Reapply "[clang] Avoid re-evaluating field bitwidth" (#122289)

Revert "[clang] Avoid re-evaluating field bitwidth (#117732)"

This reverts commit 81fc3add1e627c23b7270fe2739cdacc09063e54.

This breaks some LLDB tests, e.g.
SymbolFile/DWARF/x86/no_unique_address-

Revert "[clang] Avoid re-evaluating field bitwidth (#117732)"

This reverts commit 81fc3add1e627c23b7270fe2739cdacc09063e54.

This breaks some LLDB tests, e.g.
SymbolFile/DWARF/x86/no_unique_address-with-bitfields.cpp:

lldb: ../llvm-project/clang/lib/AST/Decl.cpp:4604: unsigned int clang::FieldDecl::getBitWidthValue() const: Assertion `isa<ConstantExpr>(getBitWidth())' failed.

show more ...

[clang] Avoid re-evaluating field bitwidth (#117732)

Save the bitwidth value as a `ConstantExpr` with the value set. Remove
the `ASTContext` parameter from `getBitWidthValue()`, so the latter
simply

[clang] Avoid re-evaluating field bitwidth (#117732)

Save the bitwidth value as a `ConstantExpr` with the value set. Remove
the `ASTContext` parameter from `getBitWidthValue()`, so the latter
simply returns the value from the `ConstantExpr` instead of
constant-evaluating the bitwidth expression every time it is called.

show more ...

[clang-tidy][NFC] Fix cppcoreguidelines-init-variables findings

Fix issues found by clang-tidy in clang-tidy source directory.

[clang-tidy][NFC] Use C++17 nested namespaces in the clang-tidy folder

Fix applied by running:

run-clang-tidy.py -checks=-*,modernize-concat-nested-namespaces

Differential Revision: https://review

[clang-tidy][NFC] Use C++17 nested namespaces in the clang-tidy folder

Fix applied by running:

run-clang-tidy.py -checks=-*,modernize-concat-nested-namespaces

Differential Revision: https://reviews.llvm.org/D141770

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 expose 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 <mizvekov@gmail.com>

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

show more ...

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 <mizvekov@gmail.com>

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

show more ...

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/

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.

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

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

show more ...

[clang-tidy] Applied clang-tidy fixes. NFC

Applied fixes enabled by the LLVM's .clang-tidy configs. Reverted files where
fixes introduced compile errors:
clang-tools-extra/clang-tidy/hicpp/NoAssem

[clang-tidy] Applied clang-tidy fixes. NFC

Applied fixes enabled by the LLVM's .clang-tidy configs. Reverted files where
fixes introduced compile errors:
clang-tools-extra/clang-tidy/hicpp/NoAssemblerCheck.cpp
clang-tools-extra/clang-tidy/misc/ThrowByValueCatchByReferenceCheck.cpp

$ clang-tools-extra/clang-tidy/tool/run-clang-tidy.py -fix clang-tools-extra/clang-tidy/
Enabled checks:
llvm-else-after-return
llvm-header-guard
llvm-include-order
llvm-namespace-comment
llvm-prefer-isa-or-dyn-cast-in-conditionals
llvm-prefer-register-over-unsigned
llvm-qualified-auto
llvm-twine-local
misc-definitions-in-headers
misc-misplaced-const
misc-new-delete-overloads
misc-no-recursion
misc-non-copyable-objects
misc-redundant-expression
misc-static-assert
misc-throw-by-value-catch-by-reference
misc-unconventional-assign-operator
misc-uniqueptr-reset-release
misc-unused-alias-decls
misc-unused-using-decls
readability-identifier-naming

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D95614

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[clang-tools-extra] NFC: Fix trivial typo in documents and comments

Differential Revision: https://reviews.llvm.org/D77458

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the ne

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

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A bit of AST matcher cleanup, NFC.

Removed the uses of the allOf() matcher inside node matchers that are implicit
allOf(). Replaced uses of allOf() with the explicit node matcher where it makes
matc

A bit of AST matcher cleanup, NFC.

Removed the uses of the allOf() matcher inside node matchers that are implicit
allOf(). Replaced uses of allOf() with the explicit node matcher where it makes
matchers more readable. Replace anyOf(hasName(), hasName(), ...) with the more
efficient and readable hasAnyName().

llvm-svn: 347520

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Port getLocStart -> getBeginLoc

Reviewers: javed.absar

Subscribers: nemanjai, kbarton, ilya-biryukov, ioeric, jkorous, arphaman, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D5

Port getLocStart -> getBeginLoc

Reviewers: javed.absar

Subscribers: nemanjai, kbarton, ilya-biryukov, ioeric, jkorous, arphaman, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D50354

llvm-svn: 339400

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[Fix] fix type deduction on ARM and MSVC

llvm-svn: 328108

[clang-tidy] Resubmit hicpp-multiway-paths-covered without breaking test

The original check did break the green buildbot in the sanitizer build.
It took a while to redroduce and understand the issue

[clang-tidy] Resubmit hicpp-multiway-paths-covered without breaking test

The original check did break the green buildbot in the sanitizer build.
It took a while to redroduce and understand the issue.

There occured a stackoverflow while parsing the AST. The testcase with
256 case labels was the problem because each case label added another
stackframe. It seemed that the issue occured only in 'RelWithDebInfo' builds
and not in normal sanitizer builds.

To simplify the matchers the recognition for the different kinds of switch
statements has been moved into a seperate function and will not be done with
ASTMatchers. This is an attempt to reduce recursion and stacksize as well.

The new check removed this big testcase. Covering all possible values is still
implemented for bitfields and works there. The same logic on integer types
will lead to the issue.

Running it over LLVM gives the following results:


Differential: https://reviews.llvm.org/D40737
llvm-svn: 328107

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[clang-tidy] Add new hicpp-multiway-paths-covered check for missing branches

Summary:
This check searches for missing `else` branches in `if-else if`-chains and
missing `default` labels in `switch`

[clang-tidy] Add new hicpp-multiway-paths-covered check for missing branches

Summary:
This check searches for missing `else` branches in `if-else if`-chains and
missing `default` labels in `switch` statements, that use integers as condition.

It is very similar to -Wswitch, but concentrates on integers only, since enums are
already covered.

The option to warn for missing `else` branches is deactivated by default, since it is
very noise on larger code bases.

Running it on LLVM:
{F5354858} for default configuration
{F5354866} just for llvm/lib/Analysis/ScalarEvolution.cpp, the else-path checker is very noisy!

Reviewers: alexfh, aaron.ballman, hokein

Reviewed By: aaron.ballman

Subscribers: lebedev.ri, Eugene.Zelenko, cfe-commits, mgorny, JDevlieghere, xazax.hun

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D37808

llvm-svn: 318600

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