Commit Graph

2920 Commits

Author SHA1 Message Date
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
Richard Smith
5159bbad8b PR38627: Fix handling of exception specification adjustment for
destructors.

We previously tried to patch up the exception specification after
completing the class, which went wrong when the exception specification
was needed within the class body (in particular, by a friend
redeclaration of the destructor in a nested class). We now mark the
destructor as having a not-yet-computed exception specification
immediately after creating it.

This requires delaying various checks against the exception
specification (where we'd previously have just got the wrong exception
specification, and now find we have an exception specification that we
can't compute yet) when those checks fire while the class is being
defined.

This also exposed an issue that we were missing a CodeSynthesisContext
for computation of exception specifications (otherwise we'd fail to make
the module containing the definition of the class visible when computing
its members' exception specs). Adding that incidentally also gives us a
diagnostic quality improvement.

This has also exposed an pre-existing problem: making the exception
specification evaluation context a non-SFINAE context (as it should be)
results in a bootstrap failure; PR38850 filed for this.

llvm-svn: 341499
2018-09-05 22:30:37 +00:00
Richard Smith
e43e2b3667 Model type attributes as regular Attrs.
Specifically, AttributedType now tracks a regular attr::Kind rather than
having its own parallel Kind enumeration, and AttributedTypeLoc now
holds an Attr* instead of holding an ad-hoc collection of Attr fields.

Differential Revision: https://reviews.llvm.org/D50526

This reinstates r339623, reverted in r339638, with a fix to not fail
template instantiation if we instantiate a QualType with no associated
type source information and we encounter an AttributedType.

llvm-svn: 340215
2018-08-20 21:47:29 +00:00
Reid Kleckner
11f9f8acde Revert r339623 "Model type attributes as regular Attrs."
This breaks compiling atlwin.h in Chromium. I'm sure the code is invalid
in some way, but we put a lot of work into accepting it, and I'm sure
rejecting it was not an intended consequence of this refactoring. :)

llvm-svn: 339638
2018-08-14 01:55:37 +00:00
Richard Smith
f79178635a Model type attributes as regular Attrs.
Specifically, AttributedType now tracks a regular attr::Kind rather than
having its own parallel Kind enumeration, and AttributedTypeLoc now
holds an Attr* instead of holding an ad-hoc collection of Attr fields.

Differential Revision: https://reviews.llvm.org/D50526

llvm-svn: 339623
2018-08-13 22:07:09 +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
Stephen Kelly
a93380db84 Remove obsolete set call
Summary:
Case case of the switch statement here makes the same call, but it is
already done at the start of the function.

Reviewers: rsmith, dblaikie

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D50409

llvm-svn: 339402
2018-08-09 22:44:03 +00:00
Stephen Kelly
1c301dcbc4 Port getLocEnd -> getEndLoc
Reviewers: teemperor!

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D50351

llvm-svn: 339386
2018-08-09 21:09:38 +00:00
Stephen Kelly
f2ceec4811 Port getLocStart -> getBeginLoc
Reviewers: teemperor!

Subscribers: jholewinski, whisperity, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D50350

llvm-svn: 339385
2018-08-09 21:08:08 +00:00
Erich Keane
44bacdfcaf Implement diagnostic stream operator for ParsedAttr.
As a part of attempting to clean up the way attributes are 
printed, this patch adds an operator << to the diagnostics/
partialdiagnostics so that ParsedAttr can be sent directly.

This patch also rewrites a large amount* of the times when
ParsedAttr was printed using its IdentifierInfo object instead
of being printed itself.  
*"a large amount" == "All I could find".

llvm-svn: 339344
2018-08-09 13:21:32 +00:00
Nicolas Lesser
e19e5a69b3 Fold two cast plus a cast in a loop into a variable.
This avoids to recast `Record` multiple times.

llvm-svn: 338801
2018-08-03 01:24:52 +00:00
Richard Smith
1dd9501b3a Work around GCC miscompile exposed by r338464.
See gcc.gnu.org/PR86769 for details of the bug.

llvm-svn: 338478
2018-08-01 02:27:18 +00:00
Richard Smith
c4581f4e92 Speculative fix for buildbot failures after r338464.
llvm-svn: 338473
2018-08-01 01:57:49 +00:00
Richard Smith
f4e248c23e [P0936R0] add [[clang::lifetimebound]] attribute
This patch adds support for a new attribute, [[clang::lifetimebound]], that
indicates that the lifetime of a function result is related to one of the
function arguments. When walking an initializer to make sure that the lifetime
of the initial value is at least as long as the lifetime of the initialized
object, we step through parameters (including the implicit object parameter of
a non-static member function) that are marked with this attribute.

There's nowhere to write an attribute on the implicit object parameter, so in
lieu of that, it may be applied to a function type (where it appears
immediately after the cv-qualifiers and ref-qualifier, which is as close to a
declaration of the implicit object parameter as we have). I'm currently
modeling this in the AST as the attribute appertaining to the function type.

Differential Revision: https://reviews.llvm.org/D49922

llvm-svn: 338464
2018-08-01 00:33:25 +00:00
Alexey Sotkin
9d1ee0acfb [OpenCL] Forbid size dependent types used as kernel arguments
Summary:
Size_t, intptr_t, uintptr_t and ptrdiff_t cannot be used as kernel
arguments, according to OpenCL Specification s6.9k:
The size in bytes of these types are implementation-defined and in
addition can also be different for the OpenCL device and the host
processor making it difficult to allocate buffer objects to be passed
as arguments to a kernel declared as pointer to these types.

Patch by: Andrew Savonichev

Reviewers: Anastasia, yaxunl

Subscribers: yaxunl, Anastasia, cfe-commits

Differential Revision: https://reviews.llvm.org/D49725

llvm-svn: 338432
2018-07-31 20:26:43 +00:00
Alexey Sotkin
3b238ed662 [OpenCL] Check for invalid kernel arguments in array types
Summary:
OpenCL specification forbids use of several types as kernel arguments.
This patch improves existing diagnostic to look through arrays.

Patch by: Andrew Savonichev

Reviewers: Anastasia, yaxunl

Subscribers: yaxunl, Anastasia, cfe-commits

Differential Revision: https://reviews.llvm.org/D49723

llvm-svn: 338427
2018-07-31 19:47:19 +00:00
Fangrui Song
6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Yaxun Liu
a4005e13f7 [CUDA][HIP] Allow function-scope static const variable
CUDA 8.0 E.3.9.4 says: Within the body of a __device__ or __global__
function, only __shared__ variables or variables without any device
memory qualifiers may be declared with static storage class.

It is unclear how a function-scope non-const static variable
without device memory qualifier is implemented, therefore only static
const variable without device memory qualifier is allowed, which
can be emitted as a global variable in constant address space.

Currently clang only allows function-scope static variable with
__shared__ qualifier.

This patch also allows function-scope static const variable without
device memory qualifier and emits it as a global variable in constant
address space.

Differential Revision: https://reviews.llvm.org/D49931

llvm-svn: 338188
2018-07-28 03:05:25 +00:00
Erich Keane
c764e9a87e Update to -r337585, allow scoped enum inits in -pedantic
llvm-svn: 337738
2018-07-23 21:08:13 +00:00
Erich Keane
3efe00206f Implement cpu_dispatch/cpu_specific Multiversioning
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.

This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.

This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.

The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.

Differential Revision: https://reviews.llvm.org/D47474

llvm-svn: 337552
2018-07-20 14:13:28 +00:00
Erich Keane
7963e8bebb Add support for __declspec(code_seg("segname"))
This patch uses CodeSegAttr to represent __declspec(code_seg) rather than 
building on the existing support for #pragma code_seg.
The code_seg declspec is applied on functions and classes. This attribute 
enables the placement of code into separate named segments, including compiler-
generated codes and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

This patch fixes the regression for the support for attribute ((section).
746b78de78

Patch by Soumi Manna (Manna)
Differential Revision: https://reviews.llvm.org/D48841

llvm-svn: 337420
2018-07-18 20:04:48 +00:00
Erich Keane
e891aa971a [NFC] Rename clang::AttributeList to clang::ParsedAttr
Since The type no longer contains the 'next' item anymore, it isn't a list,
so rename it to ParsedAttr to be more accurate.

llvm-svn: 337005
2018-07-13 15:07:47 +00:00
Erich Keane
c480f30580 AttributeList de-listifying:
Basically, "AttributeList" loses all list-like mechanisms, ParsedAttributes is
switched to use a TinyPtrVector (and a ParsedAttributesView is created to
have a non-allocating attributes list). DeclaratorChunk gets the later kind,
Declarator/DeclSpec keep ParsedAttributes.

Iterators are added to the ParsedAttribute types so that for-loops work.

llvm-svn: 336945
2018-07-12 21:09:05 +00:00
Erich Keane
7481f75d76 [NFC] Replace usage of QualType.getTypePtr()-> with operator->
llvm-svn: 336836
2018-07-11 19:09:21 +00:00
Taiju Tsuiki
3be68e162f Revert r335019 "Update NRVO logic to support early return (Attempt 2)"
llvm-svn: 335022
2018-06-19 05:35:30 +00:00
Taiju Tsuiki
b000a8860e Update NRVO logic to support early return (Attempt 2)
Summary:
This is the second attempt of r333500 (Update NRVO logic to support early return).
The previous one was reverted for a miscompilation for an incorrect NRVO set up on templates such as:
```
struct Foo {};

template <typename T>
T bar() {
  T t;
  if (false)
    return T();
  return t;
}
```

Where, `t` is marked as non-NRVO variable before its instantiation. However, while its instantiation, it's left an NRVO candidate, turned into an NRVO variable later.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D47586

llvm-svn: 335019
2018-06-19 04:39:07 +00:00
Artem Belevich
e9fa53a09b [CUDA] Check initializers of instantiated template variables.
We were already performing checks on non-template variables,
but the checks on templated ones were missing.

Differential Revision: https://reviews.llvm.org/D45231

llvm-svn: 334143
2018-06-06 22:37:25 +00:00
Jan Korous
67da1257ee [Sema] Fix parsing of anonymous union in language linkage specification
C++17 [dcl.link]p4:
A linkage specification does not establish a scope.

C++17 [class.union.anon]p2:
Namespace level anonymous unions shall be declared static.

Differential Revision: https://reviews.llvm.org/D45884

rdar://problem/37545925

llvm-svn: 334062
2018-06-06 05:16:34 +00:00
Joel E. Denny
857613bc6d [AST] Fix loss of enum forward decl from decl context
For example, given:

  enum __attribute__((deprecated)) T *p;

-ast-print produced:

  enum T *p;

The attribute was lost because the enum forward decl was lost.

Another example is the loss of enum forward decls from C++ namespaces
(in MS compatibility mode).

The trouble was that the EnumDecl node was suppressed, as revealed by
-ast-dump.  The suppression of the EnumDecl was intentional in
r116122, but I don't understand why.  The suppression isn't needed for
the test suite to behave.

Reviewed by: rsmith

Differential Revision: https://reviews.llvm.org/D46846

llvm-svn: 333574
2018-05-30 18:33:53 +00:00
Sam McCall
5429bd751c Revert "Update NRVO logic to support early return"
This reverts commit r333500, which causes stage2 compiler crashes.

llvm-svn: 333547
2018-05-30 14:14:58 +00:00
Ilya Biryukov
28f048af9d [Sema] Don't skip function bodies with 'auto' without trailing return type
Summary:
Skipping them was clearly not intentional. It's impossible to
guarantee correctness if the bodies are skipped.
Also adds a test case for r327504, now that it does not produce
invalid errors that made the test fail.

Reviewers: aaron.ballman, sammccall, rsmith

Reviewed By: rsmith

Subscribers: rayglover-ibm, rwols, cfe-commits

Differential Revision: https://reviews.llvm.org/D44480

llvm-svn: 333538
2018-05-30 12:50:48 +00:00
Taiju Tsuiki
44f9c585b9 Update NRVO logic to support early return
Summary:
The previous implementation misses an opportunity to apply NRVO (Named Return Value
Optimization) below. That discourages user to write early return code.

```
struct Foo {};

Foo f(bool b) {
  if (b)
    return Foo();
  Foo oo;
  return oo;
}
```
That is, we can/should apply RVO for a local variable if:
 * It's directly returned by at least one return statement.
 * And, all reachable return statements in its scope returns the variable directly.
While, the previous implementation disables the RVO in a scope if there are multiple return
statements that refers different variables.

On the new algorithm, local variables are in NRVO_Candidate state at first, and a return
statement changes it to NRVO_Disabled for all visible variables but the return statement refers.
Then, at the end of the function AST traversal, NRVO is enabled for variables in NRVO_Candidate
state and refers from at least one return statement.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: xbolva00, Quuxplusone, arthur.j.odwyer, cfe-commits

Differential Revision: https://reviews.llvm.org/D47067

llvm-svn: 333500
2018-05-30 03:53:16 +00:00
Richard Trieu
e69acc5d8f Check pointer null-ness before dereferencing it.
-Warc-repeated-use-of-weak may trigger a segmentation fault when the Decl
being checked is outside of a function scope, leaving the current function
info pointer null.  This adds a check before using the function info.

llvm-svn: 333471
2018-05-29 22:43:00 +00:00
Momchil Velikov
fe76b36ab1 [Sema] Fix incorrect packed aligned structure layout
Handle attributes before checking the record layout (e.g. underalignment check
during `alignas` processing), as layout may be cached without taking into
account attributes that may affect it.

Differential Revision: https://reviews.llvm.org/D46439

llvm-svn: 332843
2018-05-21 14:28:43 +00:00
Richard Smith
fb50dd34ed Revert r332470 (and corresponding tests in r332492).
This regressed our support for __attribute__((section)). See added test file
for example of code broken by this.

llvm-svn: 332760
2018-05-18 20:18:17 +00:00
Erich Keane
64144eb194 Add support for __declspec(code_seg("segname"))
Add support for __declspec(code_seg("segname"))

This patch is built on the existing support for #pragma code_seg. The code_seg
declspec is allowed on functions and classes. The attribute enables the
placement of code into separate named segments, including compiler-generated
members and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

A new CodeSeg attribute is used instead of adding a new spelling to the existing
Section attribute since they don’t apply to the same Subjects. Section
attributes are also added for the code_seg declspec since they are used for
#pragma code_seg. No CodeSeg attributes are added to the AST.

The patch is written to match with the Microsoft compiler’s behavior even where
that behavior is a little complicated (see https://reviews.llvm.org/D22931, the
Microsoft feedback page is no longer available since MS has removed the page).
That code is in getImplicitSectionAttrFromClass routine.

Diagnostics messages are added to match with the Microsoft compiler for code-seg
attribute mismatches on base and derived classes and virtual overrides.


Differential Revision: https://reviews.llvm.org/D43352

llvm-svn: 332470
2018-05-16 13:57:17 +00:00
Richard Smith
d699da427a PR37450: Fix bug that disabled some type checks for variables with deduced types.
Also improve diagnostic for the case where a type is non-literal because it's a lambda.

llvm-svn: 332286
2018-05-14 20:15:04 +00:00
Sven van Haastregt
2ca6ba1045 [OpenCL] Restrict various keywords in OpenCL C++ mode
Restrict the following keywords in the OpenCL C++ language mode,
according to Sections 2.2 & 2.9 of the OpenCL C++ 1.0 Specification.

 - dynamic_cast
 - typeid
 - register (already restricted in OpenCL C, update the diagnostic)
 - thread_local
 - exceptions (try/catch/throw)
 - access qualifiers read_only, write_only, read_write

Support the `__global`, `__local`, `__constant`, `__private`, and
`__generic` keywords in OpenCL C++.  Leave the unprefixed address
space qualifiers such as global available, i.e., do not mark them as
reserved keywords in OpenCL C++.  libclcxx provides explicit address
space pointer classes such as `global_ptr` and `global<T>` that are
implemented using the `__`-prefixed qualifiers.

Differential Revision: https://reviews.llvm.org/D46022

llvm-svn: 331874
2018-05-09 13:16:17 +00:00
Adrian Prantl
9fc8faf9e6 Remove \brief commands from doxygen comments.
This is similar to the LLVM change https://reviews.llvm.org/D46290.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
2018-05-09 01:00:01 +00:00
Richard Smith
eaf11ad709 Track the result of evaluating a computed noexcept specification on the
FunctionProtoType.

We previously re-evaluated the expression each time we wanted to know whether
the type is noexcept or not. We now evaluate the expression exactly once.

This is not quite "no functional change": it fixes a crasher bug during AST
deserialization where we would try to evaluate the noexcept specification in a
situation where we have not deserialized sufficient portions of the AST to
permit such evaluation.

llvm-svn: 331428
2018-05-03 03:58:32 +00:00
Richard Smith
3a8244df6f Implement P0482R2, support for char8_t type.
This is not yet part of any C++ working draft, and so is controlled by the flag
-fchar8_t rather than a -std= flag. (The GCC implementation is controlled by a
flag with the same name.)

This implementation is experimental, and will be removed or revised
substantially to match the proposal as it makes its way through the C++
committee.

llvm-svn: 331244
2018-05-01 05:02:45 +00:00
Stuart Brady
a38f573ad0 Test commit removing trailing whitespace
llvm-svn: 331053
2018-04-27 16:11:56 +00:00
Richard Smith
53cb831172 Revert addition of 'concept' to diagnostics in r330890.
Matches revert in r330888 of r330794.

llvm-svn: 330891
2018-04-26 01:16:08 +00:00
Richard Smith
ecad88d2bb Factor out common code for diagnosing missing template arguments.
In passing, add 'concept' to the list of template kinds in diagnostics.

llvm-svn: 330890
2018-04-26 01:08:00 +00:00
Faisal Vali
a534f07f8c Revert rC330794 and some dependent tiny bug fixes
See Richard's humbling feedback here: 
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226482.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226486.html

Wish I'd had the patience to solicit the feedback prior to committing :)

Sorry for the noise guys.

Thank you Richard for being the steward that clang deserves!

llvm-svn: 330888
2018-04-26 00:42:40 +00:00
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
Yaxun Liu
887c569bcb [HIP] Add hip input kind and codegen for kernel launching
HIP is a language similar to CUDA (https://github.com/ROCm-Developer-Tools/HIP/blob/master/docs/markdown/hip_kernel_language.md ).
The language syntax is very similar, which allows a hip program to be compiled as a CUDA program by Clang. The main difference
is the host API. HIP has a set of vendor neutral host API which can be implemented on different platforms. Currently there is open source
implementation of HIP runtime on amdgpu target (https://github.com/ROCm-Developer-Tools/HIP).

This patch adds support of input kind and language standard hip.

When hip file is compiled, both LangOpts.CUDA and LangOpts.HIP is turned on. This allows compilation of hip program as CUDA
in most cases and only special handling of hip program is needed LangOpts.HIP is checked.

This patch also adds support of kernel launching of HIP program using HIP host API.

When -x hip is not specified, there is no behaviour change for CUDA.

Patch by Greg Rodgers.
Revised and lit test added by Yaxun Liu.

Differential Revision: https://reviews.llvm.org/D44984

llvm-svn: 330790
2018-04-25 01:10:37 +00:00
Steven Wu
3bb4aa566e [Availability] Improve availability to consider functions run at load time
Summary:
There are some functions/methods that run when the application launches
or the library loads. Those functions will run reguardless the OS
version as long as it satifies the minimum deployment target. Annotate
them with availability attributes doesn't really make sense because they
are essentially available on all targets since minimum deployment
target.

rdar://problem/36093384

Reviewers: arphaman, erik.pilkington

Reviewed By: erik.pilkington

Subscribers: erik.pilkington, cfe-commits

Differential Revision: https://reviews.llvm.org/D45699

llvm-svn: 330166
2018-04-16 23:34:18 +00:00
Erich Keane
41af971375 Limit types of builtins that can be redeclared.
As reported here: https://bugs.llvm.org/show_bug.cgi?id=37033
Any usage of a builtin function that uses a va_list by reference
will cause an assertion when redeclaring it.

After discussion in the review, it was concluded that the correct
way of accomplishing this fix is to make attempts to redeclare certain
builtins an error. Unfortunately, doing this limitation for all builtins
is likely a breaking change, so this commit simply limits it to
types with custom type checking and those that take a reference.

Two tests needed to be updated to make this work.

Differential Revision: https://reviews.llvm.org/D45383

llvm-svn: 330160
2018-04-16 21:30:08 +00:00
Nico Weber
ade321e7dd Revert r329684 (and follow-ups 329693, 329714). See discussion on https://reviews.llvm.org/D43578.
llvm-svn: 329739
2018-04-10 18:53:28 +00:00