Commit Graph

1130 Commits

Author SHA1 Message Date
Jonas Devlieghere 97b91307b0
[clang] Disable assertion that can "easily happen"
Disable the assertion for getting a module ID for non-local,
non-imported module. According to the FIXME this can "easily happen" and
indeed, we're hitting this assertion regularly. Disable it until it can
be properly investigated.

rdar://99352728

Differential revision: https://reviews.llvm.org/D136290
2022-10-19 15:08:56 -07:00
Andreas Hollandt 12d007d4ba [clang][modules] Add time traces for AST serialization
Fills gaps in the time trace when precompiled headers are created/loaded.

Reviewed By: jansvoboda11

Differential Revision: https://reviews.llvm.org/D135657
2022-10-19 12:16:30 -07:00
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
Aaron Ballman 60727d8569 [C2x] implement typeof and typeof_unqual
This implements WG14 N2927 and WG14 N2930, which together define the
feature for typeof and typeof_unqual, which get the type of their
argument as either fully qualified or fully unqualified. The argument
to either operator is either a type name or an expression. If given a
type name, the type information is pulled directly from the given name.
If given an expression, the type information is pulled from the
expression. Recursive use of these operators is allowed and has the
expected behavior (the innermost operator is resolved to a type, and
that's used to resolve the next layer of typeof specifier, until a
fully resolved type is determined.

Note, we already supported typeof in GNU mode as a non-conforming
extension and we are *not* exposing typeof_unqual as a non-conforming
extension in that mode, nor are we exposing typeof or typeof_unqual as
a nonconforming extension in other language modes. The GNU variant of
typeof supports a form where the parentheses are elided from the
operator when given an expression (e.g., typeof 0 i = 12;). When in C2x
mode, we do not support this extension.

Differential Revision: https://reviews.llvm.org/D134286
2022-09-28 13:27:52 -04:00
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
Jan Svoboda f35230ae0a [clang][modules][deps] Report modulemaps describing excluded headers
Module map files describing excluded headers do affect compilation. Track them in the compiler, serialize them into the PCM file and report them in the scanner.

Depends on D134222.

Reviewed By: Bigcheese

Differential Revision: https://reviews.llvm.org/D134224
2022-09-22 12:36:05 -07:00
Xiang Li 782ac2182c [HLSL] Support cbuffer/tbuffer for hlsl.
This is first part for support cbuffer/tbuffer.

The format for cbuffer/tbuffer is
BufferType [Name] [: register(b#)] { VariableDeclaration [: packoffset(c#.xyzw)]; ... };

More details at https://docs.microsoft.com/en-us/windows/win32/direct3dhlsl/dx-graphics-hlsl-constants

New keyword 'cbuffer' and 'tbuffer' are added.
New AST node HLSLBufferDecl is added.
Build AST for simple cbuffer/tbuffer without attribute support.

The special thing is variables declared inside cbuffer is exposed into global scope.
So isTransparentContext should return true for HLSLBuffer.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D129883
2022-09-21 10:07:43 -07:00
Richard Howell 3c1b42347b [clang] sort additional module maps when serializing
Sort additional module maps when serializing pcm files. This ensures
the `MODULE_MAP_FILE` record is deterministic across repeated builds.

Reviewed By: benlangmuir

Differential Revision: https://reviews.llvm.org/D133611
2022-09-12 12:00:43 -07:00
Jan Svoboda 002bfdd6b1 [clang][modules] Track affecting modules
When compiling a module, its semantics and Clang's behavior are affected by other modules. These modules are typically the **imported** ones. However, during implicit build, some modules end up being compiled and read without being actually imported. This patch starts tracking such modules and serializing them into `.pcm` files. This enables the dependency scanner to construct explicit compilations that mimic implicit build.

Reviewed By: benlangmuir

Differential Revision: https://reviews.llvm.org/D132430
2022-08-24 11:09:50 -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
Corentin Jabot 127bf44385 [Clang][C++20] Support capturing structured bindings in lambdas
This completes the implementation of P1091R3 and P1381R1.

This patch allow the capture of structured bindings
both for C++20+ and C++17, with extension/compat warning.

In addition, capturing an anonymous union member,
a bitfield, or a structured binding thereof now has a
better diagnostic.

We only support structured bindings - as opposed to other kinds
of structured statements/blocks. We still emit an error for those.

In addition, support for structured bindings capture is entirely disabled in
OpenMP mode as this needs more investigation - a specific diagnostic indicate the feature is not yet supported there.

Note that the rest of P1091R3 (static/thread_local structured bindings) was already implemented.

at the request of @shafik, i can confirm the correct behavior of lldb wit this change.

Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/52720

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D122768
2022-08-04 10:12:53 +02:00
Corentin Jabot a274219600 Revert "[Clang][C++20] Support capturing structured bindings in lambdas"
This reverts commit 44f2baa380.

Breaks self builds and seems to have conformance issues.
2022-08-03 21:00:29 +02:00
Corentin Jabot 44f2baa380 [Clang][C++20] Support capturing structured bindings in lambdas
This completes the implementation of P1091R3 and P1381R1.

This patch allow the capture of structured bindings
both for C++20+ and C++17, with extension/compat warning.

In addition, capturing an anonymous union member,
a bitfield, or a structured binding thereof now has a
better diagnostic.

We only support structured bindings - as opposed to other kinds
of structured statements/blocks. We still emit an error for those.

In addition, support for structured bindings capture is entirely disabled in
OpenMP mode as this needs more investigation - a specific diagnostic indicate the feature is not yet supported there.

Note that the rest of P1091R3 (static/thread_local structured bindings) was already implemented.

at the request of @shafik, i can confirm the correct behavior of lldb wit this change.

Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/52720

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D122768
2022-08-03 20:00:01 +02:00
Argyrios Kyrtzidis 944a86de7c [ASTWriter] Provide capability to output a PCM/PCH file that does not write out information about its output path
This is useful to enable sharing of the same PCH file even when it's intended for a different output path.

The only information this option disables writing is for `ORIGINAL_PCH_DIR` record which is treated as optional and (when present) used as fallback for resolving input file paths relative to it.

Differential Revision: https://reviews.llvm.org/D130710
2022-07-29 15:21:54 -07:00
Argyrios Kyrtzidis a9ae2f2764 [ASTWriter] Replace `const std::string &OutputFile` with `StringRef OutputFile` in some of `ASTWriter` functions, NFC
This is to make it consistent with LLVM's string parameter passing convention.
2022-07-27 23:02:33 -07:00
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
Fangrui Song e690137dde [Support] Change compression::zlib::{compress,uncompress} to use uint8_t *
It's more natural to use uint8_t * (std::byte needs C++17 and llvm has
too much uint8_t *) and most callers use uint8_t * instead of char *.
The functions are recently moved into `llvm::compression::zlib::`, so
downstream projects need to make adaption anyway.
2022-07-13 16:26:54 -07:00
Kazu Hirata 53daa177f8 [clang, clang-tools-extra] Use has_value instead of hasValue (NFC) 2022-07-12 22:47:41 -07:00
Cole Kissane ea61750c35 [NFC] Refactor llvm::zlib namespace
* Refactor compression namespaces across the project, making way for a possible
  introduction of alternatives to zlib compression.
  Changes are as follows:
  * Relocate the `llvm::zlib` namespace to `llvm::compression::zlib`.

Reviewed By: MaskRay, leonardchan, phosek

Differential Revision: https://reviews.llvm.org/D128953
2022-07-08 11:19:07 -07:00
Kazu Hirata 3b7c3a654c Revert "Don't use Optional::hasValue (NFC)"
This reverts commit aa8feeefd3.
2022-06-25 11:56:50 -07:00
Kazu Hirata aa8feeefd3 Don't use Optional::hasValue (NFC) 2022-06-25 11:55:57 -07:00
Kazu Hirata 452db157c9 [clang] Don't use Optional::hasValue (NFC) 2022-06-20 10:51:34 -07:00
Aaron Ballman 69da3b6aea Revert "[OpenMP] atomic compare fail : Parser & AST support"
This reverts commit 232bf8189e.

It broke the sanitize buildbot: https://lab.llvm.org/buildbot/#/builders/5/builds/24074

It also reproduces on Windows debug builds as a crash.
2022-05-25 13:34:34 -04:00
Sunil Kuravinakop 232bf8189e [OpenMP] atomic compare fail : Parser & AST support
This is a support for " #pragma omp atomic compare fail ". It has Parser & AST support for now.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D123235
2022-05-24 23:56:42 -05:00
Mike Rice 9ba937112f [OpenMP] Add parsing/sema support for omp_all_memory reserved locator
Adds support for the reserved locator 'omp_all_memory' for use
in depend clauses with 'out' or 'inout' dependence-types.

Differential Revision: https://reviews.llvm.org/D125828
2022-05-24 10:28:59 -07:00
Sam McCall 1dfd8e99f9 [Serialization] Delta encode locations in expansion sloc entries
This is a 1.9% reduction in PCH size in my measurements.

In abbreviated records, VBR6 seems to be slightl better than VBR8 for locations
that may be delta-encoded (i.e. not the first)

Differential Revision: https://reviews.llvm.org/D125952
2022-05-20 01:05:53 +02:00
Sam McCall 4df795bff7 [Serialization] Delta-encode consecutive SourceLocations in TypeLoc
Much of the size of PCH/PCM files comes from stored SourceLocations.
These are encoded using (almost) their raw value, VBR-encoded. Absolute
SourceLocations can be relatively large numbers, so this commonly takes
20-30 bits per location.

We can reduce this by exploiting redundancy: many "nearby" SourceLocations are
stored differing only slightly and can be delta-encoded.
Randam-access loading of AST nodes constrains how long these sequences
can be, but we can do it at least within a node that always gets
deserialized as an atomic unit.

TypeLoc is implemented in this patch as it's a relatively small change
that shows most of the API.
This saves ~3.5% of PCH size, I have local changes applying this technique
further that save another 3%, I think it's possible to get to 10% total.

Differential Revision: https://reviews.llvm.org/D125403
2022-05-19 09:40:44 +02:00
Richard Howell ee51e9795a [clang] serialize ORIGINAL_PCH_DIR relative to BaseDirectory
This diff changes the serialization of the `ORIGINAL_PCH_DIR`
entry in module files to be serialized relative to the module's
`BaseDirectory`. This will allow for the module to be relocatable
across machines.

The path is restored relative to the module's BaseDirectory on
deserialization.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D124946
2022-05-12 07:31:19 -07:00
Richard Howell f11056943e [clang] serialize SUBMODULE_TOPHEADER relative to BaseDirectory
This diff changes the serialization of the `SUBMODULE_TOPHEADER`
entry in module files to be serialized relative to the module's
`BaseDirectory`. This matches the behavior of the
`SUBMODULE_HEADER` entry and will allow for the module to be
relocatable across machines.

The path is restored relative to the module's `BaseDirectory` on
deserialization.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D124938
2022-05-12 07:29:37 -07:00
Richard Howell 646e502de0 [clang] add -fmodule-file-home-is-cwd
This diff adds a new frontend flag `-fmodule-file-home-is-cwd`.
The behavior of this flag is similar to
`-fmodule-map-file-home-is-cwd` but does not require the module
map files to be modified to have inputs relative to the cwd.
Instead the output modules will have their `BaseDirectory` set
to the cwd and will try and resolve paths relative to that.

The motiviation for this change is to support relocatable pcm
files that are built on different machines with different paths
without having to alter module map files, which is sometimes not
possible as they are provided by 3rd parties.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D124874
2022-05-12 07:27:47 -07:00
Kugan Vivekanandarajah 2deebc0048 [RFC] Add and sort decl to maintain order instead of inserting in order
ASTWriter::associateDeclWithFile shows a lot in clangd perf profile due to O(n^2) behaviour in insertion of DeclIDs in SortedFileDeclIDs. Instead of doing that, this patch just appends it to the DeclIDs vector and sorts them at the end.

Reviewed By: akyrtzi

Differential Revision: https://reviews.llvm.org/D124840
2022-05-03 17:06:22 +01:00
Sam McCall 6035649d4c [Serialization] Remove dead TYPE_FUNCTION_PROTO abbreviation. NFC
It was added in 01b2cb47 but never used.
2022-04-25 21:16:54 +02:00
Jennifer Yu 187ccc66fa [clang][OpenMP5.1] Initial parsing/sema for has_device_addr
Added basic parsing/sema/ support for the 'has_device_addr' clause.

Differential Revision: https://reviews.llvm.org/D123402
2022-04-08 21:19:38 -07:00
Argyrios Kyrtzidis 330268ba34 [Support/Hash functions] Change the `final()` and `result()` of the hashing functions to return an array of bytes
Returning `std::array<uint8_t, N>` is better ergonomics for the hashing functions usage, instead of a `StringRef`:

* When returning `StringRef`, client code is "jumping through hoops" to do string manipulations instead of dealing with fixed array of bytes directly, which is more natural
* Returning `std::array<uint8_t, N>` avoids the need for the hasher classes to keep a field just for the purpose of wrapping it and returning it as a `StringRef`

As part of this patch also:

* Introduce `TruncatedBLAKE3` which is useful for using BLAKE3 as the hasher type for `HashBuilder` with non-default hash sizes.
* Make `MD5Result` inherit from `std::array<uint8_t, 16>` which improves & simplifies its API.

Differential Revision: https://reviews.llvm.org/D123100
2022-04-05 21:38:06 -07:00
David Goldman d9739f29cd Serialize PragmaAssumeNonNullLoc to support preambles
Previously, if a `#pragma clang assume_nonnull begin` was at the
end of a premable with a `#pragma clang assume_nonnull end` at the
end of the main file, clang would diagnose an unterminated begin in
the preamble and an unbalanced end in the main file.

With this change, those errors no longer occur and the case above is
now properly handled. I've added a corresponding test to clangd,
which makes use of preambles, in order to verify this works as
expected.

Differential Revision: https://reviews.llvm.org/D122179
2022-03-31 11:08:01 -04:00
Iain Sandoe f8846229c4 [C++20][Modules][HU 3/5] Emit module macros for header units.
For header units we build the top level module directly from the header
that it represents and macros defined in this TU need to be emitted (when
such a definition is live at the end of the TU).

Differential Revision: https://reviews.llvm.org/D121097
2022-03-26 16:30:40 +00:00
Corentin Jabot 3784e8ccfb [Clang] Fix Unevaluated Lambdas
Unlike other types, when lambdas are instanciated,
they are recreated from scratch.
When an unevaluated lambdas appear in the type of a function,
parameter it is instanciated in the wrong declaration context,
as parameters are transformed before the function.

To support lambda in function parameters, we try to
compute whether they are dependant without looking at the
declaration context.

This is a short term stopgap solution to avoid clang
iceing. A better fix might be to inject some kind of
transparent declaration with correctly computed dependency
for function parameters, variable templates, etc.

Fixes https://github.com/llvm/llvm-project/issues/50376
Fixes https://github.com/llvm/llvm-project/issues/51414
Fixes https://github.com/llvm/llvm-project/issues/51416
Fixes https://github.com/llvm/llvm-project/issues/51641
Fixes https://github.com/llvm/llvm-project/issues/54296

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D121532
2022-03-25 19:16:45 +01:00
Hubert Tong ce21c926f8 [Clang] Work with multiple pragmas weak before definition
Update `WeakUndeclaredIdentifiers` to hold a collection of weak
aliases per identifier instead of only one.

This also allows the "used" state to be removed from `WeakInfo`
because it is really only there as an alternative to removing
processed map entries, and we can represent that using an empty set
now. The serialization code is updated for the removal of the field.
Additionally, a PCH test is added for the new functionality.

The records are grouped by the "target" identifier, which was already
being used as a key for lookup purposes. We also store only one record
per alias name; combined, this means that diagnostics are grouped by
the "target" and limited to one per alias (which should be acceptable).

Fixes PR28611.
Fixes llvm/llvm-project#28985.

Reviewed By: aaron.ballman, cebowleratibm

Differential Revision: https://reviews.llvm.org/D121927

Co-authored-by: Rachel Craik <rcraik@ca.ibm.com>
Co-authored-by: Jamie Schmeiser <schmeise@ca.ibm.com>
2022-03-24 20:17:49 -04:00
Benjamin Kramer 5d2ce7663b Use llvm::append_range instead of push_back loops where applicable. NFCI. 2022-03-18 01:25:34 +01:00
Yonghong Song 3251ba2d0f [Attr] Fix a btf_type_tag AST generation
Current ASTContext.getAttributedType() takes attribute kind,
ModifiedType and EquivType as the hash to decide whether an AST node
has been generated or note. But this is not enough for btf_type_tag
as the attribute might have the same ModifiedType and EquivType, but
still have different string associated with attribute.

For example, for a data structure like below,
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag2"))) __attribute__((btf_type_tag("tag4"))) *b;
  };
The current ASTContext.getAttributedType() will produce
an AST similar to below:
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *b;
  };
and this is incorrect.

It is very difficult to use the current AttributedType as it is hard to
get the tag information. To fix the problem, this patch introduced
BTFTagAttributedType which is similar to AttributedType
in many ways but with an additional BTFTypeTagAttr. The tag itself can
be retrieved with BTFTypeTagAttr.
With the new BTFTagAttributed type, the debuginfo code can be greatly
simplified compared to previous TypeLoc based approach.

Differential Revision: https://reviews.llvm.org/D120296
2022-03-16 08:46:52 -07:00
Fangrui Song 407c721ceb [Support] Change zlib::compress to return void
With a sufficiently large output buffer, the only failure is Z_MEM_ERROR.
Check it and call the noreturn report_bad_alloc_error if applicable.
resize_for_overwrite may call report_bad_alloc_error as well.

Now that there is no other error type, we can replace the return type with void
and simplify call sites.

Reviewed By: ikudrin

Differential Revision: https://reviews.llvm.org/D121512
2022-03-14 11:38:04 -07:00
Jan Svoboda b45888e959 [clang][modules] Report module maps affecting `no_undeclared_includes` modules
Since D106876, PCM files don't report module maps as input files unless they contributed to the compilation.

Reporting only module maps of (transitively) imported modules is not enough, though. For modules marked with `[no_undeclared_includes]`, other module maps affect the compilation by introducing anti-dependencies.

This patch makes sure such module maps are being reported as input files.

Depends on D120463.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D120464
2022-03-07 10:47:46 +01:00
Adam Czachorowski 8f4ea36bfe [clang] Improve laziness of resolving module map headers.
clang has support for lazy headers in module maps - if size and/or
modtime and provided in the cppmap file, headers are only resolved when
an include directive for a file with that size/modtime is encoutered.

Before this change, the lazy resolution was all-or-nothing per module.
That means as soon as even one file in that module potentially matched
an include, all lazy files in that module were resolved. With this
change, only files with matching size/modtime will be resolved.

The goal is to avoid unnecessary stat() calls on non-included files,
which is especially valuable on networked file systems, with higher
latency.

Differential Revision: https://reviews.llvm.org/D120569
2022-03-01 15:56:23 +01:00
Iain Sandoe c9cc8035eb [C++20][Modules][2/8] Add enumerations for partition modules and stream them.
This is an initial enabling patch for module partition support.
We add enumerations for partition interfaces/implementations.

This means that the module kind enumeration now occupies three
bits, so the AST streamer is adjusted for this.  Adding one bit there
seems preferable to trying to overload the meanings of existing
kinds (and we will also want to add a C++20 header unit case later).

Differential Revision: https://reviews.llvm.org/D114714
2022-02-22 10:08:15 +00:00
Alex Lorenz 00cd6c0420 [Preprocessor] Reduce the memory overhead of `#define` directives (Recommit)
Recently we observed high memory pressure caused by clang during some parallel builds.
We discovered that we have several projects that have a large number of #define directives
in their TUs (on the order of millions), which caused huge memory consumption in clang due
to a lot of allocations for MacroInfo. We would like to reduce the memory overhead of
clang for a single #define to reduce the memory overhead for these files, to allow us to
reduce the memory pressure on the system during highly parallel builds. This change achieves
that by removing the SmallVector in MacroInfo and instead storing the tokens in an array
allocated using the bump pointer allocator, after all tokens are lexed.

The added unit test with 1000000 #define directives illustrates the problem. Prior to this
change, on arm64 macOS, clang's PP bump pointer allocator allocated 272007616 bytes, and
used roughly 272 bytes per #define. After this change, clang's PP bump pointer allocator
allocates 120002016 bytes, and uses only roughly 120 bytes per #define.

For an example test file that we have internally with 7.8 million #define directives, this
change produces the following improvement on arm64 macOS: Persistent allocation footprint for
this test case file as it's being compiled to LLVM IR went down 22% from 5.28 GB to 4.07 GB
and the total allocations went down 14% from 8.26 GB to 7.05 GB. Furthermore, this change
reduced the total number of allocations made by the system for this clang invocation from
1454853 to 133663, an order of magnitude improvement.

The recommit fixes the LLDB build failure.

Differential Revision: https://reviews.llvm.org/D117348
2022-02-14 09:27:44 -08:00
Alex Lorenz 3f05192c4c Revert "[Preprocessor] Reduce the memory overhead of `#define` directives"
This reverts commit 0d9b91524e.

This change broke LLDB's build. I will need to recommit after fixing LLDB.
2022-02-11 15:53:16 -08:00
Alex Lorenz 0d9b91524e [Preprocessor] Reduce the memory overhead of `#define` directives
Recently we observed high memory pressure caused by clang during some parallel builds.
We discovered that we have several projects that have a large number of #define directives
in their TUs (on the order of millions), which caused huge memory consumption in clang due
to a lot of allocations for MacroInfo. We would like to reduce the memory overhead of
clang for a single #define to reduce the memory overhead for these files, to allow us to
reduce the memory pressure on the system during highly parallel builds. This change achieves
that by removing the SmallVector in MacroInfo and instead storing the tokens in an array
allocated using the bump pointer allocator, after all tokens are lexed.

The added unit test with 1000000 #define directives illustrates the problem. Prior to this
change, on arm64 macOS, clang's PP bump pointer allocator allocated 272007616 bytes, and
used roughly 272 bytes per #define. After this change, clang's PP bump pointer allocator
allocates 120002016 bytes, and uses only roughly 120 bytes per #define.

For an example test file that we have internally with 7.8 million #define directives, this
change produces the following improvement on arm64 macOS: Persistent allocation footprint for
this test case file as it's being compiled to LLVM IR went down 22% from 5.28 GB to 4.07 GB
and the total allocations went down 14% from 8.26 GB to 7.05 GB. Furthermore, this change
reduced the total number of allocations made by the system for this clang invocation from
1454853 to 133663, an order of magnitude improvement.

Differential Revision: https://reviews.llvm.org/D117348
2022-02-11 15:01:10 -08:00
Jan Svoboda f720272330 [clang][lex] Include tracking: simplify and move to preprocessor
This patch replaces the exact include count of each file in `HeaderFileInfo` with a set of included files in `Preprocessor`.

The number of includes isn't a property of a header file but rather a preprocessor state. The exact number of includes is not used anywhere except statistic tracking.

Reviewed By: vsapsai

Differential Revision: https://reviews.llvm.org/D114095
2022-01-26 15:56:26 +01:00
Haojian Wu ab3f100bec Reland (2) "[AST] Add RParen loc for decltype AutoTypeloc.""
The patch was reverted because it caused a crash during PCH build -- we
missed to update the RParenLoc in TreeTransform<Derived>::TransformAutoType.

This relands 55d96ac and 37ec65e with a test and fix.
2022-01-17 11:33:11 +01:00