10 Commits

Author SHA1 Message Date
Matheus Izvekov
d9308aa39b [clang] don't mark as Elidable CXXConstruct expressions used in NRVO
See PR51862.

The consumers of the Elidable flag in CXXConstructExpr assume that
an elidable construction just goes through a single copy/move construction,
so that the source object is immediately passed as an argument and is the same
type as the parameter itself.

With the implementation of P2266 and after some adjustments to the
implementation of P1825, we started (correctly, as per standard)
allowing more cases where the copy initialization goes through
user defined conversions.

With this patch we stop using this flag in NRVO contexts, to preserve code
that relies on that assumption.
This causes no known functional changes, we just stop firing some asserts
in a cople of included test cases.

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D109800
2021-09-21 21:41:20 +02:00
Matheus Izvekov
f2d5fce86e [clang] fixes named return of variables with dependent alignment
Named return of a variable with aligned attribute would
trip an assert in case alignment was dependent.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D105380
2021-07-07 02:54:55 +02:00
Adrian Kuegel
cbb09c5b2c Revert "[clang] fixes named return of variables with dependent alignment"
This reverts commit 21106388eb96c87b3f580c42a322c76a61605261.
It causes a segfault in certain cases.
2021-07-06 10:31:39 +02:00
Matheus Izvekov
21106388eb [clang] fixes named return of variables with dependent alignment
Named return of a variable with aligned attribute would
trip an assert in case alignment was dependent.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D105380
2021-07-06 02:30:44 +02:00
Matheus Izvekov
12c90e2e25 [clang] NRVO: Improvements and handling of more cases.
This expands NRVO propagation for more cases:

Parse analysis improvement:
* Lambdas and Blocks with dependent return type can have their variables
  marked as NRVO Candidates.

Variable instantiation improvements:
* Fixes crash when instantiating NRVO variables in Blocks.
* Functions, Lambdas, and Blocks which have auto return type have their
  variables' NRVO status propagated. For Blocks with non-auto return type,
  as a limitation, this propagation does not consider the actual return
  type.

This also implements exclusion of VarDecls which are references to
dependent types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D99696
2021-06-17 01:56:38 +02:00
Hans Wennborg
c60dd3b262 Revert "[clang] NRVO: Improvements and handling of more cases."
This change caused build errors related to move-only __block variables,
see discussion on https://reviews.llvm.org/D99696

> This expands NRVO propagation for more cases:
>
> Parse analysis improvement:
> * Lambdas and Blocks with dependent return type can have their variables
>   marked as NRVO Candidates.
>
> Variable instantiation improvements:
> * Fixes crash when instantiating NRVO variables in Blocks.
> * Functions, Lambdas, and Blocks which have auto return type have their
>   variables' NRVO status propagated. For Blocks with non-auto return type,
>   as a limitation, this propagation does not consider the actual return
>   type.
>
> This also implements exclusion of VarDecls which are references to
> dependent types.
>
> Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
>
> Reviewed By: Quuxplusone
>
> Differential Revision: https://reviews.llvm.org/D99696

This also reverts the follow-on change which was hard to tease apart
form the one above:

> "[clang] Implement P2266 Simpler implicit move"
>
> This Implements [[http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2266r1.html|P2266 Simpler implicit move]].
>
> Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
>
> Reviewed By: Quuxplusone
>
> Differential Revision: https://reviews.llvm.org/D99005

This reverts commits 1e50c3d785f4563873ab1ce86559f2a1285b5678 and
bf20631782183cd19e0bb7219e908c2bbb01a75f.
2021-06-14 16:46:58 +02:00
Matheus Izvekov
1e50c3d785 [clang] NRVO: Improvements and handling of more cases.
This expands NRVO propagation for more cases:

Parse analysis improvement:
* Lambdas and Blocks with dependent return type can have their variables
  marked as NRVO Candidates.

Variable instantiation improvements:
* Fixes crash when instantiating NRVO variables in Blocks.
* Functions, Lambdas, and Blocks which have auto return type have their
  variables' NRVO status propagated. For Blocks with non-auto return type,
  as a limitation, this propagation does not consider the actual return
  type.

This also implements exclusion of VarDecls which are references to
dependent types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D99696
2021-06-12 16:43:32 +02:00
Arthur Eubanks
85ca7e424f Revert "[clang] NRVO: Improvements and handling of more cases."
This reverts commit 667fbcdd0b2ee5e78f5ce9789b862e3bbca94644.

Causes crashes on a stage 2 build on Windows.
2021-06-10 20:37:01 -07:00
Matheus Izvekov
667fbcdd0b [clang] NRVO: Improvements and handling of more cases.
This expands NRVO propagation for more cases:

Parse analysis improvement:
* Lambdas and Blocks with dependent return type can have their variables
  marked as NRVO Candidates.

Variable instantiation improvements:
* Fixes crash when instantiating NRVO variables in Blocks.
* Functions, Lambdas, and Blocks which have auto return type have their
  variables' NRVO status propagated. For Blocks with non-auto return type,
  as a limitation, this propagation does not consider the actual return
  type.

This also implements exclusion of VarDecls which are references to
dependent types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D99696
2021-06-10 23:02:51 +02:00
Matheus Izvekov
1819222860 [clang] tests: cleanup, update and add some new ones
This reworks a small set of tests, as preparatory work for implementing
P2266.
* Run for more standard versions, including c++2b.
* Normalize file names and run commands.
* Adds some extra tests.

New Coroutine tests taken from Aaron Puchert's D68845.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: thakis

Differential Revision: https://reviews.llvm.org/D99225
2021-04-09 17:24:08 +02:00