Commit Graph

32 Commits

Author SHA1 Message Date
Sean Fertile d900dd0c23 Revert "[CodeGenCXX] Treat 'this' as noalias in constructors"
This reverts commit https://reviews.llvm.org/rL344150 which causes
MachineOutliner related failures on the ppc64le multistage buildbot.

llvm-svn: 344526
2018-10-15 15:43:00 +00:00
Anton Bikineev cc7e74753a [CodeGenCXX] Treat 'this' as noalias in constructors
This is currently a clang extension and a resolution
of the defect report in the C++ Standard.

Differential Revision: https://reviews.llvm.org/D46441

llvm-svn: 344150
2018-10-10 16:14:51 +00:00
Akira Hatanaka 8e57b07f66 Distinguish `__block` variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

This reapplies r343518 after fixing a use-after-free bug in function
Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after
it was popped and deleted.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 343542
2018-10-01 21:51:28 +00:00
Akira Hatanaka 3197484701 Revert r343518.
Bots are still failing.

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/24420
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/12958

llvm-svn: 343531
2018-10-01 20:29:34 +00:00
Akira Hatanaka 2bf09ccfd5 Distinguish `__block` variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

This reapplies r341754, which was reverted in r341757 because it broke a
couple of bots. r341754 was calling markEscapingByrefs after the call to
PopFunctionScopeInfo, which caused the popped function scope to be
cleared out when the following code was compiled, for example:

$ cat test.m
struct A {
  id data[10];
};

void foo() {
  __block A v;
  ^{ (void)v; };
}

This commit calls markEscapingByrefs before calling PopFunctionScopeInfo
to prevent that from happening.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 343518
2018-10-01 18:50:14 +00:00
Akira Hatanaka 9bd2452708 Revert r341754.
The commit broke a couple of bots:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/12347
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/7310

llvm-svn: 341757
2018-09-09 05:22:49 +00:00
Akira Hatanaka 2e00b98027 Distinguish `__block` variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 341754
2018-09-08 20:03:00 +00:00
Akira Hatanaka 2ec36f08a6 [CodeGen] Merge identical block descriptor global variables.
Currently, clang generates a new block descriptor global variable for
each new block literal. This commit merges block descriptors that are
identical inside and across translation units using the same approach
taken in r339438.

To enable merging identical block descriptors, the size and signature of
the block and information about the captures are encoded into the name
of the block descriptor variable. Also, the block descriptor variable is
marked as linkonce_odr and unnamed_addr.

rdar://problem/42640703

Differential Revision: https://reviews.llvm.org/D50783

llvm-svn: 340041
2018-08-17 15:46:07 +00:00
Akira Hatanaka 9978da3615 [CodeGen] Merge equivalent block copy/helper functions.
Clang generates copy and dispose helper functions for each block literal
on the stack. Often these functions are equivalent for different blocks.
This commit makes changes to merge equivalent copy and dispose helper
functions and reduce code size.

To enable merging equivalent copy/dispose functions, the captured object
infomation is encoded into the helper function name. This allows IRGen
to check whether an equivalent helper function has already been emitted
and reuse the function instead of generating a new helper function
whenever a block is defined. In addition, the helper functions are
marked as linkonce_odr to enable merging helper functions that have the
same name across translation units and marked as unnamed_addr to enable
the linker's deduplication pass to merge functions that have different
names but the same content.

rdar://problem/42640608

Differential Revision: https://reviews.llvm.org/D50152

llvm-svn: 339438
2018-08-10 15:09:24 +00:00
Adrian Prantl e8dd2bd834 Fix C++ testcase I forgot to add to r316689.
llvm-svn: 316695
2017-10-26 20:16:03 +00:00
David Blaikie a953f2825b Update Clang tests to handle explicitly typed load changes in LLVM.
llvm-svn: 230795
2015-02-27 21:19:58 +00:00
David Blaikie 218b783192 Update Clang tests to handle explicitly typed gep changes in LLVM.
llvm-svn: 230783
2015-02-27 19:18:17 +00:00
David Blaikie 4e0ccd1a48 Update test to be ready for typeless pointer changes
llvm-svn: 229270
2015-02-15 04:12:16 +00:00
Hal Finkel a2347baaec Mark C++ reference parameters as dereferenceable
Because references must be initialized using some evaluated expression, they
must point to something, and a callee can assume the reference parameter is
dereferenceable. Taking advantage of a new attribute just added to LLVM, mark
them as such.

Because dereferenceability in addrspace(0) implies nonnull in the backend, we
don't need both attributes. However, we need to know the size of the object to
use the dereferenceable attribute, so for incomplete types we still emit only
nonnull.

llvm-svn: 213386
2014-07-18 15:52:10 +00:00
Nick Lewycky 9b46eb8112 Add 'nonnull' parameter or return attribute when producing an llvm pointer type in a function type where the C++ type is a reference. Update the tests.
llvm-svn: 209723
2014-05-28 09:56:42 +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
Adrian Prantl 0f6df00e4d Bugfix/Followup for r177086.
* Store the .block_descriptor (instead of self) in the alloca so we
  can guarantee that all captured variables are available at -O0.
* Add the missing OpDeref for the alloca.
rdar://problem/12767564

llvm-svn: 178361
2013-03-29 19:20:35 +00:00
John McCall eaef89b197 Fix a crash-on-valid where a block capture copy expression was
picking up cleanups from earlier in the statement.  Also fix a
crash-on-invalid where a reference to an invalid decl from an
enclosing scope was causing an expression to fail to build, but
only *after* a cleanup was registered from that statement,
causing an assertion downstream.

The crash-on-valid is rdar://13459289.

llvm-svn: 177692
2013-03-22 02:10:40 +00:00
Adrian Prantl 51936dd0bc Allocate stack storage for .block_descriptor and captured self at -O0.
This way the register allocator will not optimize away the debug info
for captured variables.

Fixes rdar://problem/12767564

llvm-svn: 177086
2013-03-14 17:53:33 +00:00
Fariborz Jahanian 6362803cfe block literal irgen: several improvements on naming block
literal helper functions. All helper functions (global
and locals) use block_invoke as their prefix. Local literal
helper names are prefixed by their enclosing mangled function
names. Blocks in non-local initializers (e.g. a global variable 
or a C++11 field) are prefixed by their mangled variable name. 
The descriminator number added to end of the name starts off 
with blank (for first block) and _<N> (for the N+2-th block).

llvm-svn: 159206
2012-06-26 16:06:38 +00:00
Douglas Gregor 3a08c1cd3b Two minor, related fixes for template instantiation with blocks:
- Make sure that the block expression is instantiation-dependent if the
    block is in a dependent context
  - Make sure that the C++ 'this' expression gets captured even if we
  don't rebuild the AST node during template instantiation. This would
  also have manifested as a bug for lambdas.

Fixes <rdar://problem/10832617>.

llvm-svn: 151372
2012-02-24 17:41:38 +00:00
Richard Smith dafff94759 constexpr irgen: Add irgen support for APValue::Struct, APValue::Union,
APValue::Array and APValue::MemberPointer. All APValue values can now be emitted
as constants.

Add new CGCXXABI entry point for emitting an APValue MemberPointer. The other
entrypoints dealing with constant member pointers are no longer necessary and
will be removed in a later change.

Switch codegen from using EvaluateAsRValue/EvaluateAsLValue to
VarDecl::evaluateValue. This performs caching and deals with the nasty cases in
C++11 where a non-const object's initializer can refer indirectly to
previously-initialized fields within the same object.

Building the intermediate APValue object incurs a measurable performance hit on
pathological testcases with huge initializer lists, so we continue to build IR
directly from the Expr nodes for array and record types outside of C++11.

llvm-svn: 148178
2012-01-14 04:30:29 +00:00
John McCall f1a3c2aee1 Be sure to insulate block literals from any cleanups in their
enclosing full-expressions.  It is somewhat amazing that 
this hasn't come up as a problem before.

llvm-svn: 144362
2011-11-11 03:19:12 +00:00
John McCall f4beacd059 Whenever explicitly activating or deactivating a cleanup, we
need to provide a 'dominating IP' which is guaranteed to
dominate the (de)activation point but which cannot be avoided
along any execution path from the (de)activation point to
the push-point of the cleanup.  Using the entry block is
bad mojo.

llvm-svn: 144276
2011-11-10 10:43:54 +00:00
John McCall e63abb5d2b Fix a subtle bug with cleanups: when activating
a previously-inactive cleanup, not only do we need a
flag variable, but we should also force the cleanup to
query the flag variable.  However, we only need to do
this when we're activating in a context that's
conditionally executed;  otherwise, we may safely
assume that the cleanup is dominated by the activation
point.

llvm-svn: 144271
2011-11-10 09:22:44 +00:00
John McCall 7d92c70e6f Somehow I fouled up this test.
llvm-svn: 137882
2011-08-17 22:04:02 +00:00
John McCall 75f92b519c Gather cleanups correctly in block return statements.
Thanks to Ted for finding this with magic tools.

llvm-svn: 137877
2011-08-17 21:34:14 +00:00
Chris Lattner a5f58b05e8 clang side to match the LLVM IR type system rewrite patch.
llvm-svn: 134831
2011-07-09 17:41:47 +00:00
John McCall a85af56e66 When block-capturing a variable with a non-trivial destructor,
make sure to mark the destructor.  This normally isn't required,
because the destructor should have been marked as part of the
declaration of the local, but it's necessary when the variable
is a parameter because it's the call sites that are responsible
for those destructors.

llvm-svn: 130372
2011-04-28 02:15:35 +00:00
John McCall f9b056b002 After much contemplation, I've decided that we probably shouldn't "unique"
__block object copy/dispose helpers for C++ objects with those for
different variables with completely different semantics simply because
they happen to both be no more aligned than a pointer.

Found by inspection.

Also, internalize most of the helper generation logic within CGBlocks.cpp,
and refactor it to fit my peculiar aesthetic sense.

llvm-svn: 128618
2011-03-31 08:03:29 +00:00
John McCall b0a3ecb41c Extend the const capture optimization to C++ record types with no
mutable fields and with trivial destructors and copy constructors.

llvm-svn: 125073
2011-02-08 03:07:00 +00:00
John McCall 93be3f75cc When copy-capturing values for a nested capture, use a BlockDeclRefExpr.
llvm-svn: 125021
2011-02-07 18:37:40 +00:00