deterministically.
This fixes a latent issue where even Clang's Sema (and diagnostics) were
non-deterministic in the face of this pragma. The fix is super simple --
just use a MapVector so we track the order in which these are parsed (or
imported). Especially considering how rare they are, this seems like the
perfect tradeoff. I've also simplified the client code with judicious
use of auto and range based for loops.
I've added some pretty hilarious code to my stress test which now
survives the binary diff without issue.
llvm-svn: 233261
updated decl contexts get emitted.
Since this code was added, we have newer vastly simpler code for
handling this. The code I'm removing was very expensive and also
generated unstable order of declarations which made module outputs
non-deterministic.
All of the tests continue to pass for me and I'm able to check the
difference between the .pcm files after merging modules together.
llvm-svn: 233251
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
decl context lookup tables.
The first attepmt at this caused problems. We had significantly more
sources of non-determinism that I realized at first, and my change
essentially turned them from non-deterministic output into
use-after-free. Except that they weren't necessarily caught by tools
because the data wasn't really freed.
The new approach is much simpler. The first big simplification is to
inline the "visit" code and handle this directly. That works much
better, and I'll try to go and clean up the other caller of the visit
logic similarly.
The second key to the entire approach is that we need to *only* collect
names into a stable order at first. We then need to issue all of the
actual 'lookup()' calls in the stable order of the names so that we load
external results in a stable order. Once we have loaded all the results,
the table of results will stop being invalidated and we can walk all of
the names again and use the cheap 'noload_lookup()' method to quickly
get the results and serialize them.
To handle constructors and conversion functions (whose names can't be
stably ordered) in this approach, what we do is record only the visible
constructor and conversion function names at first. Then, if we have
any, we walk the decls of the class and add those names in the order
they occur in the AST. The rest falls out naturally.
This actually ends up simpler than the previous approach and seems much
more robust.
It uncovered a latent issue where we were building on-disk hash tables
for lookup results when the context was a linkage spec! This happened to
dodge all of the assert by some miracle. Instead, add a proper predicate
to the DeclContext class and use that which tests both for function
contexts and linkage specs.
It also uncovered PR23030 where we are forming somewhat bizarre negative
lookup results. I've just worked around this with a FIXME in place
because fixing this particular Clang bug seems quite hard.
I've flipped the first part of the test case I added for stability back
on in this commit. I'm taking it gradually to try and make sure the
build bots are happy this time.
llvm-svn: 233249
lookup tables, we need to establish a stable ordering for constructing
the hash table. This is trickier than it might seem.
Most of these cases are easily handled by sorting the lookup results
associated with a specific name that has an identifier. However for
constructors and conversion functions, the story is more complicated.
Here we need to merge all of the constructors or conversion functions
together and this merge needs to be stable. We don't have any stable
ordering for either constructors or conversion functions as both would
require a stable ordering across types.
Instead, when we have constructors or conversion functions in the
results, we reconstruct a stable order by walking the decl context in
lexical order and merging them in the order their particular declaration
names are encountered. This doesn't generalize as there might be found
declaration names which don't actually occur within the lexical context,
but for constructors and conversion functions it is safe. It does
require loading the entire decl context if necessary to establish the
ordering but there doesn't seem to be a meaningful way around that.
Many thanks to Richard for talking through all of the design choices
here. While I wrote the code, he guided all the actual decisions about
how to establish the order of things.
No test case yet because the test case I have doesn't pass yet -- there
are still more sources of non-determinism. However, this is complex
enough that I wanted it to go into its own commit in case it causes some
unforseen issue or needs to be reverted.
llvm-svn: 233156
There are two aspects of non-determinism fixed here, which was the
minimum required to cause at least an empty module to be deterministic.
First, the random number signature is only inserted into the module when
we are building modules implicitly. The use case for these random
signatures is to work around the very fact that modules are not
deterministic in their output when working with the implicitly built and
populated module cache. Eventually this should go away entirely when
we're confident that Clang is producing deterministic output.
Second, the on-disk hash table is populated based on the order of
iteration over a DenseMap. Instead, use a MapVector so that we can walk
it in insertion order.
I've added a test that an empty module, when built twice, produces the
same binary PCM file.
llvm-svn: 233115
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
Now that SmallString is a first-class citizen, most SmallString::str()
calls are not required. This patch removes a whole bunch of them, yet
there are lots more.
There are two use cases where str() is really needed:
1) To use one of StringRef member functions which is not available in
SmallString.
2) To convert to std::string, as StringRef implicitly converts while
SmallString do not. We may wish to change this, but it may introduce
ambiguity.
llvm-svn: 232622
consumers of that module.
Previously, such a file would only be available if the module happened to
actually import something from that module.
llvm-svn: 232583
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
of extern "C" declarations. This is simpler and vastly more efficient for
modules builds (we no longer need to load *all* extern "C" declarations to
determine if we have a redeclaration).
No functionality change intended.
llvm-svn: 231538
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
dynamic classes in the translation unit and check whether each one's key
function is defined when we got to the end of the TU (and when we got to the
end of each module). This is really terrible for modules performance, since it
causes unnecessary deserialization of every dynamic class in every compilation.
We now use a much simpler (and, in a modules build, vastly more efficient)
system: when we see an out-of-line definition of a virtual function, we check
whether that function was in fact its class's key function. (If so, we need to
emit the vtable.)
llvm-svn: 230830
invalidate lookup_iterators and lookup_results for some name within a
DeclContext if the lookup results for a *different* name change.
llvm-svn: 230121
the one in the current compiler invocation. If they differ reject the PCH.
This protects against the badness occurring from getting modules loaded from different module caches (see crashes).
rdar://19889860
llvm-svn: 229909
When mangling the module map path into a .pcm file name, also mangle the
IsSystem bit, which can also depend on the header search paths. For
example, the user may change from -I to -isystem. This can affect
diagnostics in the importing TU.
llvm-svn: 228966
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
This fixes PR21587, what r221933 fixed for regular programs is now also
fixed for decls coming from PCH files.
Use another bit from the count/bits uint16_t for storing the "more than one
decl" bit. This reduces the number of bits for the count from 14 to 13.
The selector with the most overloads in Cocoa.h has ~55 overloads, so 13 bits
should still be plenty. Since this changes the meaning of a serialized bit
pattern, also increase clang::serialization::VERSION_MAJOR.
Storing the "more than one decl" state of only the first overload isn't quite
correct, but Sema::AreMultipleMethodsInGlobalPool() currently only looks at
the state of the first overload so it's good enough for now.
llvm-svn: 224892
Remove ObjCMethodList::Count, instead store a "has more than one decl" bit in
the low bit of the ObjCMethodDecl pointer, using a PointerIntPair.
Most of this patch is replacing ".Method" with ".getMethod()".
No intended behavior change.
llvm-svn: 224876
components. These sometimes get synthetically added, and we don't want -Ifoo
and -I./foo to be treated fundamentally differently here.
llvm-svn: 224055
the root of the module and use paths relative to that directory wherever
possible. This is a step towards allowing explicit modules to be relocated
without being rebuilt, which is important for some kinds of distributed builds,
for good paths in diagnostics, and for appropriate .d output.
This is a recommit of r223443, reverted in r223465; when joining together
imported file paths, we now use the system's separator rather than always
using '/'. This avoids path mismatches between the original module build and
the module user on Windows (at least, in some cases). A more comprehensive
fix will follow.
llvm-svn: 223539
the root of the module and use paths relative to that directory wherever
possible. This is a step towards allowing explicit modules to be relocated
without being rebuilt, which is important for some kinds of distributed builds,
for good paths in diagnostics, and for appropriate .d output.
llvm-svn: 223443
rather than trying to extract this information from the FileEntry after the
fact.
This has a number of beneficial effects. For instance, diagnostic messages for
failed module builds give a path relative to the "module root" rather than an
absolute file path, and the contents of the module includes file is no longer
dependent on what files the including TU happened to inspect prior to
triggering the module build.
llvm-svn: 223095
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
Use the bitmask to store the set of enabled sanitizers instead of a
bitfield. On the negative side, it makes syntax for querying the
set of enabled sanitizers a bit more clunky. On the positive side, we
will be able to use SanitizerKind to eventually implement the
new semantics for -fsanitize-recover= flag, that would allow us
to make some sanitizers recoverable, and some non-recoverable.
No functionality change.
llvm-svn: 221558
Since the order of the IDs in the AST file (e.g. DeclIDs, SelectorIDs)
is not stable, it is not safe to load an AST file that depends on
another AST file that has been rebuilt since the importer was built,
even if "nothing changed". We previously used size and modtime to check
this, but I've seen cases where a module rebuilt quickly enough to foil
this check and caused very hard to debug build errors.
To save cycles when we're loading the AST, we just generate a random
nonce value and check that it hasn't changed when we load an imported
module, rather than actually hash the whole file.
This is slightly complicated by the fact that we need to verify the
signature inside addModule, since we might otherwise consider that a
mdoule is "OutOfDate" when really it is the importer that is out of
date. I didn't see any regressions in module load time after this
change.
llvm-svn: 220493
This allows a module to specify that it logically contains a file, but that
said file is non-modular and intended for textual inclusion. This allows
layering checks to work properly in the presence of such files.
llvm-svn: 220448
This is a better fix for 'duplicate key' problems in module continuous
range maps (vs what I added in r215810) by not adding any mappings at
all when there are no local entities. Now it also covers selectors,
which were not always being bumped because the record SELECTOR_OFFSET is
not always emitted. I'll back out most of r215810 in a future commit,
since it should no longer be needed.
llvm-svn: 220207
Plumb through the full QualType of the TemplateArgument::Declaration, as
it's insufficient to only know whether the type is a reference or
pointer (that was necessary for mangling, but insufficient for debug
info). This shouldn't increase the size of TemplateArgument as
TemplateArgument::Integer is still longer by another 32 bits.
Several bits of code were testing that the reference-ness of the
parameters matched, but this seemed to be insufficient (various other
features of the type could've mismatched and wouldn't've been caught)
and unnecessary, at least insofar as removing those tests didn't cause
anything to fail.
(Richard - perchaps you can hypothesize why any of these checks might
need to test reference-ness of the parameters (& explain why
reference-ness is part of the mangling - I would've figured that for the
reference-ness to be different, a prior template argument would have to
be different). I'd be happy to add them in/beef them up and add test
cases if there's a reason for them)
llvm-svn: 219900
