The sampler handling logic in SemaInit.cpp would inadvertently treat
parentheses around sampler arguments as an implicit cast, leading to
an unreachable "can't implicitly cast lvalue to rvalue with
this cast kind". Fix by ignoring parentheses once we are in the
sampler initializer case.
Differential Revision: https://reviews.llvm.org/D66080
llvm-svn: 368561
The default behavior of Clang's indirect function call checker will replace
the address of each CFI-checked function in the output file's symbol table
with the address of a jump table entry which will pass CFI checks. We refer
to this as making the jump table `canonical`. This property allows code that
was not compiled with ``-fsanitize=cfi-icall`` to take a CFI-valid address
of a function, but it comes with a couple of caveats that are especially
relevant for users of cross-DSO CFI:
- There is a performance and code size overhead associated with each
exported function, because each such function must have an associated
jump table entry, which must be emitted even in the common case where the
function is never address-taken anywhere in the program, and must be used
even for direct calls between DSOs, in addition to the PLT overhead.
- There is no good way to take a CFI-valid address of a function written in
assembly or a language not supported by Clang. The reason is that the code
generator would need to insert a jump table in order to form a CFI-valid
address for assembly functions, but there is no way in general for the
code generator to determine the language of the function. This may be
possible with LTO in the intra-DSO case, but in the cross-DSO case the only
information available is the function declaration. One possible solution
is to add a C wrapper for each assembly function, but these wrappers can
present a significant maintenance burden for heavy users of assembly in
addition to adding runtime overhead.
For these reasons, we provide the option of making the jump table non-canonical
with the flag ``-fno-sanitize-cfi-canonical-jump-tables``. When the jump
table is made non-canonical, symbol table entries point directly to the
function body. Any instances of a function's address being taken in C will
be replaced with a jump table address.
This scheme does have its own caveats, however. It does end up breaking
function address equality more aggressively than the default behavior,
especially in cross-DSO mode which normally preserves function address
equality entirely.
Furthermore, it is occasionally necessary for code not compiled with
``-fsanitize=cfi-icall`` to take a function address that is valid
for CFI. For example, this is necessary when a function's address
is taken by assembly code and then called by CFI-checking C code. The
``__attribute__((cfi_jump_table_canonical))`` attribute may be used to make
the jump table entry of a specific function canonical so that the external
code will end up taking a address for the function that will pass CFI checks.
Fixes PR41972.
Differential Revision: https://reviews.llvm.org/D65629
llvm-svn: 368495
This patch adds the SVE built-in types defined by the Procedure Call
Standard for the Arm Architecture:
https://developer.arm.com/docs/100986/0000
It handles the types in all relevant places that deal with built-in types.
At the moment, some of these places bail out with an error, including:
(1) trying to generate LLVM IR for the types
(2) trying to generate debug info for the types
(3) trying to mangle the types using the Microsoft C++ ABI
(4) trying to @encode the types in Objective C
(1) and (2) are fixed by follow-on patches but (unlike this patch)
they deal mostly with target-specific LLVM details, so seemed like
a logically separate change. There is currently no spec for (3) and
(4), so reporting an error seems like the correct behaviour for now.
The intention is that the types will become sizeless types:
http://lists.llvm.org/pipermail/cfe-dev/2019-June/062523.html
The main purpose of the sizeless type extension is to diagnose
impossible or dangerous uses of the types, such as any that would
require sizeof to have a meaningful defined value.
Until then, the patch sets the alignments of the types to the values
specified in the link above. It also sets the sizes of the types to
zero, which is chosen to be consistently wrong and shouldn't affect
correctly-written code (i.e. code that would compile even with the
sizeless type extension).
The patch adds the common subset of functionality needed to test the
sizeless type extension on the one hand and to provide SVE intrinsic
functions on the other. After this patch, the two pieces of work are
essentially independent.
The patch is based on one by Graham Hunter:
https://reviews.llvm.org/D59245
Differential Revision: https://reviews.llvm.org/D62960
llvm-svn: 368413
Summary:
Added support for basic analysis of the linear variables and linear step
expression. Linear loop iteration variables must be excluded from this
analysis, only non-loop iteration variables must be analyzed.
Reviewers: NoQ
Subscribers: guansong, cfe-commits, caomhin, kkwli0
Tags: #clang
Differential Revision: https://reviews.llvm.org/D65461
llvm-svn: 368295
Fix -Wpessimizing-move and -Wredundant-move when warning on initializer lists.
The new fix-it hints for removing the std::move call will now also suggest
removing the braces for the initializer list so that the resulting code will
still be compilable.
This fixes PR42832
llvm-svn: 368237
Summary:
Hard code gsl::Owner/gsl::Pointer for std types. The paper mentions
some types explicitly. Generally, all containers and their iterators are
covered. For iterators, we cover both the case that they are defined
as an nested class or as an typedef/using. I have started to test this
implementation against some real standard library implementations, namely
libc++ 7.1.0, libc++ 8.0.1rc2, libstdc++ 4.6.4, libstdc++ 4.8.5,
libstdc++ 4.9.4, libstdc++ 5.4.0, libstdc++ 6.5.0, libstdc++ 7.3.0,
libstdc++ 8.3.0 and libstdc++ 9.1.0.
The tests are currently here
https://github.com/mgehre/llvm-project/blob/lifetime-ci/lifetime-attr-test.shhttps://github.com/mgehre/llvm-project/blob/lifetime-ci/lifetime-attr-test.cpp
I think due to their dependency on a standard library, they are not a good fit
for clang/test/. Where else could I put them?
Reviewers: gribozavr, xazax.hun
Subscribers: rnkovacs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64448
llvm-svn: 368147
Summary:
An inline asm call may result in an immediate input value after inlining.
Therefore, don't emit a diagnostic here if the input isn't an immediate.
Reviewers: joerg, eli.friedman, rsmith
Subscribers: asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, s.egerton, krytarowski, mgorny, riccibruno, eraman, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D60943
llvm-svn: 368104
This patch extends some existing warnings to utilize the knowledge about the gsl::Pointer and gsl::Owner attributes.
Differential Revision: https://reviews.llvm.org/D64256
llvm-svn: 368072
This patch adds a warning that diagnoses comparisons of pointers to
'\0'. This is often indicative of a bug (e.g. the user might've
forgotten to dereference the pointer).
Patch by Elaina Guan!
Differential Revision: https://reviews.llvm.org/D65595
llvm-svn: 367940
This is similar to r245139, but that only addressed dllexported classes.
It was still possible to run into the same problem with dllexported
members in an otherwise normal class (see bug). This uses the same
strategy to fix: delay defining the method until the whole class has
been parsed.
(The easiest way to see the ordering problem is in
Parser::ParseCXXMemberSpecification(): it calls
ParseLexedMemberInitializers() *after* ActOnFinishCXXMemberDecls(),
which was trying to define the dllexport method. Now we delay it to
ActOnFinishCXXNonNestedClass() which is called after both of those.)
Differential revision: https://reviews.llvm.org/D65511
llvm-svn: 367520
Issue an warning when the code tries to do an implicit int -> float
conversion, where the float type ha a narrower significant than the
float type.
The new warning is controlled by flag -Wimplicit-int-float-conversion,
under -Wimplicit-float-conversion and -Wconversion. It is also silenced
when c++11 narrowing warning is issued.
Differential Revision: https://reviews.llvm.org/D64666
llvm-svn: 367497
If we detect a built-in declaration for which we cannot derive a type
matching the pattern in the Builtins.def file, we currently emit a
warning that the respective header is needed. However, this is not
necessarily the behavior we want as it has no connection to the location
of the declaration (which can actually be in the header in question).
Instead, this warning is generated
- if we could not build the type for the pattern on file (for some
reason). Here we should make the reason explicit. The actual problem
is otherwise circumvented as the warning is misleading, see [0] for
an example.
- if we could not build the type for the pattern because we do not
have a type on record, possible since D55483, we should not emit any
warning. See [1] for a legitimate problem.
This patch address both cases. For the "setjmp" family a new warning is
introduced and for built-ins without type on record, so far
"pthread_create", we do not emit the warning anymore.
Also see: PR40692
[0] https://lkml.org/lkml/2019/1/11/718
[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=235583
Differential Revision: https://reviews.llvm.org/D58091
llvm-svn: 367387
We were previously just using a specialization in the class template instead of
creating a new specialization in the class instantiation.
Fixes llvm.org/PR42779.
Differential revision: https://reviews.llvm.org/D65359
llvm-svn: 367367
As discussed in D65249, don't use AlignedCharArray or std::aligned_storage. Just use alignas(X) char Buf[Size];. This will allow me to remove AlignedCharArray entirely, and works on the current minimum version of Visual Studio.
llvm-svn: 367274
check the formal rules rather than seeing if the normal checks produce a
diagnostic.
This fixes the handling of C++2a extensions in lambdas in C++17 mode,
as well as some corner cases in earlier language modes where we issue
diagnostics for things other than not satisfying the formal constexpr
requirements.
llvm-svn: 367254
Factor out some of the renames from D63434 and D63442, and generate
half type convert_ builtins.
Patch by Pierre Gondois and Sven van Haastregt.
llvm-svn: 367229
This reverts commit r365985.
Prior to r365985, clang used to mark C union fields that have
non-trivial ObjC ownership qualifiers as unavailable if the union was
declared in a system header. r365985 stopped doing so, which caused the
swift compiler to crash when it tried to import a non-trivial union.
I have a patch that fixes the crash (https://reviews.llvm.org/D65256),
but I'm temporarily reverting the original patch until we can decide on
whether it's taking the right approach.
llvm-svn: 367076
This CL adds an optional warning to diagnose uses of the
`__builtin_alloca` family of functions. The use of these functions is
discouraged by many, so it seems like a good idea to allow clang to warn
about it.
Patch by Elaina Guan!
Differential Revision: https://reviews.llvm.org/D64883
llvm-svn: 367067
Summary:
This is the first part of work announced in
"[RFC] Adding lifetime analysis to clang" [0],
i.e. the addition of the [[gsl::Owner(T)]] and
[[gsl::Pointer(T)]] attributes, which
will enable user-defined types to participate in
the lifetime analysis (which will be part of the
next PR).
The type `T` here is called "DerefType" in the paper,
and denotes the type that an Owner owns and a Pointer
points to. E.g. `std::vector<int>` should be annotated
with `[[gsl::Owner(int)]]` and
a `std::vector<int>::iterator` with `[[gsl::Pointer(int)]]`.
[0] http://lists.llvm.org/pipermail/cfe-dev/2018-November/060355.html
Reviewers: gribozavr
Subscribers: xazax.hun, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63954
llvm-svn: 367040
As passed in the Cologne meeting and treated by Core as a DR,
[[nodiscard]] was applied to constructors so that they can be diagnosed
in cases where the user forgets a variable name for a type.
The intent is to enable the library to start using this on the
constructors of scope_guard/lock_guard.
Differential Revision: https://reviews.llvm.org/D64914
llvm-svn: 367027
This adds a new vectorize predication loop hint:
#pragma clang loop vectorize_predicate(enable)
that can be used to indicate to the vectoriser that all (load/store)
instructions should be predicated (masked). This allows, for example, folding
of the remainder loop into the main loop.
This patch will be followed up with D64916 and D65197. The former is a
refactoring in the loopvectorizer and the groundwork to make tail loop folding
a more general concept, and in the latter the actual tail loop folding
transformation will be implemented.
Differential Revision: https://reviews.llvm.org/D64744
llvm-svn: 366989
This reverts commit r366972 which broke the following tests:
Clang :: CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
Clang :: CXX/dcl.decl/dcl.init/dcl.init.list/p7-cxx11-nowarn.cpp
llvm-svn: 366979
Issue an warning when the code tries to do an implicit int -> float
conversion, where the float type ha a narrower significant than the
float type.
The new warning is controlled by flag -Wimplicit-int-float-conversion,
under -Wimplicit-float-conversion and -Wconversion.
Differential Revision: https://reviews.llvm.org/D64666
llvm-svn: 366972
If the threadprivate variable is used in the copyin clause on inner
parallel directive with TLS support, we capture this variable in all
outer OpenMP scopes. It leads to the fact that in all scopes we're
working with the original variable, not the threadprivate copies.
llvm-svn: 366483
variables.
Loop control variables are private in loop-based constructs and we shall
take this into account when generate the code for inner constructs.
Currently, those variables are reported as shared in many cases. Moved
the analysis of the data-sharing attributes of the loop control variable
to an early semantic stage to correctly handle their attributes.
llvm-svn: 366474
Reason: this commit causes crashes in the clang compiler when building
LLVM Support with libc++, see https://bugs.llvm.org/show_bug.cgi?id=42665
for details.
llvm-svn: 366429
Summary:
This patch does mainly three things:
1. It fixes a false positive error detection in Sema that is similar to
D62156. The error happens when explicitly calling an overloaded
destructor for different address spaces.
2. It selects the correct destructor when multiple overloads for
address spaces are available.
3. It inserts the expected address space cast when invoking a
destructor, if needed, and therefore fixes a crash due to the unmet
assertion in llvm::CastInst::Create.
The following is a reproducer of the three issues:
struct MyType {
~MyType() {}
~MyType() __constant {}
};
__constant MyType myGlobal{};
kernel void foo() {
myGlobal.~MyType(); // 1 and 2.
// 1. error: cannot initialize object parameter of type
// '__generic MyType' with an expression of type '__constant MyType'
// 2. error: no matching member function for call to '~MyType'
}
kernel void bar() {
// 3. The implicit call to the destructor crashes due to:
// Assertion `castIsValid(op, S, Ty) && "Invalid cast!"' failed.
// in llvm::CastInst::Create.
MyType myLocal;
}
The added test depends on D62413 and covers a few more things than the
above reproducer.
Subscribers: yaxunl, Anastasia, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64569
llvm-svn: 366422
If dependent types appear in pointers or references we allow addr
space deduction because the addr space in template argument will
belong to the pointee and not the pointer or reference itself.
We also don't diagnose addr space on a function return type after
template instantiation. If any addr space for the return type was
provided on a template parameter this will be diagnosed during the
parsing of template definition.
Differential Revision: https://reviews.llvm.org/D62584
llvm-svn: 366417
Summary:
The problem is the default LoadExternal with no completer, which happens when
loading global results.
Reviewers: ilya-biryukov, nik
Subscribers: arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64864
llvm-svn: 366409
As discussed in D64780 the wording of this warning message is being
changed to say 'is not supported' instead of 'ignored', and the
diag ID itself is being changed to warn_cconv_not_supported.
llvm-svn: 366368
checkDecl is only valid for VarDecls or FieldDecls, since getCanonicalDecl
expects only these. Prevent other Decl kinds (such as CXXMethodDecls and
EnumConstantDecls) from entering and asserting.
Differential Revision: https://reviews.llvm.org/D64842
llvm-svn: 366336
Summary:
Simplify code a bit and add assertion to address post-landing comments
from D64083.
Subscribers: yaxunl, Anastasia, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64804
llvm-svn: 366306
Summary:
This case is particularly important for clangd, as it is triggered after
inserting the snippet for variadic functions.
Reviewers: kadircet, ilya-biryukov
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64677
llvm-svn: 366200
Since pointee doesn't require context sensitive addr space deduction
it's easier to handle pointee of dependent types during templ
instantiation.
Differential Revision: https://reviews.llvm.org/D64400
llvm-svn: 366063
non-trivial C union types
This patch diagnoses uses of non-trivial C unions and structs/unions
containing non-trivial C unions in the following contexts, which require
default-initialization, destruction, or copying of the union objects,
instead of disallowing fields of non-trivial types in C unions, which is
what we currently do:
- function parameters.
- function returns.
- assignments.
- compound literals.
- block captures except capturing of `__block` variables by non-escaping
blocks.
- local and global variable definitions.
- lvalue-to-rvalue conversions of volatile types.
See the discussion in https://reviews.llvm.org/D62988 for more background.
rdar://problem/50679094
Differential Revision: https://reviews.llvm.org/D63753
llvm-svn: 365985
This patch series adds support for the next-generation arch13
CPU architecture to the SystemZ backend.
This includes:
- Basic support for the new processor and its features.
- Support for low-level builtins mapped to new LLVM intrinsics.
- New high-level intrinsics in vecintrin.h.
- Indicate support by defining __VEC__ == 10303.
Note: No currently available Z system supports the arch13
architecture. Once new systems become available, the
official system name will be added as supported -march name.
llvm-svn: 365933
Fixed the processing of the unsupported VLAs in the reduction clauses.
Used targetDiag if the diagnostics can be delayed and emit it
immediately if the target does not support VLAs and we're parsing target
directive with the reduction clauses.
llvm-svn: 365821
I would like to add some pragma handling here, but couldn't resist a little NFC
and tidy up first.
Differential Revision: https://reviews.llvm.org/D64471
llvm-svn: 365629
The CCCR_Ignore action is only used for Microsoft calling conventions,
mainly because MSVC does not warn when a calling convention would be
ignored by the current target. This behavior is actually somewhat
important, since windows.h uses WINAPI (which expands to __stdcall)
widely. This distinction didn't matter much before the introduction of
__vectorcall to x64 and the ability to make that the default calling
convention with /Gv. Now, we can't just ignore __stdcall for x64, we
have to treat it as an explicit __cdecl annotation.
Fixes PR42531
llvm-svn: 365579
Summary:
This patch ensures that the following code is compiled identically with
-cl-std=CL2.0 and -fblocks -cl-std=c++.
kernel void test(void) {
void (^const block_A)(void) = ^{
return;
};
}
A new test is not added because cl20-device-side-enqueue.cl will cover
this once blocks are further improved for C++ for OpenCL.
The changes to Sema::PerformImplicitConversion are based on
the parts of Sema::CheckAssignmentConstraints on block pointer
conversions.
Reviewers: rjmccall, Anastasia
Subscribers: yaxunl, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64083
llvm-svn: 365500
This patch ensures built-in functions are rewritten using the proper
parent declaration.
Existing tests are modified to run in C++ mode to ensure the
functionality works also with C++ for OpenCL while not increasing the
testing runtime.
llvm-svn: 365499
Ignore trailing NullStmts in compound expressions when determining the result type and value. This is to match the GCC behavior which ignores semicolons at the end of compound expressions.
Patch by Dominic Ferreira.
llvm-svn: 365498
For background of BPF CO-RE project, please refer to
http://vger.kernel.org/bpfconf2019.html
In summary, BPF CO-RE intends to compile bpf programs
adjustable on struct/union layout change so the same
program can run on multiple kernels with adjustment
before loading based on native kernel structures.
In order to do this, we need keep track of GEP(getelementptr)
instruction base and result debuginfo types, so we
can adjust on the host based on kernel BTF info.
Capturing such information as an IR optimization is hard
as various optimization may have tweaked GEP and also
union is replaced by structure it is impossible to track
fieldindex for union member accesses.
Three intrinsic functions, preserve_{array,union,struct}_access_index,
are introducted.
addr = preserve_array_access_index(base, index, dimension)
addr = preserve_union_access_index(base, di_index)
addr = preserve_struct_access_index(base, gep_index, di_index)
here,
base: the base pointer for the array/union/struct access.
index: the last access index for array, the same for IR/DebugInfo layout.
dimension: the array dimension.
gep_index: the access index based on IR layout.
di_index: the access index based on user/debuginfo types.
If using these intrinsics blindly, i.e., transforming all GEPs
to these intrinsics and later on reducing them to GEPs, we have
seen up to 7% more instructions generated. To avoid such an overhead,
a clang builtin is proposed:
base = __builtin_preserve_access_index(base)
such that user wraps to-be-relocated GEPs in this builtin
and preserve_*_access_index intrinsics only apply to
those GEPs. Such a buyin will prevent performance degradation
if people do not use CO-RE, even for programs which use
bpf_probe_read().
For example, for the following example,
$ cat test.c
struct sk_buff {
int i;
int b1:1;
int b2:2;
union {
struct {
int o1;
int o2;
} o;
struct {
char flags;
char dev_id;
} dev;
int netid;
} u[10];
};
static int (*bpf_probe_read)(void *dst, int size, const void *unsafe_ptr)
= (void *) 4;
#define _(x) (__builtin_preserve_access_index(x))
int bpf_prog(struct sk_buff *ctx) {
char dev_id;
bpf_probe_read(&dev_id, sizeof(char), _(&ctx->u[5].dev.dev_id));
return dev_id;
}
$ clang -target bpf -O2 -g -emit-llvm -S -mllvm -print-before-all \
test.c >& log
The generated IR looks like below:
...
define dso_local i32 @bpf_prog(%struct.sk_buff*) #0 !dbg !15 {
%2 = alloca %struct.sk_buff*, align 8
%3 = alloca i8, align 1
store %struct.sk_buff* %0, %struct.sk_buff** %2, align 8, !tbaa !45
call void @llvm.dbg.declare(metadata %struct.sk_buff** %2, metadata !43, metadata !DIExpression()), !dbg !49
call void @llvm.lifetime.start.p0i8(i64 1, i8* %3) #4, !dbg !50
call void @llvm.dbg.declare(metadata i8* %3, metadata !44, metadata !DIExpression()), !dbg !51
%4 = load i32 (i8*, i32, i8*)*, i32 (i8*, i32, i8*)** @bpf_probe_read, align 8, !dbg !52, !tbaa !45
%5 = load %struct.sk_buff*, %struct.sk_buff** %2, align 8, !dbg !53, !tbaa !45
%6 = call [10 x %union.anon]* @llvm.preserve.struct.access.index.p0a10s_union.anons.p0s_struct.sk_buffs(
%struct.sk_buff* %5, i32 2, i32 3), !dbg !53, !llvm.preserve.access.index !19
%7 = call %union.anon* @llvm.preserve.array.access.index.p0s_union.anons.p0a10s_union.anons(
[10 x %union.anon]* %6, i32 1, i32 5), !dbg !53
%8 = call %union.anon* @llvm.preserve.union.access.index.p0s_union.anons.p0s_union.anons(
%union.anon* %7, i32 1), !dbg !53, !llvm.preserve.access.index !26
%9 = bitcast %union.anon* %8 to %struct.anon.0*, !dbg !53
%10 = call i8* @llvm.preserve.struct.access.index.p0i8.p0s_struct.anon.0s(
%struct.anon.0* %9, i32 1, i32 1), !dbg !53, !llvm.preserve.access.index !34
%11 = call i32 %4(i8* %3, i32 1, i8* %10), !dbg !52
%12 = load i8, i8* %3, align 1, !dbg !54, !tbaa !55
%13 = sext i8 %12 to i32, !dbg !54
call void @llvm.lifetime.end.p0i8(i64 1, i8* %3) #4, !dbg !56
ret i32 %13, !dbg !57
}
!19 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "sk_buff", file: !3, line: 1, size: 704, elements: !20)
!26 = distinct !DICompositeType(tag: DW_TAG_union_type, scope: !19, file: !3, line: 5, size: 64, elements: !27)
!34 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !26, file: !3, line: 10, size: 16, elements: !35)
Note that @llvm.preserve.{struct,union}.access.index calls have metadata llvm.preserve.access.index
attached to instructions to provide struct/union debuginfo type information.
For &ctx->u[5].dev.dev_id,
. The "%6 = ..." represents struct member "u" with index 2 for IR layout and index 3 for DI layout.
. The "%7 = ..." represents array subscript "5".
. The "%8 = ..." represents union member "dev" with index 1 for DI layout.
. The "%10 = ..." represents struct member "dev_id" with index 1 for both IR and DI layout.
Basically, traversing the use-def chain recursively for the 3rd argument of bpf_probe_read() and
examining all preserve_*_access_index calls, the debuginfo struct/union/array access index
can be achieved.
The intrinsics also contain enough information to regenerate codes for IR layout.
For array and structure intrinsics, the proper GEP can be constructed.
For union intrinsics, replacing all uses of "addr" with "base" should be enough.
Signed-off-by: Yonghong Song <yhs@fb.com>
Differential Revision: https://reviews.llvm.org/D61809
llvm-svn: 365438
For background of BPF CO-RE project, please refer to
http://vger.kernel.org/bpfconf2019.html
In summary, BPF CO-RE intends to compile bpf programs
adjustable on struct/union layout change so the same
program can run on multiple kernels with adjustment
before loading based on native kernel structures.
In order to do this, we need keep track of GEP(getelementptr)
instruction base and result debuginfo types, so we
can adjust on the host based on kernel BTF info.
Capturing such information as an IR optimization is hard
as various optimization may have tweaked GEP and also
union is replaced by structure it is impossible to track
fieldindex for union member accesses.
Three intrinsic functions, preserve_{array,union,struct}_access_index,
are introducted.
addr = preserve_array_access_index(base, index, dimension)
addr = preserve_union_access_index(base, di_index)
addr = preserve_struct_access_index(base, gep_index, di_index)
here,
base: the base pointer for the array/union/struct access.
index: the last access index for array, the same for IR/DebugInfo layout.
dimension: the array dimension.
gep_index: the access index based on IR layout.
di_index: the access index based on user/debuginfo types.
If using these intrinsics blindly, i.e., transforming all GEPs
to these intrinsics and later on reducing them to GEPs, we have
seen up to 7% more instructions generated. To avoid such an overhead,
a clang builtin is proposed:
base = __builtin_preserve_access_index(base)
such that user wraps to-be-relocated GEPs in this builtin
and preserve_*_access_index intrinsics only apply to
those GEPs. Such a buyin will prevent performance degradation
if people do not use CO-RE, even for programs which use
bpf_probe_read().
For example, for the following example,
$ cat test.c
struct sk_buff {
int i;
int b1:1;
int b2:2;
union {
struct {
int o1;
int o2;
} o;
struct {
char flags;
char dev_id;
} dev;
int netid;
} u[10];
};
static int (*bpf_probe_read)(void *dst, int size, const void *unsafe_ptr)
= (void *) 4;
#define _(x) (__builtin_preserve_access_index(x))
int bpf_prog(struct sk_buff *ctx) {
char dev_id;
bpf_probe_read(&dev_id, sizeof(char), _(&ctx->u[5].dev.dev_id));
return dev_id;
}
$ clang -target bpf -O2 -g -emit-llvm -S -mllvm -print-before-all \
test.c >& log
The generated IR looks like below:
...
define dso_local i32 @bpf_prog(%struct.sk_buff*) #0 !dbg !15 {
%2 = alloca %struct.sk_buff*, align 8
%3 = alloca i8, align 1
store %struct.sk_buff* %0, %struct.sk_buff** %2, align 8, !tbaa !45
call void @llvm.dbg.declare(metadata %struct.sk_buff** %2, metadata !43, metadata !DIExpression()), !dbg !49
call void @llvm.lifetime.start.p0i8(i64 1, i8* %3) #4, !dbg !50
call void @llvm.dbg.declare(metadata i8* %3, metadata !44, metadata !DIExpression()), !dbg !51
%4 = load i32 (i8*, i32, i8*)*, i32 (i8*, i32, i8*)** @bpf_probe_read, align 8, !dbg !52, !tbaa !45
%5 = load %struct.sk_buff*, %struct.sk_buff** %2, align 8, !dbg !53, !tbaa !45
%6 = call [10 x %union.anon]* @llvm.preserve.struct.access.index.p0a10s_union.anons.p0s_struct.sk_buffs(
%struct.sk_buff* %5, i32 2, i32 3), !dbg !53, !llvm.preserve.access.index !19
%7 = call %union.anon* @llvm.preserve.array.access.index.p0s_union.anons.p0a10s_union.anons(
[10 x %union.anon]* %6, i32 1, i32 5), !dbg !53
%8 = call %union.anon* @llvm.preserve.union.access.index.p0s_union.anons.p0s_union.anons(
%union.anon* %7, i32 1), !dbg !53, !llvm.preserve.access.index !26
%9 = bitcast %union.anon* %8 to %struct.anon.0*, !dbg !53
%10 = call i8* @llvm.preserve.struct.access.index.p0i8.p0s_struct.anon.0s(
%struct.anon.0* %9, i32 1, i32 1), !dbg !53, !llvm.preserve.access.index !34
%11 = call i32 %4(i8* %3, i32 1, i8* %10), !dbg !52
%12 = load i8, i8* %3, align 1, !dbg !54, !tbaa !55
%13 = sext i8 %12 to i32, !dbg !54
call void @llvm.lifetime.end.p0i8(i64 1, i8* %3) #4, !dbg !56
ret i32 %13, !dbg !57
}
!19 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "sk_buff", file: !3, line: 1, size: 704, elements: !20)
!26 = distinct !DICompositeType(tag: DW_TAG_union_type, scope: !19, file: !3, line: 5, size: 64, elements: !27)
!34 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !26, file: !3, line: 10, size: 16, elements: !35)
Note that @llvm.preserve.{struct,union}.access.index calls have metadata llvm.preserve.access.index
attached to instructions to provide struct/union debuginfo type information.
For &ctx->u[5].dev.dev_id,
. The "%6 = ..." represents struct member "u" with index 2 for IR layout and index 3 for DI layout.
. The "%7 = ..." represents array subscript "5".
. The "%8 = ..." represents union member "dev" with index 1 for DI layout.
. The "%10 = ..." represents struct member "dev_id" with index 1 for both IR and DI layout.
Basically, traversing the use-def chain recursively for the 3rd argument of bpf_probe_read() and
examining all preserve_*_access_index calls, the debuginfo struct/union/array access index
can be achieved.
The intrinsics also contain enough information to regenerate codes for IR layout.
For array and structure intrinsics, the proper GEP can be constructed.
For union intrinsics, replacing all uses of "addr" with "base" should be enough.
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 365435
On macOS, BOOL is a typedef for signed char, but it should never hold a value
that isn't 1 or 0. Any code that expects a different value in their BOOL should
be fixed.
rdar://51954400
Differential revision: https://reviews.llvm.org/D63856
llvm-svn: 365408
This is a fix for rG864949 which only disabled default construction and
assignment for lambdas with capture-defaults, where the C++2a draft
disables them for lambdas with any lambda-capture at all.
Patch by Logan Smith!
Differential Revision: https://reviews.llvm.org/D64058
llvm-svn: 365406
This reverts r365382 (git commit 8b1becf2e3)
Appears to regress this semi-reduced fragment of valid code from windows
SDK headers:
#define InterlockedIncrement64 _InterlockedIncrement64
extern "C" __int64 InterlockedIncrement64(__int64 volatile *Addend);
#pragma intrinsic(_InterlockedIncrement64)
unsigned __int64 InterlockedIncrement(unsigned __int64 volatile *Addend) {
return (unsigned __int64)(InterlockedIncrement64)((volatile __int64 *)Addend);
}
Found on a buildbot here, but no mail was sent due to it already being
red:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/48067
llvm-svn: 365393
Summary:
Currently HeaderSearch only looks at SearchDir's passed into it, but in
addition to those paths headers can be relative to including file's directory.
This patch makes sure that is taken into account.
Reviewers: gribozavr
Subscribers: jkorous, arphaman, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63295
llvm-svn: 365005
This commit adds a new builtin, __builtin_bit_cast(T, v), which performs a
bit_cast from a value v to a type T. This expression can be evaluated at
compile time under specific circumstances.
The compile time evaluation currently doesn't support bit-fields, but I'm
planning on fixing this in a follow up (some of the logic for figuring this out
is in CodeGen). I'm also planning follow-ups for supporting some more esoteric
types that the constexpr evaluator supports, as well as extending
__builtin_memcpy constexpr evaluation to use the same infrastructure.
rdar://44987528
Differential revision: https://reviews.llvm.org/D62825
llvm-svn: 364954
Previously, lambda captures were processed in the function called during
capturing the variables. It leads to the recursive functions calls and
may result in the compiler crash.
llvm-svn: 364820
If the variable is used in the OpenMP region implicitly, we need to
check the data-sharing attributes for such variables and generate
implicit clauses for them. Patch improves analysis of such variables for
better handling of data-sharing rules.
llvm-svn: 364683
Fixed handling of the data-sharing attributes for static members when
requesting top most attribute. Previously, it might return the incorrect
attributes for static members if they were overriden in the outer
constructs.
llvm-svn: 364655
According to the OpenMP 5.0 standard, the loop iteration variable in the associated
for-loop of a simd construct with just one associated for-loop may be
listed in a private, lastprivate, or linear clause with a linear-step
that is the increment of the associated for-loop. Also, the loop
teration variables in the associated for-loops of a simd construct with
multiple associated for-loops may be listed in a private or lastprivate
clause.
llvm-svn: 364650
The errors for incorrectly specified data-sharing attributes for simd
constructs must be emitted only for the explicitly provided clauses, not
the predetermined ones.
llvm-svn: 364647
Without an explicit declaration for placement new, clang would reject
uses of placement new with "'default new' is not supported in OpenCL
C++". This may mislead users into thinking that placement new is not
supported, see e.g. PR42060.
Clarify that placement new requires an explicit declaration.
Differential Revision: https://reviews.llvm.org/D63561
llvm-svn: 364423
This patch introduces support of hip_pinned_shadow variable for HIP.
A hip_pinned_shadow variable is a global variable with attribute hip_pinned_shadow.
It has external linkage on device side and has no initializer. It has internal
linkage on host side and has initializer or static constructor. It can be accessed
in both device code and host code.
This allows HIP runtime to implement support of HIP texture reference.
Differential Revision: https://reviews.llvm.org/D62738
llvm-svn: 364381
type-dependent argument packs.
We need to strip off the PackExpansionExpr to get the real (dependent)
type rather than an opaque DependentTy.
llvm-svn: 364165
If the variably modified type is declared outside of the captured region
and then used in the cast expression along with array subscript
expression, the type is not captured and it leads to the compiler crash.
llvm-svn: 364080
Summary:
this patch has multiple small improvements related to the APValue in ConstantExpr.
changes:
- APValue in ConstantExpr are now cleaned up using ASTContext::addDestruction instead of there own system.
- ConstantExprBits Stores the ValueKind of the result beaing stored.
- VerifyIntegerConstantExpression now stores the evaluated value in ConstantExpr.
- the Constant Evaluator uses the stored value of ConstantExpr when available.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63376
llvm-svn: 364011
Summary:
Add support for the C++2a [[no_unique_address]] attribute for targets using the Itanium C++ ABI.
This depends on D63371.
Reviewers: rjmccall, aaron.ballman
Subscribers: dschuff, aheejin, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63451
llvm-svn: 363976
template argument contains a backreference to a dependently-typed
earlier parameter.
In a case like:
template<typename T, T A, decltype(A) = A> struct X {};
template<typename U> auto Y = X<U, 0>();
we previously treated both references to `A` in the third parameter as
being of type `int` when checking the template-id in `Y`. That`s wrong;
the type of `A` in these contexts is the dependent type `U`.
When we encounter a non-type template argument that we can't convert to
the parameter type because of type-dependence, we now insert a dependent
conversion node so that the SubstNonTypeTemplateParmExpr for the
template argument will have the parameter's type rather than whatever
type the argument had.
llvm-svn: 363972
If we construct an object in some arbitrary non-default addr space
it should fail unless either:
- There is an implicit conversion from the address space to default
/generic address space.
- There is a matching ctor qualified with an address space that is
either exactly matching or convertible to the address space of an
object.
Differential Revision: https://reviews.llvm.org/D62156
llvm-svn: 363944
Summary:
I've found that most often the proper way to fix this warning is to add
`static`, because if the code otherwise compiles and links, the function
or variable is apparently not needed outside of the TU.
We can't provide a fix-it hint for variable declarations, because
multiple VarDecls can share the same type, and if we put static in front
of that, we affect all declared variables, some of which might have
previous declarations.
We also provide no fix-it hint for the rare case of an `extern` function
definition, because that would require removing `extern` and I have no
idea how to get the source location of the storage class specifier from
a FunctionDecl. I believe this information is only available earlier in
the AST construction from DeclSpec::getStorageClassSpecLoc(), but we
don't have that here.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D59402
llvm-svn: 363749
Summary:
There was a search for non-prototype declarations for the function, but
we only showed the results for zero-parameter functions. Now we show the
note for functions with parameters as well, but we omit the fix-it hint
suggesting to add `void`.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D62750
llvm-svn: 363748
The device code must use the same long double type as the host.
Otherwise the code cannot be linked and executed properly. Patch adds
only basic support and checks for supporting of the host long double
double on the device.
llvm-svn: 363717
Reland r363242 after fixing an issue with the tablegen dependence.
Patch by Pierre Gondois and Sven van Haastregt.
Differential revision: https://reviews.llvm.org/D62849
llvm-svn: 363541
Summary:
When using ConstantExpr we often need the result of the expression to be kept in the AST. Currently this is done on a by the node that needs the result and has been done multiple times for enumerator, for constexpr variables... . This patch adds to ConstantExpr the ability to store the result of evaluating the expression. no functional changes expected.
Changes:
- Add trailling object to ConstantExpr that can hold an APValue or an uint64_t. the uint64_t is here because most ConstantExpr yield integral values so there is an optimized layout for integral values.
- Add basic* serialization support for the trailing result.
- Move conversion functions from an enum to a fltSemantics from clang::FloatingLiteral to llvm::APFloatBase. this change is to make it usable for serializing APValues.
- Add basic* Import support for the trailing result.
- ConstantExpr created in CheckConvertedConstantExpression now stores the result in the ConstantExpr Node.
- Adapt AST dump to print the result when present.
basic* : None, Indeterminate, Int, Float, FixedPoint, ComplexInt, ComplexFloat,
the result is not yet used anywhere but for -ast-dump.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: rnkovacs, hiraditya, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62399
llvm-svn: 363493
Summary:
Since the addition of __builtin_is_constant_evaluated the result of an expression can change based on whether it is evaluated in constant context. a lot of semantic checking performs evaluations with out specifying context. which can lead to wrong diagnostics.
for example:
```
constexpr int i0 = (long long)__builtin_is_constant_evaluated() * (1ll << 33); //#1
constexpr int i1 = (long long)!__builtin_is_constant_evaluated() * (1ll << 33); //#2
```
before the patch, #2 was diagnosed incorrectly and #1 wasn't diagnosed.
after the patch #1 is diagnosed as it should and #2 isn't.
Changes:
- add a flag to Sema to passe in constant context mode.
- in SemaChecking.cpp calls to Expr::Evaluate* are now done in constant context when they should.
- in SemaChecking.cpp diagnostics for UB are not checked for in constant context because an error will be emitted by the constant evaluator.
- in SemaChecking.cpp diagnostics for construct that cannot appear in constant context are not checked for in constant context.
- in SemaChecking.cpp diagnostics on constant expression are always emitted because constant expression are always evaluated.
- semantic checking for initialization of constexpr variables is now done in constant context.
- adapt test that were depending on warning changes.
- add test.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D62009
llvm-svn: 363488
Summary: This patch avoids the emission of maps for target link variables when unified memory is present.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: guansong, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D60883
llvm-svn: 363435
In addition to being unused and duplicating code, this was also wrong
(it didn't properly mark the operand as being potentially not odr-used).
This reinstates r363340, reverted in r363352.
llvm-svn: 363430
nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
This reinstates r363337, reverted in r363352.
llvm-svn: 363429
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.
This reinstates r363295, reverted in r363352, with a fix for PR42276:
we now produce a proper name for a non-odr-use reference to a static
constexpr data member. The name <mangled-name>.const is used in that
case; such names are reserved to the implementation for cases such as
this and should demangle nicely.
Reviewers: rjmccall
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63157
llvm-svn: 363428
This reverts commit r363242 as it broke some builds with
make[2]: *** No rule to make target 'ClangOpenCLBuiltinsImpl', needed by
'tools/clang/lib/Sema/CMakeFiles/obj.clangSema.dir/SemaLookup.cpp.o'.
llvm-svn: 363376
Summary:
this revision adds Lexing, Parsing and Basic Semantic for the consteval specifier as specified by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1073r3.html
with this patch, the consteval specifier is treated as constexpr but can only be applied to function declaration.
Changes:
- add the consteval keyword.
- add parsing of consteval specifier for normal declarations and lambdas expressions.
- add the whether a declaration is constexpr is now represented by and enum everywhere except for variable because they can't be consteval.
- adapt diagnostic about constexpr to print constexpr or consteval depending on the case.
- add tests for basic semantic.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: eraman, efriedma, rnkovacs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61790
llvm-svn: 363362
Summary:
[[ https://bugs.llvm.org/show_bug.cgi?id=41549 | bug report ]]
Before this patch, implicit deduction guides were generated from the first declaration found by lookup.
With this patch implicit deduction guides are generated from the definition of the class template.
Also added test that was previously failing.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits, Quuxplusone
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63072
llvm-svn: 363361
Summary:
this is a bugfixe for [[ https://bugs.llvm.org/show_bug.cgi?id=41400 | PR41400 ]]
added nullptr check at the relevent place and test
Reviewers: rsmith, riccibruno
Reviewed By: rsmith
Subscribers: jkooker, jkorous, riccibruno, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D60523
llvm-svn: 363360
Revert 363340 "Remove unused SK_LValueToRValue initialization step."
Revert 363337 "PR23833, DR2140: an lvalue-to-rvalue conversion on a glvalue of type"
Revert 363295 "C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression."
llvm-svn: 363352
In addition to being unused and duplicating code, this was also wrong
(it didn't properly mark the operand as being potentially not odr-used).
llvm-svn: 363340
nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
This reinstates r345562, reverted in r346065, now that CodeGen's
handling of non-odr-used variables has been fixed.
llvm-svn: 363337
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.
Reviewers: rjmccall
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63157
llvm-svn: 363295
Functions using stdcall, fastcall, or vectorcall with C linkage mangle
in the size of the parameter pack. Calculating the size of the pack
requires the parameter types to complete, which may require template
instantiation.
Previously, we would crash during IRgen when requesting the size of
incomplete or uninstantiated types, as in this reduced example:
struct Foo;
void __fastcall bar(struct Foo o);
void (__fastcall *fp)(struct Foo) = &bar;
Reported in Chromium here: https://crbug.com/971245
Differential Revision: https://reviews.llvm.org/D62975
llvm-svn: 363000
Summary:
- when a method is not available because of the target value kind (e.g. an &&
method on a Foo& variable), then don't offer it.
- when a method is effectively shadowed by another method from the same class
with a) an identical argument list and b) superior qualifiers, then don't
offer it.
Reviewers: ilya-biryukov
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D62582
llvm-svn: 362785
most / all other Expr subclasses.
This reinstates r362551, reverted in r362597, with a fix to a bug that
caused MemberExprs to sometimes have a null FoundDecl after a round-trip
through an AST file.
llvm-svn: 362756
As reported in https://bugs.llvm.org/show_bug.cgi?id=42113, there are a
number of locations in Clang where it is assumed that exception
specifications are only valid in C++ mode. Since the original
justification for the NoThrow Exception Specifier Type was C++ related,
this patch just makes C mode use the attribute-based nothrow handling.
Additionally, I noticed that the handling of non-prototype functions
regressed the behavior of the nothrow attribute, in part because it is
was listed in the function type macro(which I did in the previous
patch). In reality, it should only be doing so in a conditional nature,
so this patch removes it there and puts it directly in the switch to be
handled correctly.
llvm-svn: 362607
References to arbitrary address spaces can't always be bound to
temporaries. This change extends the reference binding logic to
check that the address space of a temporary can be implicitly
converted to the address space in a reference when temporary
materialization is performed.
Differential Revision: https://reviews.llvm.org/D61318
llvm-svn: 362604