Avoid a second key lookup when the back reference key is going to be
inserted in the StringMap. The string lookups in the msmangler are the
main responsible for the huge overhead when compared to the itanium
mangler. This patch makes a small but noticeable improvement.
Reviewed by: rnk
Differential Revision: http://reviews.llvm.org/D4130
Patch by Agustín Bergé!
llvm-svn: 211813
This is a follow-up to David's r211677. For the following code,
we would end up referring to 'foo' in the initializer for 'arr',
and then fail to link, because 'foo' is dllimport and needs to be
accessed through the __imp_?foo.
__declspec(dllimport) extern const char foo[];
const char* f() {
static const char* const arr[] = { foo };
return arr[0];
}
Differential Revision: http://reviews.llvm.org/D4299
llvm-svn: 211736
Types defined in function prototype are diagnosed earlier in C++ compilation.
They are put into declaration context where the prototype is introduced. Later on,
when FunctionDecl object is created, these types are moved into the function context.
This patch fixes PR19018 and PR18963.
Differential Revision: http://reviews.llvm.org/D4145
llvm-svn: 211718
The C++ language requires that the address of a function be the same
across all translation units. To make __declspec(dllimport) useful,
this means that a dllimported function must also obey this rule. MSVC
implements this by dynamically querying the import address table located
in the linked executable. This means that the address of such a
function in C++ is not constant (which violates other rules).
However, the C language has no notion of ODR nor does it permit dynamic
initialization whatsoever. This requires implementations to _not_
dynamically query the import address table and instead utilize a wrapper
function that will be synthesized by the linker which will eventually
query the import address table. The effect this has is, to say the
least, perplexing.
Consider the following C program:
__declspec(dllimport) void f(void);
typedef void (*fp)(void);
static const fp var = &f;
const fp fun() { return &f; }
int main() { return fun() == var; }
MSVC will statically initialize "var" with the address of the wrapper
function and "fun" returns the address of the actual imported function.
This means that "main" will return false!
Note that LLVM's optimizers are strong enough to figure out that "main"
should return true. However, this result is dependent on having
optimizations enabled!
N.B. This change also permits the usage of dllimport declarators inside
of template arguments; they are sufficiently constant for such a
purpose. Add tests to make sure we don't regress here.
llvm-svn: 211677
VarDecl provides a method getSourceRange(), which provides a more
robust way of getting the SourceRange since the TypeSourceInfo can
be null in certain cases.
Reviewed by: majnemer
Differential Revision: http://reviews.llvm.org/D4281
llvm-svn: 211667
The address of dllimport functions can be accessed one of two ways:
- Through the IAT which is symbolically referred to with a symbol
starting with __imp_.
- Via the wrapper-function which ends up calling through the __imp_
symbol.
The problem with using the wrapper-function is that it's address will
not compare as equal in all translation units. Specifically, it will
compare unequally with the translation unit which defines the function.
This fixes PR19955.
llvm-svn: 211570
The address of dllimport variables isn't something that can be
meaningfully used in a constexpr context and isn't suitable for
evaluation at load-time. They require loads from memory to properly
evaluate.
This fixes PR19955.
Differential Revision: http://reviews.llvm.org/D4250
llvm-svn: 211568
Something went wrong with r211426, it is an older version of this code
and should not have been committed. It was reverted with r211434.
Original commit message:
We didn't properly implement support for the sized integer suffixes.
Suffixes like i16 were essentially ignored instead of mapping them to
the appropriately sized integer type.
This fixes PR20008.
Differential Revision: http://reviews.llvm.org/D4132
llvm-svn: 211441
This reverts commit r211426.
This broke the arm bots. The crash can be reproduced on X86 by running.
./bin/clang -cc1 -fsyntax-only -verify -fms-extensions ~/llvm/clang/test/Lexer/ms-extensions.c -triple arm-linux
llvm-svn: 211434
We didn't properly implement support for the sized integer suffixes.
Suffixes like i16 were essentially ignored instead of mapping them to
the appropriately sized integer type.
This fixes PR20008.
Differential Revision: http://reviews.llvm.org/D4132
llvm-svn: 211426
This reverts commit r211096. Looks like it broke the msvc build:
SemaOpenMP.cpp(140) : error C4519: default template arguments are only allowed on a class template
llvm-svn: 211113
hint attributes. Includes tests for pragma printing and for attribute order
which is incorrectly reversed by ParsedAttributes.
Reviewed by Aaron Ballman
llvm-svn: 210925
Summary:
Do not store duplicate parents when memoization data is available.
This does not solve the duplication problem, but ameliorates it.
Reviewers: klimek
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D4124
llvm-svn: 210902
CRTP-like patterns involve a class which inherits from another class
using itself as a template parameter.
However, the base class itself may try to create a pointer-to-member
which involves the derived class. This is problematic because we
may not have finished parsing the most derived classes' base specifiers
yet.
It turns out that MSVC simply uses the unspecified inheritance model
instead of doing anything fancy.
This fixes PR19987.
llvm-svn: 210886
r210637 regressed CodeGenCXX/mangle-ms-templates-memptrs.cpp because it
did not believe that there is a distinction between class templates and
function templates.
Sadly, there is. Function templates should behave in a compatible
manner with MSVC.
llvm-svn: 210642
Summary:
Previously, we would mangle nullptr pointer-to-member-functions in class
templates with a mangling we invented because contemporary versions of
MSVC would crash when trying to compile such code.
However, VS "14" can successfully compile these sorts of template
instantiations. This commit updates our mangling to be compatible with
theirs.
Reviewers: rnk
Reviewed By: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4059
llvm-svn: 210637
The backing store of thread local variables is internal for OS X and all
accesses must go through the thread wrapper.
However, individual TUs may have inlined through the thread wrapper.
To fix this, give the thread wrapper functions WeakAnyLinkage. This
prevents them from getting inlined into call-sites.
This fixes PR19989.
llvm-svn: 210632
expression of array-of-unknown-bound type, don't try to complete the array
bound, and return the alignment of the element type rather than 1.
llvm-svn: 210608
will never be true in a well-defined context. The checking for null pointers
has been moved into the caller logic so it does not rely on undefined behavior.
llvm-svn: 210498
Use mangled template instantiation name as key for back references.
Templates have their own context for back references, so their mangling
is always the same regardless of context. This avoids mangling template
instantiations twice.
Patch by Agustín Bergé!
llvm-svn: 210416
MSVC delays parsing of default arguments until instantiation. If the
default argument is never used, it is never parsed. We don't model
this.
Instead, if lookup of a type name fails in a template argument context,
we form a DependentNameType, which will be looked up at instantiation
time.
This fixes errors about 'CControlWinTraits' in atlwin.h.
Reviewers: rsmith
Differential Revision: http://reviews.llvm.org/D3995
llvm-svn: 210382
Add driver and frontend support for the GCC -Wframe-larger-than=bytes warning.
This is the first GCC-compatible backend diagnostic built around LLVM's
reporting feature.
This commit adds infrastructure to perform reverse lookup from mangled names
emitted after LLVM IR generation. We use that to resolve precise locations and
originating AST functions, lambdas or block declarations to produce seamless
codegen-guided diagnostics.
An associated change, StringMap now maintains unique mangled name strings
instead of allocating copies. This is a net memory saving in C++ and a small
hit for C where we no longer reuse IdentifierInfo storage, pending further
optimisation.
llvm-svn: 210293
Craig Topper