This feature is generic. Make it applicable for AArch64 and X86 because
the backend has only implemented NOP insertion for AArch64 and X86.
Reviewed By: nickdesaulniers, aaron.ballman
Differential Revision: https://reviews.llvm.org/D72221
Summary:
Avoid using the `nocf_check` attribute with Control Flow Guard. Instead, use a
new `"guard_nocf"` function attribute to indicate that checks should not be
added on indirect calls within that function. Add support for
`__declspec(guard(nocf))` following the same syntax as MSVC.
Reviewers: rnk, dmajor, pcc, hans, aaron.ballman
Reviewed By: aaron.ballman
Subscribers: aaron.ballman, tomrittervg, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72167
This change introduces three new builtins (which work on both pointers
and integers) that can be used instead of common bitwise arithmetic:
__builtin_align_up(x, alignment), __builtin_align_down(x, alignment) and
__builtin_is_aligned(x, alignment).
I originally added these builtins to the CHERI fork of LLVM a few years ago
to handle the slightly different C semantics that we use for CHERI [1].
Until recently these builtins (or sequences of other builtins) were
required to generate correct code. I have since made changes to the default
C semantics so that they are no longer strictly necessary (but using them
does generate slightly more efficient code). However, based on our experience
using them in various projects over the past few years, I believe that adding
these builtins to clang would be useful.
These builtins have the following benefit over bit-manipulation and casts
via uintptr_t:
- The named builtins clearly convey the semantics of the operation. While
checking alignment using __builtin_is_aligned(x, 16) versus
((x & 15) == 0) is probably not a huge win in readably, I personally find
__builtin_align_up(x, N) a lot easier to read than (x+(N-1))&~(N-1).
- They preserve the type of the argument (including const qualifiers). When
using casts via uintptr_t, it is easy to cast to the wrong type or strip
qualifiers such as const.
- If the alignment argument is a constant value, clang can check that it is
a power-of-two and within the range of the type. Since the semantics of
these builtins is well defined compared to arbitrary bit-manipulation,
it is possible to add a UBSAN checker that the run-time value is a valid
power-of-two. I intend to add this as a follow-up to this change.
- The builtins avoids int-to-pointer casts both in C and LLVM IR.
In the future (i.e. once most optimizations handle it), we could use the new
llvm.ptrmask intrinsic to avoid the ptrtoint instruction that would normally
be generated.
- They can be used to round up/down to the next aligned value for both
integers and pointers without requiring two separate macros.
- In many projects the alignment operations are already wrapped in macros (e.g.
roundup2 and rounddown2 in FreeBSD), so by replacing the macro implementation
with a builtin call, we get improved diagnostics for many call-sites while
only having to change a few lines.
- Finally, the builtins also emit assume_aligned metadata when used on pointers.
This can improve code generation compared to the uintptr_t casts.
[1] In our CHERI compiler we have compilation mode where all pointers are
implemented as capabilities (essentially unforgeable 128-bit fat pointers).
In our original model, casts from uintptr_t (which is a 128-bit capability)
to an integer value returned the "offset" of the capability (i.e. the
difference between the virtual address and the base of the allocation).
This causes problems for cases such as checking the alignment: for example, the
expression `if ((uintptr_t)ptr & 63) == 0` is generally used to check if the
pointer is aligned to a multiple of 64 bytes. The problem with offsets is that
any pointer to the beginning of an allocation will have an offset of zero, so
this check always succeeds in that case (even if the address is not correctly
aligned). The same issues also exist when aligning up or down. Using the
alignment builtins ensures that the address is used instead of the offset. While
I have since changed the default C semantics to return the address instead of
the offset when casting, this offset compilation mode can still be used by
passing a command-line flag.
Reviewers: rsmith, aaron.ballman, theraven, fhahn, lebedev.ri, nlopes, aqjune
Reviewed By: aaron.ballman, lebedev.ri
Differential Revision: https://reviews.llvm.org/D71499
In common with most MVE immediate shift instructions, the left shift
takes an immediate in the range [0,n-1], while the right shift takes
one in the range [1,n]. I had absent-mindedly made them both the
latter.
While I'm here, I've added a set of regression tests checking both
ends of the immediate range for a representative sample of the
immediate shifts.
Summary:
The ACLE intrinsics with `gather_base` or `scatter_base` in the name
are wrappers on the MVE load/store instructions that take a vector of
base addresses and an immediate offset. The immediate offset can be up
to 127 times the alignment unit, and it can be positive or negative.
At the MC layer, we got that right. But in the Sema error checking for
the wrapping intrinsics, the offset was erroneously constrained to be
positive.
To fix this I've adjusted the `imm_mem7bit` class in the Tablegen that
defines the intrinsics. But that causes integer literals like
`0xfffffffffffffe04` to appear in the autogenerated calls to
`SemaBuiltinConstantArgRange`, which provokes a compiler warning
because that's out of the non-overflowing range of an `int64_t`. So
I've also tweaked `MveEmitter` to emit that as `-0x1fc` instead.
Updated the tests of the Sema checks themselves, and also adjusted a
random sample of the CodeGen tests to actually use negative offsets
and prove they get all the way through code generation without causing
a crash.
Reviewers: dmgreen, miyuki, MarkMurrayARM
Reviewed By: dmgreen
Subscribers: kristof.beyls, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72268
The current handling of the operators ||, && and ?: has a number of false
positive and false negative. The issues for operator || and && are:
1. We need to add sequencing regions for the LHS and RHS as is done for the
comma operator. Not doing so causes false positives in expressions like
`((a++, false) || (a++, false))` (from PR39779, see PR22197 for another
example).
2. In the current implementation when the evaluation of the LHS fails, the RHS
is added to a worklist to be processed later. This results in false negatives
in expressions like `(a && a++) + a`.
Fix these issues by introducing sequencing regions for the LHS and RHS, and by
not deferring the visitation of the RHS.
The issues with the ternary operator ?: are similar, with the added twist that
we should not warn on expressions like `(x ? y += 1 : y += 2)` since exactly
one of the 2nd and 3rd expression is going to be evaluated, but we should still
warn on expressions like `(x ? y += 1 : y += 2) = y`.
Differential Revision: https://reviews.llvm.org/D57747
Reviewed By: rsmith
These annotations will be used in an upcomming static analyzer check
that finds handle leaks, use after releases, and double releases.
Differential Revision: https://reviews.llvm.org/D70469
Summary:
This adds parsing of the qualifiers __ptr32, __ptr64, __sptr, and __uptr and
lowers them to the corresponding address space pointer for 32-bit and 64-bit pointers.
(32/64-bit pointers added in https://reviews.llvm.org/D69639)
A large part of this patch is making these pointers ignore the address space
when doing things like overloading and casting.
https://bugs.llvm.org/show_bug.cgi?id=42359
Reviewers: rnk, rsmith
Subscribers: jholewinski, jvesely, nhaehnle, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71039
The FP-classification builtins (__builtin_isfinite, etc) use variadic
packs in the definition file to mean an overload set. Because of that,
floats were converted to doubles, which is incorrect. There WAS a patch
to remove the cast after the fact.
THis patch switches these builtins to just be custom type checking,
calls the implicit conversions for the integer members, and makes sure
the correct L->R casts are put into place, then does type checking like
normal.
A future direction (that wouldn't be NFC) would consider making
conversions for the floating point parameter legal.
Note: The initial patch for this missed that certain systems need to
still convert half to float, since they dont' support that type.
This covers:
* usual arithmetic conversions (comparisons, arithmetic, conditionals)
between different enumeration types
* usual arithmetic conversions between enums and floating-point types
* comparisons between two operands of array type
The deprecation warnings are on-by-default (in C++20 compilations); it
seems likely that these forms will become ill-formed in C++23, so
warning on them now by default seems wise.
For the first two bullets, off-by-default warnings were also added for
all the cases where we didn't already have warnings (covering language
modes prior to C++20). These warnings are in subgroups of the existing
-Wenum-conversion (except that the first case is not warned on if either
enumeration type is anonymous, consistent with our existing
-Wenum-conversion warnings).
This reverts commit b1e542f302.
The original 'hack' didn't chop out fp-16 to double conversions, so
systems that use FP16ConversionIntrinsics end up in IR-CodeGen with an
i16 type isntead of a float type (like PPC64-BE). The bots noticed
this.
Reverting until I figure out how to fix this
The FP-classification builtins (__builtin_isfinite, etc) use variadic
packs in the definition file to mean an overload set. Because of that,
floats were converted to doubles, which is incorrect. There WAS a patch
to remove the cast after the fact.
THis patch switches these builtins to just be custom type checking,
calls the implicit conversions for the integer members, and makes sure
the correct L->R casts are put into place, then does type checking like
normal.
A future direction (that wouldn't be NFC) would consider making
conversions for the floating point parameter legal.
Now Clang does not check that features required by built-in functions
are enabled. That causes errors in the backend reported in PR44018.
This patch fixes this bug by checking that required features
are enabled.
This should fix PR44018.
Differential Revision: https://reviews.llvm.org/D70808
References need somewhat special treatment. While copying a gsl::Pointer
will propagate the points-to set, creating an object from a reference
often behaves more like a dereference operation.
Differential Revision: https://reviews.llvm.org/D70755
Current EvalInfo ctor causes EnableNewConstInterp to be true even though
it is supposed to be false on MSVC 2017. This is because a virtual function
getLangOpts() is called in member initializer lists, whereas on MSVC
member ctors are called before function virtual function pointers are
initialized.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D70729
Summary:
As noted in PR, we have a poor test coverage for this warning. I think macro support was just overlooked. GCC warns in these cases.
Clang missed a real bug in the code I am working with, GCC caught it.
Reviewers: aaron.ballman
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D70624
This fixes an assertion in Sema::CreateBuiltinBinOp that fails when one
of the vector operand's element type is a typedef of __fp16.
rdar://problem/55983556
Summary:
A user may want to use freestanding mode with the standard "main" entry
point. It's not useful to warn about a missing prototype as it's not
typical to have a prototype for "main".
Reviewers: efriedma, aaron.ballman
Reviewed By: aaron.ballman
Subscribers: aaron.ballman, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D70588
We seem to have been gradually growing support for atomic min/max operations
(exposing longstanding IR atomicrmw instructions). But until now there have
been gaps in the expected intrinsics. This adds support for the C11-style
intrinsics (i.e. taking _Atomic, rather than individually blessed by C11
standard), and the variants that return the new value instead of the original
one.
That way, people won't be misled by trying one form and it not working, and the
front-end is more friendly to people using _Atomic types, as we recommend.
Some clients of this function want to know about any expression that is known
to produce a 0/1 value, and others care about expressions that are semantically
boolean.
This fixes a -Wswitch-bool regression I introduced in 8bfb353bb3, pointed out
by Chris Hamilton!
Summary:
Semantically they're the same thing, and it's important when the underlying
struct is anonymous.
There doesn't seem to be a problem attaching the same comment to multiple things
as it already happens with `/** doc */ int a, b;`
This affects an Index test but the results look better (name present, USR points
to the typedef).
Fixes https://github.com/clangd/clangd/issues/189
Reviewers: kadircet, lh123
Subscribers: ilya-biryukov, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D70203
Provides support for using r6-r11 as globally scoped
register variables. This requires a -ffixed-rN flag
in order to reserve rN against general allocation.
If for a given GRV declaration the corresponding flag
is not found, or the the register in question is the
target's FP, we fail with a diagnostic.
Differential Revision: https://reviews.llvm.org/D68862
This adds the `vgetq_lane` and `vsetq_lane` families, to copy between
a scalar and a specified lane of a vector.
One of the new `vgetq_lane` intrinsics returns a `float16_t`, which
causes a compile error if `%clang_cc1` doesn't get the option
`-fallow-half-arguments-and-returns`. The driver passes that option to
cc1 already, but I've had to edit all the explicit cc1 command lines
in the existing MVE intrinsics tests.
A couple of fixes are included for the code I wrote up front in
MveEmitter to support lane-index immediates (and which nothing has
tested until now): the type was wrong (`uint32_t` instead of `int`)
and the range was off by one.
I've also added a method of bypassing the default promotion to `i32`
that is done by the MveEmitter code generation: it's sensible to
promote short scalars like `i16` to `i32` if they're going to be
passed to custom IR intrinsics representing a machine instruction
operating on GPRs, but not if they're going to be passed to standard
IR operations like `insertelement` which expect the exact type.
Reviewers: ostannard, MarkMurrayARM, dmgreen
Reviewed By: dmgreen
Subscribers: kristof.beyls, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D70188
This patch is a follow-up for commit 4e2ce228ae
[BPF] Add preserve_access_index attribute for record definition
to restrict attribute for C only. A new test case is added
to check for this restriction.
Additional code polishing is done based on
Aaron Ballman's suggestion in https://reviews.llvm.org/D69759/new/.
Differential Revision: https://reviews.llvm.org/D70257
This is a resubmission for the previous reverted commit
9434360401 with the same subject. This commit fixed the
segfault issue and addressed additional review comments.
This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
struct s { ... } __attribute__((preserve_access_index));
union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.
The attribute has no effect if -g is not specified.
When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
__builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.
The following is an example to illustrate the usage:
-bash-4.4$ cat t.c
#define __reloc__ __attribute__((preserve_access_index))
struct s1 {
int c;
} __reloc__;
struct s2 {
union {
struct s1 b[3];
};
} __reloc__;
struct s3 {
struct s2 a;
} __reloc__;
int test(struct s3 *arg) {
return arg->a.b[2].c;
}
-bash-4.4$ clang -target bpf -g -S -O2 t.c
A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.
forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.
Differential Revision: https://reviews.llvm.org/D69759
Some warnings in -Wtautological-compare subgroups are DefaultIgnore.
Adding this group to -Wmost, which is part of -Wall, will aid in their
discoverability.
Differential Revision: https://reviews.llvm.org/D69292
This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
struct s { ... } __attribute__((preserve_access_index));
union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.
The attribute has no effect if -g is not specified.
When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
__builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.
The following is an example to illustrate the usage:
-bash-4.4$ cat t.c
#define __reloc__ __attribute__((preserve_access_index))
struct s1 {
int c;
} __reloc__;
struct s2 {
union {
struct s1 b[3];
};
} __reloc__;
struct s3 {
struct s2 a;
} __reloc__;
int test(struct s3 *arg) {
return arg->a.b[2].c;
}
-bash-4.4$ clang -target bpf -g -S -O2 t.c
A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.
forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.
Differential Revision: https://reviews.llvm.org/D69759
While here, wordsmith the error a bit. Now clang says:
error: filter expression has non-integral type 'Foo'
Fixes PR43779
Reviewers: amccarth
Differential Revision: https://reviews.llvm.org/D69969
This patch adds two new families of intrinsics, both of which are
memory accesses taking a vector of locations to load from / store to.
The vldrq_gather_base / vstrq_scatter_base intrinsics take a vector of
base addresses, and an immediate offset to be added consistently to
each one. vldrq_gather_offset / vstrq_scatter_offset take a scalar
base address, and a vector of offsets to add to it. The
'shifted_offset' variants also multiply each offset by the element
size type, so that the vector is effectively of array indices.
At the IR level, these operations are represented by a single set of
four IR intrinsics: {gather,scatter} × {base,offset}. The other
details (signed/unsigned, shift, and memory element size as opposed to
vector element size) are all specified by IR intrinsic polymorphism
and immediate operands, because that made the selection job easier
than making a huge family of similarly named intrinsics.
I considered using the standard IR representations such as
llvm.masked.gather, but they're not a good fit. In order to use
llvm.masked.gather to represent a gather_offset load with element size
smaller than a pointer, you'd have to expand the <8 x i16> vector of
offsets into an <8 x i16*> vector of pointers, which would be split up
during legalization, so you'd spend most of your time undoing the mess
it had made. Also, ISel support for llvm.masked.gather would be easy
enough in a trivial way (you can expand it into a gather-base load
with a zero immediate offset), but instruction-selecting lots of
fiddly idioms back into all the _other_ MVE load instructions would be
much more work. So I think dedicated IR intrinsics are the more
sensible approach, at least for the moment.
On the clang tablegen side, I've added two new features to the
Tablegen source accepted by MveEmitter: a 'CopyKind' type node for
defining a type that varies with the parameter type (it lets you ask
for an unsigned integer type of the same width as the parameter), and
an 'unsignedflag' value node for passing an immediate IR operand which
is 0 for a signed integer type or 1 for an unsigned one. That lets me
write each kind of intrinsic just once and get all its subtypes and
immediate arguments generated automatically.
Also I've tweaked the handling of pointer-typed values in the code
generation part of MveEmitter: they're generated as Address rather
than Value (i.e. including an alignment) so that they can be given to
the ordinary IR load and store operations, but I'd omitted the code to
convert them back to Value when they're going to be used as an
argument to an IR intrinsic.
On the MC side, I've enhanced MVEVectorVTInfo so that it can tell you
not only the full assembly-language suffix for a given vector type
(like 's32' or 'u16') but also the numeric-only one used by store
instructions (just '32' or '16').
Reviewers: dmgreen
Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D69791
Summary:
This is a follow up on https://reviews.llvm.org/D61634
This patch is simpler and only adds the no_builtin attribute.
Reviewers: tejohnson, courbet, theraven, t.p.northover, jdoerfert
Subscribers: mgrang, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D68028
This is a re-submit after it got reverted in https://reviews.llvm.org/rGbd8791610948 since the breakage doesn't seem to come from this patch.
Summary:
This is a follow up on https://reviews.llvm.org/D61634
This patch is simpler and only adds the no_builtin attribute.
Reviewers: tejohnson, courbet, theraven, t.p.northover, jdoerfert
Subscribers: mgrang, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D68028
See also: D67515
- For the given call expression we would end up repeatedly
trying to transform the same expression over and over again
- Fix is to keep the old TransformCache when checking for ambiguity
Differential Revision: https://reviews.llvm.org/D69060
This allows you to declare a function with a name of your choice (say
`foo`), but have clang treat it as if it were a builtin function (say
`__builtin_foo`), by writing
static __inline__ __attribute__((__clang_arm_mve_alias(__builtin_foo)))
int foo(args);
I'm intending to use this for the ACLE intrinsics for MVE, which have
to be polymorphic on their argument types and also need to be
implemented by builtins. To avoid having to implement the polymorphism
with several layers of nested _Generic and make error reporting
hideous, I want to make all the user-facing intrinsics correspond
directly to clang builtins, so that after clang resolves
__attribute__((overloadable)) polymorphism it's already holding the
right BuiltinID for the intrinsic it selected.
However, this commit itself just introduces the new attribute, and
doesn't use it for anything.
To avoid unanticipated side effects if this attribute is used to make
aliases to other builtins, there's a restriction mechanism: only
(BuiltinID, alias) pairs that are approved by the function
ArmMveAliasValid() will be permitted. At present, that function
doesn't permit anything, because the Tablegen that will generate its
list of valid pairs isn't yet implemented. So the only test of this
facility is one that checks that an unapproved builtin _can't_ be
aliased.
Reviewers: dmgreen, miyuki, ostannard
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67159
Taking a value and the bitwise-or it with a non-zero constant will always
result in a non-zero value. In a boolean context, this is always true.
if (x | 0x4) {} // always true, intended '&'
This patch creates a new warning group -Wtautological-bitwise-compare for this
warning. It also moves in the existing tautological bitwise comparisons into
this group. A few other changes were needed to the CFGBuilder so that all bool
contexts would be checked. The warnings in -Wtautological-bitwise-compare will
be off by default due to using the CFG.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=42666
Differential Revision: https://reviews.llvm.org/D66046
llvm-svn: 375318
__builtin_assume_aligned takes a size_t which is a 32 bit int on
hexagon. Thus, the constant gets converted to a 32 bit value, resulting
in 0 not being a power of 2. This patch changes the constant being
passed to 2**30 so that it fails, but doesnt exceed 30 bits.
llvm-svn: 374569
The behavior from the original patch has changed, since we're no longer
allowing LLVM to just ignore the alignment. Instead, we're just
assuming the maximum possible alignment.
Differential Revision: https://reviews.llvm.org/D68824
llvm-svn: 374562
The test fails on Windows, with
error: 'warning' diagnostics expected but not seen:
File builtin-assume-aligned.c Line 62: requested alignment
must be 268435456 bytes or smaller; assumption ignored
error: 'warning' diagnostics seen but not expected:
File builtin-assume-aligned.c Line 62: requested alignment
must be 8192 bytes or smaller; assumption ignored
llvm-svn: 374456
Code to handle __builtin_assume_aligned was allowing larger values, but
would convert this to unsigned along the way. This patch removes the
EmitAssumeAligned overloads that take unsigned to do away with this
problem.
Additionally, it adds a warning that values greater than 1 <<29 are
ignored by LLVM.
Differential Revision: https://reviews.llvm.org/D68824
llvm-svn: 374450
I noticed that compiling on Windows with -fno-ms-compatibility had the
side effect of defining __GNUC__, along with __GNUG__, __GXX_RTTI__, and
a number of other macros for GCC compatibility. This is undesirable and
causes Chromium to do things like mix __attribute__ and __declspec,
which doesn't work. We should have a positive language option to enable
GCC compatibility features so that we can experiment with
-fno-ms-compatibility on Windows. This change adds -fgnuc-version= to be
that option.
My issue aside, users have, for a long time, reported that __GNUC__
doesn't match their expectations in one way or another. We have
encouraged users to migrate code away from this macro, but new code
continues to be written assuming a GCC-only environment. There's really
nothing we can do to stop that. By adding this flag, we can allow them
to choose their own adventure with __GNUC__.
This overlaps a bit with the "GNUMode" language option from -std=gnu*.
The gnu language mode tends to enable non-conforming behaviors that we'd
rather not enable by default, but the we want to set things like
__GXX_RTTI__ by default, so I've kept these separate.
Helps address PR42817
Reviewed By: hans, nickdesaulniers, MaskRay
Differential Revision: https://reviews.llvm.org/D68055
llvm-svn: 374449
Summary:
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
up generating lots of false-positives.
Moreover, due to the ability of character pointers to alias non-character
pointers, the strict aliasing violations that would generally be implied by the
calculations caught by the warning (if the calculation itself is in fact
correct) do not apply here, and so although the length calculation may be
wrong, that is the only possible issue.
Reviewers: rsmith, xbolva00, thakis
Reviewed By: xbolva00, thakis
Subscribers: thakis, lebedev.ri, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D68526
llvm-svn: 374035
The warnings now in -Wformat-type-confusion don't align with how we interpret
'pedantic' in clang, and don't belong in -pedantic.
Differential revision: https://reviews.llvm.org/D67775
llvm-svn: 373774
Extracted from D63082. GCC has this warning under -Wint-in-bool-context, but as noted in the D63082's review, we should put it under TautologicalConstantCompare.
llvm-svn: 372531
Commit c15aa241f8 ("[CLANG][BPF] change __builtin_preserve_access_index()
signature") changed the builtin function signature to
PointerT __builtin_preserve_access_index(PointerT ptr)
with a pointer type as the argument/return type, where argument and
return types must be the same.
There is really no reason for this constraint. The builtin just
presented a code region so that IR builtins
__builtin_{array, struct, union}_preserve_access_index
can be applied.
This patch removed the pointer type restriction to permit any
argument type as long as it is permitted by the compiler.
Differential Revision: https://reviews.llvm.org/D67883
llvm-svn: 372516
-Wtautological-overlap-compare and self-comparison from -Wtautological-compare
relay on detecting the same operand in different locations. Previously, each
warning had it's own operand checker. Now, both are merged together into
one function that each can call. The function also now looks through member
access and array accesses.
Differential Revision: https://reviews.llvm.org/D66045
llvm-svn: 372453
Allow this warning to detect a larger number of constant values, including
negative numbers, and handle non-int types better.
Differential Revision: https://reviews.llvm.org/D66044
llvm-svn: 372448
The clang intrinsic __builtin_preserve_access_index() currently
has signature:
const void * __builtin_preserve_access_index(const void * ptr)
This may cause compiler warning when:
- parameter type is "volatile void *" or "const volatile void *", or
- the assign-to type of the intrinsic does not have "const" qualifier.
Further, this signature does not allow dereference of the
builtin result pointer as it is a "const void *" type, which
adds extra step for the user to do type casting.
Let us change the signature to:
PointerT __builtin_preserve_access_index(PointerT ptr)
such that the result and argument types are the same.
With this, directly dereferencing the builtin return value
becomes possible.
Differential Revision: https://reviews.llvm.org/D67734
llvm-svn: 372294
Also, add a diagnostic under -Wformat for printing a boolean value as a
character.
rdar://54579473
Differential revision: https://reviews.llvm.org/D66856
llvm-svn: 372247
Also, add a diagnostic group, -Wobjc-signed-char-bool, to control all these
related diagnostics.
rdar://51954400
Differential revision: https://reviews.llvm.org/D67559
llvm-svn: 372183
Summary:
This fixes a bug introduced in D62648, where Clang could infinite loop
if it became stuck on a single TypoCorrection when it was supposed to
be testing ambiguous corrections. Although not a common case, it could
happen if there are multiple possible corrections with the same edit
distance.
The fix is simply to wipe the TypoExpr from the `TransformCache` so that
the call to `TransformTypoExpr` doesn't use the `CachedEntry`.
Reviewers: rsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67515
llvm-svn: 371859
levels:
-- none: no lax vector conversions [new GCC default]
-- integer: only conversions between integer vectors [old GCC default]
-- all: all conversions between same-size vectors [Clang default]
For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)
Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.
This reinstates r371805, reverted in r371813, with an additional fix for
lldb.
llvm-svn: 371817
levels:
-- none: no lax vector conversions [new GCC default]
-- integer: only conversions between integer vectors [old GCC default]
-- all: all conversions between same-size vectors [Clang default]
For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)
Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.
llvm-svn: 371805
Summary:
The first NFC change is to replace a getCXXABI().isMicrosoft() check
with getTriple().isWindowsMSVCEnvironment(). This code takes effect in
non-C++ compilations, so it doesn't make sense to check the C++ ABI. In
the MS ABI, enums are always considered to be "complete" because the
underlying type of an unfixed enum will always be 'int'. This behavior
was moved from -fms-compatibility to MS ABI back in r249656.
The second change is functional, and it downgrades an error to a warning
when the MS ABI is used rather than only under -fms-compatibility. The
reasoning is that it's unreasonable for the following code to reject the
following code for all MS ABI targets with -fno-ms-compatibility:
enum Foo { Foo_Val = 0xDEADBEEF };
This is valid code for any other target, but in the MS ABI, Foo_Val just
happens to be negative. With this change, clang emits a
-Wmicrosoft-enum-value warning on this code, but compiles it without
error.
Fixes PR38478
Reviewers: hans, rsmith, STL_MSFT
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67304
llvm-svn: 371581
constant-folding mode regardless of the original evaluation mode.
In order for this to be correct, we need to track whether we're checking
for a potential constant expression or checking for undefined behavior
separately from the evaluation mode enum, since we don't want to clobber
those states when entering constant-folding mode.
llvm-svn: 371557
Current for SAE instructions we only allow _MM_FROUND_CUR_DIRECTION(bit 2) or _MM_FROUND_NO_EXC(bit 3) to be used as the immediate passed to the inrinsics. But these instructions don't perform rounding so _MM_FROUND_CUR_DIRECTION is just sort of a default placeholder when you don't want to suppress exceptions. Using _MM_FROUND_NO_EXC by itself is really bit equivalent to (_MM_FROUND_NO_EXC | _MM_FROUND_TO_NEAREST_INT) since _MM_FROUND_TO_NEAREST_INT is 0. Since we aren't rounding on these instructions we should also accept (_MM_FROUND_CUR_DIRECTION | _MM_FROUND_NO_EXC) as equivalent to (_MM_FROUND_NO_EXC). icc allows this, but gcc does not.
Differential Revision: https://reviews.llvm.org/D67289
llvm-svn: 371430
Previously, -Wsizeof-pointer-div failed to catch:
const int *r;
sizeof(r) / sizeof(int);
Now fixed.
Also introduced -Wsizeof-array-div which catches bugs like:
sizeof(r) / sizeof(short);
(Array element type does not match type of sizeof operand).
llvm-svn: 371222
A number of inline assembly constraints are currently supported by LLVM, but rejected as invalid by Clang:
Target independent constraints:
s: An integer constant, but allowing only relocatable values
ARM specific constraints:
j: An immediate integer between 0 and 65535 (valid for MOVW)
x: A 32, 64, or 128-bit floating-point/SIMD register: s0-s15, d0-d7, or q0-q3
N: An immediate integer between 0 and 31 (Thumb1 only)
O: An immediate integer which is a multiple of 4 between -508 and 508. (Thumb1 only)
This patch adds support to Clang for the missing constraints along with some checks to ensure that the constraints are used with the correct target and Thumb mode, and that immediates are within valid ranges (at least where possible). The constraints are already implemented in LLVM, but just a couple of minor corrections to checks (V8M Baseline includes MOVW so should work with 'j', 'N' and 'O' shouldn't be valid in Thumb2) so that Clang and LLVM are in line with each other and the documentation.
Differential Revision: https://reviews.llvm.org/D65863
Change-Id: I18076619e319bac35fbb60f590c069145c9d9a0a
llvm-svn: 371079
Summary:
The assertion happens when compiling with -Wdocumentation with variable declaration to a typedefed function pointer. I not too familiar with the ObjC syntax but first two tests assert without this patch.
Fixes https://bugs.llvm.org/show_bug.cgi?id=42844
Reviewers: gribozavr
Reviewed By: gribozavr
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D66706
llvm-svn: 370677
initializers.
This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:
* We continue to permit the full breadth of C99 designated initializers
in C++, with the exception that we disallow a partial overwrite of an
initializer with a non-trivially-destructible type. (Full overwrite
is OK, because we won't run the first initializer at all.)
* The C99 extensions are disallowed in SFINAE contexts and during
overload resolution, where they could change the meaning of valid
programs.
* C++20 disallows reordering of initializers. We only check for that for
the simple cases that the C++20 rules permit (designators of the form
'.field_name =' and continue to allow reordering in other cases).
It would be nice to improve this behavior in future.
* All C99 designated initializer extensions produce a warning by
default in C++20 mode. People are going to learn the C++ rules based
on what Clang diagnoses, so it's important we diagnose these properly
by default.
* In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
so still diagnose C99 extensions as described above. We continue to
accept designated C++20-compatible initializers in C++ <= 17 silently
by default (but naturally still reject under -pedantic-errors).
This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.
This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.
Differential Revision: https://reviews.llvm.org/D59754
llvm-svn: 370544
list, rather than recursively checking multiple lists in C.
This simplification is in preparation for making InitListChecker
maintain more state that's specific to the explicit initializer list,
particularly when handling designated initialization.
llvm-svn: 370418
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.
Fixes a false positive warning "control may reach end of non-void function".
llvm-svn: 370406
Based on @davezarzycki remarks in D64696 improved the wording of the warning
message.
Differential Revision: https://reviews.llvm.org/D66700
Patch by Mark de Wever.
llvm-svn: 369873
Summary:
As Typo Resolution can create new TypoExprs while resolving typos,
it is necessary to recurse through the expression to search for more
typos.
This should fix the assertion failure in `clang::Sema::~Sema()`:
`DelayedTypos.empty() && "Uncorrected typos!"`
Notes:
- In case some TypoExprs are created but thrown away, Sema
now has a Vector that is used to keep track of newly created
typos.
- For expressions with multiple typos, we only give suggestions
if we are able to resolve all typos in the expression
- This patch is similar to D37521 except that it does not eagerly
commit to a correction for the first typo in the expression.
Instead, it will search for corrections which fix all of the
typos in the expression.
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D62648
llvm-svn: 369427
...so that at least a preceding \param etc. that lacks a description gets a
-Wdocumentation warning (instead of erroneously treating the \retval ... text as
its paragraph).
Differential Revision: https://reviews.llvm.org/D66350
llvm-svn: 369345
This gives library implementers a way to use standards-based attributes that do not conflict with user-defined macros of the same name. Attributes in C2x require this behavior normatively (C2x 6.7.11p4), but there's no reason to not have the same behavior in C++, especially given that such attributes may be used by a C library consumed by a C++ compilation.
llvm-svn: 369033
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:
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
A buildbot got angry about this new test, with error messages like:
warn-nullchar-nullptr.c Line 16: use of undeclared identifier 'u'
It looks like this `u'c'` syntax was introduced in C11; I'm guessing
some bots may default to something before that. Let's see if explicitly
specifying the standard version makes it happy...
llvm-svn: 367947
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
Summary:
It warns for for comments like
/** \pre \em */
where \em has no argument
This warning is enabled with the -Wdocumentation option.
Reviewers: gribozavr, rsmith
Reviewed By: gribozavr
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64696
Patch by Mark de Wever.
llvm-svn: 367809
Summary:
The -Wparentheses warnings are enabled by default in clang but they are under
-Wall in gcc (gcc/c-family/c.opt). Some of the operator precedence warnings are
oftentimes criticized as noise (clang: default; gcc: -Wall). If a warning is
very controversial, it is probably not a good idea to enable it by default.
This patch disables the rather annoying ones:
-Wbitwise-op-parentheses, e.g. i & i | i
-Wlogical-op-parentheses, e.g. i && i || i
After this change:
```
* = enabled by default
-Wall
-Wparentheses
-Wlogical-op-parentheses
-Wlogical-not-parentheses*
-Wbitwise-op-parentheses
-Wshift-op-parentheses*
-Woverloaded-shift-op-parentheses*
-Wparentheses-equality*
-Wdangling-else*
```
-Woverloaded-shift-op-parentheses is typically followed by overload
resolution failure. We can instead improve the error message, and
probably delete -Woverloaded-shift-op-parentheses in the future. Keep it
for now because it gives some diagnostics.
Reviewers: akyrtzi, jyknight, rtrieu, rsmith, aaron.ballman
Reviewed By: aaron.ballman
Subscribers: dexonsmith, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D65192
llvm-svn: 367690
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
This adds support for parsing/emitting in IR the floating-point RISC-V
registers in inline assembly clobber lists.
Differential Revision: https://reviews.llvm.org/D64737
llvm-svn: 367399
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
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
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
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
The original commit is r366076. It is temporarily reverted (r366155)
due to test failure. This resubmit makes test more robust by accepting
regex instead of hardcoded names/references in several places.
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: 366231
Summary:
D28148 relaxed some checks for assigning { 0 } to a structure for all C
standards, but it failed to handle structures with non-integer
subobjects. Relax -Wmissing-braces checks for such structures, and add
some additional tests.
This fixes PR39931.
Patch By: al3xtjames
Reviewed By: Lekensteyn
Differential Revision: https://reviews.llvm.org/D61838
llvm-svn: 366163
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
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
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
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
error: 'error' diagnostics expected but not seen:
File /vol/llvm/src/clang/local/test/Sema/wchar.c Line 22: initializing wide char array with non-wide string literal
error: 'error' diagnostics seen but not expected:
File /vol/llvm/src/clang/local/test/Sema/wchar.c Line 20: array initializer must be an initializer list
File /vol/llvm/src/clang/local/test/Sema/wchar.c Line 22: array initializer must be an initializer list
It turns out the definition is wrong, as can be seen in GCC's gcc/config/sol2.h:
/* wchar_t is called differently in <wchar.h> for 32 and 64-bit
compilations. This is called for by SCD 2.4.1, p. 6-83, Figure 6-65
(32-bit) and p. 6P-10, Figure 6.38 (64-bit). */
#undef WCHAR_TYPE
#define WCHAR_TYPE (TARGET_64BIT ? "int" : "long int")
The following patch implements this, and at the same time corrects the wint_t
definition which is the same:
/* Same for wint_t. See SCD 2.4.1, p. 6-83, Figure 6-66 (32-bit). There's
no corresponding 64-bit definition, but this is what Solaris 8
<iso/wchar_iso.h> uses. */
#undef WINT_TYPE
#define WINT_TYPE (TARGET_64BIT ? "int" : "long int")
Clang :: Preprocessor/wchar_t.c and Clang :: Sema/format-strings.c need to
be adjusted to account for that.
Tested on i386-pc-solaris2.11, x86_64-pc-solaris2.11, and x86_64-pc-linux-gnu.
Differential Revision: https://reviews.llvm.org/D62944
llvm-svn: 363612
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
Seems like a logical extension to me - and of interest because it might
help reduce the debug info size of libc++ by applying this attribute to
type traits that have a disproportionate debug info cost compared to the
benefit (& possibly harm/confusion) they cause users.
llvm-svn: 362856
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
Add a test for tracking PR41027 (8.0 regression breaking assembly code
relying on __builtin_constant_p() to identify compile-time constants).
Mark it as expected to fail everywhere.
Differential Revision: https://reviews.llvm.org/D60728
llvm-svn: 362587
Syntax:
asm [volatile] goto ( AssemblerTemplate
:
: InputOperands
: Clobbers
: GotoLabels)
https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html
New llvm IR is "callbr" for inline asm goto instead "call" for inline asm
For:
asm goto("testl %0, %0; jne %l1;" :: "r"(cond)::label_true, loop);
IR:
callbr void asm sideeffect "testl $0, $0; jne ${1:l};", "r,X,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@foo, %label_true), i8* blockaddress(@foo, %loop)) #1
to label %asm.fallthrough [label %label_true, label %loop], !srcloc !3
asm.fallthrough:
Compiler need to generate:
1> a dummy constarint 'X' for each label.
2> an unique fallthrough label for each asm goto stmt " asm.fallthrough%number".
Diagnostic
1> duplicate asm operand name are used in output, input and label.
2> goto out of scope.
llvm-svn: 362045
These don't support embedded rounding so we shouldn't be setting HasRC. That way we only
allow current direction and suppress all exceptions.
llvm-svn: 361897
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
declaration.
It should emit _only_ an implicit-function-declaration warning, not
both of them.
Differential Revision: https://reviews.llvm.org/D59711
llvm-svn: 360084
where either the modification or the other access is unreachable.
This reverts r359984 (which reverted r359962). The bug in clang-tidy's
test suite exposed by the original commit was fixed in r360009.
llvm-svn: 360010
__builtin_constant_p.
If the operand of __builtin_constant_p is not constant and has
side-effects, then code controlled by a branch on it is unreachable and
we should not emit runtime behavior warnings in such code.
llvm-svn: 359844
If an address_space attribute is defined in a macro, print the macro instead
when diagnosing a warning or error for incompatible pointers with different
address_spaces.
We allow this for all attributes (not just address_space), and for multiple
attributes declared in the same macro.
Differential Revision: https://reviews.llvm.org/D51329
llvm-svn: 359826
Summary:
GCC's -Wtype-limits (part of -Wextra):
Warn if a comparison is always true or always false due to the limited range of the data type
Reviewers: rsmith, aaron.ballman, lebedev.ri, thakis
Reviewed By: rsmith
Subscribers: lebedev.ri, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58841
llvm-svn: 359516
This provides intrinsics support for Memory Tagging Extension (MTE),
which was introduced with the Armv8.5-a architecture.
These intrinsics are available when __ARM_FEATURE_MEMORY_TAGGING is defined.
Each intrinsic is described in detail in the ACLE Q1 2019 documentation:
https://developer.arm.com/docs/101028/latest
Reviewed By: Tim Nortover, David Spickett
Differential Revision: https://reviews.llvm.org/D60485
llvm-svn: 359348
Summary:
This patch implements `__builtin_is_constant_evaluated` as specifier by [P0595R2](https://wg21.link/p0595r2). It is built on the back of Bill Wendling's work for `__builtin_constant_p()`.
More tests to come, but early feedback is appreciated.
I plan to implement warnings for common mis-usages like those belowe in a following patch:
```
void foo(int x) {
if constexpr (std::is_constant_evaluated())) { // condition is always `true`. Should use plain `if` instead.
foo_constexpr(x);
} else {
foo_runtime(x);
}
}
```
Reviewers: rsmith, MaskRay, bruno, void
Reviewed By: rsmith
Subscribers: dexonsmith, zoecarver, fdeazeve, kristina, cfe-commits
Differential Revision: https://reviews.llvm.org/D55500
llvm-svn: 359067
Without this patch, APSInt inherits APInt::isNegative, which merely
checks the sign bit without regard to whether the type is actually
signed. isNonNegative and isStrictlyPositive call isNegative and so
are also affected.
This patch adjusts APSInt to override isNegative, isNonNegative, and
isStrictlyPositive with implementations that consider whether the type
is signed.
A large set of Clang OpenMP tests are affected. Without this patch,
these tests assume that `true` is not a valid argument for clauses
like `collapse`. Indeed, `true` fails APInt::isStrictlyPositive but
not APSInt::isStrictlyPositive. This patch adjusts those tests to
assume `true` should be accepted.
This patch also adds tests revealing various other similar fixes due
to APSInt::isNegative calls in Clang's ExprConstant.cpp and
SemaExpr.cpp: `++` and `--` overflow in `constexpr`, evaluated object
size based on `alloc_size`, `<<` and `>>` shift count validation, and
OpenMP array section validation.
Reviewed By: lebedev.ri, ABataev, hfinkel
Differential Revision: https://reviews.llvm.org/D59712
llvm-svn: 359012
We want to make objc_nonlazy_class apply to implementations, but ran into this.
There doesn't seem to be any reason that this isn't supported.
Differential revision: https://reviews.llvm.org/D60542
llvm-svn: 358200
This fixes a false positive on the following, where st is configured to have
different sizes based on some preprocessor logic:
if (sizeof(buf) == sizeof(*st))
memcpy(&buf, st, sizeof(*st));
llvm-svn: 357041
After https://reviews.llvm.org/rL355317 we noticed that quite a decent
amount of code redeclares builtins (memcpy in particular, I believe
reduced from an MSVC header) with a calling convention specified.
This gets particularly troublesome when the user specifies a new
'default' calling convention on the command line.
When looking to add a diagnostic for this case, it was noticed that we
had 3 other diagnostics that differed only slightly. This patch ALSO
unifies those under a 'select'. Unfortunately, the order of words in
ONE of these diagnostics was reversed ("'thiscall' calling convention"
vs "calling convention 'thiscall'"), so this patch also standardizes on
the former.
Differential Revision: https://reviews.llvm.org/D59560
Change-Id: I79f99fe7c2301640755ffdd774b46eb44526bb22
llvm-svn: 356663
Before this commit, we emit unavailable errors for calls to functions during
overload resolution, and for references to all other declarations in
DiagnoseUseOfDecl. The early checks during overload resolution aren't as good as
the DiagnoseAvailabilityOfDecl based checks, as they error on the code from
PR40991. This commit fixes this by removing the early checking.
llvm.org/PR40991
rdar://48564179
Differential revision: https://reviews.llvm.org/D59394
llvm-svn: 356599
The attribute pass_dynamic_object_size(n) behaves exactly like
pass_object_size(n), but instead of evaluating __builtin_object_size on calls,
it evaluates __builtin_dynamic_object_size, which has the potential to produce
runtime code when the object size can't be determined statically.
Differential revision: https://reviews.llvm.org/D58757
llvm-svn: 356515
Summary:
Similar to D56967, we add the existing diag::note_locked_here to tell
the user where we saw the locking that isn't matched correctly.
Reviewers: aaron.ballman, delesley
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59455
llvm-svn: 356427
These diagnose overflowing calls to subset of fortifiable functions. Some
functions, like sprintf or strcpy aren't supported right not, but we should
probably support these in the future. We previously supported this kind of
functionality with -Wbuiltin-memcpy-chk-size, but that diagnostic doesn't work
with _FORTIFY implementations that use wrapper functions. Also unlike that
diagnostic, we emit these warnings regardless of whether _FORTIFY_SOURCE is
actually enabled, which is nice for programs that don't enable the runtime
checks.
Why not just use diagnose_if, like Bionic does? We can get better diagnostics in
the compiler (i.e. mention the sizes), and we have the potential to diagnose
sprintf and strcpy which is impossible with diagnose_if (at least, in languages
that don't support C++14 constexpr). This approach also saves standard libraries
from having to add diagnose_if.
rdar://48006655
Differential revision: https://reviews.llvm.org/D58797
llvm-svn: 356397
Fangrui Song