Commit Graph

16 Commits

Author SHA1 Message Date
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
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
Benjamin Kramer f8b86964ca Reapply r231508 "CodeGen: Emit constant temporaries into read-only globals."
I disabled putting the new global into the same COMDAT as the function for now.
There's a fundamental problem when we inline references to the global but still
have the global in a COMDAT linked to the inlined function. Since this is only
an optimization there may be other versions of the COMDAT around that are
missing the new global and hell breaks loose at link time.

I hope the chromium build doesn't break this time :)

llvm-svn: 231564
2015-03-07 13:37:13 +00:00
Hans Wennborg cd8f011157 Revert r231508 "CodeGen: Emit constant temporaries into read-only globals."
This broke the Chromium build. Links were failing with messages like:

obj/dbus/libdbus_test_support.a(obj/dbus/dbus_test_support.mock_object_proxy.o):../../dbus/mock_object_proxy.cc:function dbus::MockObjectProxy::Detach(): warning: relocation refers to discarded section
/usr/local/google/work/chromium/src/third_party/binutils/Linux_x64/Release/bin/ld.gold: error: treating warnings as errors

llvm-svn: 231541
2015-03-07 00:46:19 +00:00
Benjamin Kramer 3d8aa5c77d CodeGen: Emit constant temporaries into read-only globals.
Instead of creating a copy on the stack just stash them in a private
constant global. This saves both the copying overhead and the stack
space, and gives the optimizer more room to constant fold.

This tries to make array temporaries more similar to regular arrays,
they can't use the same logic because a temporary has no VarDecl to be
bound to so we roll our own version here.

The original use case for this optimization was code like
  for (int i : {1, 2, 3, 4, 5, 6, 7, 8, 10})
    foo(i);
where without this patch (assuming that the loop is not unrolled) we
would alloca an array on the stack, copy the 10 values over and
iterate on that. With this patch we put the array in .text use it
directly. Apart from that case this helps on virtually any passing of
a constant std::initializer_list as a function argument.

Differential Revision: http://reviews.llvm.org/D8034

llvm-svn: 231508
2015-03-06 20:00:03 +00:00
Stephen Lin 4362261b00 CHECK-LABEL-ify some code gen tests to improve diagnostic experience when tests fail.
llvm-svn: 188447
2013-08-15 06:47:53 +00:00
Richard Smith c084bd2888 PR15132: Replace "address expression must be an lvalue or a function
designator" diagnostic with more correct and more human-friendly "cannot take
address of rvalue of type 'T'".

For the case of & &T::f, provide a custom diagnostic, rather than unhelpfully
saying "cannot take address of rvalue of type '<overloaded function type>'".

For the case of &array_temporary, treat it just like a class temporary
(including allowing it as an extension); the existing diagnostic wording
for the class temporary case works fine.

llvm-svn: 174262
2013-02-02 02:14:45 +00:00
Richard Smith d712d0dbdd Don't forget to run destructors when we create an array temporary of class type.
llvm-svn: 174257
2013-02-02 01:13:06 +00:00
Richard Smith d82a2ce3a0 Reinstate r170806, reverted in r170835, with a fix use i1 instead of i8 for a value-initialized bool!
llvm-svn: 170837
2012-12-21 03:17:28 +00:00
NAKAMURA Takumi 3df909d030 Revert r170806, "Fix some bugs where we would sometimes use 0, not -1, when emitting a null constant of type pointer-to-data-member."
It broke stage2.

llvm-svn: 170835
2012-12-21 02:50:38 +00:00
Richard Smith 789ce142df Fix some bugs where we would sometimes use 0, not -1, when emitting a null constant of type pointer-to-data-member.
llvm-svn: 170806
2012-12-20 23:49:09 +00:00
Ulrich Weigand 35668cc401 A number of test cases assume that an "int" parameter or return value
will be represented in the IR as a plain "i32" type.  This causes the
tests to spuriously fail on platforms where int is not a 32-bit type,
or where the ABI requires attributes like "signext" or "zeroext" to
be used.

This patch adds -triple or -target parameters to force those tests
to use the i386-unknown-unknown target.

llvm-svn: 166551
2012-10-24 12:22:56 +00:00
Eli Friedman 576cbd03b4 Make sure list-initialization of arrays works correctly in explicit type conversions. PR12121.
llvm-svn: 151674
2012-02-29 00:00:28 +00:00