Revert "[clang] Implement ElaboratedType sugaring for types written bare"

This reverts commit 7c51f02effdbd0d5e12bfd26f9c3b2ab5687c93f because it
stills breaks the LLDB tests. This was re-landed wi

Revert "[clang] Implement ElaboratedType sugaring for types written bare"

This reverts commit 7c51f02effdbd0d5e12bfd26f9c3b2ab5687c93f because it
stills breaks the LLDB tests. This was re-landed without addressing the
issue or even agreement on how to address the issue. More details and
discussion in https://reviews.llvm.org/D112374.

show more ...

[clang] Implement ElaboratedType sugaring for types written bare

Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which go

[clang] Implement ElaboratedType sugaring for types written bare

Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
a type is printed. The type printer will, by design and default,
print types as written. There are customization options there, but
not that many, and they mainly apply to how to print a type that we
somehow failed to track how it was written. This patch fixes a
problem where we failed to distinguish between a type
that was written without any elaborated-type qualifiers,
such as a 'struct'/'class' tags and name spacifiers such as 'std::',
and one that has been stripped of any 'metadata' that identifies such,
the so called canonical types.
Example:
```
namespace foo {
struct A {};
A a;
};
```
If one were to print the type of `foo::a`, prior to this patch, this
would result in `foo::A`. This is how the type printer would have,
by default, printed the canonical type of A as well.
As soon as you add any name qualifiers to A, the type printer would
suddenly start accurately printing the type as written. This patch
will make it print it accurately even when written without
qualifiers, so we will just print `A` for the initial example, as
the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
is harder to get right when there is sugar involved. For example,
if you want to match a type against being a pointer to some type A,
then you have to account for getting a type that is sugar for a
pointer to A, or being a pointer to sugar to A, or both! Usually
you would get the second part wrong, and this would work for a
very simple test where you don't use any name qualifiers, but
you would discover is broken when you do. The usual fix is to
either use the matcher which strips sugar, which is annoying
to use as for example if you match an N level pointer, you have
to put N+1 such matchers in there, beginning to end and between
all those levels. But in a lot of cases, if the property you want
to match is present in the canonical type, it's easier and faster
to just match on that... This goes with what is said in 1), if
you want to match against the name of a type, and you want
the name string to be something stable, perhaps matching on
the name of the canonical type is the better choice.

3) This patch could exposed a bug in how you get the source range of some
TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
which only looks at the given TypeLoc node. This patch introduces a new,
and more common TypeLoc node which contains no source locations on itself.
This is not an inovation here, and some other, more rare TypeLoc nodes could
also have this property, but if you use getLocalSourceRange on them, it's not
going to return any valid locations, because it doesn't have any. The right fix
here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
into the inner TypeLoc to get the source range if it doesn't find it on the
top level one. You can use getLocalSourceRange if you are really into
micro-optimizations and you have some outside knowledge that the TypeLocs you are
dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
have some type, you want to see if that type is some particular kind, you try a
`dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
Again, like 2), this would usually have been tested poorly with some simple tests with
no qualifications, and would have been broken had there been any other kind of type sugar,
be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <[email protected]>

Differential Revision: https://reviews.llvm.org/D112374

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Revert "[clang] Implement ElaboratedType sugaring for types written bare"

This reverts commit bdc6974f92304f4ed542241b9b89ba58ba6b20aa because it
breaks all the LLDB tests that import the std module

Revert "[clang] Implement ElaboratedType sugaring for types written bare"

This reverts commit bdc6974f92304f4ed542241b9b89ba58ba6b20aa because it
breaks all the LLDB tests that import the std module.

import-std-module/array.TestArrayFromStdModule.py
import-std-module/deque-basic.TestDequeFromStdModule.py
import-std-module/deque-dbg-info-content.TestDbgInfoContentDequeFromStdModule.py
import-std-module/forward_list.TestForwardListFromStdModule.py
import-std-module/forward_list-dbg-info-content.TestDbgInfoContentForwardListFromStdModule.py
import-std-module/list.TestListFromStdModule.py
import-std-module/list-dbg-info-content.TestDbgInfoContentListFromStdModule.py
import-std-module/queue.TestQueueFromStdModule.py
import-std-module/stack.TestStackFromStdModule.py
import-std-module/vector.TestVectorFromStdModule.py
import-std-module/vector-bool.TestVectorBoolFromStdModule.py
import-std-module/vector-dbg-info-content.TestDbgInfoContentVectorFromStdModule.py
import-std-module/vector-of-vectors.TestVectorOfVectorsFromStdModule.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45301/

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[clang] Implement ElaboratedType sugaring for types written bare

Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which go

[clang] Implement ElaboratedType sugaring for types written bare

Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

Signed-off-by: Matheus Izvekov <[email protected]>

Differential Revision: https://reviews.llvm.org/D112374

show more ...

[Concepts] Implement overload resolution for destructors (P0848)

This patch implements a necessary part of P0848, the overload resolution for destructors.
It is now possible to overload destructors

[Concepts] Implement overload resolution for destructors (P0848)

This patch implements a necessary part of P0848, the overload resolution for destructors.
It is now possible to overload destructors based on constraints, and the eligible destructor
will be selected at the end of the class.

The approach this patch takes is to perform the overload resolution in Sema::ActOnFields
and to mark the selected destructor using a new property in FunctionDeclBitfields.

CXXRecordDecl::getDestructor is then modified to use this property to return the correct
destructor.

This closes https://github.com/llvm/llvm-project/issues/45614.

Reviewed By: #clang-language-wg, erichkeane

Differential Revision: https://reviews.llvm.org/D126194

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[AST] injected-class-name is not a redecl, even in template specializations

Back in the mists of time, the CXXRecordDecl for the injected-class-name was
a redecl of the outer class itself.
This got

[AST] injected-class-name is not a redecl, even in template specializations

Back in the mists of time, the CXXRecordDecl for the injected-class-name was
a redecl of the outer class itself.
This got changed in 470c454a6176ef31474553e408c90f5ee630df89, but only for plain
classes: class template instantation was still detecting the injected-class-name
in the template body and marking its instantiation as a redecl.

This causes some subtle inconsistent behavior between the two, e.g.
hasDefinition() returns true for Foo<int>::Foo but false for Bar::Bar.
This is the root cause of PR51912.

Differential Revision: https://reviews.llvm.org/D112765

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[clang] NFC: remove carriage return from AST tests

Signed-off-by: Matheus Izvekov <[email protected]>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D112372

[clang] Rework how and when APValues are dumped

Currently APValues are dumped as a single string. This becomes quickly
completely unreadable since APValue is a tree-like structure. Even a simple
exa

[clang] Rework how and when APValues are dumped

Currently APValues are dumped as a single string. This becomes quickly
completely unreadable since APValue is a tree-like structure. Even a simple
example is not pretty:

struct S { int arr[4]; float f; };
constexpr S s = { .arr = {1,2}, .f = 3.1415f };
// Struct fields: Array: Int: 1, Int: 2, 2 x Int: 0, Float: 3.141500e+00

With this patch this becomes:

-Struct
|-field: Array size=4
| |-elements: Int 1, Int 2
| `-filler: 2 x Int 0
`-field: Float 3.141500e+00

Additionally APValues are currently only dumped as part of visiting a
ConstantExpr. This patch also dump the value of the initializer of constexpr
variable declarations:

constexpr int foo(int a, int b) { return a + b - 42; }
constexpr int a = 1, b = 2;
constexpr int c = foo(a, b) > 0 ? foo(a, b) : foo(b, a);
// VarDecl 0x62100008aec8 <col:3, col:57> col:17 c 'const int' constexpr cinit
// |-value: Int -39
// `-ConditionalOperator 0x62100008b4d0 <col:21, col:57> 'int'
// <snip>

Do the above by moving the dump functions to TextNodeDumper which already has
the machinery to display trees. The cases APValue::LValue, APValue::MemberPointer
and APValue::AddrLabelDiff are left as they were before (unimplemented).

We try to display multiple elements on the same line if they are considered to
be "simple". This is to avoid wasting large amounts of vertical space in an
example like:

constexpr int arr[8] = {0,1,2,3,4,5,6,7};
// VarDecl 0x62100008bb78 <col:3, col:42> col:17 arr 'int const[8]' constexpr cinit
// |-value: Array size=8
// | |-elements: Int 0, Int 1, Int 2, Int 3
// | `-elements: Int 4, Int 5, Int 6, Int 7

Differential Revision: https://reviews.llvm.org/D83183

Reviewed By: aaron.ballman

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AST dump: recurse into type template arguments when dumping.

Also, do not dump the desugared type for a TemplateSpecializationType
twice.

[clang][test][NFC] Also test for serialization in AST dump tests, part 2/n.

The outputs between the direct ast-dump test and the ast-dump test after
deserialization should match modulo a few differe

[clang][test][NFC] Also test for serialization in AST dump tests, part 2/n.

The outputs between the direct ast-dump test and the ast-dump test after
deserialization should match modulo a few differences.

For hand-written tests, strip the "<undeserialized declarations>"s and
the "imported"s with sed.

For tests generated with "make-ast-dump-check.sh", regenerate the
output.

Part 2/n.

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PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-condi

PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-conditions), we would
always invoke it, and could avoid going through overload resolution.
That turns out to not be correct in the presenve of ref-qualifiers (and
also won't be the case for copy-assignments with requires-clauses
either). Use the same logic for lazy declaration of copy-assignments
that we use for all other special member functions.

Previously committed as c57f8a3a20540fcf9fbf98c0a73f381ec32fce2a. This
now also includes an extension of LLDB's workaround for handling special
members without the help of Sema to cover copy assignments.

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Revert "PR46209: properly determine whether a copy assignment operator is"

This reverts commit c57f8a3a20540fcf9fbf98c0a73f381ec32fce2a.

PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-condi

PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-conditions), we would
always invoke it, and could avoid going through overload resolution.
That turns out to not be correct in the presenve of ref-qualifiers (and
also won't be the case for copy-assignments with requires-clauses
either). Use the same logic for lazy declaration of copy-assignments
that we use for all other special member functions.

show more ...

[clang] Make handling of unnamed template params similar to function params

Summary:
Clang uses the location identifier should be inserted for declarator
decls when a decl is unnamed. But for type t

[clang] Make handling of unnamed template params similar to function params

Summary:
Clang uses the location identifier should be inserted for declarator
decls when a decl is unnamed. But for type template and template template
paramaters it uses the location of "typename/class" keyword, which makes it hard
for tooling to insert/change parameter names.

This change tries to unify these two cases by making template parameter
parsing and sourcerange operations similar to function params/declarator decls.

Reviewers: ilya-biryukov

Subscribers: arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68143

llvm-svn: 373340

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[ASTDump] Make template specialization tests more exact

Reviewers: aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D57502

llvm-svn: 352804

Re-order content of template parameter dumps

Reviewers: aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D55393

llvm-svn: 348797

Add dump tests for inherited default template parameters

llvm-svn: 348408

Move AST tests into their own test directory; NFC.

This moves everything primarily testing the functionality of -ast-dump and -ast-print into their own directory, rather than leaving the tests sprea

Move AST tests into their own test directory; NFC.

This moves everything primarily testing the functionality of -ast-dump and -ast-print into their own directory, rather than leaving the tests spread around the testing directory.

llvm-svn: 348017

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