26 Commits

Author SHA1 Message Date
Arthur Eubanks
af0dbaaa38 Revert "Following up on PR48517, fix handling of template arguments that refer"
This reverts commit 8c1f2d15b826591cdf6bd6b468b8a7d23377b29e.

This is part of 5 commits being reverted due to https://crbug.com/1161059. See bug for repro.
2020-12-22 10:18:08 -08:00
Richard Smith
8c1f2d15b8 Following up on PR48517, fix handling of template arguments that refer
to dependent declarations.

Treat an id-expression that names a local variable in a templated
function as being instantiation-dependent.

This addresses a language defect whereby a reference to a dependent
declaration can be formed without any construct being value-dependent.
Fixing that through value-dependence turns out to be problematic, so
instead this patch takes the approach (proposed on the core reflector)
of allowing the use of pointers or references to (but not values of)
dependent declarations inside value-dependent expressions, and instead
treating template arguments as dependent if they evaluate to a constant
involving such dependent declarations.

This ends up affecting a bunch of OpenMP tests, due to OpenMP
imprecisely handling instantiation-dependent constructs, bailing out
early instead of processing dependent constructs to the extent possible
when handling the template.
2020-12-17 23:54:37 -08:00
Richard Smith
7e7f38f853 DR1413 and part of P1815R2: Minor improvements to Clang's determination
of type- and value-dependency.

A static data member initialized to a constant inside a class template
is no longer considered value-dependent, per DR1413. A const but not
constexpr variable of literal type (other than integer or enumeration)
is no longer considered value-dependent, per P1815R2.
2020-12-15 14:53:26 -08:00
Richard Smith
6b760a50f5 DR2100: &expr is value-dependent if expr constant-evaluates to a
dependent declaration.
2020-12-15 14:53:26 -08:00
Richard Smith
d1751d14a6 PR47175: Ensure type-dependent function-style casts have dependent
types.

Previously, a type-dependent cast to a deduced class template
specialization type would end up with a non-dependent class template
specialization type, leading to confusion downstream.
2020-10-08 17:00:22 -07:00
Haojian Wu
3423d5c9da [AST][RecoveryExpr] Popagate the error-bit from a VarDecl's initializer to DeclRefExpr.
The error-bit was missing, if a DeclRefExpr (which refers to a VarDecl
with a contains-errors initializer).

It could cause different violations in clang -- the DeclRefExpr is value-dependent,
but not contains-errors, `ABC<DeclRefExpr>` could produce a non-error
and non-dependent type in non-template context, which will lead to
crashes in constexpr evaluation.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D86048
2020-10-05 10:35:29 +02:00
Haojian Wu
f8f1e5fb39 [AST] Fix dependence-bits for CXXDefaultInitExpr.
Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D87382
2020-09-21 08:47:01 +02:00
Haojian Wu
566b49884d [clang] Set the error-bit for ill-formed semantic InitListExpr.
When a semantic checking fails on a syntactic InitListExpr, we will
get an ill-formed semantic InitListExpr (e.g. some inits are nullptr),
using this semantic InitListExpr in clang (without setting the err-bits) is crashy.

Differential Revision: https://reviews.llvm.org/D84140
2020-07-21 09:39:44 +02:00
Haojian Wu
6ac9e589f8 [clang][RecoveryExpr] Clarify the dependence-bits documentation.
The expr dependent-bits described that the expression somehow
depends on a template paramter.

With RecoveryExpr, we have generalized it to "the expression depends on
a template parameter, or an error".  This patch updates/cleanups all related
comments of dependence-bits.

Differential Revision: https://reviews.llvm.org/D83213
2020-07-13 11:32:32 +02:00
Haojian Wu
28ccd09d70 [AST][RecoveryExpr] Populate the dependence bits from CompoundStmt result expr to StmtExpr.
Summary:
We lost errorBit for StmtExpr if a recoveryExpr is the result
expr of a CompoundStmt, which will lead to crashes.

```
// `-StmtExpr
//   `-CompoundStmt
//     `-RecoveryExp
({ invalid(); });
```

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81154
2020-06-08 15:31:08 +02:00
Florian Hahn
8f3f88d2f5 [Matrix] Implement matrix index expressions ([][]).
This patch implements matrix index expressions
(matrix[RowIdx][ColumnIdx]).

It does so by introducing a new MatrixSubscriptExpr(Base, RowIdx, ColumnIdx).
MatrixSubscriptExprs are built in 2 steps in ActOnMatrixSubscriptExpr. First,
if the base of a subscript is of matrix type, we create a incomplete
MatrixSubscriptExpr(base, idx, nullptr). Second, if the base is an incomplete
MatrixSubscriptExpr, we create a complete
MatrixSubscriptExpr(base->getBase(), base->getRowIdx(), idx)

Similar to vector elements, it is not possible to take the address of
a MatrixSubscriptExpr.
For CodeGen, a new MatrixElt type is added to LValue, which is very
similar to VectorElt. The only difference is that we may need to cast
the type of the base from an array to a vector type when accessing it.

Reviewers: rjmccall, anemet, Bigcheese, rsmith, martong

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D76791
2020-06-01 20:08:49 +01:00
Haojian Wu
8222107aa9 [AST] Preserve the type in RecoveryExprs for broken function calls.
RecoveryExprs are modeled as dependent type to prevent bogus diagnostics
and crashes in clang.

This patch allows to preseve the type for broken calls when the
RecoveryEprs have a known type, e.g. a broken non-overloaded call, a
overloaded call when the all candidates have the same return type, so
that more features (code completion still work on "take2args(x).^") still
work.

However, adding the type is risky, which may result in more clang code being
affected leading to new crashes and hurt diagnostic, and it requires large
effort to minimize the affect (update all sites in clang to handle errorDepend
case), so we add a new flag (off by default) to allow us to develop/test
them incrementally.

This patch also has some trivial fixes to suppress diagnostics (to prevent regressions).

Tested:

all existing tests are passed (when both "-frecovery-ast", "-frecovery-ast-type" flags are flipped on);

Reviewed By: sammccall

Subscribers: rsmith, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79160
2020-05-11 08:46:18 +02:00
Haojian Wu
17198dfaff [AST] Fix recovery-expr crash on invalid aligned attr.
Summary:
crash stack:

```
lang: tools/clang/include/clang/AST/AttrImpl.inc:1490: unsigned int clang::AlignedAttr::getAlignment(clang::ASTContext &) const: Assertion `!isAlignmentDependent()' failed.
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: ./bin/clang -cc1 -std=c++1y -ast-dump -frecovery-ast -fcxx-exceptions /tmp/t4.cpp
1.      /tmp/t4.cpp:3:31: current parser token ';'
 #0 0x0000000002530cff llvm::sys::PrintStackTrace(llvm::raw_ostream&) llvm-project/llvm/lib/Support/Unix/Signals.inc:564:13
 #1 0x000000000252ee30 llvm::sys::RunSignalHandlers() llvm-project/llvm/lib/Support/Signals.cpp:69:18
 #2 0x000000000253126c SignalHandler(int) llvm-project/llvm/lib/Support/Unix/Signals.inc:396:3
 #3 0x00007f86964d0520 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x13520)
 #4 0x00007f8695f9ff61 raise /build/glibc-oCLvUT/glibc-2.29/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
 #5 0x00007f8695f8b535 abort /build/glibc-oCLvUT/glibc-2.29/stdlib/abort.c:81:7
 #6 0x00007f8695f8b40f _nl_load_domain /build/glibc-oCLvUT/glibc-2.29/intl/loadmsgcat.c:1177:9
 #7 0x00007f8695f98b92 (/lib/x86_64-linux-gnu/libc.so.6+0x32b92)
 #8 0x0000000004503d9f llvm::APInt::getZExtValue() const llvm-project/llvm/include/llvm/ADT/APInt.h:1623:5
 #9 0x0000000004503d9f clang::AlignedAttr::getAlignment(clang::ASTContext&) const llvm-project/build/tools/clang/include/clang/AST/AttrImpl.inc:1492:0
```

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78085
2020-04-15 16:15:20 +02:00
Alexey Bataev
13a1504ffb [OPENMP50]Add initial support for OpenMP 5.0 iterator.
Added basic parsing/semantic analysis/(de)serialization support for
iterator expression introduced in OpenMP 5.0.
2020-04-02 08:28:15 -04:00
Alexey Bataev
c028472fa1 Revert "[OPENMP50]Add initial support for OpenMP 5.0 iterator."
This reverts commit f08df464ae89972a777c0a7e299a2c153a9829d8 to fix the
bug with serialization support for iterator expression.
2020-04-01 14:54:45 -04:00
Alexey Bataev
f08df464ae [OPENMP50]Add initial support for OpenMP 5.0 iterator.
Added basic parsing/semantic analysis/(de)serialization support for
iterator expression introduced in OpenMP 5.0.
2020-04-01 12:53:55 -04:00
Alexey Bataev
7ac9efb0c3 [OPENMP50]Add basic support for array-shaping operation.
Summary:
Added basic representation and parsing/sema handling of array-shaping
operations. Array shaping expression is an expression of form ([s0]..[sn])base,
where s0, ..., sn must be a positive integer, base - a pointer. This
expression is a kind of cast operation that converts pointer expression
into an array-like kind of expression.

Reviewers: rjmccall, rsmith, jdoerfert

Subscribers: guansong, arphaman, cfe-commits, caomhin, kkwli0

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74144
2020-03-30 09:18:24 -04:00
Sam McCall
d68c09ac87 [AST] Add a Dependence bitmask to use for calculations with multiple node types.
Summary:
This makes it easier/safer to add bits (error) to other node types without
worrying about bit layout all the time.

For now, just use to implement the ad-hoc conversion functions.
Next: remove these functions and use this directly.

Reviewers: hokein

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76939
2020-03-28 00:15:50 +01:00
Sam McCall
018ad3b05e [AST] Fix typo on NoInitExpr dependence computation 2020-03-27 19:40:25 +01:00
Haojian Wu
733edf9750 [AST] Add RecoveryExpr to retain expressions on semantic errors
Normally clang avoids creating expressions when it encounters semantic
errors, even if the parser knows which expression to produce.

This works well for the compiler. However, this is not ideal for
source-level tools that have to deal with broken code, e.g. clangd is
not able to provide navigation features even for names that compiler
knows how to resolve.

The new RecoveryExpr aims to capture the minimal set of information
useful for the tools that need to deal with incorrect code:

source range of the expression being dropped,
subexpressions of the expression.
We aim to make constructing RecoveryExprs as simple as possible to
ensure writing code to avoid dropping expressions is easy.

Producing RecoveryExprs can result in new code paths being taken in the
frontend. In particular, clang can produce some new diagnostics now and
we aim to suppress bogus ones based on Expr::containsErrors.

We deliberately produce RecoveryExprs only in the parser for now to
minimize the code affected by this patch. Producing RecoveryExprs in
Sema potentially allows to preserve more information (e.g. type of an
expression), but also results in more code being affected. E.g.
SFINAE checks will have to take presence of RecoveryExprs into account.

Initial implementation only works in C++ mode, as it relies on compiler
postponing diagnostics on dependent expressions. C and ObjC often do not
do this, so they require more work to make sure we do not produce too
many bogus diagnostics on the new expressions.

See documentation of RecoveryExpr for more details.

original patch from Ilya
This change is based on https://reviews.llvm.org/D61722

Reviewers: sammccall, rsmith

Reviewed By: sammccall, rsmith

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69330
2020-03-24 09:20:37 +01:00
Sam McCall
b4f02d89e5 [AST] Make Expr::setDependence protected and remove add/removeDependence. NFC
Summary:
The expected pattern is for subclasses to initialize through
computeDependence, which needs only setDependence.
The few places that still use addDependence can be simulated with get+set.

Reviewers: hokein

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76392
2020-03-19 21:54:40 +01:00
Haojian Wu
4b0f1e12c2 [AST] Add a flag indicating if any subexpression had errors
The only subexpression that is considered an error now is TypoExpr, but
we plan to add expressions with errors to improve editor tooling on broken
code. We intend to use the same mechanism to guard against spurious
diagnostics on those as well.

See the follow-up revision for an actual usage of the flag.

Original patch from Ilya.

Reviewers: sammccall

Reviewed By: sammccall

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65591
2020-03-19 08:56:10 +01:00
Haojian Wu
d3d844212f Fix the buildbot error. 2020-03-17 09:49:43 +01:00
Haojian Wu
876bb86e26 [AST] Move dependence computations into a separate file
To group the code in one place, simplify it and make it easier to add
the containsErrors bit and find existing bugs.

Reviewers: sammccall

Reviewed By: sammccall

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73638
2020-03-17 09:22:31 +01:00
Haojian Wu
18c9766248 Revert "[AST] Move dependence computations into a separate file"
This reverts commit ddd20ed1586c55947e84620d674a60c118ec6905.
The patch was landed by accident.
2020-03-16 16:49:38 +01:00
Ilya Biryukov
ddd20ed158 [AST] Move dependence computations into a separate file
To group the code in one place, simplify it and make it easier to add
the containsErrors bit and find existing bugs.
2020-03-16 16:48:49 +01:00