The layout and the size of an ObjC interface can change after its
corresponding implementation is parsed when synthesized ivars or ivars
declared in categories are added to the interface's list of ivars. This
can cause clang to mis-compile if the optimization that emits fixed
offsets for ivars (see 923ddf65f4e21ec67018cf56e823895de18d83bc) uses an
ObjC class layout that is outdated and no longer reflects the current
state of the class.
For example, when compiling `constant-non-fragile-ivar-offset.m`, clang
emits 20 instead of 24 as the offset for `IntermediateClass2Property` as
the class layout for `SuperClass2`, which is created when the
implementation of IntermediateClass3 is parsed, is outdated when the
implementation of `IntermediateClass2` is parsed.
This commit invalidates the stale layout information of the class and
its subclasses if new ivars are added to the interface.
With this change, we can also stop using ObjC implementation decls as
the key to retrieve ObjC class layouts information as the layout
retrieved using the ObjC interface as the key will always be up to date.
rdar://139531391
As part of the "RemoveDIs" work to eliminate debug intrinsics, we're
replacing methods that use Instruction*'s as positions with iterators. The
call-sites updated in this patch are those where the dyn_cast_or_null cast
utility doesn't compose well with iterator insertion. It can distinguish
between nullptr and a "present" (non-null) Instruction pointer, but not
between a legal and illegal instruction iterator. This can lead to
end-iterator dereferences and thus crashes.
We can improve this in the future (as parent-pointers can now be accessed
from ilist nodes), but for the moment, add explicit tests for end()
iterators at the five call sites affected by this.
This reverts commit 81fc3add1e627c23b7270fe2739cdacc09063e54.
This breaks some LLDB tests, e.g.
SymbolFile/DWARF/x86/no_unique_address-with-bitfields.cpp:
lldb: ../llvm-project/clang/lib/AST/Decl.cpp:4604: unsigned int clang::FieldDecl::getBitWidthValue() const: Assertion `isa<ConstantExpr>(getBitWidth())' failed.
Save the bitwidth value as a `ConstantExpr` with the value set. Remove
the `ASTContext` parameter from `getBitWidthValue()`, so the latter
simply returns the value from the `ConstantExpr` instead of
constant-evaluating the bitwidth expression every time it is called.
To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.
This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.
In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.
This reapplies d9a685a9dd589486e882b722e513ee7b8c84870c, which was
reverted because it broke ubsan bots. There seems to be a bug in
coroutine code-gen, which is causing EmitTypeCheck to use the wrong
alignment. For now, pass alignment zero to EmitTypeCheck so that it can
compute the correct alignment based on the passed type (see function
EmitCXXMemberOrOperatorMemberCallExpr).
To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.
This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.
In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.
This reapplies 8bd1f9116aab879183f34707e6d21c7051d083b6. The commit
broke msan bots because LValue::IsKnownNonNull was uninitialized.
To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.
This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.
In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.
- Update CodeGenTypeCache to use a single union for all pointers in
address space zero.
- Introduce a UnqualPtrTy in CodeGenTypeCache, and use that (for
example instead of llvm::PointerType::getUnqual) in some places.
- Drop some redundant bit/pointers casts from ptr to ptr.
`CGBuilderTy::CreateElementBitCast()` no longer does what its name suggests.
Remove remaining in-tree uses by one of the following methods.
* drop the call entirely
* fold it to an `Address` construction
* replace it with `Address::withElementType()`
This is a NFC cleanup effort.
Reviewed By: barannikov88, nikic, jrtc27
Differential Revision: https://reviews.llvm.org/D154285
Partial progress towards replacing in-tree uses of `Type::getPointerTo()`.
This needs to be done before deprecating the API.
Reviewed By: nikic, barannikov88
Differential Revision: https://reviews.llvm.org/D152321
Pushing the `CatchRetScope` early causes cleanups for catch parameters to be emitted in the basic block of the catch handler instead of the `catchret.dest` block. This is important because the latter is not part of the catchpad and this caused code truncations due to ARC PreISel intrinsics in WinEHPrepare.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D137939
On targets with non-default program address space (e.g., Harvard
architectures), clang crashes when emitting Objective-C method metadata,
because the address of the method IMP cannot be bitcast to i8*. It similarly
crashes at messenger callsite with a failed bitcast.
Define the _imp field instead as i8 addrspace(1)* (or whatever the target's
program address space is). And in getMessageSendInfo(), create signatureType by
specifying the program address space.
Add a regression test using the AVR target. Test failed previously and passes
now. Checked codegen of the test for x86_64-apple-darwin19.6.0 and saw no
difference, as expected.
Reviewed By: rjmccall, dylanmckay
Differential Revision: https://reviews.llvm.org/D112113
To make uses of the deprecated constructor easier to spot, and to
ensure that no new uses are introduced, rename it to
Address::deprecated().
While doing the rename, I've filled in element types in cases
where it was relatively obvious, but we're still left with 135
calls to the deprecated constructor.
non-Darwin ObjC runtimes:
- Use the same logic the Darwin runtime does for inferring that a
receiver is non-null and therefore doesn't require null checks.
Previously we weren't skipping these for non-super dispatch.
- Emit a null check when there's a consumed parameter so that we can
destroy the argument if the call doesn't happen. This mostly
involves extracting some common logic from the Darwin-runtime code.
- Generate a zero aggregate by zeroing the same memory that was used
in the method call instead of zeroing separate memory and then
merging them with a phi. This uses less memory and avoids unnecessary
copies.
- Emit zero initialization, and generate zero values in phis, using
the proper zero-value routines instead of assuming that the zero
value of the result type has a bitwise-zero representation.
This removes some (but not all) uses of type-less CreateGEP()
and CreateInBoundsGEP() APIs, which are incompatible with opaque
pointers.
There are a still a number of tricky uses left, as well as many
more variation APIs for CreateGEP.
- Fix a memory leak accidentally introduced yesterday by using CodeGen's
existing mangling context instead of creating a new context afresh.
- Move GNU-runtime ObjC method mangling into the AST mangler; this will
eventually be necessary to support direct methods there, but is also
just the right architecture.
- Make the Apple-runtime method mangling work properly when given an
interface declaration, fixing a bug (which had solidified into a test)
where mangling a category method from the interface could cause it to
be mangled as if the category name was a class name. (Category names
are namespaced within their class and have no global meaning.)
- Fix a code cross-reference in dsymutil.
Based on a patch by Ellis Hoag.
Summary:
Swift would like to use clang's apis to emit protocol declarations.
This commits adds the public API:
```
emitObjCProtocolObject(CodeGenModule &CGM, const ObjCProtocolDecl *p);
```
rdar://60888524
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77077
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
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
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
of only 'break'.
We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
the outer case.
I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.
Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu
Differential Revision: https://reviews.llvm.org/D53950
llvm-svn: 345882
Summary:
Introduces funclet-based unwinding for Objective-C and fixes an issue
where global blocks can't have their isa pointers initialised on
Windows.
After discussion with Dustin, this changes the name mangling of
Objective-C types to prevent a C++ catch statement of type struct X*
from catching an Objective-C object of type X*.
Reviewers: rjmccall, DHowett-MSFT
Reviewed By: rjmccall, DHowett-MSFT
Subscribers: mgrang, mstorsjo, smeenai, cfe-commits
Differential Revision: https://reviews.llvm.org/D50144
llvm-svn: 339428
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
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
According to the documentation, when encoding a bit-field, GNU runtime
needs its starting position in addition to its type and size.
https://gcc.gnu.org/onlinedocs/gcc/Type-encoding.html
Prior to r297702, the starting position information was not being
encoded, which is incorrect, and after r297702, an assertion started to
fail because an ObjCIvarDecl was being passed to a function expecting a
FieldDecl.
This commit moves LookupFieldBitOffset to ASTContext and uses the
function to encode the starting position of bit-fields.
llvm-svn: 306364
The assertion fails because EmitValueForIvarAtOffset doesn't get the
correct type of the ivar when the class the ivar belongs to is
parameterized. This commit fixes the function to compute the ivar's type
based on the type argument provided to the parameterized class.
rdar://problem/32461723
Differential Revision: https://reviews.llvm.org/D33698
llvm-svn: 304449
The functions creating LValues propagated information about alignment
source. Extend the propagated data to also include information about
possible unrestricted aliasing. A new class LValueBaseInfo will
contain both AlignmentSource and MayAlias info.
This patch should not introduce any functional changes.
Differential Revision: https://reviews.llvm.org/D33284
llvm-svn: 303358
Incorrect specification of the calling convention results in UB which can cause
the code path to be eliminated. Simplify the existing code by using the
RuntimeCall constructor in `CodeGenFunction`.
llvm-svn: 284154
Introduce an Address type to bundle a pointer value with an
alignment. Introduce APIs on CGBuilderTy to work with Address
values. Change core APIs on CGF/CGM to traffic in Address where
appropriate. Require alignments to be non-zero. Update a ton
of code to compute and propagate alignment information.
As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment
helper function to CGF and made use of it in a number of places in
the expression emitter.
The end result is that we should now be significantly more correct
when performing operations on objects that are locally known to
be under-aligned. Since alignment is not reliably tracked in the
type system, there are inherent limits to this, but at least we
are no longer confused by standard operations like derived-to-base
conversions and array-to-pointer decay. I've also fixed a large
number of bugs where we were applying the complete-object alignment
to a pointer instead of the non-virtual alignment, although most of
these were hidden by the very conservative approach we took with
member alignment.
Also, because IRGen now reliably asserts on zero alignments, we
should no longer be subject to an absurd but frustrating recurring
bug where an incomplete type would report a zero alignment and then
we'd naively do a alignmentAtOffset on it and emit code using an
alignment equal to the largest power-of-two factor of the offset.
We should also now be emitting much more aggressive alignment
attributes in the presence of over-alignment. In particular,
field access now uses alignmentAtOffset instead of min.
Several times in this patch, I had to change the existing
code-generation pattern in order to more effectively use
the Address APIs. For the most part, this seems to be a strict
improvement, like doing pointer arithmetic with GEPs instead of
ptrtoint. That said, I've tried very hard to not change semantics,
but it is likely that I've failed in a few places, for which I
apologize.
ABIArgInfo now always carries the assumed alignment of indirect and
indirect byval arguments. In order to cut down on what was already
a dauntingly large patch, I changed the code to never set align
attributes in the IR on non-byval indirect arguments. That is,
we still generate code which assumes that indirect arguments have
the given alignment, but we don't express this information to the
backend except where it's semantically required (i.e. on byvals).
This is likely a minor regression for those targets that did provide
this information, but it'll be trivial to add it back in a later
patch.
I partially punted on applying this work to CGBuiltin. Please
do not add more uses of the CreateDefaultAligned{Load,Store}
APIs; they will be going away eventually.
llvm-svn: 246985
tools/clang/test/CodeGen/packed-nest-unpacked.c contains this test:
struct XBitfield {
unsigned b1 : 10;
unsigned b2 : 12;
unsigned b3 : 10;
};
struct YBitfield {
char x;
struct XBitfield y;
} __attribute((packed));
struct YBitfield gbitfield;
unsigned test7() {
// CHECK: @test7
// CHECK: load i32, i32* getelementptr inbounds (%struct.YBitfield, %struct.YBitfield* @gbitfield, i32 0, i32 1, i32 0), align 4
return gbitfield.y.b2;
}
The "align 4" is actually wrong. Accessing all of "gbitfield.y" as a single
i32 is of course possible, but that still doesn't make it 4-byte aligned as
it remains packed at offset 1 in the surrounding gbitfield object.
This alignment was changed by commit r169489, which also introduced changes
to bitfield access code in CGExpr.cpp. Code before that change used to take
into account *both* the alignment of the field to be accessed within the
current struct, *and* the alignment of that outer struct itself; this logic
was removed by the above commit.
Neglecting to consider both values can cause incorrect code to be generated
(I've seen an unaligned access crash on SystemZ due to this bug).
In order to always use the best known alignment value, this patch removes
the CGBitFieldInfo::StorageAlignment member and replaces it with a
StorageOffset member specifying the offset from the start of the surrounding
struct to the bitfield's underlying storage. This offset can then be combined
with the best-known alignment for a bitfield access lvalue to determine the
alignment to use when accessing the bitfield's storage.
Differential Revision: http://reviews.llvm.org/D11034
llvm-svn: 241916
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
