This undoes half of r208786.
It had problems with lazily declared special members in cases like this:
struct A {
A();
A &operator=(A &&o);
void *p;
};
void foo(A);
void bar() {
foo({});
}
In this case, the copy and move constructors are implicitly deleted.
However, Clang doesn't eagerly declare the copy ctor in the AST, so we
pass the struct in registers. Furthermore, GCC passes this in registers
even though this class should be uncopyable.
Revert this for now until the dust settles.
llvm-svn: 208836
This affects both the Itanium and Microsoft C++ ABIs.
This is in anticipation of a change to the Itanium C++ ABI, and should
match GCC's current behavior. The new text will likely be:
"""
Pass an object of class type by value if every copy constructor and
move constructor is deleted or trivial and at least one of them is not
deleted, and the destructor is trivial.
"""
http://sourcerytools.com/pipermail/cxx-abi-dev/2014-May/002728.html
On x86 Windows, we can mostly use the same logic, where we use inalloca
instead of passing by address. However, on Win64, there are register
parameters, and we have to do what MSVC does. MSVC ignores the presence
of non-trivial move constructors and only considers the presence of
non-trivial or deleted copy constructors. If a non-trivial or deleted
copy ctor is present, it passes the argument indirectly.
This change fixes bugs and makes us more ABI compatible with both GCC
and MSVC.
Fixes PR19668.
Reviewers: rsmith
Differential Revision: http://reviews.llvm.org/D3660
llvm-svn: 208786
In the Microsoft C++ ABI, instance methods always return records
indirectly via the second hidden parameter. This was implemented in
X86_32ABIInfo, but not WinX86_64ABIInfo.
Rather than exposing a handful of boolean methods in the CGCXXABI
interface, we can expose a single method that applies C++ ABI return
value classification rules.
llvm-svn: 208733
Also tidy up, simplify, and extend the test coverage to demonstrate the
limitations. This test should now fail if the bugs are fixed (&
hopefully whoever ends up in this situation sees the FIXMEs and realizes
that the test needs to be updated to positively test their change that
has fixed some or all of these issues).
I do wonder whether I could demonstrate breakage without a macro here,
but any way I slice it I can't think of a way to get two calls to the
same function on the same line/column in non-macro C++ - implicit
conversions happen at the same location as an explicit function, but
you'd never get an implicit conversion on the result of an explicit call
to the same implicit conversion operator (since the value is already
converted to the desired result)...
llvm-svn: 208468
Summary:
MSVC always passes 'sret' after 'this', unlike GCC. This required
changing a number of places in Clang that assumed the sret parameter was
always first in LLVM IR.
This fixes win64 MSVC ABI compatibility for methods returning structs.
Reviewers: rsmith, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D3618
llvm-svn: 208458
It was set by default on Darwin in r198655. The same usability issues
with DTrace and LLDB apply to FreeBSD, so set it by default there too.
rdar://problem/15758808
http://llvm.org/pr19676
Differential Revision: http://reviews.llvm.org/D3448
llvm-svn: 208310
r154191 switched to atexit() instead of global destructors, so the intent
was probably to check for _GLOBAL__D_a _not_ being in the output. There already
is a line for _ZN3barD1Ev further up, so just remove the CH_ECK line referring
to that.
The only circumstance in which clang emits _GLOBAL__D_a destructor symbols is
for -fapple-kext, and that is tested by test/CodeGenCXX/cxx-apple-kext.cpp.
llvm-svn: 208222
Summary:
Update our mangling to match the discussion on cxx-abi-dev.
This involves using a seq-id instead of an optional number.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D3631
llvm-svn: 208140
This makes it easier to see where a global ctor comes from, and it also makes
ASan's init order analyzer output easier to understand. gcc does this too,
but only in -fPIC mode for some reason. Don't do this for constructors with
explicit init priority.
Also prepend "sub_" before the 'I', that way regular constructors stay
lexicographically after symbols with init priority (because
ord('s') > ord('I')). gold seems to ignore the name of constructor symbols,
and ld only looks at the symbol if it includes an init priority, which this
patch doesn't change.
Before: __GLOBAL_I_a
Now: __GLOBAL_sub_I_myfile.cc
llvm-svn: 208128
Reverting r208106 to reapply r208065 with a fix for the regression. The
issue was that the enum tried to be built even if the declaration hadn't
been constructed for debug info - presenting problems for enum templates
and typedefs of enums with names for linkage purposes.
Original commit message:
This regressed a little further 208055 though it was already a little
broken.
While the requiresCompleteType optimization should be implemented here.
Future (possibly near future) work.
llvm-svn: 208114
This regressed a little further 208055 though it was already a little
broken.
While the requiresCompleteType optimization should be implemented here.
Future (possibly near future) work.
llvm-svn: 208065
Currently, users get error messages about RTTI descriptor mangling with
no useful source location. This addresses that.
Another approach would be to disable C++ exceptions by default in the
driver when using the Microsoft C++ ABI. However, this makes it
impossible to parse system headers that use exception handling
constructs. By delaying the error to IRgen, we can figure out if we
actually need to emit code for this construct. Additionally, users who
are only interested in building refactoring tools on Windows still get a
correct AST without having to add flags. Finally, this is consistent
with what we do for SEH.
llvm-svn: 207999
We would sometimes incorrectly give a thread-wrapper external linkage
instead of internal linkage if we had only CodeGen'd it's declaration,
not it's definition.
This fixes PR19655.
llvm-svn: 207988
Passing objects directly (in registers or memory) creates a second copy
of the object in the callee. The callee always destroys its copy, but
we also have to destroy any temporary created in the caller. In other
words, copy elision of these kinds of objects is impossible.
Objects larger than 8 bytes with non-trivial dtors and trivial copy
ctors are still passed indirectly, and we can still elide copies of
them.
Fixes PR19640.
llvm-svn: 207889
dependent-type-member-pointer.cpp is failing on a win64 bot because
-fms-extensions is not enabled. Use ConvertType rather than relying on
the inheritance attributes. It's less code, but probably slower.
llvm-svn: 207819
The Win64 ABI docs on MSDN say that arguments bigger than 8 bytes are
passed by reference. Prior to this change, we were only applying this
logic to RecordType arguments. This affects both the Itanium and
Microsoft C++ ABIs.
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D3587
llvm-svn: 207817
This code is trying to test if the pointer is *not* null. Therefore we
should use 'or' instead of 'and' to combine the results of 'icmp ne'.
This logic is consistent with the general member pointer comparison code
in EmitMemberPointerComparison.
llvm-svn: 207815
To simplify source location offsets, this test uses line directives to
force particular lines of interest to have known line numbers so that
adjustments before/after those points don't require updates to the CHECK
lines.
llvm-svn: 207779
Summary:
Previously, we would generate a single name for all reference
temporaries and allow LLVM to rename them for us. Instead, number the
reference temporaries as we build them in Sema.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D3554
llvm-svn: 207776
We accept 'void *p; p->~void();' for MSVC compatibility since r148682.
However, we were returning ExprError, rather than producing an AST,
despite only diagnosing it with a warning. CodeGen noticed that the
template function specialization had an invalid AST, and therefore
didn't generate code for it. This change makes us produce an AST with a
void pseudo-dtor call.
Part of PR18256.
llvm-svn: 207771
We were destroying them in the callee, and then again in the caller. We
should use an EH-only cleanup and disable it at the point of the call
for win64, even though we don't use inalloca.
llvm-svn: 207733
It is possible that a variable template specialization might not have a
VisibilityAttr attached to it while the template that it specializes
does, in fact, have one.
We should consider the template in such cases.
This fixes PR19597.
llvm-svn: 207498
Summary:
A reference temporary should inherit the linkage of the variable it
initializes. Otherwise, we may hit cases where a reference temporary
wouldn't have the same value in all translation units.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D3515
llvm-svn: 207451
Prior to this patch, CGRecordLower assumed that virtual bases could not
be placed before the nvsize of an object. This isn't true in Itanium
mode, virtual bases are placed at dsize rather than vnsize and in the
case of zero sized non-virtual bases nvsize can be larger than dsize.
This patch fixes CGRecordLowering to avoid an assert and to clip
bitfields properly in this case. A test case is included.
llvm-svn: 207280
after we've already instantiated a definition for the function, pass it to the
ASTConsumer again so that it knows the specialization kind has changed and can
update the function's linkage.
This only matters if we instantiate the definition of the function before we
reach the end of the TU; this can happen in at least three different ways:
C++11 constexpr functions, C++14 deduced return types, and functions
instantiated within modules.
llvm-svn: 207152
Summary:
Correct size_t to be unsigned int and ptrdiff_t to be signed long. The types were the correct size before this change but
the exact type matters for name mangling and exception handling in C++.
Reviewers: atanasyan
Reviewed By: atanasyan
Differential Revision: http://reviews.llvm.org/D3470
llvm-svn: 207093
We were using the same guard variable and failing to initialize the
second global.
Clang is still not MS ABI compatible in this area. Fixing that is
PR16959, which will require LLVM changes to @llvm.global_ctors.
llvm-svn: 207008
We previously treated ARM separately from the generic Itanium ABI for
initializing guard variables. This code duplication led to things like
the ARM path missing the memory barrier for threadsafe handling, and a
highly misleading comment about how we were (mis)using the generic ABI
for ARM64 when really it went through the ARM codepath.
This unifies the two code paths. Functionally, this changes the ARM
and ARM64 codepath to use one byte loads instead of 4 and 8,
respectively, and adds the missing atomic acquire to these loads.
Other architectures are unchanged.
llvm-svn: 206937
specializations collect all arguments and not just the ones from the
class template partial specialization from which this class template
specialization was instantiated. The debug info does not represent the
partial specialization otherwise and so specialized parameters would
go missing.
rdar://problem/16636569.
llvm-svn: 206430
Reid Kleckner