Commit Graph

19 Commits

Author SHA1 Message Date
Aaron Ballman 9fcca8b470 Fix consteval crash when transforming 'this' expressions
When reaching the end of a function body, we need to ensure that the
ExitFunctionBodyRAII object is destroyed before we pop the declaration context
for the function. Exiting the function body causes us to handle immediate
invocations, which involves template transformations that need to know the
correct type for this.

This addresses PR48235.
2021-10-27 11:25:07 -04:00
Aaron Ballman b9941de0bf Fix a rejects-valid with consteval on overloaded operators
It seems that Clang 11 regressed functionality that was working in
Clang 10 regarding calling a few overloaded operators in an immediate
context. Specifically, we were not checking for immediate invocations
of array subscripting and the arrow operators, but we properly handle
the other overloaded operators.

This fixes the two problematic operators and adds some test coverage to
show they're equivalent to calling the operator directly.

This addresses PR50779.
2021-10-14 14:47:29 -04:00
Corentin Jabot 131b4620ee Implement P1937 consteval in unevaluated contexts
In an unevaluated contexts, consteval functions should not be
immediately evaluated.
2021-08-06 10:29:28 -04:00
Richard Smith f7f2e4261a PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-14 17:43:51 -07:00
Richard Smith 69f7c006ff Revert "PR47805: Use a single object for a function parameter in the caller and"
Breaks a clangd unit test.

This reverts commit 8f8b9f2cca.
2020-10-13 19:32:03 -07:00
Richard Smith 8f8b9f2cca PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-13 18:50:46 -07:00
Richard Smith ab870f3030 Revert "PR47805: Use a single object for a function parameter in the caller and"
The buildbots are displeased.

This reverts commit 8d03a972ce.
2020-10-13 15:59:00 -07:00
Richard Smith 8d03a972ce PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-13 15:45:04 -07:00
Richard Smith 5a5f5350e1 [c++20] Fix handling of operator rewrites naming consteval operator<=>. 2020-06-29 19:02:47 -07:00
Tyker 51e4aa87e0 attempt to fix failing buildbots after 3bab88b7ba
Prevent IR-gen from emitting consteval declarations

Summary: with this patch instead of emitting calls to consteval function. the IR-gen will emit a store of the already computed result.
2020-06-15 12:58:37 +02:00
Kirill Bobyrev 550c4562d1 Revert "Prevent IR-gen from emitting consteval declarations"
This reverts commit 3bab88b7ba.

This patch causes test failures:
http://lab.llvm.org:8011/builders/clang-cmake-armv7-quick/builds/17260
2020-06-15 12:14:15 +02:00
Tyker 3bab88b7ba Prevent IR-gen from emitting consteval declarations
Summary: with this patch instead of emitting calls to consteval function. the IR-gen will emit a store of the already computed result.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76420
2020-06-15 10:47:14 +02:00
Tyker 180581cfcf [clang] Add support for consteval constructors
Summary:
Changes:
 - handle immediate invocations for constructors.
 - add tests

after this patch i believe the implementation of consteval is nearly standard compliant, but IR-gen still needs to be taught not to emit consteval declarations.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: wchilders

Differential Revision: https://reviews.llvm.org/D74007
2020-03-20 11:33:54 +01:00
Richard Smith 9975dc38bf Defer checking for mismatches between the deletedness of and overriding
function and an overridden function until we know whether the overriding
function is deleted.

We previously did these checks when we first built the declaration,
which was too soon in some cases. We now defer all these checks to the
end of the class.

Also add missing check that a consteval function cannot override a
non-consteval function and vice versa.
2020-03-12 13:07:22 -07:00
Tyker ca50f09db9 [clang] fix error detection in consteval calls
Summary:
code like:
```
consteval int f() {
  int *A = new int(0);
  return *A;
}

int i1 = f();
```
currently doesn't generate any error.

Reviewers: rsmith

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D74418
2020-02-26 21:09:31 +01:00
Tyker f5d1a9f1cf Try to fix windows build bot after 008e7bf923 2020-02-04 21:20:16 +01:00
Tyker 008e7bf923 [C++20] Add consteval-specific semantic for functions
Summary:
Changes:
 - Calls to consteval function are now evaluated in constant context but IR is still generated for them.
 - Add diagnostic for taking address of a consteval function in non-constexpr context.
 - Add diagnostic for address of consteval function accessible at runtime.
 - Add tests

Reviewers: rsmith, aaron.ballman

Reviewed By: rsmith

Subscribers: mgrang, riccibruno, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63960
2020-02-04 20:38:32 +01:00
Richard Smith 457226e02a For P0784R7: add support for constexpr destructors, and call them as
appropriate during constant evaluation.

Note that the evaluator is sometimes invoked on incomplete expressions.
In such cases, if an object is constructed but we never reach the point
where it would be destroyed (and it has non-trivial destruction), we
treat the expression as having an unmodeled side-effect.

llvm-svn: 372538
2019-09-23 03:48:44 +00:00
Gauthier Harnisch 796ed03b84 [C++20] add Basic consteval specifier
Summary:
this revision adds Lexing, Parsing and Basic Semantic for the consteval specifier as specified by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1073r3.html

with this patch, the consteval specifier is treated as constexpr but can only be applied to function declaration.

Changes:
 - add the consteval keyword.
 - add parsing of consteval specifier for normal declarations and lambdas expressions.
 - add the whether a declaration is constexpr is now represented by and enum everywhere except for variable because they can't be consteval.
 - adapt diagnostic about constexpr to print constexpr or consteval depending on the case.
 - add tests for basic semantic.

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: eraman, efriedma, rnkovacs, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61790

llvm-svn: 363362
2019-06-14 08:56:20 +00:00