to merge the second one properly.
llvm-svn: 226765
load the definition data from the declaration itself. In that case, merge
properly; don't assume the prior definition is the same as our own.
llvm-svn: 226761
For all threadprivate variables which have constructor/destructor emit call to void __kmpc_threadprivate_register(ident_t * <Current Location>, void *<Original Global Addr>, kmpc_ctor <Constructor>, kmpc_cctor NULL, kmpc_dtor <Destructor>);
In expressions all references to such variables are replaced by calls to void *__kmpc_threadprivate_cached(ident_t *<Current Location>, kmp_int32 <Current Thread Id>, void *<Original Global Addr>, size_t <Size of Data>, void ***<Pointer to autogenerated cache – array of private copies of threadprivate variable>);
Test test/OpenMP/threadprivate_codegen.cpp checks that codegen is correct. Also it checks that codegen is correct after serialization/deserialization and one of passes verifies debug info.
Differential Revision: http://reviews.llvm.org/D4002
llvm-svn: 221663
Implicit module builds are not well-suited to a lot of build systems. In
particular, they fare badly in distributed build systems, and they lead to
build artifacts that are not tracked as part of the usual dependency management
process. This change allows explicitly-built module files (which are already
supported through the -emit-module flag) to be explicitly loaded into a build,
allowing build systems to opt to manage module builds and dependencies
themselves.
This is only the first step in supporting such configurations, and it should
be considered experimental and subject to change or removal for now.
llvm-svn: 220359
initializers, and captured VLA types so that we can
answer questions like "is this a bit-field" without
looking at the enclosing DeclContext. NFC.
llvm-svn: 219522
on CXXRecordDecls when merging definitions, and make it pass by not trying to
save and restore this flag across AST serialization/deserialization. For
CXXRecordDecls, we have a separate mechanism to manage this.
llvm-svn: 216633
pattern of an alias template declaration. Use this to merge alias templates
properly when they're members of class template specializations.
llvm-svn: 216437
declarations. We can't expect to find them in the canonical definition
of the class, because that's not where they live.
This means we no longer reject real ODR violations with friend declarations,
but we weren't consistently doing so anyway.
llvm-svn: 216369
Predefined decls like 'Protocol' in objc are not loaded from AST files,
so we cannot rely on loading the canonical decl to complete the redecl
chain for redeclarations of these decls. The broken redecl chain was
non-circular, so looping over redecls() would hang.
llvm-svn: 215929
members from all redefinitions of a class that have them, in case the special
member is defined in one module but only declared in another.
llvm-svn: 215675
redefinitions of that namespace have already been loaded. When writing out the
names in a namespace, if we see a name that is locally declared and had
imported declarations merged on top of it, export the local declaration as the
lookup result, because it will be the most recent declaration of that entity in
the redeclaration chain of an importer of the module.
llvm-svn: 215518
also emit the updated 'operator delete' looked up for that destructor. Switch
from UpdateDecl to an actual update record when this happens due to implicitly
defining a special member function and unify this code path and the one for
instantiating a function definition.
llvm-svn: 215132
they're somehow missing a body. Looks like this was left behind when the loop
was generalized, and it's not been problematic before because without modules,
a used, implicit special member function declaration must be a definition.
This was resulting in us trying to emit a constructor declaration rather than
a definition, and producing a constructor missing its member initializers.
llvm-svn: 214473
of a function has a resolved exception specification, then all declarations of
the function do.
We should probably improve the AST representation to make this implicit (perhaps
only store the exception specification on the canonical declaration), but this
fixes things for now.
The testcase for this (which used to assert) also exposes the actual bug I was
trying to reduce here: we sometimes fail to emit the body of an imported
special member function definition. Fix for that to follow.
llvm-svn: 214458
FunctionProtoType::ExtProtoInfo. Most of the users of these fields don't care
about the other ExtProtoInfo bits and just want to talk about the exception
specification.
llvm-svn: 214450
redeclaration chains when pulling in a declaration. We need the redecl chain
unless we know some other declaration will trigger it to be pulled in; that
happens if our originally-canonical declaration had all the knowledge that
we have (and isn't us).
llvm-svn: 213043
into their container; we won't find them there. These things are already being
merged when they're added to their primary template's folding set, so this
merging is redundant (and causes us to reject-valid because we think we've
found an odr violation).
llvm-svn: 212788
member functions), ensure that the redecl chain never transitions from 'inline'
to 'not inline', since that violates an AST invariant.
llvm-svn: 209794
instantiated in another module, and the instantiation uses a partial
specialization, include the partial specialization and its template arguments
in the update record. We'll need them if someone imports the second module and
tries to instantiate a member of the template.
llvm-svn: 209472
declaration of that entity in from one of those modules, keep track of the fact
that we've not completed the redeclaration chain yet so that we can pull the
remaining declarations in from the other module if they're needed.
llvm-svn: 209161
ensure that querying the first declaration for its most recent declaration
checks for redeclarations from the imported module.
This works as follows:
* The 'most recent' pointer on a canonical declaration grows a pointer to the
external AST source and a generation number (space- and time-optimized for
the case where there is no external source).
* Each time the 'most recent' pointer is queried, if it has an external source,
we check whether it's up to date, and update it if not.
* The ancillary data stored on the canonical declaration is allocated lazily
to avoid filling it in for declarations that end up being non-canonical.
We'll still perform a redundant (ASTContext) allocation if someone asks for
the most recent declaration from a decl before setPreviousDecl is called,
but such cases are probably all bugs, and are now easy to find.
Some finessing is still in order here -- in particular, we use a very general
mechanism for handling the DefinitionData pointer on CXXRecordData, and a more
targeted approach would be more compact.
Also, the MayHaveOutOfDateDef mechanism should now be expunged, since it was
addressing only a corner of the full problem space here. That's not covered
by this patch.
Early performance benchmarks show that this makes no measurable difference to
Clang performance without modules enabled (and fixes a major correctness issue
with modules enabled). I'll revert if a full performance comparison shows any
problems.
llvm-svn: 209046
This fixes a bug where an update record causes us to load an entity that refers
to an entity we've not finished loading yet, resulting in badness.
llvm-svn: 207603
together. This is extremely hairy, because in general we need to have loaded
both the template and the pattern before we can determine whether either should
be merged, so we temporarily violate the rule that all merging happens before
reading a decl ends, but *only* in the case where a template's pattern is being
loaded while loading the template itself.
In order to accomodate this for class templates, delay loading the injected
class name type for the pattern of the template until after we've loaded the
template itself, if we happen to load the template first.
llvm-svn: 207063
Richard Smith