Commit Graph

6 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 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
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