Commit Graph

19 Commits

Author SHA1 Message Date
Richard Smith bab6df86ae Rework how UuidAttr, CXXUuidofExpr, and GUID template arguments and constants are represented.
Summary:
Previously, we treated CXXUuidofExpr as quite a special case: it was the
only kind of expression that could be a canonical template argument, it
could be a constant lvalue base object, and so on. In addition, we
represented the UUID value as a string, whose source form we did not
preserve faithfully, and that we partially parsed in multiple different
places.

With this patch, we create an MSGuidDecl object to represent the
implicit object of type 'struct _GUID' created by a UuidAttr. Each
UuidAttr holds a pointer to its 'struct _GUID' and its original
(as-written) UUID string. A non-value-dependent CXXUuidofExpr behaves
like a DeclRefExpr denoting that MSGuidDecl object. We cache an APValue
representation of the GUID on the MSGuidDecl and use it from constant
evaluation where needed.

This allows removing a lot of the special-case logic to handle these
expressions. Unfortunately, many parts of Clang assume there are only
a couple of interesting kinds of ValueDecl, so the total amount of
special-case logic is not really reduced very much.

This fixes a few bugs and issues:
 * PR38490: we now support reading from GUID objects returned from
   __uuidof during constant evaluation.
 * Our Itanium mangling for a non-instantiation-dependent template
   argument involving __uuidof no longer depends on which CXXUuidofExpr
   template argument we happened to see first.
 * We now predeclare ::_GUID, and permit use of __uuidof without
   any header inclusion, better matching MSVC's behavior. We do not
   predefine ::__s_GUID, though; that seems like a step too far.
 * Our IR representation for GUID constants now uses the correct IR type
   wherever possible. We will still fall back to using the
      {i32, i16, i16, [8 x i8]}
   layout if a definition of struct _GUID is not available. This is not
   ideal: in principle the two layouts could have different padding.

Reviewers: rnk, jdoerfert

Subscribers: arphaman, cfe-commits, aeubanks

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78171
2020-04-15 12:20:42 -07:00
Fangrui Song dbc96b518b Revert "[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition"
This reverts commit 789a46f2d7.

Accidentally committed.
2020-02-03 10:09:39 -08:00
Fangrui Song 789a46f2d7 [CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition
Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865
2020-02-03 09:52:48 -08:00
Daniel Neilson 6e938effaa Change memcpy/memove/memset to have dest and source alignment attributes (Step 1).
Summary:
  Upstream LLVM is changing the the prototypes of the @llvm.memcpy/memmove/memset
intrinsics. This change updates the Clang tests for this change.

  The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change removes the alignment argument in favour of placing the alignment
attribute on the source and destination pointers of the memory intrinsic call.

 For example, code which used to read:
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 At this time the source and destination alignments must be the same (Step 1).
Step 2 of the change, to be landed shortly, will relax that contraint and allow
the source and destination to have different alignments.

llvm-svn: 322964
2018-01-19 17:12:54 +00:00
Nico Weber 05e1dadac6 [ms] Add support for parsing uuid as a Microsoft attribute.
Some Windows SDK classes, for example
Windows::Storage::Streams::IBufferByteAccess, use the ATL way of spelling
attributes:

  [uuid("....")] class IBufferByteAccess {};

To be able to use __uuidof() to grab the uuid off these types, clang needs to
support uuid as a Microsoft attribute. There was already code to skip Microsoft
attributes, extend that to look for uuid and parse it.  Use the new "Microsoft"
attribute type added in r280575 (and r280574, r280576) for this.

Final part of https://reviews.llvm.org/D23895

llvm-svn: 280578
2016-09-03 03:25:22 +00:00
David Majnemer 6568760090 Use the correct alignment for uuid descriptors
The _GUID_ descriptors emitted by MSVC have alignment 8 for 64-bit
builds: we should do the same if the linker picks the "wrong" COMDAT.

llvm-svn: 264530
2016-03-27 04:46:14 +00:00
Pete Cooper 3b39e88ae0 Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253512.

This likely broke the bots in:
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253542
2015-11-19 05:55:59 +00:00
Pete Cooper 7bfd5cb7be Change memcpy/memset/memmove to have dest and source alignments.
This is a follow on from a similar LLVM commit: r253511.

Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

The only code change to clang is hidden in CGBuilder.h which now passes
both dest and source alignment to IRBuilder, instead of taking the minimum of
dest and source alignments.

Reviewed by Hal Finkel.

llvm-svn: 253512
2015-11-18 22:18:45 +00:00
David Majnemer 740d59ec49 CodeGen: Compiler generated __declspec(uuid) objects should be COMDAT'd
llvm-svn: 226628
2015-01-21 01:04:28 +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
Hans Wennborg 442e4f7f5f Prepare for using MS ABI by default for Win32: update CodeGenCXX tests
llvm-svn: 197281
2013-12-13 22:43:52 +00:00
Reid Kleckner b9921df29c Emit uuid globals as linkonce_odr
Patch by Nico Rieck!

llvm-svn: 189860
2013-09-03 21:49:32 +00:00
David Majnemer bbecd09658 CodeGen: __uuidof should work even with an incomplete _GUID type
Summary:
We would crash in CodeGen::CodeGenModule::EmitUuidofInitializer
because our attempt to enter CodeGen::CodeGenModule::EmitConstantValue
will be foiled: the type of the constant value is incomplete.

Instead, create an unnamed type with the proper layout on all platforms.
Punt the problem of wrongly defined struct _GUID types to the user.
(It's impossible because the TU may never get to see the type and thus
we can't verify that it is suitable.)

This fixes PR16856.

Reviewers: rsmith, rnk, thakis

Reviewed By: rnk

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1375

llvm-svn: 188481
2013-08-15 19:59:14 +00:00
David Majnemer 89085340be Sema: Assertion failure during CodeGen in CodeGenModule::EmitUuidofInitializer
Make sure we can properly generate code when the UUID has curly braces
on it, strip the curly braces at the sema layer.

This fixes PR16813.

llvm-svn: 188061
2013-08-09 08:56:20 +00:00
David Majnemer cf963cece8 [-cxx-abi microsoft] Mangle UUIDs correctly, stick them in the proper section
Revert r188055 which reverted r188053. An unrelated change previously snuck in.

llvm-svn: 188060
2013-08-09 08:35:59 +00:00
David Majnemer a2724ae4b3 Revert "[-cxx-abi microsoft] Mangle UUIDs correctly, stick them in the proper section"
This commit reverts r188053.

It is breaking the build bots.

llvm-svn: 188055
2013-08-09 05:56:24 +00:00
David Majnemer 94a76b64e0 [-cxx-abi microsoft] Mangle UUIDs correctly, stick them in the proper section
We mangled them like:
L___uuid_12345678-1234-1234-1234-123456789abc

We should've mangled them like:
__GUID_12345678_1234_1234_1234_123456789abc

Furthermore, they are external symbols.

llvm-svn: 188053
2013-08-09 05:09:04 +00:00
NAKAMURA Takumi 5bbb4fa3a6 clang/test/CodeGenCXX/microsoft-uuidof.cpp: Fix for -Asserts.
llvm-svn: 165712
2012-10-11 11:20:31 +00:00
Nico Weber cf4ff586e8 Add codegen support for __uuidof().
llvm-svn: 165710
2012-10-11 10:13:44 +00:00