Commit Graph

400 Commits

Author SHA1 Message Date
Leonard Chan f921d85422 This diff includes changes for supporting the following types.
// Primary fixed point types
signed short _Accum s_short_accum;
signed _Accum s_accum;
signed long _Accum s_long_accum;
unsigned short _Accum u_short_accum;
unsigned _Accum u_accum;
unsigned long _Accum u_long_accum;

// Aliased fixed point types
short _Accum short_accum;
_Accum accum;
long _Accum long_accum;
This diff only allows for declaration of the fixed point types. Assignment and other operations done on fixed point types according to http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1169.pdf will be added in future patches. The saturated versions of these types and the equivalent _Fract types will also be added in future patches.

The tests included are for asserting that we can declare these types.

Fixed the test that was failing by not checking for dso_local on some
targets.

Differential Revision: https://reviews.llvm.org/D46084

llvm-svn: 333923
2018-06-04 16:07:52 +00:00
Leonard Chan 0d485dbb40 Revert "This diff includes changes for supporting the following types."
This reverts commit r333814, which fails for a test checking the bit
width on ubuntu.

llvm-svn: 333815
2018-06-02 03:27:13 +00:00
Leonard Chan db55d8331e This diff includes changes for supporting the following types.
```

// Primary fixed point types
signed short _Accum s_short_accum;
signed _Accum s_accum;
signed long _Accum s_long_accum;
unsigned short _Accum u_short_accum;
unsigned _Accum u_accum;
unsigned long _Accum u_long_accum;

// Aliased fixed point types
short _Accum short_accum;
_Accum accum;
long _Accum long_accum;

```

This diff only allows for declaration of the fixed point types. Assignment and other operations done on fixed point types according to http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1169.pdf will be added in future patches. The saturated versions of these types and the equivalent `_Fract` types will also be added in future patches.

The tests included are for asserting that we can declare these types.

Differential Revision: https://reviews.llvm.org/D46084

llvm-svn: 333814
2018-06-02 02:58:51 +00:00
Heejin Ahn 1eb074d76e [WebAssembly] Hide new Wasm EH behind its feature flag
Summary:
clang's current wasm EH implementation is a non-MVP feature in progress.
We had a `-mexception-handling` wasm feature but were not using it. This
patch hides the non-MVP wasm EH behind a flag, so it does not affect
other code for now.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, sunfish, cfe-commits

Differential Revision: https://reviews.llvm.org/D47614

llvm-svn: 333716
2018-06-01 01:01:37 +00:00
Heejin Ahn c647919933 [WebAssembly] Use Windows EH instructions for Wasm EH
Summary:
Because wasm control flow needs to be structured, using WinEH
instructions to support wasm EH brings several benefits. This patch
makes wasm EH uses Windows EH instructions, with some changes:
1. Because wasm uses a single catch block to catch all C++ exceptions,
   this merges all catch clauses into a single catchpad, within which we
   test the EH selector as in Itanium EH.
2. Generates a call to `__clang_call_terminate` in case a cleanup
   throws. Wasm does not have a runtime to handle this.
3. In case there is no catch-all clause, inserts a call to
   `__cxa_rethrow` at the end of a catchpad in order to unwind to an
   enclosing EH scope.

Reviewers: majnemer, dschuff

Subscribers: jfb, sbc100, jgravelle-google, sunfish, cfe-commits

Differential Revision: https://reviews.llvm.org/D44931

llvm-svn: 333703
2018-05-31 22:18:13 +00:00
Richard Smith 6ca999baf2 Revert r332839.
This is causing miscompiles and "definition with same mangled name as another
definition" errors.

llvm-svn: 333482
2018-05-30 00:45:10 +00:00
Akira Hatanaka 1da9dbbc25 [CodeGen][Darwin] Set the calling-convention of thread-local variable
initialization functions to 'cxx_fast_tlscc'.

This fixes a bug where instructions calling initialization functions for
thread-local static members of c++ template classes were using calling
convention 'cxx_fast_tlscc' while the called functions weren't annotated
with the calling convention.

rdar://problem/40447463

Differential Revision: https://reviews.llvm.org/D47354

llvm-svn: 333447
2018-05-29 18:28:49 +00:00
Richard Smith bbb2655de0 Revert r332028; see PR37545 for details.
llvm-svn: 332879
2018-05-21 20:10:54 +00:00
Pavel Labath b3b0255df9 [CodeGen] Disable aggressive structor optimizations at -O0, take 2
The first version of the patch (r332228) was flawed because it was
putting structors into C5/D5 comdats very eagerly. This is correct only
if we can ensure the comdat contains all required versions of the
structor (which wasn't the case). This version uses a more nuanced
approach:
- for local structor symbols we use an alias because we don't have to
  worry about comdats or other compilation units.
- linkonce symbols are emitted separately, as we cannot guarantee we
  will have all symbols we need to form a comdat (they are emitted
  lazily, only when referenced).
- available_externally symbols are also emitted separately, as the code
  seemed to be worried about emitting an alias in this case.
- other linkage types are not affected by the optimization level. They
  either get put into a comdat (weak) or get aliased (external).

Reviewers: rjmccall, aprantl

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D46685

llvm-svn: 332839
2018-05-21 11:47:45 +00:00
Reid Kleckner 138ab4947c Fix a mangling failure on clang-cl C++17
MethodVFTableLocations in MigrosoftVTableContext contains canonicalized
decl. But, it's sometimes asked to lookup for non-canonicalized decl,
and that causes assertion failure, and compilation failure.

Fixes PR37481.

Patch by Taiju Tsuiki!

Differential Revision: https://reviews.llvm.org/D46929

llvm-svn: 332639
2018-05-17 18:12:18 +00:00
Pavel Labath c370f26251 Revert "[CodeGen] Disable aggressive structor optimizations at -O0"
It breaks the sanitizer build
<http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/23739>

This reverts commit r332228.

llvm-svn: 332232
2018-05-14 11:35:44 +00:00
Pavel Labath f639eb0553 [CodeGen] Disable aggressive structor optimizations at -O0
Summary:
Removing the full structor and replacing all usages with the base one
can degrade debug quality as it will leave the debugger unable to locate
the full object structor. This is apparent when evaluating an expression
in the debugger which requires constructing an object of class which has
had this optimization applied to it.  When compiling the expression, we
pretend that the class and its methods have been defined in another
compilation unit, so the expression compiler assumes the structor
definition must be available. This didn't use to be the case for
structors with internal linkage. Less aggressive optimizations like
emitting the full structor as an alias remain in place, as they do not
cause the structor symbol to disappear completely.

This improves debug quality on non-darwin platforms (darwin does not
have -mconstructor-aliases on by default, so it is spared these
problems) and enable us to remove some workarounds from LLDB which attempt to
mitigate this issue.

Reviewers: rjmccall, aprantl

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D46685

llvm-svn: 332228
2018-05-14 11:02:23 +00:00
Eric Fiselier 85ba3321c6 [Itanium] Emit type info names with external linkage.
Summary:
The Itanium ABI requires that the type info for pointer-to-incomplete types to have internal linkage, so that it doesn't interfere with the type info once completed.  Currently it also marks the type info name as internal as well. However, this causes a bug with the STL implementations, which use the type info name pointer to perform ordering and hashing of type infos.
For example:

```
// header.h
struct T;
extern std::type_info const& Info;

// tu_one.cpp
#include "header.h"
std::type_info const& Info = typeid(T*);

// tu_two.cpp
#include "header.h"
struct T {};
int main() {
  auto &TI1 = Info;
  auto &TI2 = typeid(T*);
  assert(TI1 == TI2); // Fails
  assert(TI1.hash_code() == TI2.hash_code()); // Fails
}
```

This patch fixes the STL bug by emitting the type info name as linkonce_odr when the type-info is for a pointer-to-incomplete type.

Note that libc++ could fix this without a compiler change, but the quality of fix would be poor. The library would either have to:

(A) Always perform strcmp/string hashes.
(B) Determine if we have a pointer-to-incomplete type, and only do strcmp then. This would require an ABI break for libc++.


Reviewers: rsmith, rjmccall, majnemer, vsapsai

Reviewed By: rjmccall

Subscribers: smeenai, cfe-commits

Differential Revision: https://reviews.llvm.org/D46665

llvm-svn: 332028
2018-05-10 19:51:56 +00:00
Eric Fiselier 864ef70eb0 Revert "[Itanium] Emit type info names with external linkage."
This reverts commit r331957. It seems to be causing failures
on ppc64le-linux.

llvm-svn: 331963
2018-05-10 08:10:57 +00:00
Eric Fiselier ae56a957af [Itanium] Emit type info names with external linkage.
Summary:
The Itanium ABI requires that the type info for pointer-to-incomplete types to have internal linkage, so that it doesn't interfere with the type info once completed.  Currently it also marks the type info name as internal as well. However, this causes a bug with the STL implementations, which use the type info name pointer to perform ordering and hashing of type infos.
For example:

```
// header.h
struct T;
extern std::type_info const& Info;

// tu_one.cpp
#include "header.h"
std::type_info const& Info = typeid(T*);

// tu_two.cpp
#include "header.h"
struct T {};
int main() {
  auto &TI1 = Info;
  auto &TI2 = typeid(T*);
  assert(TI1 == TI2); // Fails
  assert(TI1.hash_code() == TI2.hash_code()); // Fails
}
```

This patch fixes the STL bug by emitting the type info name as linkonce_odr when the type-info is for a pointer-to-incomplete type.

Note that libc++ could fix this without a compiler change, but the quality of fix would be poor. The library would either have to:

(A) Always perform strcmp/string hashes.
(B) Determine if we have a pointer-to-incomplete type, and only do strcmp then. This would require an ABI break for libc++.


Reviewers: rsmith, rjmccall, majnemer, vsapsai

Reviewed By: rjmccall

Subscribers: smeenai, cfe-commits

Differential Revision: https://reviews.llvm.org/D46665

llvm-svn: 331957
2018-05-10 05:25:15 +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
Akira Hatanaka 617e26152d Add a command line option 'fregister_global_dtors_with_atexit' to
register destructor functions annotated with __attribute__((destructor))
using __cxa_atexit or atexit.

Register destructor functions annotated with __attribute__((destructor))
calling __cxa_atexit in a synthesized constructor function instead of
emitting references to the functions in a special section.

The primary reason for adding this option is that we are planning to
deprecate the __mod_term_funcs section on Darwin in the future. This
feature is enabled by default only on Darwin. Users who do not want this
can use command line option 'fno_register_global_dtors_with_atexit' to
disable it.

rdar://problem/33887655

Differential Revision: https://reviews.llvm.org/D45578

llvm-svn: 330199
2018-04-17 18:41:52 +00:00
Alexander Kornienko 2a8c18d991 Fix typos in clang
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
2018-04-06 15:14:32 +00:00
Richard Smith e78fac5126 PR36992: do not store beyond the dsize of a class object unless we know
the tail padding is not reused.

We track on the AggValueSlot (and through a couple of other
initialization actions) whether we're dealing with an object that might
share its tail padding with some other object, so that we can avoid
emitting stores into the tail padding if that's the case. We still
widen stores into tail padding when we can do so.

Differential Revision: https://reviews.llvm.org/D45306

llvm-svn: 329342
2018-04-05 20:52:58 +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
Rafael Espindola fe9a55a3f1 Bring r328238 back with a fix.
The issues was that we were setting hidden visibility if, when
processing a hidden class, we found out that we needed to emit a
reference to a vtable provided by the standard library.

Original message:

Set dso_local on vtables.

llvm-svn: 328288
2018-03-23 01:36:23 +00:00
Rafael Espindola f6688124b9 Revert "Set dso_local on vtables."
This reverts commit r328238.

Looks like it broke some buildbots.

llvm-svn: 328242
2018-03-22 21:14:16 +00:00
Rafael Espindola e006b8f486 Set dso_local on vtables.
llvm-svn: 328238
2018-03-22 20:33:01 +00:00
Yaxun Liu 5b330e8d61 Recommit r326946 after reducing CallArgList memory footprint
llvm-svn: 327634
2018-03-15 15:25:19 +00:00
Rafael Espindola 3f727a8f3a Set dso_local on external rtti GVs.
In this particular case it would be possible to just add an else with
CGM.setDSOLocal(GV), but it seems better to have as many callers as
possible just call setGVProperties so that we can centralize the logic
there.

This patch then makes setGVProperties able to handle null Decls.

llvm-svn: 327543
2018-03-14 18:14:46 +00:00
Richard Smith 007cb6df58 Revert r326946. It caused stack overflows by significantly increasing the size of a CallArgList.
llvm-svn: 327195
2018-03-10 01:47:22 +00:00
Rafael Espindola abdb322438 Set dso_local on tls init functions.
We copy the visibility, so copying the dso_local flag seems the
natural thing to do.

llvm-svn: 326961
2018-03-07 23:18:06 +00:00
Yaxun Liu 06dd81149f CodeGen: Fix address space of indirect function argument
The indirect function argument is in alloca address space in LLVM IR. However,
during Clang codegen for C++, the address space of indirect function argument
should match its address space in the source code, i.e., default addr space, even
for indirect argument. This is because destructor of the indirect argument may
be called in the caller function, and address of the indirect argument may be
taken, in either case the indirect function argument is expected to be in default
addr space, not the alloca address space.

Therefore, the indirect function argument should be mapped to the temp var
casted to default address space. The caller will cast it to alloca addr space
when passing it to the callee. In the callee, the argument is also casted to the
default address space and used.

CallArg is refactored to facilitate this fix.

Differential Revision: https://reviews.llvm.org/D34367

llvm-svn: 326946
2018-03-07 21:45:40 +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
Rafael Espindola b735004615 Start setting dllimport/dllexport in setGVProperties.
This is the next step in setting dso_local for COFF.

The patches changes setGVProperties to first set dllimport/dllexport
and changes a few cases that were setting dllimport/dllexport
manually. With this a few more GVs are marked dso_local.

llvm-svn: 326397
2018-03-01 00:35:47 +00:00
Rafael Espindola fa2fc906d2 Pass a GlobalDecl to setAliasAttributes. NFC.
This just makes a followup change easier to read.

llvm-svn: 326270
2018-02-28 00:06:01 +00:00
Rafael Espindola 922f2aa9b2 Bring r325915 back.
The tests that failed on a windows host have been fixed.

Original message:

Start setting dso_local for COFF.

With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325940
2018-02-23 19:30:48 +00:00
Rafael Espindola 43ce3a3a4d Revert "Start setting dso_local for COFF."
This reverts commit r325915.

It will take some time to fix the failures on a windows host.

llvm-svn: 325929
2018-02-23 18:09:29 +00:00
Rafael Espindola 004d240b6a Start setting dso_local for COFF.
With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325915
2018-02-23 15:32:32 +00:00
Rafael Espindola 3dd4981298 Simplify setting dso_local. NFC.
The value of dso_local can be computed from just IR properties and
global information (object file type, command line options, etc).

With this patch we no longer pass in the Decl. It was almost unused
and making it fully unused guarantees that dso_local is consistent
with the rest of the IR.

llvm-svn: 325846
2018-02-23 00:22:15 +00:00
Filipe Cabecinhas 4ba5817b8b ASan+operator new[]: Add an option for more thorough operator new[] cookie poisoning
Summary:
Right now clang is skipping array cookie poisoning for any operator
new[] which is not part of the set of replaceable global allocation
functions.

This commit adds a flag to tell clang to poison all operator new[]
cookies.

A previous review was poisoning all array cookies unconditionally, but
there is an edge case which would stop working under ASan (a custom
operator new[] saves whatever pointer it returned, and then accesses
it).

This newer revision adds a command line argument to toggle this feature.

Original revision: https://reviews.llvm.org/D41301
Compiler-rt test revision with an explanation of the edge case: https://reviews.llvm.org/D41664

Reviewers: rjmccall, kcc, rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D43013

llvm-svn: 324884
2018-02-12 11:49:02 +00:00
Rafael Espindola 699f5d6bbc Recommit r324107 again.
The difference from the previous try is that we no longer directly
access function declarations from position independent executables. It
should work, but currently doesn't with some linkers.

It now includes a fix to not mark available_externally definitions as
dso_local.

Original message:

Start setting dso_local in clang.

This starts adding dso_local to clang.

The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.

This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.

llvm-svn: 324535
2018-02-07 22:15:33 +00:00
Rafael Espindola 880c3b24c5 Revert "Recommit r324107."
This reverts commit r324500.

The bots found two failures:

    ThreadSanitizer-x86_64 :: Linux/pie_no_aslr.cc
    ThreadSanitizer-x86_64 :: pie_test.cc

when using gold. The issue is a limitation in gold when building pie
binaries. I will investigate how to work around it.

llvm-svn: 324505
2018-02-07 19:44:15 +00:00
Rafael Espindola fa9874c33b Recommit r324107.
It now includes a fix to not mark available_externally definitions as
dso_local.

Original message:

Start setting dso_local in clang.

This starts adding dso_local to clang.

The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.

This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.

llvm-svn: 324500
2018-02-07 19:16:49 +00:00
Rafael Espindola deb10becf3 Don't pass ForDefinition_t in places it is redundant.
I found this while looking at the ppc failures caused by the dso_local
change.

The issue was that the patch would produce the wrong answer for
available_externally. Having ForDefinition_t available in places where
the code can just check the linkage is a bit of a foot gun.

This patch removes the ForDefiniton_t argument in places where the
linkage is already know.

llvm-svn: 324499
2018-02-07 19:04:41 +00:00
John McCall 9831b843d2 Pass around function pointers as CGCallees, not bare llvm::Value*s.
The intention here is to make it easy to write frontend-assisted CFI
systems by propagating extra information in the CGCallee.

llvm-svn: 324377
2018-02-06 18:52:44 +00:00
Peter Collingbourne ea21100272 IRGen: Move vtable load after argument evaluation.
This change reduces the live range of the loaded function pointer,
resulting in a slight code size decrease (~10KB in clang), and also
improves the security of CFI for virtual calls by making it less
likely that the function pointer will be spilled, and ensuring that
it is not spilled across a function call boundary.

Fixes PR35353.

Differential Revision: https://reviews.llvm.org/D42725

llvm-svn: 324286
2018-02-05 23:09:13 +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
Rafael Espindola 9f34b7b93b Revert "Start setting dso_local in clang."
This reverts commit r324107.

I will have to test it on OS X.

llvm-svn: 324108
2018-02-02 17:29:22 +00:00
Rafael Espindola 7e34a308ff Start setting dso_local in clang.
This starts adding dso_local to clang.

The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.

This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.

llvm-svn: 324107
2018-02-02 17:17:39 +00:00
Martin Storsjo 3b528944ef [MinGW] Emit typeinfo locally for dllimported classes without key functions
This fixes building Qt as shared libraries with clang in MinGW
mode; previously subclasses of the QObjectData class (in other
DLLs than the base DLL) failed to find the typeinfo symbols
(that neither were emitted in the base DLL nor in the DLL
containing the subclass).

If the virtual destructor in the newly added testcase wouldn't
be pure (or if there'd be another non-pure virtual method),
it'd be a key function and things would work out even before this
change. Make sure to locally emit the typeinfo for these classes
as well.

This matches what GCC does in this specific testcase.

This fixes the root issue that spawned PR35146. (The difference
to GCC that is initially described in that bug still is present
though.)

Differential Revision: https://reviews.llvm.org/D42641

llvm-svn: 324059
2018-02-02 06:22:35 +00:00
Ivan A. Kosarev 1860b520a2 [CodeGen] Decorate aggregate accesses with TBAA tags
Differential Revision: https://reviews.llvm.org/D41539

llvm-svn: 323421
2018-01-25 14:21:55 +00:00
Stephan Bergmann 8c85bca5a5 No -fsanitize=function warning when calling noexcept function through non-noexcept pointer in C++17
As discussed in the mail thread <https://groups.google.com/a/isocpp.org/forum/
#!topic/std-discussion/T64_dW3WKUk> "Calling noexcept function throug non-
noexcept pointer is undefined behavior?", such a call should not be UB.
However, Clang currently warns about it.

This change removes exception specifications from the function types recorded
for -fsanitize=function, both in the functions themselves and at the call sites.
That means that calling a non-noexcept function through a noexcept pointer will
also not be flagged as UB.  In the review of this change, that was deemed
acceptable, at least for now.  (See the "TODO" in compiler-rt
test/ubsan/TestCases/TypeCheck/Function/function.cpp.)

To remove exception specifications from types, the existing internal
ASTContext::getFunctionTypeWithExceptionSpec was made public, and some places
otherwise unrelated to this change have been adapted to call it, too.

This is the cfe part of a patch covering both cfe and compiler-rt.

Differential Revision: https://reviews.llvm.org/D40720

llvm-svn: 321859
2018-01-05 07:57:12 +00:00