Commit Graph

10 Commits

Author SHA1 Message Date
David Majnemer 0c0b6d9ac6 MS ABI: Properly call global delete when invoking virtual destructors
Summary:
The Itanium ABI approach of using offset-to-top isn't possible with the
MS ABI, it doesn't have that kind of information lying around.

Instead, we do the following:
- Call the virtual deleting destructor with the "don't delete the object
  flag" set.  The virtual deleting destructor will return a pointer to
  'this' adjusted to the most derived class.
- Call the global delete using the adjusted 'this' pointer.

Reviewers: rnk

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D5996

llvm-svn: 220993
2014-10-31 20:09:12 +00:00
Reid Kleckner 0ba8ba4eca MS ABI: Emit more canonical vbptr stores and loads
This eliminates some i8* GEPs and makes the IR that clang emits a bit
more canonical. More work is needed for vftables, but that isn't a clear
win so I plan to send it for review.

llvm-svn: 220398
2014-10-22 17:26:00 +00:00
Hans Wennborg c94391d3bf MS ABI: Update the thunk linkage computation
As suggested by Reid:

 - class has GVA_Internal linkage -> internal
 - thunk has return adjustment -> weak_odr, to handle evil corner case [1]
 - all other normal methods -> linkonce_odr

 1. Evil corner case:

  struct Incomplete;
  struct A { int a; virtual A *bar(); };
  struct B { int b; virtual B *foo(Incomplete); };
  struct C : A, B { int c; virtual C *foo(Incomplete); };
  C c;

Here, the thunk for C::foo() will be emitted when C::foo() is defined, which
might be in a different translation unit, so it needs to be weak_odr.

Differential Revision: http://reviews.llvm.org/D3992

llvm-svn: 210368
2014-06-06 20:04:01 +00:00
Hans Wennborg c9bd88e681 Remove the -cxx-abi command-line flag.
This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250
2014-01-14 19:35:09 +00:00
Timur Iskhodzhanov 053142a90d Fix PR17738 - add support for vtordisp thunks when using -cxx-abi microsoft
llvm-svn: 194132
2013-11-06 06:24:31 +00:00
Timur Iskhodzhanov 0201432a5e Make thunk this/return adjustment ABI-specific. Also, fix the return adjustment when using -cxx-abi microsoft
Reviewed at http://llvm-reviews.chandlerc.com/D2026

llvm-svn: 193679
2013-10-30 11:55:43 +00:00
Reid Kleckner fe56be5819 Use castAs instead of cast in thunk generation
Calling convention attributes can add sugar to methods that we have to
look through.  This fixes an assertion failure in the provided test
case.

llvm-svn: 192496
2013-10-11 20:46:27 +00:00
Timur Iskhodzhanov ad9d3b8fd1 Reland 192220 "Abstract out parts of thunk emission code, add support for simple thunks when using -cxx-abi microsoft" with relaxed assertions
llvm-svn: 192285
2013-10-09 09:23:58 +00:00
Timur Iskhodzhanov c7113073dd Revert 192220 as it fails on an assertion
llvm-svn: 192225
2013-10-08 20:09:50 +00:00
Timur Iskhodzhanov 1ffb3916ce Abstract out parts of thunk emission code, add support for simple thunks when using -cxx-abi microsoft
Reviewed at http://llvm-reviews.chandlerc.com/D1787

llvm-svn: 192220
2013-10-08 19:15:38 +00:00