This is a followup patch for https://reviews.llvm.org/D61809.
Handle unnamed bitfield properly and add more test cases.
Fixed the unnamed bitfield issue. The unnamed bitfield is ignored
by debug info, so we need to ignore such a struct/union member
when we try to get the member index in the debug info.
D61809 contains two test cases but not enough as it does
not checking generated IRs in the fine grain level, and also
it does not have semantics checking tests.
This patch added unit tests for both code gen and semantics checking for
the new intrinsic.
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 366076
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
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
Attach a unique DISubprogram to a function declaration that will be
used for call site debug info.
([7/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D60714
llvm-svn: 364502
A handful of C++ cases as reported in PR42352 didn't actually give an
error when always_inlining with a different target feature list. This
resulted in broken IR.
llvm-svn: 364109
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
Summary:
This patch adds support for the handling of the variables under the declare target to clause.
The variables in this case are handled like link variables are. A pointer is created on the host and then mapped to the device. The runtime will then copy the address of the host variable in the device pointer.
Reviewers: ABataev, AlexEichenberger, caomhin
Reviewed By: ABataev
Subscribers: guansong, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63108
llvm-svn: 363959
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
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
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
Summary:
This patch implements the source location builtins `__builtin_LINE(), `__builtin_FUNCTION()`, `__builtin_FILE()` and `__builtin_COLUMN()`. These builtins are needed to implement [`std::experimental::source_location`](https://rawgit.com/cplusplus/fundamentals-ts/v2/main.html#reflection.src_loc.creation).
With the exception of `__builtin_COLUMN`, GCC also implements these builtins, and Clangs behavior is intended to match as closely as possible.
Reviewers: rsmith, joerg, aaron.ballman, bogner, majnemer, shafik, martong
Reviewed By: rsmith
Subscribers: rnkovacs, loskutov, riccibruno, mgorny, kunitoki, alexr, majnemer, hfinkel, cfe-commits
Differential Revision: https://reviews.llvm.org/D37035
llvm-svn: 360937
This follows up after b7692bc3e9 "[UBSan] Fix
isDerivedFromAtOffset on iOS ARM64" fixed the RTTI comparison in
isDerivedFromAtOffset on just one platform and then
a25a2c7c9a "Always compare C++ typeinfo (based on
libstdc++ implementation)" extended that fix to more platforms.
But there is another RTTI comparison for -fsanitize=function generated in
clang's CodeGenFunction::EmitCall as just a pointer comparison. For
SANITIZER_NON_UNIQUE_TYPEINFO platforms this needs to be extended to also do
string comparison. For that, __ubsan_handle_function_type_mismatch[_abort]
takes the two std::type_info pointers as additional parameters now, checks them
internally for potential equivalence, and returns without reporting failure if
they turn out to be equivalent after all. (NORETURN needed to be dropped from
the _abort variant for that.) Also these functions depend on ABI-specific RTTI
now, so needed to be moved from plain UBSAN_SOURCES (ubsan_handlers.h/cc) to
UBSAN_CXXABI_SOURCES (ubsan_handlers_cxx.h/cc), but as -fsanitize=function is
only supported in C++ mode that's not a problem.
Differential Revision: https://reviews.llvm.org/D60760
llvm-svn: 359759
This ability was removed in r351487, but it's needed when a lambda appears as an
OpaqueValueExpr subexpression of a PseudoObjectExpr.
rdar://49030379
Differential revision: https://reviews.llvm.org/D60099
llvm-svn: 357515
This patch includes the necessary code for converting between a fixed point type and integer.
This also includes constant expression evaluation for conversions with these types.
Differential Revision: https://reviews.llvm.org/D56900
llvm-svn: 355462
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".
This is a recommit of r354873 but with a fix for unqualified lookup error in lldb cmake build bot.
Fixes: https://llvm.org/PR39425
Differential Revision: https://reviews.llvm.org/D57914
llvm-svn: 355190
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".
Fixes: https://llvm.org/PR39425
Differential Revision: https://reviews.llvm.org/D57914
llvm-svn: 354873
The various EltSize, Offset, DataLayout, and StructLayout arguments
are all computable from the Address's element type and the DataLayout
which the CGBuilder already has access to.
After having previously asserted that the computed values are the same
as those passed in, now remove the redundant arguments from
CGBuilder's Create*GEP functions.
Differential Revision: https://reviews.llvm.org/D57767
llvm-svn: 353629
Some of these functions take some extraneous arguments, e.g. EltSize,
Offset, which are computable from the Type and DataLayout.
Add some asserts to ensure that the computed values are consistent
with the passed-in values, in preparation for eliminating the
extraneous arguments. This also asserts that the Type is an Array for
the calls named "Array" and a Struct for the calls named "Struct".
Then, correct a couple of errors:
1. Using CreateStructGEP on an array type. (this causes the majority
of the test differences, as struct GEPs are created with i32
indices, while array GEPs are created with i64 indices)
2. Passing the wrong Offset to CreateStructGEP in TargetInfo.cpp on
x86-64 NACL (which uses 32-bit pointers).
Differential Revision: https://reviews.llvm.org/D57766
llvm-svn: 353529
Emit{Nounwind,}RuntimeCall{,OrInvoke} have been modified to take a
FunctionCallee as an argument, and CreateRuntimeFunction has been
modified to return a FunctionCallee. All callers have been updated.
Additionally, CreateBuiltinFunction is removed, as it was redundant
with CreateRuntimeFunction after some previous changes.
Differential Revision: https://reviews.llvm.org/D57668
llvm-svn: 353184
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.
Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
llvm-svn: 352827
This reverts commit f47d6b38c7 (r352791).
Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.
llvm-svn: 352800
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
llvm-svn: 352791
This is meant to be used with clang's __builtin_dynamic_object_size.
When 'true' is passed to this parameter, the intrinsic has the
potential to be folded into instructions that will be evaluated
at run time. When 'false', the objectsize intrinsic behaviour is
unchanged.
rdar://32212419
Differential revision: https://reviews.llvm.org/D56761
llvm-svn: 352664
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Lambda captures should be destroyed if an exception is thrown only if
the construction of the complete lambda-expression has not completed.
(If the lambda-expression has been fully constructed, any exception will
invoke its destructor, which will destroy the captures.)
This is directly modeled after how we handle the equivalent situation in
InitListExprs.
Note that EmitLambdaLValue was unreachable because in C++11 onwards the
frontend never creates the awkward situation where a prvalue expression
(such as a lambda) is used in an lvalue context (such as the left-hand
side of a class member access).
llvm-svn: 351487
This attribute, called "objc_externally_retained", exposes clang's
notion of pseudo-__strong variables in ARC. Pseudo-strong variables
"borrow" their initializer, meaning that they don't retain/release
it, instead assuming that someone else is keeping their value alive.
If a function is annotated with this attribute, implicitly strong
parameters of that function aren't implicitly retained/released in
the function body, and are implicitly const. This is useful to expose
for performance reasons, most functions don't need the extra safety
of the retain/release, so programmers can opt out as needed.
This attribute can also apply to declarations of local variables,
with similar effect.
Differential revision: https://reviews.llvm.org/D55865
llvm-svn: 350422
Address spaces are cast into generic before invoking the constructor.
Added support for a trailing Qualifiers object in FunctionProtoType.
Note: This recommits the previously reverted patch,
but now it is commited together with a fix for lldb.
Differential Revision: https://reviews.llvm.org/D54862
llvm-svn: 349019
Address spaces are cast into generic before invoking the constructor.
Added support for a trailing Qualifiers object in FunctionProtoType.
Differential Revision: https://reviews.llvm.org/D54862
llvm-svn: 348927
Function calls without a !dbg location inside a function that has a
DISubprogram make it impossible to construct inline information and
are rejected by the verifier. This patch ensures that sanitizer check
function calls have a !dbg location, by carrying forward the location
of the preceding instruction or by inserting an artificial location if
necessary.
This fixes a crash when compiling the attached testcase with -Os.
rdar://problem/45311226
Differential Revision: https://reviews.llvm.org/D53459
Note: This reapllies r344915, modified to reuse the IRBuilder's
DebugLoc if one exists instead of picking the one from CGDebugInfo
since the latter may get reset when emitting thunks such as block
helpers in the middle of emitting another function.
llvm-svn: 347810
Added references to the addr spaces deduction and enabled
CL2.0 features (program scope variables and storage class
qualifiers) to work in C++ mode too.
Fixed several address space conversion issues in CodeGen
for references.
Differential Revision: https://reviews.llvm.org/D53764
llvm-svn: 347059
As suggested by Richard Smith, and initially put up for review here:
https://reviews.llvm.org/D53341, this patch removes a hack that was used
to ensure that proper target-feature lists were used when emitting
cpu-dispatch (and eventually, target-clones) implementations. As a part
of this, the GlobalDecl object is proliferated to a bunch more
locations.
Originally, this was put up for review (see above) to get acceptance on
the approach, though discussion with Richard in San Diego showed he
approved of the approach taken here. Thus, I believe this is acceptable
for Review-After-commit
Differential Revision: https://reviews.llvm.org/D53341
Change-Id: I0a0bd673340d334d93feac789d653e03d9f6b1d5
llvm-svn: 346757
Summary:
Compound literals, enums, file-scoped arrays, etc. require their
initializers and size specifiers to be constant. Wrap the initializer
expressions in a ConstantExpr so that we can easily check for this later
on.
Reviewers: rsmith, shafik
Reviewed By: rsmith
Subscribers: cfe-commits, jyknight, nickdesaulniers
Differential Revision: https://reviews.llvm.org/D53921
llvm-svn: 346455
The goal is to use `emitConstant` in more places. Didn't move
`ComplexExprEmitter::emitConstant` because it returns a different type.
Reviewers: rjmccall, ahatanak
Reviewed By: rjmccall
Subscribers: dexonsmith, erik.pilkington, cfe-commits
Differential Revision: https://reviews.llvm.org/D53725
llvm-svn: 345897
We haven't supported compiling ObjC1 for a long time (and never will again), so
there isn't any reason to keep these separate. This patch replaces
LangOpts::ObjC1 and LangOpts::ObjC2 with LangOpts::ObjC.
Differential revision: https://reviews.llvm.org/D53547
llvm-svn: 345637
Make the following changes to PredefinedExpr:
1. Move PredefinedExpr below StringLiteral so that it can use its definition.
2. Rename IdentType to IdentKind to be more in line with clang's conventions,
and propagate the change to its users.
3. Move the location and the IdentKind into the newly available space of
the bit-fields of Stmt.
4. Only store the function name when needed. When parsing all of Boost,
of the 1357 PredefinedExpr 919 have no function name.
Differential Revision: https://reviews.llvm.org/D53605
Reviewed By: rjmccall
llvm-svn: 345460
This patch is a part of https://reviews.llvm.org/D48456 in an attempt to split
the casting logic up into smaller patches. This contains the code for casting
from fixed point types to boolean types.
Differential Revision: https://reviews.llvm.org/D53308
llvm-svn: 345063
Function calls without a !dbg location inside a function that has a
DISubprogram make it impossible to construct inline information and
are rejected by the verifier. This patch ensures that sanitizer check
function calls have a !dbg location, by carrying forward the location
of the preceding instruction or by inserting an artificial location if
necessary.
This fixes a crash when compiling the attached testcase with -Os.
rdar://problem/45311226
Differential Revision: https://reviews.llvm.org/D53459
llvm-svn: 344915
This patch is a part of https://reviews.llvm.org/D48456 in an attempt to
split them up. This contains the code for casting between fixed point types
and other fixed point types.
The method for converting between fixed point types is based off the convert()
method in APFixedPoint.
Differential Revision: https://reviews.llvm.org/D50616
llvm-svn: 344530
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
This reapplies r343518 after fixing a use-after-free bug in function
Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after
it was popped and deleted.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 343542
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
This reapplies r341754, which was reverted in r341757 because it broke a
couple of bots. r341754 was calling markEscapingByrefs after the call to
PopFunctionScopeInfo, which caused the popped function scope to be
cleared out when the following code was compiled, for example:
$ cat test.m
struct A {
id data[10];
};
void foo() {
__block A v;
^{ (void)v; };
}
This commit calls markEscapingByrefs before calling PopFunctionScopeInfo
to prevent that from happening.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 343518
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 341754
by a block.
Added checks for capturing of the variable in the block when trying to
emit correct address for the variable with the reference type. This
extra check allows correctly identify the variables that are not
captured in the block context.
llvm-svn: 340181
The compiler may produce unexpected error messages/crashes when declare
target variables were used. Patch fixes problems with the declarations
marked as declare target to or link.
llvm-svn: 339805
When a non-extended temporary object is created in a conditional branch, the
lifetime of that temporary ends outside the conditional (at the end of the
full-expression). If we're inserting lifetime markers, this means we could end
up generating
if (some_cond) {
lifetime.start(&tmp);
Tmp::Tmp(&tmp);
}
// ...
if (some_cond) {
lifetime.end(&tmp);
}
... for a full-expression containing a subexpression of the form `some_cond ?
Tmp().x : 0`. This patch moves the lifetime start for such a temporary out of
the conditional branch so that we don't need to generate an additional basic
block to hold the lifetime end marker.
This is disabled if we want precise lifetime markers (for asan's
stack-use-after-scope checks) or of the temporary has a non-trivial destructor
(in which case we'd generate an extra basic block anyway to hold the destructor
call).
Differential Revision: https://reviews.llvm.org/D50286
llvm-svn: 338945
Summary:
Emmiting new intrinsic that strips invariant.groups to make
devirtulization sound, as described in RFC: Devirtualization v2.
Reviewers: rjmccall, rsmith, amharc, kuhar
Subscribers: llvm-commits, cfe-commits
Differential Revision: https://reviews.llvm.org/D47299
Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336137
Introduced CreateMemTempWithoutCast and CreateTemporaryAllocaWithoutCast to emit alloca
without casting to default addr space.
ActiveFlag is a temporary variable emitted for clean up. It is defined as AllocaInst* type and there is
a cast to AlllocaInst in SetActiveFlag. An alloca casted to generic pointer causes assertion in
SetActiveFlag.
Since there is only load/store of ActiveFlag, it is safe to use the original alloca, therefore use
CreateMemTempWithoutCast is called.
Differential Revision: https://reviews.llvm.org/D47099
llvm-svn: 332982
lifetime.start/end expects pointer argument in alloca address space.
However in C++ a temporary variable is in default address space.
This patch changes API CreateMemTemp and CreateTempAlloca to
get the original alloca instruction and pass it lifetime.start/end.
It only affects targets with non-zero alloca address space.
Differential Revision: https://reviews.llvm.org/D45900
llvm-svn: 332593
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
When we enter a __finally block, the CGF's CurCodeDecl will be null
(because CodeGenFunction::StartFunction is given an empty GlobalDecl for
a __finally block), and so the dyn_cast here will result in an assertion
failure. Change it to dyn_cast_or_null to handle this case.
Differential Revision: https://reviews.llvm.org/D45523
llvm-svn: 329836
the tail padding is not reused.
We track on the AggValueSlot (and through a couple of other
initialization actions) whether we're dealing with an object that might
share its tail padding with some other object, so that we can avoid
emitting stores into the tail padding if that's the case. We still
widen stores into tail padding when we can do so.
Differential Revision: https://reviews.llvm.org/D45306
llvm-svn: 329342
variables.
Added emission of the offloading data sections for the variables within
declare target regions + fixes emission of the declare target variables
marked as declare target not within the declare target region.
llvm-svn: 328888
If the link clause is used on the declare target directive, the object
should be linked on target or target data directives, not during the
codegen. Patch adds support for this clause.
llvm-svn: 328544
source expressions when iterating over a PseudoObjectExpr's semantic
subexpression list.
Previously the loop in emitPseudoObjectExpr would emit the IR for each
OpaqueValueExpr that was in a PseudoObjectExpr's semantic-form
expression list and use the result when the OpaqueValueExpr later
appeared in other expressions. This caused an assertion failure when
AggExprEmitter tried to copy the result of an OpaqueValueExpr and the
copied type didn't have trivial copy/move constructors or assignment
operators.
This patch adds flag IsUnique to OpaqueValueExpr which indicates it is a
unique reference to its source expression (it is not used in multiple
places). The loop in emitPseudoObjectExpr ignores OpaqueValueExprs that
are unique and CodeGen visitors simply traverse the source expressions
of such OpaqueValueExprs.
rdar://problem/34363596
Differential Revision: https://reviews.llvm.org/D39562
llvm-svn: 327939
Summary:
This patch enables debugging of C99 VLA types by generating more precise
LLVM Debug metadata, using the extended DISubrange 'count' field that
takes a DIVariable.
This should implement:
Bug 30553: Debug info generated for arrays is not what GDB expects (not as good as GCC's)
https://bugs.llvm.org/show_bug.cgi?id=30553
Reviewers: echristo, aprantl, dexonsmith, clayborg, pcc, kristof.beyls, dblaikie
Reviewed By: aprantl
Subscribers: jholewinski, schweitz, davide, fhahn, JDevlieghere, cfe-commits
Differential Revision: https://reviews.llvm.org/D41698
llvm-svn: 323952
As discussed in the mail thread <https://groups.google.com/a/isocpp.org/forum/
#!topic/std-discussion/T64_dW3WKUk> "Calling noexcept function throug non-
noexcept pointer is undefined behavior?", such a call should not be UB.
However, Clang currently warns about it.
This change removes exception specifications from the function types recorded
for -fsanitize=function, both in the functions themselves and at the call sites.
That means that calling a non-noexcept function through a noexcept pointer will
also not be flagged as UB. In the review of this change, that was deemed
acceptable, at least for now. (See the "TODO" in compiler-rt
test/ubsan/TestCases/TypeCheck/Function/function.cpp.)
To remove exception specifications from types, the existing internal
ASTContext::getFunctionTypeWithExceptionSpec was made public, and some places
otherwise unrelated to this change have been adapted to call it, too.
This is the cfe part of a patch covering both cfe and compiler-rt.
Differential Revision: https://reviews.llvm.org/D40720
llvm-svn: 321859
only.
Added support for -fopenmp-simd option that allows compilation of
simd-based constructs without emission of OpenMP runtime calls.
llvm-svn: 321560
...when such an operation is done on an object during con-/destruction.
This is the cfe part of a patch covering both cfe and compiler-rt.
Differential Revision: https://reviews.llvm.org/D40295
llvm-svn: 321519
The new format requires to specify both the type of the access
and its size. This patch fixes setting access sizes for TBAA tags
that denote accesses to structure members. This fix affects all
future TBAA metadata tests for the new format, so I guess we
don't need any special tests for this fix.
Differential Revision: https://reviews.llvm.org/D41452
llvm-svn: 321250
Diagnose 'unreachable' UB when a noreturn function returns.
1. Insert a check at the end of functions marked noreturn.
2. A decl may be marked noreturn in the caller TU, but not marked in
the TU where it's defined. To diagnose this scenario, strip away the
noreturn attribute on the callee and insert check after calls to it.
Testing: check-clang, check-ubsan, check-ubsan-minimal, D40700
rdar://33660464
Differential Revision: https://reviews.llvm.org/D40698
llvm-svn: 321231
At least <http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-android/
builds/6013/steps/annotate/logs/stdio> complains about
__ubsan::__ubsan_handle_function_type_mismatch_abort (compiler-rt
lib/ubsan/ubsan_handlers.cc) returning now despite being declared 'noreturn', so
looks like a different approach is needed for the function_type_mismatch check
to be called also in cases that may ultimately succeed.
llvm-svn: 320982
As discussed in the mail thread <https://groups.google.com/a/isocpp.org/forum/
#!topic/std-discussion/T64_dW3WKUk> "Calling noexcept function throug non-
noexcept pointer is undefined behavior?", such a call should not be UB.
However, Clang currently warns about it.
There is no cheap check whether two function type_infos only differ in noexcept,
so pass those two type_infos as additional data to the function_type_mismatch
handler (with the optimization of passing a null "static callee type" info when
that is already noexcept, so the additional check can be avoided anyway). For
the Itanium ABI (which appears to be the only one that happens to be used on
platforms that support -fsanitize=function, and which appears to only record
noexcept information for pointer-to-function type_infos, not for function
type_infos themselves), we then need to check the mangled names for occurrence
of "Do" representing "noexcept".
This is the cfe part of a patch covering both cfe and compiler-rt.
Differential Revision: https://reviews.llvm.org/D40720
llvm-svn: 320978
Most of the -Wsign-compare warnings are due to the fact that
enums are signed by default in the MS ABI, while the
tautological comparison warnings trigger on x86 builds where
sizeof(size_t) is 4 bytes, so N > numeric_limits<unsigned>::max()
is always false.
Differential Revision: https://reviews.llvm.org/D41256
llvm-svn: 320750
This is a follow-up to r320128. Eli pointed out that there is some gray
area in the language standard about whether the constant size is exact,
or a lower bound.
https://reviews.llvm.org/D40940
llvm-svn: 320185
The basic idea behind this patch is that since in strict aliasing
mode all accesses to union members require their outermost
enclosing union objects to be specified explicitly, then for a
couple given accesses to union members of the form
p->a.b.c...
q->x.y.z...
it is known they can only alias if both p and q point to the same
union type and offset ranges of members a.b.c... and x.y.z...
overlap. Note that the actual types of the members do not matter.
Specifically, in this patch we do the following:
* Make unions to be valid TBAA base access types. This enables
generation of TBAA type descriptors for unions.
* Encode union types as structures with a single member of a
special "union member" type. Currently we do not encode
information about sizes of types, but conceptually such union
members are considered to be of the size of the whole union.
* Encode accesses to direct and indirect union members, including
member arrays, as accesses to these special members. All
accesses to members of a union thus get the same offset, which
is the offset of the union they are part of. This means the
existing LLVM TBAA machinery is able to handle such accesses
with no changes.
While this is already an improvement comparing to the current
situation, that is, representing all union accesses as may-alias
ones, there are further changes planned to complete the support
for unions. One of them is storing information about access sizes
so we can distinct accesses to non-overlapping union members,
including accesses to different elements of member arrays.
Another change is encoding type sizes in order to make it
possible to compute offsets within constant-indexed array
elements. These enhancements will be addressed with separate
patches.
Differential Revision: https://reviews.llvm.org/D39455
llvm-svn: 319413
Summary:
This change allows generalizing pointers in type signatures used for
cfi-icall by enabling the -fsanitize-cfi-icall-generalize-pointers flag.
This works by 1) emitting an additional generalized type signature
metadata node for functions and 2) llvm.type.test()ing for the
generalized type for translation units with the flag specified.
This flag is incompatible with -fsanitize-cfi-cross-dso because it would
require emitting twice as many type hashes which would increase artifact
size.
Reviewers: pcc, eugenis
Reviewed By: pcc
Subscribers: kcc
Differential Revision: https://reviews.llvm.org/D39358
llvm-svn: 317044
This patch fixes various places in clang to propagate may-alias
TBAA access descriptors during construction of lvalues, thus
eliminating the need for the LValueBaseInfo::MayAlias flag.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D39008
llvm-svn: 316988
For non-zero alloca addr space, alloca is usually casted to default addr
space immediately.
For non-vla, alloca is inserted at AllocaInsertPt, therefore the addr
space cast should also be insterted at AllocaInsertPt. However,
for vla, alloca is inserted at the current insertion point of IRBuilder,
therefore the addr space cast should also inserted at the current
insertion point of IRBuilder.
Currently clang always insert addr space cast at AllocaInsertPt, which
causes invalid IR.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D39374
llvm-svn: 316909
Builder save/restores insertion pointer when emitting addr space cast
for alloca, but does not save/restore debug loc, which causes verifier
failure for certain call instructions.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D39069
llvm-svn: 316484
The main change is that now we generate TBAA info before
constructing the resulting lvalue instead of constructing lvalue
with some default TBAA info and fixing it as necessary
afterwards. We also keep the TBAA info close to lvalue base info,
which is supposed to simplify their future merging.
This patch should not bring in any functional changes.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38947
llvm-svn: 315989
This patch addresses the rest of the cases where we pass lvalue
base info, but do not provide corresponding TBAA info.
This patch should not bring in any functional changes.
This is part of D38126 reworked to be a separate patch to make
reviewing easier.
Differential Revision: https://reviews.llvm.org/D38945
llvm-svn: 315986
This patch enables explicit generation of TBAA information in all
cases where LValue base info is propagated or constructed in
non-trivial ways. Eventually, we will consider each of these
cases to make sure the TBAA information is correct and not too
conservative. For now, we just fall back to generating TBAA info
from the access type.
This patch should not bring in any functional changes.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38733
llvm-svn: 315575
Besides obvious code simplification, avoiding explicit creation
of LValueBaseInfo objects makes it easier to make TBAA
information to be part of such objects.
This is part of D38126 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38695
llvm-svn: 315289
In C++11 variable to global variables are considered as constant
expressions and these variables are not captured in the outlined
regions. Patch allows capturing of such variables in the OpenMP regions.
llvm-svn: 315074
This patch is an attempt to clarify and simplify generation and
propagation of TBAA information. The idea is to pack all values
that describe a memory access, namely, base type, access type and
offset, into a single structure. This is supposed to make further
changes, such as adding support for unions and array members,
easier to prepare and review.
DecorateInstructionWithTBAA() is no more responsible for
converting types to tags. These implicit conversions not only
complicate reading the code, but also suggest assigning scalar
access tags while we generally prefer full-size struct-path tags.
TBAAPathTag is replaced with TBAAAccessInfo; the latter is now
the type of the keys of the cache map that translates access
descriptors to metadata nodes.
Fixed a bug with writing to a wrong map in
getTBAABaseTypeMetadata() (former getTBAAStructTypeInfo()).
We now check for valid base access types every time we
dereference a field. The original code only checks the top-level
base type. See isValidBaseType() / isTBAAPathStruct() calls.
Some entities have been renamed to sound more adequate and less
confusing/misleading in presence of path-aware TBAA information.
Now we do not lookup twice for the same cache entry in
getAccessTagInfo().
Refined relevant comments and descriptions.
Differential Revision: https://reviews.llvm.org/D37826
llvm-svn: 315048
This patch makes it possible to produce access tags in a uniform
manner regardless whether the resulting tag will be a scalar or a
struct-path one. getAccessTagInfo() now takes care of the actual
translation of access descriptors to tags and can handle all
kinds of accesses. Facilities that specific to scalar accesses
are eliminated.
Some more details:
* DecorateInstructionWithTBAA() is not responsible for conversion
of types to access tags anymore. Instead, it takes an access
descriptor (TBAAAccessInfo) and generates corresponding access
tag from it.
* getTBAAInfoForVTablePtr() reworked to
getTBAAVTablePtrAccessInfo() that now returns the
virtual-pointer access descriptor and not the virtual-point
type metadata.
* Added function getTBAAMayAliasAccessInfo() that returns the
descriptor for may-alias accesses.
* getTBAAStructTagInfo() renamed to getTBAAAccessTagInfo() as now
it is the only way to generate access tag by a given access
descriptor. It is capable of producing both scalar and
struct-path tags, depending on options and availability of the
base access type. getTBAAScalarTagInfo() and its cache
ScalarTagMetadataCache are eliminated.
* Now that we do not need to care about whether the resulting
access tag should be a scalar or struct-path one,
getTBAAStructTypeInfo() is renamed to getBaseTypeInfo().
* Added function getTBAAAccessInfo() that constructs access
descriptor by a given QualType access type.
This is part of D37826 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38503
llvm-svn: 314979
This patch makes it possible to produce access tags in a uniform
manner regardless whether the resulting tag will be a scalar or a
struct-path one. getAccessTagInfo() now takes care of the actual
translation of access descriptors to tags and can handle all
kinds of accesses. Facilities that specific to scalar accesses
are eliminated.
Some more details:
* DecorateInstructionWithTBAA() is not responsible for conversion
of types to access tags anymore. Instead, it takes an access
descriptor (TBAAAccessInfo) and generates corresponding access
tag from it.
* getTBAAInfoForVTablePtr() reworked to
getTBAAVTablePtrAccessInfo() that now returns the
virtual-pointer access descriptor and not the virtual-point
type metadata.
* Added function getTBAAMayAliasAccessInfo() that returns the
descriptor for may-alias accesses.
* getTBAAStructTagInfo() renamed to getTBAAAccessTagInfo() as now
it is the only way to generate access tag by a given access
descriptor. It is capable of producing both scalar and
struct-path tags, depending on options and availability of the
base access type. getTBAAScalarTagInfo() and its cache
ScalarTagMetadataCache are eliminated.
* Now that we do not need to care about whether the resulting
access tag should be a scalar or struct-path one,
getTBAAStructTypeInfo() is renamed to getBaseTypeInfo().
* Added function getTBAAAccessInfo() that constructs access
descriptor by a given QualType access type.
This is part of D37826 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38503
llvm-svn: 314977
With this patch we implement a concept of TBAA access descriptors
that are capable of representing both scalar and struct-path
accesses in a generic way.
This is part of D37826 reworked to be a separate patch to
simplify review.
Differential Revision: https://reviews.llvm.org/D38456
llvm-svn: 314780
Don't emit alignment checks which the IR constant folder throws away.
I've tested this out on X86FastISel.cpp. While this doesn't decrease
end-to-end compile-time significantly, it results in 122 fewer type
checks (1% reduction) overall, without adding any real complexity.
Differential Revision: https://reviews.llvm.org/D37544
llvm-svn: 314752
This patch fixes misleading names of entities related to getting,
setting and generation of TBAA access type descriptors.
This is effectively an attempt to provide a review for D37826 by
breaking it into smaller pieces.
Differential Revision: https://reviews.llvm.org/D38404
llvm-svn: 314657
Added missing addrspacecast case in alignment computation
logic of pointer type emission in IR generation.
Differential Revision: https://reviews.llvm.org/D37804
llvm-svn: 314304
Summary:
This is the follow-up patch to D37924.
This change refactors clang to use the the newly added section headers
in SpecialCaseList to specify which sanitizers blacklists entries
should apply to, like so:
[cfi-vcall]
fun:*bad_vcall*
[cfi-derived-cast|cfi-unrelated-cast]
fun:*bad_cast*
The SanitizerSpecialCaseList class has been added to allow querying by
SanitizerMask, and SanitizerBlacklist and its downstream users have been
updated to provide that information. Old blacklists not using sections
will continue to function identically since the blacklist entries will
be placed into a '[*]' section by default matching against all
sanitizers.
Reviewers: pcc, kcc, eugenis, vsk
Reviewed By: eugenis
Subscribers: dberris, cfe-commits, mgorny
Differential Revision: https://reviews.llvm.org/D37925
llvm-svn: 314171
This change will make it possible to use -fsanitize=function on Darwin and
possibly on other platforms. It fixes an issue with the way RTTI is stored into
function prologue data.
On Darwin, addresses stored in prologue data can't require run-time fixups and
must be PC-relative. Run-time fixups are undesirable because they necessitate
writable text segments, which can lead to security issues. And absolute
addresses are undesirable because they break PIE mode.
The fix is to create a private global which points to the RTTI, and then to
encode a PC-relative reference to the global into prologue data.
Differential Revision: https://reviews.llvm.org/D37597
llvm-svn: 313096
Because it is common to treat vector types as an array of their elements, or
even some other type that's not the element type, and thus index into them, we
can't use struct-path TBAA for these accesses. Even though we already treat all
vector types as equivalent to 'char', we were using field-offset information
for them with TBAA, and this renders undefined the intra-value indexing we
intend to allow. Note that, although 'char' is universally aliasing, with path
TBAA, we can still differentiate between access to s.a and s.b in
struct { char a, b; } s;. We can't use this capability as-is for vector types.
Fixes PR33967.
llvm-svn: 312447
Summary:
An implementation of ubsan runtime library suitable for use in production.
Minimal attack surface.
* No stack traces.
* Definitely no C++ demangling.
* No UBSAN_OPTIONS=log_file=/path (very suid-unfriendly). And no UBSAN_OPTIONS in general.
* as simple as possible
Minimal CPU and RAM overhead.
* Source locations unnecessary in the presence of (split) debug info.
* Values and types (as in A+B overflows T) can be reconstructed from register/stack dumps, once you know what type of error you are looking at.
* above two items save 3% binary size.
When UBSan is used with -ftrap-function=abort, sometimes it is hard to reason about failures. This library replaces abort with a slightly more informative message without much extra overhead. Since ubsan interface in not stable, this code must reside in compiler-rt.
Reviewers: pcc, kcc
Subscribers: srhines, mgorny, aprantl, krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D36810
llvm-svn: 312029
expressions
C++ allows us to reference static variables through member expressions. Prior to
this commit, non-integer static variables that were referenced using a member
expression were always emitted using lvalue loads. The old behaviour introduced
an inconsistency between regular uses of static variables and member expressions
uses. For example, the following program compiled and linked successfully:
struct Foo {
constexpr static const char *name = "foo";
};
int main() {
return Foo::name[0] == 'f';
}
but this program failed to link because "Foo::name" wasn't found:
struct Foo {
constexpr static const char *name = "foo";
};
int main() {
Foo f;
return f.name[0] == 'f';
}
This commit ensures that constant static variables referenced through member
expressions are emitted in the same way as ordinary static variable references.
rdar://33942261
Differential Revision: https://reviews.llvm.org/D36876
llvm-svn: 311772
of class fails to map class static variable.
If the global variable is captured and it has several redeclarations,
sometimes it may lead to a compiler crash. Patch fixes this by working
only with canonical declarations.
llvm-svn: 311479
the interface.
The ultimate goal here is to make it easier to do some more interesting
things in constant emission, like emit constant initializers that have
ignorable side-effects, or doing the majority of an initialization
in-place and then patching up the last few things with calls. But for
now this is mostly just a refactoring.
llvm-svn: 310964
OpenCL 2.0 atomic builtin functions have a scope argument which is ideally
represented as synchronization scope argument in LLVM atomic instructions.
Clang supports translating Clang atomic builtin functions to LLVM atomic
instructions. However it currently does not support synchronization scope
of LLVM atomic instructions. Without this, users have to use LLVM assembly
code to implement OpenCL atomic builtin functions.
This patch adds OpenCL 2.0 atomic builtin functions as Clang builtin
functions, which supports generating LLVM atomic instructions with
synchronization scope operand.
Currently only constant memory scope argument is supported. Support of
non-constant memory scope argument will be added later.
Differential Revision: https://reviews.llvm.org/D28691
llvm-svn: 310082
In r309007, I made -fsanitize=null a hard prerequisite for -fsanitize=vptr. I
did not see the need for the two checks to have separate null checking logic
for the same pointer. I expected the two checks to either always be enabled
together, or to be mutually compatible.
In the mailing list discussion re: r309007 it became clear that that isn't the
case. If a codebase is -fsanitize=vptr clean but not -fsanitize=null clean,
it's useful to have -fsanitize=vptr emit its own null check. That's what this
patch does: with it, -fsanitize=vptr can be used without -fsanitize=null.
Differential Revision: https://reviews.llvm.org/D36112
llvm-svn: 309846
The instrumentation generated by -fsanitize=vptr does not null check a
user pointer before loading from it. This causes crashes in the face of
UB member calls (this=nullptr), i.e it's causing user programs to crash
only after UBSan is turned on.
The fix is to make run-time null checking a prerequisite for enabling
-fsanitize=vptr, and to then teach UBSan to reuse these run-time null
checks to make -fsanitize=vptr safe.
Testing: check-clang, check-ubsan, a stage2 ubsan-enabled build
Differential Revision: https://reviews.llvm.org/D35735https://bugs.llvm.org/show_bug.cgi?id=33881
llvm-svn: 309007
The uses of alloca may be in different blocks other than the block containing the alloca.
Therefore if the alloca addr space is non-zero and it needs to be casted to default
address space, the cast needs to be inserted in the same BB as the alloca insted of
the current builder insert point since the current insert point may be in a different BB.
Differential Revision: https://reviews.llvm.org/D35438
llvm-svn: 308313
The pointer overflow check gives false negatives when dealing with
expressions in which an unsigned value is subtracted from a pointer.
This is summarized in PR33430 [1]: ubsan permits the result of the
subtraction to be greater than "p", but it should not.
To fix the issue, we should track whether or not the pointer expression
is a subtraction. If it is, and the indices are unsigned, we know to
expect "p - <unsigned> <= p".
I've tested this by running check-{llvm,clang} with a stage2
ubsan-enabled build. I've also added some tests to compiler-rt, which
are in D34122.
[1] https://bugs.llvm.org/show_bug.cgi?id=33430
Differential Revision: https://reviews.llvm.org/D34121
llvm-svn: 307955
Certain targets (e.g. amdgcn) require global variable to stay in global or constant address
space. In C or C++ global variables are emitted in the default (generic) address space.
This patch introduces virtual functions TargetCodeGenInfo::getGlobalVarAddressSpace
and TargetInfo::getConstantAddressSpace to handle this in a general approach.
It only affects IR generated for amdgcn target.
Differential Revision: https://reviews.llvm.org/D33842
llvm-svn: 307470
In C++ all variables are in default address space. Previously change has been
made to cast automatic variables to default address space. However that is
not sufficient since all temporary variables need to be casted to default
address space.
This patch casts all temporary variables to default address space except those
for passing indirect arguments since they are only used for load/store.
This patch only affects target having non-zero alloca address space.
Differential Revision: https://reviews.llvm.org/D33706
llvm-svn: 305711
Skip checks for null dereference, alignment violation, object size
violation, and dynamic type violation if the pointer points to volatile
data.
Differential Revision: https://reviews.llvm.org/D34262
llvm-svn: 305546
Summary:
The title says it all.
Reviewers: GorNishanov, rsmith
Reviewed By: GorNishanov
Subscribers: rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D34194
llvm-svn: 305496
Adding an unsigned offset to a base pointer has undefined behavior if
the result of the expression would precede the base. An example from
@regehr:
int foo(char *p, unsigned offset) {
return p + offset >= p; // This may be optimized to '1'.
}
foo(p, -1); // UB.
This patch extends the pointer overflow check in ubsan to detect invalid
unsigned pointer index expressions. It changes the instrumentation to
only permit non-negative offsets in pointer index expressions when all
of the GEP indices are unsigned.
Testing: check-llvm, check-clang run on a stage2, ubsan-instrumented
build.
Differential Revision: https://reviews.llvm.org/D33910
llvm-svn: 305216
Summary:
If the first parameter of the function is the ImplicitParamDecl, codegen
automatically marks it as an implicit argument with `this` or `self`
pointer. Added internal kind of the ImplicitParamDecl to separate
'this', 'self', 'vtt' and other implicit parameters from other kind of
parameters.
Reviewers: rjmccall, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33735
llvm-svn: 305075
Check pointer arithmetic for overflow.
For some more background on this check, see:
https://wdtz.org/catching-pointer-overflow-bugs.htmlhttps://reviews.llvm.org/D20322
Patch by Will Dietz and John Regehr!
This version of the patch is different from the original in a few ways:
- It introduces the EmitCheckedInBoundsGEP utility which inserts
checks when the pointer overflow check is enabled.
- It does some constant-folding to reduce instrumentation overhead.
- It does not check some GEPs in CGExprCXX. I'm not sure that
inserting checks here, or in CGClass, would catch many bugs.
Possible future directions for this check:
- Introduce CGF.EmitCheckedStructGEP, to detect overflows when
accessing structures.
Testing: Apart from the added lit test, I ran check-llvm and check-clang
with a stage2, ubsan-instrumented clang. Will and John have also done
extensive testing on numerous open source projects.
Differential Revision: https://reviews.llvm.org/D33305
llvm-svn: 304459
Summary:
We need to emit barrier if the union field
is CXXRecordDecl because it might have vptrs. The testcode
was wrongly devirtualized. It also proves that having different
groups for different dynamic types is not sufficient.
Reviewers: rjmccall, rsmith, mehdi_amini
Subscribers: amharc, cfe-commits
Differential Revision: https://reviews.llvm.org/D31830
llvm-svn: 304448
Rui Ueyama