Commit Graph

1641 Commits

Author SHA1 Message Date
Volodymyr Sapsai 2662009c87 [ODRHash] Hash `ObjCMethodDecl` and diagnose discovered mismatches.
Differential Revision: https://reviews.llvm.org/D130325
2022-10-17 18:48:24 -07:00
Volodymyr Sapsai 9c79eab7fd [ODRHash] Hash `ObjCProtocolDecl` and diagnose discovered mismatches.
Differential Revision: https://reviews.llvm.org/D130324
2022-10-17 16:29:52 -07:00
Kai Luo e231a58013 [clang][Module][AIX] Mark test unsupported since objc doesn't have xcoff support
Fixed error
```
Command Output (stderr):
--
fatal error: error in backend: Objective-C support is unimplemented for object file format
```
Source code in `clang/lib/CodeGen/CGObjCMac.cpp:5080`

```
  case llvm::Triple::Wasm:
  case llvm::Triple::GOFF:
  case llvm::Triple::SPIRV:
  case llvm::Triple::XCOFF:
  case llvm::Triple::DXContainer:
    llvm::report_fatal_error(
        "Objective-C support is unimplemented for object file format");
  }

```

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D135848
2022-10-13 12:03:55 +08:00
Volodymyr Sapsai a6ebd3083d [modules] Allow to validate system headers less often with `-fmodules-validate-once-per-build-session`.
Make flags `-fmodules-validate-system-headers` and
`-fmodules-validate-once-per-build-session` orthogonal, so they have
their own independent responsibilities - if system headers should be
validated and how often.

rdar://87988889

Differential Revision: https://reviews.llvm.org/D135232
2022-10-12 11:10:08 -07:00
Chuanqi Xu 0c4f0bf40d [C++20] [Modules] Only allow redeclarations in partitions if they are in the same module
Closes https://github.com/llvm/llvm-project/issues/58196.

The root cause for the problem is an oversight in
https://reviews.llvm.org/D127624, which allows the redeclarations in
partitions. However, we took a mistake there that we should only allow
it if the redeclarations in the one same module instead of return
directly if either the redeclaration lives in a partition. The original
implementation makes no sense and I believe it was an oversight.
2022-10-08 17:44:04 +08:00
Chuanqi Xu 9974ed8049 [C++20] [Modules] Remove assertion of current module when acting on import
Closes https://github.com/llvm/llvm-project/issues/58199

Previously, when we act on a import statement, we'll assume there is a
module declaration in the current TU if the command line tells us we're
compiling a module unit. This makes since on valid codes. However, for
invalid codes, it is possible. See
https://github.com/llvm/llvm-project/issues/58199 for example.

This patch removes the assertion. And the assertion is a noop and it
should be safe to remove it.
2022-10-08 16:44:51 +08:00
Jan Svoboda 5865476879 [clang][modules] Fix handling of `ModuleHeaderRole::ExcludedHeader`
This is a follow-up to D134224. The original patch added new `ExcludedHeader` enumerator to `ModuleMap::ModuleHeaderRole` and started associating headers with the modules they were excluded from. This was necessary to consider their module maps as "affecting" in certain situations and in turn serialize them into the PCM.

The association of the header and module needs to be handled when deserializing the PCM as well, though. This patch fixes a potential assertion failure and a regression. This essentially reverts parts of feb54b6ded.

Reviewed By: Bigcheese

Differential Revision: https://reviews.llvm.org/D135381
2022-10-06 16:20:24 -07:00
Ben Langmuir 5ea78c4113 [clang] Update ModuleMap::getModuleMapFile* to use FileEntryRef
Update SourceManager::ContentCache::OrigEntry to keep the original
FileEntryRef, and use that to enable ModuleMap::getModuleMapFile* to
return the original FileEntryRef. This change should be NFC for
most users of SourceManager::ContentCache, but it could affect behaviour
for users of getNameAsRequested such as in compileModuleImpl. I have not
found a way to detect that difference without additional functional
changes, other than incidental cases like changes from / to \ on
Windows so there is no new test.

Differential Revision: https://reviews.llvm.org/D135220
2022-10-05 13:12:43 -07:00
Alex Langford 266ec801fb [clang][DebugInfo] Respect fmodule-file-home-is-cwd in skeleton CUs for clang modules
When -fmodule-file-home-is-cwd and the path to the PCM is relative, we
shouldn't assume that the path to the PCM is relative to the modulemap
that produced it. To respect the option -fmodule-file-home-is-cwd, we
should assume the path is relative to the current working directory.

Reviewed By: rmaz

Differential Revision: https://reviews.llvm.org/D134911
2022-10-04 11:25:43 -07:00
Chuanqi Xu 1aaba40dcb [C++] [Modules] Add a test case for mocking implementation for std modules
I found this with the patch: https://reviews.llvm.org/D131858. It breaks
my local implementation but not the in-tree test cases. So I reduce the
failure and submit the test case. The more testing should be always
good.
2022-09-23 15:20:46 +08:00
Jan Svoboda 20fa87c7e8 [clang][modules][deps] Preserve module map load order
In `ASTWriter`, input files are sorted based on whether they are system or user. The current implementation used single `std::queue` with `push_back` and `push_front`. This resulted in the user files being reversed.

This patch fixes that by keeping the system/user distinction, but otherwise serializing files in the order they were loaded by the `SourceManager`. This is then used in the dependency scanner to report module map dependencies in the correct order.

Depends on D134224.

Reviewed By: Bigcheese

Differential Revision: https://reviews.llvm.org/D134248
2022-09-22 12:54:51 -07:00
Erich Keane babdef27c5 Re-apply "Deferred Concept Instantiation Implementation"
This reverts commit 95d94a6775.

This implements the deferred concepts instantiation, which should allow
the libstdc++ ranges to properly compile, and for the CRTP to work for
constrained functions.

Since the last attempt, this has fixed the issues from @wlei and
@mordante.

Differential Revision: https://reviews.llvm.org/D126907
2022-09-22 05:53:59 -07:00
Volodymyr Sapsai e12f6c26c3 [modules] Fix error "malformed or corrupted AST file: 'SourceLocation remap refers to unknown module...'".
When a framework can be found at a new location, all references to it in
the module cache become outdated. When we try to load such outdated .pcm
file, we shouldn't change any already loaded and processed modules.

If `Module` has `ASTFile`, it means we've read its AST block already and
it is too late to undo that. If `ASTFile` is `None`, there is no value
in setting it to `None` again. So we don't reset `ASTFile` in
`ModuleManager::removeModules` at all.

rdar://97216258

Differential Revision: https://reviews.llvm.org/D134249
2022-09-20 17:55:37 -07:00
Colin Cross 7fe475756b Set HOME for tests that use module cache path
Getting the default module cache path calls llvm::sys::path::cache_directory,
which calls home_directory, which checks the HOME environment variable
before falling back to getpwuid.  When compiling against musl libc,
which does not support NSS, and running on a machine that doesn't have
the current user in /etc/passwd due to NSS, no home directory can
be found.  Set the HOME environment variable in the tests to avoid
depending on getpwuid.

Reviewed By: pirama, srhines

Differential Revision: https://reviews.llvm.org/D132984
2022-09-15 23:58:57 +00:00
Alexander Shaposhnikov b6965f7246 [IR] Add alignment for llvm.threadlocal.address
This diff sets the alignment attribute for the return value
and the argument of llvm.threadlocal.address.

(https://github.com/llvm/llvm-project/issues/57438)

Test plan: ninja check-all

Differential revision: https://reviews.llvm.org/D133741
2022-09-13 23:10:55 +00:00
Ben Langmuir 4a72459ed6 Revert "[clang][test] Disallow using the default module cache path in lit tests"
This reverts commit d96f526196.

Some systems do not support `env -u`.
2022-09-12 13:10:22 -07:00
Ben Langmuir d96f526196 [clang][test] Disallow using the default module cache path in lit tests
Make the default module cache path invalid when running lit tests so
that tests are forced to provide a cache path. This avoids accidentally
escaping to the system default location, and would have caught the
failure recently found in ClangScanDeps/multiple-commands.c.

Differential Revision: https://reviews.llvm.org/D133622
2022-09-12 09:54:56 -07:00
Richard Smith a002063de3 Enforce module decl-use restrictions and private header restrictions in textual headers
Per the documentation, these restrictions were intended to apply to textual headers but previously this didn't work because we decided there was no requesting module when the `#include` was in a textual header.

A `-cc1` flag is provided to restore the old behavior for transitionary purposes.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D132779
2022-09-06 17:12:57 -07:00
Fangrui Song 83ea47acd7 [test] Make tests pass regardless of gnu++14/gnu++17 default
GCC from 11 onwards defaults to -std=gnu++17 for C++ source files. We want to do the same
(https://discourse.llvm.org/t/c-objc-switch-to-gnu-17-as-the-default-dialect/64360).
Split RUN lines, adjust `-verify`, or add `__cplusplus < 201703L` or `-Wno-dynamic-exception-spec`,
so that tests will pass regardless of gnu++14/gnu++17 default.

We have a desire to mark a test compatible with multiple language standards.
There are ongoing discussions how to add markers in the long term:

* https://discourse.llvm.org/t/iterating-lit-run-lines/62596
* https://discourse.llvm.org/t/lit-run-a-run-line-multiple-times-with-different-replacements/64932

As a workaround in the short term, add lit substitutions `%std_cxx98-`,
`%std_cxx11-14`, etc. They can be used for tests which work across multiple
language standards. If a range has `n` standards, run lit multiple times, with
`LIT_CLANG_STD_GROUP=0`, `LIT_CLANG_STD_GROUP=1`, etc to cover all `n` standards.

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D131464
2022-09-04 05:29:32 +00:00
Richard Smith 632e1e9fd8 Work around Windows buildbot failure.
-fmodules-local-submodule-visibility and -fdelayed-template-parsing
don't work properly together because the template is parsed in the
visibility context of the wrong module.
2022-09-02 19:09:15 -07:00
Richard Smith 220c2cb0a8 Attempt to make AIX bot happier. 2022-09-02 18:43:27 -07:00
Richard Smith b484256f59 Add driver test for -fmodule-name and -fmodule-map-file use without -fmodules. 2022-09-02 16:08:30 -07:00
Mikhail Goncharov 0f95b2b060 [clang] update pr27699 test to make headers different (NFC)
some build systems treat those headers as identical, causing a warning
2022-08-31 13:12:28 +02:00
Jan Svoboda 94e64df576 [clang][modules] Consider M affecting after mapping M.Private to M_Private
When Clang encounters `@import M.Private` during implicit build, it precompiles module `M` and looks through its submodules. If the `Private` submodule is not found, Clang assumes `@import M_Private`. In the dependency scanner, we don't capture the dependency on `M`, since it's not imported. It's an affecting module, though: compilation of the import statement will fail when implicit modules are disabled and `M` is not precompiled and explicitly provided. This patch fixes that.

Depends on D132430.

Reviewed By: benlangmuir

Differential Revision: https://reviews.llvm.org/D132502
2022-08-24 14:36:06 -07:00
Iain Sandoe fee3cccc6c [C++20][Modules] Improve handing of Private Module Fragment diagnostics.
This adds a check for exported inline functions, that there is a definition in
the definition domain (which, in practice, can only be the module purview but
before any PMF starts) since the PMF definition domain cannot contain exports.

This is:
[dcl.inline]/7
If an inline function or variable that is attached to a named module is declared in
a definition domain, it shall be defined in that domain.

The patch also amends diagnostic output by excluding the PMF sub-module from the
set considered as sources of missing decls.  There is no point in telling the user
that the import of a PMF object is missing - since such objects are never reachable
to an importer.  We still show the definition (as unreachable), to help point out
this.

Differential Revision: https://reviews.llvm.org/D128328
2022-08-21 10:19:46 +01:00
Iain Sandoe a2dd6130d4 [clang][Modules] Fix a regression in handling missing framework headers.
The commit of af2d11b1d5 missed a case where
the value of a suggested module needed to be reset to nullptr.  Fixed thus
and added a testcase to cover the circumstance.
2022-08-19 09:13:22 +01:00
Chuanqi Xu 0bc993edf4 [AST] [Modules] Introduce Decl::getNonTransparentDeclContext to handle exported friends
Closing https://github.com/llvm/llvm-project/issues/56826.

The root cause for pr56826 is: when we collect the template args for the
friend, we need to judge if the friend lives in file context. However,
if the friend lives in ExportDecl lexically, the judgement here is
invalid.

The solution is easy. We should judge the non transparent context and
the ExportDecl is transparent context. So the solution should be good.

A main concern may be the patch doesn't handle all the places of the
same defect. I think it might not be bad since the patch itself should
be innocent.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D131651
2022-08-12 11:50:35 +08:00
Ilya Biryukov 07529996d9 [Sema] Merge variable template specializations
Clang used to produce redefinition errors, see tests for examples.

Reviewed By: ChuanqiXu

Differential Revision: https://reviews.llvm.org/D131258
2022-08-09 12:17:41 +02:00
Argyrios Kyrtzidis 7b12e561ac [test/Modules/cxx20-export-import.cpp] Pre-clean the modules cache directory of the test, NFC 2022-08-05 17:27:43 -07:00
Argyrios Kyrtzidis 6635f48e4a [Serialization] Remove `ORIGINAL_PCH_DIR` record
Use of `ORIGINAL_PCH_DIR` record has been superseeded by making PCH/PCM files with relocatable paths at write time.
Removing this record is useful for producing an output-path-independent PCH file and enable sharing of the same PCH file even
when it was intended for a different output path.

Differential Revision: https://reviews.llvm.org/D131124
2022-08-05 15:40:33 -07:00
Ben Langmuir fb89cc0ddb [clang][modules] Don't depend on sharing FileManager during module build
Sharing the FileManager between the importer and the module build should
only be an optimization. Add a cc1 option -fno-modules-share-filemanager
to allow us to test this. Fix the path to modulemap files, which
previously depended on the shared FileManager when using path mapped to
an external file in a VFS.

Differential Revision: https://reviews.llvm.org/D131076
2022-08-05 12:24:40 -07:00
Chuanqi Xu bacdf80f42 Use @llvm.threadlocal.address intrinsic to access TLS variable
This is successor for D125291. This revision would try to use
@llvm.threadlocal.address in clang to access TLS variable. The reason
why the OpenMP tests contains a lot of change is that they uses
utils/update_cc_test_checks.py to update their tests.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D129833
2022-08-01 11:05:00 +08:00
Chuanqi Xu 4d9251bd78 [C++20] [Modules] Merge same concept decls in global module fragment
According to [basic.def.odr]p14, the same redeclarations in different TU
but not attached to a named module are allowed. But we didn't take care
of concept decl for this condition. This patch tries to fix this
problem.

Reviewed By: ilya-biryukov

Differention Revision: https://reviews.llvm.org/D130614
2022-07-29 10:50:27 +08:00
Chuanqi Xu fe1887da36 [NFC] [C++20] [Modules] Add tests for merging redefinitions in modules
Add tests for detecting redefinitions in C++20 modules. Some of these
may be covered by other tests. But more tests should be always good.
2022-07-28 11:32:47 +08:00
Ilya Biryukov 42f87bb62d [Sema] Return primary merged decl as canonical for concepts
Otherwise we get invalid results for ODR checks. See changed test for an
example: despite the fact that we merge the first concept, its **uses**
were considered different by `Profile`, leading to redefinition errors.

After this change, canonical decl for a concept can come from a
different module and may not be visible. This behavior looks suspicious,
but does not break any tests. We might want to add a mechanism to make
the canonical concept declaration visible if we find code that relies on
this invariant.

Additionally make sure we always merge with the canonical declaration to
avoid chains of merged concepts being reported as redefinitions. An
example was added to the test.

Also change the order of includes in the test. Importing a moduralized
header before its textual part causes the include guard macro to be
exported and the corresponding `#include` becomes a no-op.

Reviewed By: ChuanqiXu

Differential Revision: https://reviews.llvm.org/D130585
2022-07-27 12:31:20 +02:00
Matheus Izvekov 15f3cd6bfc
[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
2022-07-27 11:10:54 +02:00
Chuanqi Xu a2772fc806 [C++20] [Modules] Disable preferred_name when writing a C++20 Module interface
Currently, the use of preferred_name would block implementing std
modules in libcxx. See https://github.com/llvm/llvm-project/issues/56490
for example.
The problem is pretty hard and it looks like we couldn't solve it in a
short time. So we sent this patch as a workaround to avoid blocking us
to modularize STL. This is intended to be fixed properly in the future.

Reviewed By: erichkeane, aaron.ballman, tahonermann

Differential Revision: https://reviews.llvm.org/D130331
2022-07-26 23:58:07 +08:00
Chuanqi Xu 99daf6b263 [C++20] [Modules] Don't handle no linkage entities when overloading
The original implementation uses `ND->getFormalLinkage() <=
Linkage::InternalLinkage`. It is not right since the spec only says
internal linkage and it doesn't mention 'no linkage'. This matters when
we consider constructors. According to [class.ctor.general]p1,
constructors have no name so constructors have no linkage too.
2022-07-26 21:07:41 +08:00
Chuanqi Xu 15ddc09ef9 [C++20] [Modules] Handle linkage properly for specializations when overloading
Currently, the semantics of linkage in clang is slightly
different from the semantics in C++ spec. In C++ spec, only names
have linkage. So that all entities of the same should share
one linkage. But in clang, different entities of the same could
have different linkage.

It would break a use case where the template have external linkage and
its specialization have internal linkage due to its type argument is
internal linkage. The root cause is that the semantics of internal
linkage in clang is a mixed form of internal linkage and TU-local in
C++ spec. It is hard to solve the root problem and I tried to add a
workaround inplace.
2022-07-26 18:30:48 +08:00
Ilya Biryukov 59179d72b2 [Sema] Merge C++20 concept definitions from different modules in same TU
Currently the C++20 concepts are only merged in `ASTReader`, i.e. when
coming from different TU. This can causes ambiguious reference errors when
trying to access the same concept that should otherwise be merged.

Please see the added test for an example.

Note that we currently use `ASTContext::isSameEntity` to check for ODR
violations. However, it will not check that concept requirements match.
The same issue holds for mering concepts from different TUs, I added a
FIXME and filed a GH issue to track this:
https://github.com/llvm/llvm-project/issues/56310

Reviewed By: ChuanqiXu

Differential Revision: https://reviews.llvm.org/D128921
2022-07-25 14:43:38 +02:00
Aaron Ballman 7068aa9841 Strengthen -Wint-conversion to default to an error
Clang has traditionally allowed C programs to implicitly convert
integers to pointers and pointers to integers, despite it not being
valid to do so except under special circumstances (like converting the
integer 0, which is the null pointer constant, to a pointer). In C89,
this would result in undefined behavior per 3.3.4, and in C99 this rule
was strengthened to be a constraint violation instead. Constraint
violations are most often handled as an error.

This patch changes the warning to default to an error in all C modes
(it is already an error in C++). This gives us better security posture
by calling out potential programmer mistakes in code but still allows
users who need this behavior to use -Wno-error=int-conversion to retain
the warning behavior, or -Wno-int-conversion to silence the diagnostic
entirely.

Differential Revision: https://reviews.llvm.org/D129881
2022-07-22 15:24:54 -04:00
Chuanqi Xu 6d9b84797c [C++20] [Modules] Handle reachability for partial specialization
Previously we don't catch the reachability for partial specialization.
Handle them in this patch.
2022-07-22 17:03:38 +08:00
Volodymyr Sapsai 381fcaa136 [modules] Replace `-Wauto-import` with `-Rmodule-include-translation`.
Diagnostic for `-Wauto-import` shouldn't be a warning because it doesn't
represent a potential problem in code that should be fixed. And the
emitted fix-it is likely to trigger `-Watimport-in-framework-header`
which makes it challenging to have a warning-free codebase. But it is
still useful to see how include directives are translated into modular
imports and which module a header belongs to, that's why keep it as a remark.

Keep `-Wauto-import` for now to allow a gradual migration for codebases
using `-Wno-auto-import`, e.g., `-Weverything -Wno-auto-import`.

rdar://79594287

Differential Revision: https://reviews.llvm.org/D130138
2022-07-21 17:42:04 -07:00
Chuanqi Xu ea623af7c9 [C++20] [Modules] Avoid inifinite loop when iterating default args
Currently, clang may meet an infinite loop in a very tricky case when it
iterates the default args. This patch tries to fix this by adding a
`fixed` check.
2022-07-21 17:25:05 +08:00
Chuanqi Xu 4983fdfec0 [C++20] [Modules] Handle reachability for deduction guide
Previously, we forget to handle reachability for deduction guide.
The deduction guide is a hint to the compiler. And the deduction guide
should be able to use if the corresponding template decl is reachable.
2022-07-18 15:46:26 +08:00
Nikita Popov 2a721374ae [IR] Don't use blockaddresses as callbr arguments
Following some recent discussions, this changes the representation
of callbrs in IR. The current blockaddress arguments are replaced
with `!` label constraints that refer directly to callbr indirect
destinations:

    ; Before:
    %res = callbr i8* asm "", "=r,r,i"(i8* %x, i8* blockaddress(@test8, %foo))
    to label %asm.fallthrough [label %foo]
    ; After:
    %res = callbr i8* asm "", "=r,r,!i"(i8* %x)
    to label %asm.fallthrough [label %foo]

The benefit of this is that we can easily update the successors of
a callbr, without having to worry about also updating blockaddress
references. This should allow us to remove some limitations:

* Allow unrolling/peeling/rotation of callbr, or any other
  clone-based optimizations
  (https://github.com/llvm/llvm-project/issues/41834)
* Allow duplicate successors
  (https://github.com/llvm/llvm-project/issues/45248)

This is just the IR representation change though, I will follow up
with patches to remove limtations in various transformation passes
that are no longer needed.

Differential Revision: https://reviews.llvm.org/D129288
2022-07-15 10:18:17 +02:00
Chuanqi Xu 2f1555fb11 [C++20] [Modules] Handle reachability for enum class
In previous reachability patch, we missed the case for enum class.
Trying to handle it in this patch and add the corresponding tests.
2022-07-15 15:57:04 +08:00
Jonas Devlieghere 888673b6e3
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit 7c51f02eff 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.
2022-07-14 21:17:48 -07:00
Matheus Izvekov 7c51f02eff
[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
2022-07-15 04:16:55 +02:00
Jonas Devlieghere 3968936b92
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit bdc6974f92 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/
2022-07-13 09:20:30 -07:00