The ``disable_tail_calls`` attribute instructs the backend to not
perform tail call optimization inside the marked function.
For example,
int callee(int);
int foo(int a) __attribute__((disable_tail_calls)) {
return callee(a); // This call is not tail-call optimized.
}
Note that this attribute is different from 'not_tail_called', which
prevents tail-call optimization to the marked function.
rdar://problem/8973573
Differential Revision: http://reviews.llvm.org/D12547
llvm-svn: 252986
declarations in redeclaration lookup. A declaration is now visible to
lookup if:
* It is visible (not in a module, or in an imported module), or
* We're doing redeclaration lookup and it's externally-visible, or
* We're doing typo correction and looking for unimported decls.
We now support multiple modules having different internal-linkage or no-linkage
definitions of the same name for all entities, not just for functions,
variables, and some typedefs. As previously, if multiple such entities are
visible, any attempt to use them will result in an ambiguity error.
This patch fixes the linkage calculation for a number of entities where we
previously didn't need to get it right (using-declarations, namespace aliases,
and so on). It also classifies enumerators as always having no linkage, which
is a slight deviation from the C++ standard's definition, but not an observable
change outside modules (this change is being discussed on the -core reflector
currently).
This also removes the prior special case for tag lookup, which made some cases
of this work, but also led to bizarre, bogus "must use 'struct' to refer to type
'Foo' in this scope" diagnostics in C++.
llvm-svn: 252960
DR407, the C++ standard doesn't really say how this should work. Here's what we
do (which is consistent with DR407 as far as I can tell):
* When performing name lookup for an elaborated-type-specifier, a tag
declaration hides a typedef declaration that names the same type.
* When performing any other kind of lookup, a typedef declaration hides
a tag declaration that names the same type.
In any other case where lookup finds both a typedef and a tag (that is, when
they name different types), the lookup will be ambiguous. If lookup finds a
tag and a typedef that name the same type, and finds anything else, the lookup
will always be ambiguous (even if the other entity would hide the tag, it does
not also hide the typedef).
llvm-svn: 252959
This failed to solve the problem it was aimed at, and introduced just as many
issues as it resolved. Realistically, we need to deal with the possibility that
multiple modules might define different internal linkage symbols with the same
name, and this isn't a problem unless two such symbols are simultaneously
visible.
The case where two modules define equivalent internal linkage symbols is
handled by r252063: if lookup finds multiple sufficiently-similar entities from
different modules, we just pick one of them as an extension (but we keep them
separate).
llvm-svn: 252957
In r244063, I had caused these builtins to call the same-named library
functions, __atomic_*_fetch_SIZE. However, this was incorrect: while
those functions are in fact supported by GCC's libatomic, they're not
documented by the spec (and gcc doesn't ever call them).
Instead, you're /supposed/ to call the __atomic_fetch_* builtins and
then redo the operation inline to return the final value.
Differential Revision: http://reviews.llvm.org/D14385
llvm-svn: 252920
The C++ spec (3.6.1.3) says "The function `main` shall not be used within a program". This implies that it cannot recurse, so add the norecurse attribute to help the midend out a bit.
llvm-svn: 252902
Last time, this caused two Windows buildbots and a single ARM buildbot to fail.
I XFAIL'd the failing test on win32,win64 machines in order to see if the ARM
buildbot complains again.
llvm-svn: 252901
This function permits the mangling of a C++ 'structor. Depending on the ABI and
the declaration, the declaration may contain more than one associated symbol for
a given declaration. This allows the consumer to retrieve all of the associated
symbols for the declaration the cursor points to.
llvm-svn: 252853
This allows the return of a set of CXStrings from libclang. This is setup work
for an upcoming change to permit returning multiple mangled symbols.
llvm-svn: 252852
target features that the caller function doesn't provide. This matches
the existing backend failure to inline functions that don't have
matching target features - and diagnoses earlier in the case of
always_inline.
Fix up a few test cases that were, in fact, invalid if you tried
to generate code from the backend with the specified target features
and add a couple of tests to illustrate what's going on.
This should fix PR25246.
llvm-svn: 252834
This is about how we handle static member of a template. Before this commit,
we use internal linkage for the IR thread-local variable, which is inefficient.
With this commit, we will start to follow Itanium C++ ABI.
rdar://problem/23415206
Reviewed by John McCall.
llvm-svn: 252814
This allows COMPILER_RT_* variables to be passed from the top-level CMake into the external project when LLVM_BUILD_EXTERNAL_COMPILER_RT=On.
llvm-svn: 252809
Cwd::abs_path has a somewhat tricky semantics: if it's operand directory does not exist,
it'll return undefined (see https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=257568).
This may cause scan-build to silently ignore output directory (specified with -o) and
use /tmp instead of trying to create directory. This tiny patch fixes the problem.
A patch by Yury Gribov!
Differential Revision: http://reviews.llvm.org/D14535
llvm-svn: 252797
We used to emit the store prior to branch in the entry block. To make it more
efficient, this commit moves it to the init block. We still mark as initialized
before initializing anything else.
llvm-svn: 252777
Summary:
For clarity and ease of maintenance, I suggest porting this test
to use the same tooling as the rest of the tests.
Reviewers: joerg, rengolin, dougk, yaron.keren
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D14548
llvm-svn: 252720