Commit Graph

1873 Commits

Author SHA1 Message Date
Faisal Vali 936de9d666 [c++2a] [concepts] Add rudimentary parsing support for template concept declarations
This patch is a tweak of changyu's patch: https://reviews.llvm.org/D40381. It differs in that the recognition of the 'concept' token is moved into the machinery that recognizes declaration-specifiers - this allows us to leverage the attribute handling machinery more seamlessly.

See the test file to get a sense of the basic parsing that this patch supports. 

There is much more work to be done before concepts are usable...

Thanks Changyu!

llvm-svn: 330794
2018-04-25 02:42:26 +00:00
Malcolm Parsons fab3680990 Clean carriage returns from lib/ and include/. NFC.
Summary:
Clean carriage returns from lib/ and include/. NFC.
(I have to make this change locally in order for `git diff` to show sane output after I edit a file, so I might as well ask for it to be committed. I don't have commit privs myself.)
(Without this patch, `git rebase`ing any change involving SemaDeclCXX.cpp is a real nightmare. :( So while I have no right to ask for this to be committed, geez would it make my workflow easier if it were.)

Here's the command I used to reformat things. (Requires bash and OSX/FreeBSD sed.)

    git grep -l $'\r' lib include | xargs sed -i -e $'s/\r//'
    find lib include -name '*-e' -delete

Reviewers: malcolm.parsons

Reviewed By: malcolm.parsons

Subscribers: emaste, krytarowski, cfe-commits

Differential Revision: https://reviews.llvm.org/D45591

Patch by Arthur O'Dwyer.

llvm-svn: 330112
2018-04-16 08:31:08 +00:00
Aaron Ballman 3399e50832 Correctly diagnose when a conversion function is declared with a type qualifier in the declaration specifiers rather than in the conversion type id. Fixes PR30595.
llvm-svn: 329924
2018-04-12 16:41:55 +00:00
Akira Hatanaka e6313ace66 [ObjC++] Never pass structs that transitively contain __weak fields in
registers.

This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.

This reapplies r329617. r329617 didn't specify the underlying type for
enum ArgPassingKind, which caused regression tests to fail on a windows
bot.

rdar://problem/39194693

Differential Revision: https://reviews.llvm.org/D45384

llvm-svn: 329635
2018-04-09 22:48:22 +00:00
Akira Hatanaka d236a34ddb Revert "[ObjC++] Never pass structs that transitively contain __weak fields in"
This reverts commit r329617. It broke a windows bot.

http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/16372/steps/test/logs/stdio

llvm-svn: 329627
2018-04-09 21:47:58 +00:00
Akira Hatanaka f15d29ccc7 [ObjC++] Never pass structs that transitively contain __weak fields in
registers.

This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.

rdar://problem/39194693

llvm-svn: 329617
2018-04-09 20:39:47 +00:00
Richard Smith 866dee4ea0 Add helper to determine if a field is a zero-length bitfield.
llvm-svn: 328999
2018-04-02 18:29:43 +00:00
Akira Hatanaka fcbe17c6be [ObjC++] Make parameter passing and function return compatible with ObjC
ObjC and ObjC++ pass non-trivial structs in a way that is incompatible
with each other. For example:
    
typedef struct {
  id f0;
  __weak id f1;
} S;
    
// this code is compiled in c++.
extern "C" {
  void foo(S s);
}
    
void caller() {
  // the caller passes the parameter indirectly and destructs it.
  foo(S());
}
    
// this function is compiled in c.
// 'a' is passed directly and is destructed in the callee.
void foo(S a) {
}
    
This patch fixes the incompatibility by passing and returning structs
with __strong or weak fields using the C ABI in C++ mode. __strong and
__weak fields in a struct do not cause the struct to be destructed in
the caller and __strong fields do not cause the struct to be passed
indirectly.
    
Also, this patch fixes the microsoft ABI bug mentioned here:
    
https://reviews.llvm.org/D41039?id=128767#inline-364710
    
rdar://problem/38887866
    
Differential Revision: https://reviews.llvm.org/D44908

llvm-svn: 328731
2018-03-28 21:13:14 +00:00
Richard Trieu b402580616 Fix some handling of AST nodes with diagnostics.
The diagnostic system for Clang can already handle many AST nodes.  Instead
of converting them to strings first, just hand the AST node directly to
the diagnostic system and let it handle the output.  Minor changes in some
diagnostic output.

llvm-svn: 328688
2018-03-28 04:16:13 +00:00
Richard Smith c660c8f5d2 Implement C++ DR727, which permits explicit specializations at class scope.
More generally, this permits a template to be specialized in any scope in which
it could be defined, so this also supersedes DR44 and DR374 (the latter of
which we previously only implemented in C++11 mode onwards due to unclarity as
to whether it was a DR).

llvm-svn: 327705
2018-03-16 13:36:56 +00:00
Stephan Bergmann 0feb0b9059 Propagate DLLAttr to friend re-declarations of member functions
...that have already been constructed (e.g., in inner classes) while parsing the
class definition.  They would otherwise lack any DLLAttr inherited from the
class, which are only set here (called from Sema::CheckCompletedClass) after the
class definition has been parsed completely.

Differential revision: https://reviews.llvm.org/D16632

llvm-svn: 326990
2018-03-08 07:34:40 +00:00
George Burgess IV 00f70bd933 Remove redundant casts. NFC
So I wrote a clang-tidy check to lint out redundant `isa`, `cast`, and
`dyn_cast`s for fun. This is a portion of what it found for clang; I
plan to do similar cleanups in LLVM and other subprojects when I find
time.

Because of the volume of changes, I explicitly avoided making any change
that wasn't highly local and obviously correct to me (e.g. we still have
a number of foo(cast<Bar>(baz)) that I didn't touch, since overloading
is a thing and the cast<Bar> did actually change the type -- just up the
class hierarchy).

I also tried to leave the types we were cast<>ing to somewhere nearby,
in cases where it wasn't locally obvious what we were dealing with
before.

llvm-svn: 326416
2018-03-01 05:43:23 +00:00
Hans Wennborg 83665e6d36 Re-commit r324991 "Fix for PR32992. Static const classes not exported."
Fix for PR32992. Static const classes not exported.

Patch by zahiraam!

(This re-lands the commit, but using S.MarkVariableReferenced instead of
S.PendingInstantiations.push_back, and with an additional test.)

Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 326089
2018-02-26 15:03:59 +00:00
Hans Wennborg 00f4598ec5 Revert r324991 "Fix for PR32992. Static const classes not exported."
This broke the Chromium build on Windows; see https://crbug.com/812231

> Fix for PR32992. Static const classes not exported.
>
> Patch by zahiraam!
>
> Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 325133
2018-02-14 15:19:46 +00:00
Hans Wennborg 3bd0a15867 Fix for PR32992. Static const classes not exported.
Patch by zahiraam!

Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 324991
2018-02-13 09:19:43 +00:00
Akira Hatanaka 02914dc127 Add support for attribute 'trivial_abi'.
The 'trivial_abi' attribute can be applied to a C++ class, struct, or
union. It makes special functions of the annotated class (the destructor
and copy/move constructors) to be trivial for the purpose of calls and,
as a result, enables the annotated class or containing classes to be
passed or returned using the C ABI for the underlying type.

When a type that is considered trivial for the purpose of calls despite
having a non-trivial destructor (which happens only when the class type
or one of its subobjects is a 'trivial_abi' class) is passed to a
function, the callee is responsible for destroying the object.

For more background, see the discussions that took place on the mailing
list:

http://lists.llvm.org/pipermail/cfe-dev/2017-November/055955.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180101/thread.html#214043

rdar://problem/35204524

Differential Revision: https://reviews.llvm.org/D41039

llvm-svn: 324269
2018-02-05 20:23:22 +00:00
Vedant Kumar a14a1f923f [Parse] Forward brace locations to TypeConstructExpr
When parsing C++ type construction expressions with list initialization,
forward the locations of the braces to Sema.

Without these locations, the code coverage pass crashes on the given test
case, because the pass relies on getLocEnd() returning a valid location.

Here is what this patch does in more detail:

  - Forwards init-list brace locations to Sema (ParseExprCXX),
  - Builds an InitializationKind with these locations (SemaExprCXX), and
  - Uses these locations for constructor initialization (SemaInit).

The remaining changes fall out of introducing a new overload for
creating direct-list InitializationKinds.

Testing: check-clang, and a stage2 coverage-enabled build of clang with
asserts enabled.

Differential Revision: https://reviews.llvm.org/D41921

llvm-svn: 322729
2018-01-17 18:53:51 +00:00
Jan Korous fda9daeb03 [Sema] Fix crash for type-dependent base classes
llvm-svn: 322438
2018-01-13 15:24:16 +00:00
Aaron Ballman a503855906 Track in the AST whether the operand to a UnaryOperator can overflow and then use that logic when evaluating constant expressions and emitting codegen.
llvm-svn: 322074
2018-01-09 13:07:03 +00:00
Richard Smith 50e291eaf2 Fix and simplify handling of return type for (generic) lambda conversion function to function pointer.
Previously, we would:
 * compute the type of the conversion function and static invoker as a
   side-effect of template argument deduction for a conversion
 * re-compute the type as part of deduced return type deduction when building
   the conversion function itself

Neither of these turns out to be quite correct. There are other ways to reach a
declaration of the conversion function than in a conversion (such as an
explicit call or friend declaration), and performing auto deduction causes the
function type to be rebuilt in the context of the lambda closure type (which is
different from the context in which it originally appeared, resulting in
spurious substitution failures for constructs that are valid in one context but
not the other, such as the use of an enclosing class's "this" pointer).

This patch switches us to use a different strategy: as before, we use the
declared type of the operator() to form the type of the conversion function and
invoker, but we now populate that type as part of return type deduction for the
conversion function. And the invoker is now treated as simply being an
implementation detail of building the conversion function, and isn't given
special treatment by template argument deduction for the conversion function
any more.

llvm-svn: 321683
2018-01-02 23:52:42 +00:00
Faisal Vali 090da2d1ac Again reverting an attempt to convert the DeclSpec enums into scoped enums.
- reverts r321622, r321625, and r321626.
  - the use of bit-fields is still resulting in warnings - even though we can use static-asserts to harden the code and ensure the bit-fields are wide enough.  The bots still complain of warnings being seen.
  - to silence the warnings requires specifying the bit-fields with the underlying enum type (as opposed to the enum type itself), which then requires lots of unnecessary static casts of each enumerator within DeclSpec to the underlying-type, which even though could be seen as implementation details, it does hamper readability - and given the additional litterings, makes me question the value of the change.

So in short - I give up (for now at least).  

Sorry about the noise.

llvm-svn: 321628
2018-01-01 18:23:28 +00:00
Faisal Vali 038df49033 [NFC] Modernize enums TypeSpecifierWidth, TypeSpecifierSign & TypeSpecifierType into scoped enums with underlying types.
- Since these enums are used as bit-fields - for the bit-fields to be interpreted as unsigned, the underlying type must be specified as unsigned.

Previous failed attempt - wherein I did not specify an underlying type - was the sum of:
https://reviews.llvm.org/rC321614
https://reviews.llvm.org/rC321615

llvm-svn: 321622
2018-01-01 15:42:13 +00:00
Faisal Vali c535adcfc5 Revert r321614 and r321615
- the enum changes to TypeSpecifierType are breaking some tests - and will require a more careful integration.

Sorry about rushing these changes - thought I could sneak them in prior to heading out for new years ;)

llvm-svn: 321616
2018-01-01 02:49:17 +00:00
Faisal Vali 8736dee017 [NFC] Modernize enums TypeSpecifierWidth, TypeSpecifierSign & TypeSpecifierType into scoped enums.
llvm-svn: 321614
2018-01-01 02:19:52 +00:00
Faisal Vali 2ab8c15cf1 [NFC] Modernize enum 'UnqualifiedId::IdKind' into a scoped enum UnqualifiedIdKind.
llvm-svn: 321574
2017-12-30 04:15:27 +00:00
Faisal Vali 421b2d1d8e [NFC] Modernize enum Declarator::TheContext to a type-safe scoped enum.
Note, we don't do any bitwise manipulations when using them.

llvm-svn: 321546
2017-12-29 05:41:00 +00:00
Benjamin Kramer 0742090e3d [AST] Inline CompoundStmt contents into the parent allocation.
Saves a pointer on every CompoundStmt.

llvm-svn: 321429
2017-12-24 16:24:20 +00:00
Adrian Prantl f3b3ccda59 Silence a bunch of implicit fallthrough warnings
llvm-svn: 321115
2017-12-19 22:06:11 +00:00
Benjamin Kramer acfa339e15 Refactor overridden methods iteration to avoid double lookups.
Convert most uses to range-for loops. No functionality change intended.

llvm-svn: 320954
2017-12-17 23:52:45 +00:00
Dimitry Andric c7bc461298 Don't trigger -Wuser-defined-literals for system headers
Summary:
In D41064, I proposed adding `#pragma clang diagnostic ignored
"-Wuser-defined-literals"` to some of libc++'s headers, since these
warnings are now triggered by clang's new `-std=gnu++14` default:

```
$ cat test.cpp
#include <string>

$ clang -std=c++14 -Wsystem-headers -Wall -Wextra -c test.cpp
In file included from test.cpp:1:
In file included from /usr/include/c++/v1/string:470:
/usr/include/c++/v1/string_view:763:29: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char> operator "" sv(const char *__str, size_t __len)
                            ^
/usr/include/c++/v1/string_view:769:32: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<wchar_t> operator "" sv(const wchar_t *__str, size_t __len)
                               ^
/usr/include/c++/v1/string_view:775:33: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char16_t> operator "" sv(const char16_t *__str, size_t __len)
                                ^
/usr/include/c++/v1/string_view:781:33: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string_view<char32_t> operator "" sv(const char32_t *__str, size_t __len)
                                ^
In file included from test.cpp:1:
/usr/include/c++/v1/string:4012:24: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char> operator "" s( const char *__str, size_t __len )
                       ^
/usr/include/c++/v1/string:4018:27: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
                          ^
/usr/include/c++/v1/string:4024:28: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
                           ^
/usr/include/c++/v1/string:4030:28: warning: user-defined literal suffixes not starting with '_' are reserved [-Wuser-defined-literals]
    basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
                           ^
8 warnings generated.
```

Both @aaron.ballman and @mclow.lists felt that adding this workaround to
the libc++ headers was the wrong way, and it should be fixed in clang
instead.

Here is a proposal to do just that.  I verified that this suppresses the
warning, even when -Wsystem-headers is used, and that the warning is
still emitted for a declaration outside of system headers.

Reviewers: aaron.ballman, mclow.lists, rsmith

Reviewed By: aaron.ballman

Subscribers: mclow.lists, aaron.ballman, andrew, emaste, cfe-commits

Differential Revision: https://reviews.llvm.org/D41080

llvm-svn: 320755
2017-12-14 22:32:24 +00:00
Zhihao Yuan c81f4538ec Allow conditions to be decomposed with structured bindings
Summary:
This feature was discussed but not yet proposed.  It allows a structured binding to appear as a //condition//

    if (auto [ok, val] = f(...))

So the user can save an extra //condition// if the statement can test the value to-be-decomposed instead.  Formally, it makes the value of the underlying object of the structured binding declaration also the value of a //condition// that is an initialized declaration.

Considering its logicality which is entirely evident from its trivial implementation, I think it might be acceptable to land it as an extension for now before I write the paper.

Reviewers: rsmith, faisalv, aaron.ballman

Reviewed By: rsmith

Subscribers: aaron.ballman, cfe-commits

Differential Revision: https://reviews.llvm.org/D39284

llvm-svn: 320011
2017-12-07 07:03:15 +00:00
Hubert Tong bd72cd9577 Remove old concepts parsing code
Summary:
This is so we can implement concepts per P0734R0. Relevant failing test
cases are disabled.

Reviewers: hubert.reinterpretcast, rsmith, saar.raz, nwilson

Reviewed By: saar.raz

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D40380

Patch by Changyu Li!

llvm-svn: 319992
2017-12-07 00:34:20 +00:00
Aaron Ballman c351fba69e Now that C++17 is official (https://www.iso.org/standard/68564.html), start changing the C++1z terminology over to C++17. NFC intended, these are all mechanical changes.
llvm-svn: 319688
2017-12-04 20:27:34 +00:00
Richard Trieu 7f932dd063 Change assertion to quick exit from checking function.
Remove the assertion that could be triggered by invalid code.  Replace it with
an early exit from the checking function.

llvm-svn: 317073
2017-11-01 03:57:27 +00:00
Reid Kleckner 2e87a21c7c [MS] Allow access to ambiguous, inaccessible direct bases
Summary:
Clang typically warns that in the following class hierarchy, 'A' is
inaccessible because there is no series of casts that the user can
write to access it unambiguously:
  struct A { };
  struct B : A { };
  struct C : A, B { };

MSVC allows the user to convert from C* to A*, though, and we've
encountered this issue in the latest Windows SDK headers.

This patch allows this conversion when -fms-compatibility is set and
adds a warning for it under -Wmicrosoft-inaccessible-base.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D39389

llvm-svn: 316807
2017-10-27 22:48:41 +00:00
Richard Smith 5b34958b46 Support for destroying operator delete, per C++2a proposal P0722.
This feature is not (yet) approved by the C++ committee, so this is liable to
be reverted or significantly modified based on committee feedback.

No functionality change intended for existing code (a new type must be defined
in namespace std to take advantage of this feature).

llvm-svn: 315662
2017-10-13 01:55:36 +00:00
Erich Keane 883f22ef7e [Sema][Crash] Correctly handle an non-dependent noexcept expr in function template
It seems that all of the other templated cases are handled correctly,
however the function template case was not correctly handled. This
patch recovers from this condition by setting the function to noexcept
after diagnosing. Previously it simply set NoexceptExpr to null,
which caused an Assert when this was evaluated during substitution.

Differential Revision:https://reviews.llvm.org/D38700

llvm-svn: 315638
2017-10-12 23:01:53 +00:00
Richard Smith becb92dec8 [Modules TS] Module ownership semantics for redeclarations.
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.

This reinstates r315251 and r315256, reverted in r315309 and r315308
respectively, tweaked to avoid triggering a linkage calculation when declaring
implicit special members (this exposed our pre-existing issue with typedef
names for linkage changing the linkage of types whose linkage has already been
computed and cached in more cases). A testcase for that regression has been
added in r315366.

llvm-svn: 315379
2017-10-10 22:33:17 +00:00
Eric Liu f01516db8d Revert "[Modules TS] Module ownership semantics for redeclarations."
This reverts commit r315251. See the original commit thread for reason.

llvm-svn: 315309
2017-10-10 13:09:40 +00:00
Richard Smith b87720b77a [Modules TS] Module ownership semantics for redeclarations.
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.

llvm-svn: 315251
2017-10-09 23:42:09 +00:00
Richard Smith 81df9eb0f2 PR33839: Fix -Wunused handling for structured binding declarations.
We warn about a structured binding declaration being unused only if none of its
bindings are used.

llvm-svn: 314733
2017-10-02 22:43:36 +00:00
Erich Keane 97dfc4ab28 [Sema] Correct nothrow inherited by noexcept
As reported in https://bugs.llvm.org/show_bug.cgi?id=33235,
a noexcept function was unable to inherit from a nothrow defaulted
constructor. Attribute "nothrow" is supposed to be semantically
identical to noexcept, and in fact, a number of other places in the
code treat them identically.

This patch simply checks the RecordDecl for the correct attribute in
the case where no other exception specifier was set.

Differential Revision: https://reviews.llvm.org/D38209

llvm-svn: 314462
2017-09-28 20:47:10 +00:00
Nico Weber b688d131f0 Consolidate std::move() detection code. No behavior change.
llvm-svn: 314427
2017-09-28 16:16:39 +00:00
Richard Smith c95d2c5dda Give external linkage and mangling to lambdas inside inline variables and variable templates.
This implements the proposed approach in https://github.com/itanium-cxx-abi/cxx-abi/issues/33

This reinstates r313827, reverted in r313856, with a fix for the 'out-of-bounds
enumeration value' ubsan error in that change.

llvm-svn: 313955
2017-09-22 04:25:05 +00:00
Akira Hatanaka 98a49337be Add support for attribute 'noescape'.
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.

This recommits r313722, which was reverted in r313725 because clang
couldn't build compiler-rt. It failed to build because there were
function declarations that were missing 'noescape'. That has been fixed
in r313929.

rdar://problem/19886775

Differential Revision: https://reviews.llvm.org/D32210

llvm-svn: 313945
2017-09-22 00:41:05 +00:00
Vitaly Buka 17def21749 Revert "Give external linkage and mangling to lambdas inside inline variables and variable templates."
To fix: runtime error: load of value 15, which is not a valid value for type 'clang::LVComputationKind'

This reverts commit r313827.

llvm-svn: 313856
2017-09-21 02:51:56 +00:00
Erich Keane bb8636477d [MS Compat]Allow __interfaces to have properties.
__interface types are allowed in MSVC to have "property" data members
(marked with declspec property). This patch alters Sema to allow property
data members.

Differential Revision: https://reviews.llvm.org/D38092

llvm-svn: 313828
2017-09-20 22:28:24 +00:00
Richard Smith fb130c6084 Give external linkage and mangling to lambdas inside inline variables and variable templates.
This implements the proposed approach in https://github.com/itanium-cxx-abi/cxx-abi/issues/33

llvm-svn: 313827
2017-09-20 22:17:55 +00:00
Akira Hatanaka 30c93dba5b Revert "Add support for attribute 'noescape'."
This reverts commit r313722.

It looks like compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc cannot be
compiled because some of the functions declared in the file do not match
the ones in the SDK headers (which are annotated with 'noescape').

llvm-svn: 313725
2017-09-20 06:55:43 +00:00
Akira Hatanaka e974479fa5 Add support for attribute 'noescape'.
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.

rdar://problem/19886775

Differential Revision: https://reviews.llvm.org/D32210

llvm-svn: 313722
2017-09-20 06:32:45 +00:00