Commit Graph

706 Commits

Author SHA1 Message Date
Shafik Yaghmour a0d6105162 [Clang] Fix handling of Max from getValueRange(...) in IntExprEvaluator::VisitCastExpr(...)
This is a follow-up to D130058 to fix how we handle the Max value we obtain from
getValueRange(...) in IntExprEvaluator::VisitCastExpr(...) which in the case of
an enum that contains an enumerator with the max integer value will overflow by
one.

The fix is to decrement the value of Max and use slt and ult for comparison Vs
sle and ule.`

Differential Revision: https://reviews.llvm.org/D130811
2022-07-29 19:17:42 -07:00
Aaron Ballman d8352abd3a Diagnose use of _Noreturn on a struct/union field
C99 6.7.4p2 clarifies that a function specifier can only be used in the
declaration of a function. _Noreturn is a function specifier, so it is
a constraint violation to write it on a structure or union field, but
we missed that case.

Fixes #56800
2022-07-29 13:18:44 -04:00
Shafik Yaghmour b364535304 [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values
DR2338 clarified that it was undefined behavior to set the value outside the
range of the enumerations values for an enum without a fixed underlying type.

We should diagnose this with a constant expression context.

Differential Revision: https://reviews.llvm.org/D130058
2022-07-28 15:27:50 -07:00
Muhammad Usman Shahid 0cc3c184c7 Missing tautological compare warnings due to unary operators
The patch mainly focuses on the lack of warnings for
-Wtautological-compare. It works fine for positive numbers but doesn't
for negative numbers. This is because the warning explicitly checks for
an IntegerLiteral AST node, but -1 is represented by a UnaryOperator
with an IntegerLiteral sub-Expr.

For the below code we have warnings:

if (0 == (5 | x)) {}

but not for

if (0 == (-5 | x)) {}

This patch changes the analysis to not look at the AST node directly to
see if it is an IntegerLiteral, but instead attempts to evaluate the
expression to see if it is an integer constant expression. This handles
unary negation signs, but also handles all the other possible operators
as well.

Fixes #42918
Differential Revision: https://reviews.llvm.org/D130510
2022-07-28 07:45:28 -04:00
Shafik Yaghmour 28cd7f86ed Revert "[Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values"
This reverts commit a3710589f2.
2022-07-27 15:31:41 -07:00
Shafik Yaghmour a3710589f2 [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values
DR2338 clarified that it was undefined behavior to set the value outside the
range of the enumerations values for an enum without a fixed underlying type.

We should diagnose this with a constant expression context.

Differential Revision: https://reviews.llvm.org/D130058
2022-07-27 14:59:35 -07:00
Tom Stellard 809855b56f Bump the trunk major version to 16 2022-07-26 21:34:45 -07:00
Shilei Tian 114df244ec [Clang][Doc] Update the release note for clang
Add the support for `atomic compare` and `atomic compare capture` in the
release note of clang.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D129211
2022-07-26 15:39:21 -04:00
Danny Mösch 4e94f66531 [clang] Pass FoundDecl to DeclRefExpr creator for operator overloads
Without the "found declaration" it is later not possible to know where the operator declaration
was brought into the scope calling it.

The initial motivation for this fix came from #55095. However, this also has an influence on
`clang -ast-dump` which now prints a `UsingShadow` attribute for operators only visible through
`using` statements. Also, clangd now correctly references the `using` statement instead of the
operator directly.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D129973
2022-07-26 21:22:18 +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
Roman Rusyaev fec5ff2a32 [Clang] [P2025] Analyze only potential scopes for NRVO
Before the patch we calculated the NRVO candidate looking at the
variable's whole enclosing scope. The research in [P2025] shows that
looking at the variable's potential scope is better and covers more
cases where NRVO would be safe and desirable.

Many thanks to @Izaron for the original implementation.

Reviewed By: ChuanqiXu

Differential Revision: https://reviews.llvm.org/D119792
2022-07-26 18:57:10 +08:00
Chuanqi Xu c73adbad6a [clang] [docs] Update the changes of C++20 Modules in clang15
Since clang15 is going to be branched in July 26, and C++ modules still
lack an update on ReleaseNotes. Although it is not complete yet, I think
it would be better to add one since we've done many works for C++20
Modules in clang15.

Differential Revision: https://reviews.llvm.org/D129138
2022-07-26 18:47:53 +08:00
Tom Stellard bc39d7bdd4 libclang.so: Make SONAME the same as LLVM version
This partially reverts c7b3a91017.  Having
libclang.so with a different SONAME than the other LLVM libraries was
causing a lot of confusion for users.  Also, this change did not really
acheive it's purpose of allowing apps to use newer versions of
libclang.so without rebuilding, because a new version of libclang.so
requires a new version of libLLVM.so, which does not have a stable ABI.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D129160
2022-07-25 22:03:34 -07:00
Shafik Yaghmour aea82d4551 [Clang] Fix how we set the NumPositiveBits on an EnumDecl to cover the case of single enumerator with value zero or an empty enum
Currently in Sema::ActOnEnumBody(...) when calculating NumPositiveBits we miss
the case where there is only a single enumerator with value zero and the case of
an empty enum. In both cases we end up with zero positive bits when in fact we
need one bit to store the value zero.

This PR updates the calculation to account for these cases.

Differential Revision: https://reviews.llvm.org/D130301
2022-07-25 16:01:01 -07:00
Igor Zhukov ba49d39b20 Use `<stdatomic.h>` with MSVC and C++
and use fallback only for C.

It fixes the isssue with clang-cl:

```
#include <stdatomic.h>
#include <stdbool.h>
#ifdef __cplusplus
#include <atomic>
using namespace std;
#endif

int main() {
    atomic_bool b = true;
}
```

```
$ clang-cl /TC main.cpp
# works
```
```
$ clang-cl /TP /std:c++20 main.cpp

stdatomic.h(70,6): error: conflicting types for 'atomic_thread_fence'
void atomic_thread_fence(memory_order);
     ^
atomic(166,24): note: previous definition is here
extern "C" inline void atomic_thread_fence(const memory_order _Order) noexcept {

...

fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
```
Many errors but
`<stdatomic.h>` has many macros to built-in functions.
```
#define atomic_thread_fence(order) __c11_atomic_thread_fence(order)
```
and MSVC `<atomic>` has real functions.
and the built-in functions are redefined.

Reviewed By: #libc, aaron.ballman, Mordante

Differential Revision: https://reviews.llvm.org/D130419
2022-07-25 19:00:29 +02:00
Corentin Jabot fa8a1896a7 [Clang] Add missing paper revisions in the release notes [NFC] 2022-07-24 16:24:11 +02:00
Corentin Jabot c68baa73eb [clang] Fix incorrect constant folding of `if consteval`
Fixes https://github.com/llvm/llvm-project/issues/55638.

`if consteval` was evaluated incorrectly when in a
non-constant context that could be constant-folded.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D130437
2022-07-24 16:18:12 +02:00
Corentin Jabot 0ba128f7c8 [Clang] De-deprecate volatile compound operations
As per P2327R1,

|=, &= and ^= are no longer deprecated in all languages mode.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D130421
2022-07-24 16:16:52 +02:00
Corentin Jabot 559f07b872 [Clang] Adjust extension warnings for #warning
The #warning directive is standard in C++2b and C2x,
this adjusts the pedantic and extensions warning accordingly.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D130415
2022-07-23 14:10:11 +02:00
Corentin Jabot aee76cb59c [Clang] Add support for Unicode identifiers (UAX31) in C2x mode.
This implements
N2836 Identifier Syntax using Unicode Standard Annex 31.

The feature was already implemented for C++,
and the semantics are the same.

Unlike C++ there was, afaict, no decision to
backport the feature in older languages mode,
so C17 and earlier are not modified and the
code point tables for these language modes are conserved.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D130416
2022-07-23 14:08:08 +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
Zequan Wu d870a57563 [SemaCXX] Set promotion type for enum if its type is promotable to integer type even if it has no definition.
EnumDecl's promotion type is set either to the parsed type or calculated type
after completing its definition. When it's bool type and has no definition,
its promotion type is bool which is not allowed by clang.

Fixes #56560.

Differential Revision: https://reviews.llvm.org/D130210
2022-07-21 11:23:21 -07:00
serge-sans-paille f764dc99b3 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member

This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-07-18 12:45:52 +02:00
Shafik Yaghmour 80dec2ecff [Clang] Modify CXXMethodDecl::isMoveAssignmentOperator() to look through type sugar
AcceptedPublic

Currently CXXMethodDecl::isMoveAssignmentOperator() does not look though type
sugar and so if the parameter is a type alias it will not be able to detect
that the method is a move assignment operator. This PR fixes that and adds a set
of tests that covers that we correctly detect special member functions when
defaulting or deleting them.

This fixes: https://github.com/llvm/llvm-project/issues/56456

Differential Revision: https://reviews.llvm.org/D129591
2022-07-14 16:09:52 -07:00
Corentin Jabot 6882ca9aff [Clang] Adjust extension warnings for delimited sequences
WG21 approved delimited escape sequences and named escape
sequences.
Adjust the extension warnings accordingly, and update
the release notes.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D129664
2022-07-14 07:50:58 +02:00
Corentin Jabot d4892a168f [Clang] Add a warning on invalid UTF-8 in comments.
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.

Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.

The warning is off by default as its likely to be somewhat disruptive
otherwise.

This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.

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

Differential Revision: https://reviews.llvm.org/D128059
2022-07-13 10:19:26 +02:00
Jonas Devlieghere a262f4dbd7 Revert "[Clang] Add a warning on invalid UTF-8 in comments."
This reverts commit cc309721d2 because it
breaks the following tests on GreenDragon:

  TestDataFormatterObjCCF.py
  TestDataFormatterObjCExpr.py
  TestDataFormatterObjCKVO.py
  TestDataFormatterObjCNSBundle.py
  TestDataFormatterObjCNSData.py
  TestDataFormatterObjCNSError.py
  TestDataFormatterObjCNSNumber.py
  TestDataFormatterObjCNSURL.py
  TestDataFormatterObjCPlain.py
  TestDataFormatterObjNSException.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45288/
2022-07-12 15:22:29 -07:00
Roy Jacobson 0b89d1d59f [Sema] Add deprecation warnings for some compiler provided __has_* type traits
Some compiler provided type traits like __has_trivial_constructor have been documented
as deprecated for quite some time.
Still, some people apparently still use them, even though mixing them with concepts
and with deleted functions leads to weird results. There's also disagreement about some
edge cases between GCC (which Clang claims to follow) and MSVC.

This patch adds deprecation warnings for the usage of those builtins, except for __has_trivial_destructor
which doesn't have a GCC alternative.

I made the warning on by default, so I had to silence it for some tests but it's not too many.

Some (decade old) history of issues with those builtins:
https://github.com/llvm/llvm-project/issues/18187
https://github.com/llvm/llvm-project/issues/18559
https://github.com/llvm/llvm-project/issues/22161
https://github.com/llvm/llvm-project/issues/33063

The abseil usage of them that triggered me to add this warning:
https://github.com/abseil/abseil-cpp/issues/1201

Weird interaction of those builtins with C++20's conditionally trivial special member functions:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106085

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

Differential Revision: https://reviews.llvm.org/D129170
2022-07-12 19:24:17 +03:00
Nick Desaulniers 2240d72f15 [X86] initial -mfunction-return=thunk-extern support
Adds support for:
* `-mfunction-return=<value>` command line flag, and
* `__attribute__((function_return("<value>")))` function attribute

Where the supported <value>s are:
* keep (disable)
* thunk-extern (enable)

thunk-extern enables clang to change ret instructions into jmps to an
external symbol named __x86_return_thunk, implemented as a new
MachineFunctionPass named "x86-return-thunks", keyed off the new IR
attribute fn_ret_thunk_extern.

The symbol __x86_return_thunk is expected to be provided by the runtime
the compiled code is linked against and is not defined by the compiler.
Enabling this option alone doesn't provide mitigations without
corresponding definitions of __x86_return_thunk!

This new MachineFunctionPass is very similar to "x86-lvi-ret".

The <value>s "thunk" and "thunk-inline" are currently unsupported. It's
not clear yet that they are necessary: whether the thunk pattern they
would emit is beneficial or used anywhere.

Should the <value>s "thunk" and "thunk-inline" become necessary,
x86-return-thunks could probably be merged into x86-retpoline-thunks
which has pre-existing machinery for emitting thunks (which could be
used to implement the <value> "thunk").

Has been found to build+boot with corresponding Linux
kernel patches. This helps the Linux kernel mitigate RETBLEED.
* CVE-2022-23816
* CVE-2022-28693
* CVE-2022-29901

See also:
* "RETBLEED: Arbitrary Speculative Code Execution with Return
Instructions."
* AMD SECURITY NOTICE AMD-SN-1037: AMD CPU Branch Type Confusion
* TECHNICAL GUIDANCE FOR MITIGATING BRANCH TYPE CONFUSION REVISION 1.0
  2022-07-12
* Return Stack Buffer Underflow / Return Stack Buffer Underflow /
  CVE-2022-29901, CVE-2022-28693 / INTEL-SA-00702

SystemZ may eventually want to support "thunk-extern" and "thunk"; both
options are used by the Linux kernel's CONFIG_EXPOLINE.

This functionality has been available in GCC since the 8.1 release, and
was backported to the 7.3 release.

Many thanks for folks that provided discrete review off list due to the
embargoed nature of this hardware vulnerability. Many Bothans died to
bring us this information.

Link: https://www.youtube.com/watch?v=IF6HbCKQHK8
Link: https://github.com/llvm/llvm-project/issues/54404
Link: https://gcc.gnu.org/legacy-ml/gcc-patches/2018-01/msg01197.html
Link: https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/advisory-guidance/return-stack-buffer-underflow.html
Link: https://arstechnica.com/information-technology/2022/07/intel-and-amd-cpus-vulnerable-to-a-new-speculative-execution-attack/?comments=1
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ce114c866860aa9eae3f50974efc68241186ba60
Link: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00702.html
Link: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00707.html

Reviewed By: aaron.ballman, craig.topper

Differential Revision: https://reviews.llvm.org/D129572
2022-07-12 09:17:54 -07:00
Chuanqi Xu 4b95a5a772 [Modules] Add ODR Check for concepts
Closing https://github.com/llvm/llvm-project/issues/56310

Previously we don't check the contents of concept so it might merge
inconsistent results.

Important Note: this patch might break existing code but the behavior
might be right.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D129104
2022-07-12 23:45:53 +08:00
Corentin Jabot cc309721d2 [Clang] Add a warning on invalid UTF-8 in comments.
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.

Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.

The warning is off by default as its likely to be somewhat disruptive
otherwise.

This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.

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

Differential Revision: https://reviews.llvm.org/D128059
2022-07-12 14:34:30 +02:00
Aaron Ballman 3cfa32a71e Undeprecate ATOMIC_FLAG_INIT in C++
C++20 deprecated ATOMIC_FLAG_INIT thinking it was deprecated in C when it
wasn't. It is expected to be undeprecated in C++23 as part of LWG3659
(https://wg21.link/LWG3659), which is currently Tentatively Ready.

This handles the case where the user includes <stdatomic.h> in C++ code in a
freestanding compile mode. The corollary libc++ changes are in
1544d1f9fd.
2022-07-12 06:48:31 -04:00
Xiang1 Zhang a45dd3d814 [X86] Support -mstack-protector-guard-symbol
Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D129346
2022-07-12 10:17:00 +08:00
Xiang1 Zhang 643786213b Revert "[X86] Support -mstack-protector-guard-symbol"
This reverts commit efbaad1c4a.
due to miss adding review info.
2022-07-12 10:14:32 +08:00
Xiang1 Zhang efbaad1c4a [X86] Support -mstack-protector-guard-symbol 2022-07-12 10:13:48 +08:00
serge-sans-paille da6a14b91a [clang] Enforce instantiation of constexpr template functions during non-constexpr evaluation
Otherwise these functions are not instantiated and we end up with an undefined
symbol.

Fix #55560

Differential Revision: https://reviews.llvm.org/D128119
2022-07-10 08:40:03 +02:00
Corentin Jabot 50416e5454 Revert "[Clang] Add a warning on invalid UTF-8 in comments."
It is probable thart this change crashes on the powerpc bots.

This reverts commit 355532a149.
2022-07-09 17:18:35 +02:00
Corentin Jabot 355532a149 [Clang] Add a warning on invalid UTF-8 in comments.
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.

Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.

The warning is off by default as its likely to be somewhat disruptive
otherwise.

This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.

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

Differential Revision: https://reviews.llvm.org/D128059
2022-07-09 11:26:45 +02:00
Nathan James 54f57d3847
[clang] Add a fixit for warn-self-assign if LHS is a field with the same name as parameter on RHS
Add a fix-it for the common case of setters/constructors using parameters with the same name as fields
```lang=c++
struct A{
  int X;
  A(int X) { /*this->*/X = X; }
  void setX(int X) { /*this->*/X = X;
};
```

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D129202
2022-07-09 08:28:07 +01:00
serge-sans-paille cc5b77273a [clang] Introduce -Warray-parameter
This warning exist in GCC[0] and warns about re-declarations of functions
involving arguments of array or pointer types of inconsistent kinds or forms.

This is not the exact same implementation as GCC's : there's no warning level
and that flag has no effect on -Warray-bounds.

[0] https://gcc.gnu.org/onlinedocs/gcc-12.1.0/gcc/Warning-Options.html#index-Wno-array-parameter

Differential Revision: https://reviews.llvm.org/D128449
2022-07-08 22:36:05 +02:00
tlattner eb1ffd817c Update references to Discourse instead of the mailing lists.
Update the references to the old Mailman mailing lists to point to Discourse forums.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D128766
2022-07-08 11:16:47 -07:00
Peter Waller 2db2a4e112 [doc][ReleaseNotes] Document AArch64 SVE ABI fix from D127209
D127209 fixed LLVM to bring it in line with the AAPCS. The fix affects
functions where the first SVE parameter appears in the 9th or later
arguments, and the function does not return an SVE type.

Differential Revision: https://reviews.llvm.org/D129135
2022-07-07 10:55:40 +00:00
Nico Weber e9fe20dab3 Revert "[Clang] Add a warning on invalid UTF-8 in comments."
This reverts commit 4174f0ca61.

Also revert follow-up "[Clang] Fix invalid utf-8 detection"
This reverts commit bf45e27a67.

The second commit broke tests, see comments on
https://reviews.llvm.org/D129223, and it sounds like the first
commit isn't valid without the second one. So reverting both for now.
2022-07-06 22:51:52 +02:00
Corentin Jabot 4174f0ca61 [Clang] Add a warning on invalid UTF-8 in comments.
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.

Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.

The warning is off by default as its likely to be somewhat disruptive
otherwise.

This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.

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

Differential Revision: https://reviews.llvm.org/D128059
2022-07-06 21:18:29 +02:00
Corentin Jabot fb06dd3e8c Revert "[Clang] Add a warning on invalid UTF-8 in comments."
Reverting while I investigate build failures

This reverts commit e3dc56805f.
2022-07-06 19:45:12 +02:00
Corentin Jabot e3dc56805f [Clang] Add a warning on invalid UTF-8 in comments.
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.

Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.

The warning is off by default as its likely to be somewhat disruptive
otherwise.

This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.

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

Differential Revision: https://reviews.llvm.org/D128059
2022-07-06 17:59:44 +02:00
Paul Robinson 08e4fe6c61 [X86] Add RDPRU instruction
Add support for the RDPRU instruction on Zen2 processors.

User-facing features:

- Clang option -m[no-]rdpru to enable/disable the feature
- Support is implicit for znver2/znver3 processors
- Preprocessor symbol __RDPRU__ to indicate support
- Header rdpruintrin.h to define intrinsics
- "rdpru" mnemonic supported for assembler code

Internal features:

- Clang builtin __builtin_ia32_rdpru
- IR intrinsic @llvm.x86.rdpru

Differential Revision: https://reviews.llvm.org/D128934
2022-07-06 07:17:47 -07:00
Félix Cloutier 92edd74b37 Allow non-variadic functions to be attributed with `__attribute__((format))`
Clang only allows you to use __attribute__((format)) on variadic functions. There are legit use cases for __attribute__((format)) on non-variadic functions, such as:

(1) variadic templates

```c++
template<typename… Args>
void print(const char *fmt, Args… &&args) __attribute__((format(1, 2))); // error: format attribute requires variadic function
```

(2) functions which take fixed arguments and a custom format:

```c++
void print_number_string(const char *fmt, unsigned number, const char *string) __attribute__((format(1, 2)));
// ^error: format attribute requires variadic function

void foo(void) {
    print_number_string(“%08x %s\n”, 0xdeadbeef, “hello”);
    print_number_string(“%d %s”, 0xcafebabe, “bar”);
}
```

This change allows Clang users to attach __attribute__((format)) to non-variadic functions, including functions with C++ variadic templates. It replaces the error with a GCC compatibility warning and improves the type checker to ensure that received arrays are treated like pointers (this is a possibility in C++ since references to template types can bind to arrays).

Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D112579
rdar://84629099
2022-07-05 17:26:11 -07:00
Tobias Hieta e6ff553979 [clang-extdef-mapping] Directly process .ast files
When doing CTU analysis setup you pre-compile .cpp to .ast and then
you run clang-extdef-mapping on the .cpp file as well. This is a
pretty slow process since we have to recompile the file each time.

With this patch you can now run clang-extdef-mapping directly on
the .ast file. That saves a lot of time.

I tried this on llvm/lib/AsmParser/Parser.cpp and running
extdef-mapping on the .cpp file took 5.4s on my machine.

While running it on the .ast file it took 2s.

This can save a lot of time for the setup phase of CTU analysis.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D128704
2022-07-05 13:45:52 +02:00
Archibald Elliott 1666f09933 [ARM] Add Support for Cortex-M85
This patch adds support for Arm's Cortex-M85 CPU. The Cortex-M85 CPU is
an Arm v8.1m Mainline CPU, with optional support for MVE and PACBTI,
both of which are enabled by default.

Parts have been coauthored by by Mark Murray, Alexandros Lamprineas and
David Green.

Differential Revision: https://reviews.llvm.org/D128415
2022-07-05 10:43:31 +01:00