I discovered a case where the old algorithm would crash. Instead of
trying to patch the algorithm, rewrite it. The new algorithm operates
in three phases:
1. Find all paths to the subobject with the vptr.
2. Remove paths which are subsets of other paths.
3. Select the best path where 'best' is defined as introducing the most
covariant overriders. If two paths introduce different overriders,
raise a diagnostic.
llvm-svn: 236444
This test verifies that we can detect when the inheritance paths are
ambiguous due to covariant thunks, ensuring we don't regress PR16759.
llvm-svn: 236381
A class might contain multiple ways of getting to a vbase, some of which
are virtual and other non-virtual. It may be the case that a
non-virtual base contains an override of a method in a vbase. This
means that we must carefully pick between a set of nvbases to determine
which is the best.
As a consequence, the findPathForVPtr algorithm is considerably simpler.
llvm-svn: 236353
There can be multiple virtual bases which are on the path to a vfptr
when one vbase virtually inherits from another. We should prefer the
most derived virtual base which covariantly overrides a method in the
vfptr class; if we do not lengthen the path this way, we will end up
with too few vftable entries.
This fixes PR21073.
llvm-svn: 236239
Summary:
Hexagon is being updated, but there is not enough to pass these tests.
These sections are now on top of Colin's list.
Test Plan: Ran changes on hexagon-build-03.
Reviewers: colinl, rfoos
Reviewed By: rfoos
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D9356
llvm-svn: 236173
and as artificial local variables in the debug info.
This is a follow-up to r236059. We can't get rid of the local variables
entirely because the gdb buildbot depends on them, but we can mark them
as artificial while still emitting the correct debug info. As I learned
from review comments other compilers also follow this model.
A paired commit in LLVM temporarily relaxes the debug info verifier to
not check the integrity of DW_OP_bit_pieces of artificial variables.
rdar://problem/20730771
llvm-svn: 236125
LLVM r236120 renamed debug info IR constructs to use a `DI` prefix, now
that the `DIDescriptor` hierarchy has been gone for about a week. This
commit was generated using the rename-md-di-nodes.sh upgrade script
attached to PR23080, followed by running clang-format-diff.py on the
`lib/` portion of the patch.
llvm-svn: 236121
in the debug info. This patch deletes a hack that emits the members
of local anonymous unions as local variables.
Besides being morally wrong, the existing representation using local
variables breaks internal assumptions about the local variables' storage
size.
Compiling
```
void fn1() {
union {
int i;
char c;
};
i = c;
}
```
with -g -O3 -verify will cause the verifier to fail after SROA splits
the 32-bit storage for the "local variable" c into two pieces because the
second piece is clearly outside the 8-bit range that is expected for a
variable of type char. Given the choice I'd rather fix the debug
representation than weaken the verifier.
Debuggers generally already know how to deal with anonymous unions when
they are members of C++ record types, but they may have problems finding
the local anonymous struct members in the expression evaluator.
rdar://problem/20730771
llvm-svn: 236059
This was a bug in r218285 that prevented us from seeing subsequent
virtual bases in the class hierarchy, leading to crashes later.
Also add some comments to this function, now that we better understand
what it's trying to do.
Fixes PR21062 and PR21064.
llvm-svn: 235899
Fixes rdar://20621065.
A more elegant fix would preclude this case by defining the
rules such that zero-size classes are always formally empty.
I believe the only extensions which create zero-size classes
right now are flexible arrays and zero-length arrays; it's
not abstractly unreasonable to say that those don't count
as members for the purposes of emptiness, just as zero-width
bitfields don't count. But that's an ABI-affecting change
and requires further discussion; in the meantime, let's not
assert / miscompile.
llvm-svn: 235815
Type backreferences for arguments use the DecayedType's original type.
Because of this, arguments with the same canonical type with the same
mangling would not backreference each other if one was a
ConstantArrayType while the other was an IncompleteArrayType. Solve
this by canonicalizing the ConstantArrayType to a suitable
IncompleteArrayType.
This fixes PR23325.
llvm-svn: 235572
These extra endcatch markers aren't helping identify regions to outline,
so let's get rid of them. LLVM outlines (more or less) from begincatch
to endcatch. Any unwind edge from an enclosed invoke is a transition to
a new exception handler, which has it's own outlining markers.
llvm-svn: 235562
This reverts commit r234700. It turns out that the lifetime markers
were not the cause of Chromium failing but a bug which was uncovered by
optimizations exposed by the markers.
llvm-svn: 235553
Otherwise -fno-omit-frame-pointer and other flags like it aren't
applied.
Basic idea taken from Gao's patch, thanks!
Differential Revision: http://reviews.llvm.org/D9203
llvm-svn: 235537
For example, a function taking a parameter with internal linkage will
itself have internal linkage since it cannot be called outside the
translation unit.
Differential Revision: http://reviews.llvm.org/D9182
llvm-svn: 235471
This reverts commit r234767, as it was breaking all ARM buildbots for two days and the
assert is not in the code, making it difficult to spot the error, which would keep the
bots red for a few more days. New errors were silently introduced because of this bug,
and we don't want this to escalate.
llvm-svn: 234983
Reverts the code changes from r234675 but keeps the test case.
We were already maintaining a DenseMap of globals with dynamic
initializers anyway.
Fixes the test case from PR23234.
llvm-svn: 234961
Now that TailRecursionElimination has been fixed with r222354, the
threshold on size for lifetime marker insertion can be removed. This
only affects named temporary though, as the patch for unnamed temporaries
is still in progress.
My previous commit (r222993) was not handling debuginfo correctly, but
this could only be seen with some asan tests. Basically, lifetime markers
are just instrumentation for the compiler's usage and should not affect
debug information; however, the cleanup infrastructure was assuming it
contained only destructors, i.e. actual code to be executed, and was
setting the breakpoint for the end of the function to the closing '}', and
not the return statement, in order to show some destructors have been
called when leaving the function. This is wrong when the cleanups are only
lifetime markers, and this is now fixed.
llvm-svn: 234581
_CxxFrameHandler3 calls terminate if a cleanup action throws, regardless
of what bits you put in the xdata tables. There's no need to model this
in the IR, since we just have to take it out later.
llvm-svn: 234448
The test should be fixed. It was failing in NDEBUG builds due to a
missing '*' character in a regex. In asserts builds, the pattern matched
a single digit value, which became a double digit value in NDEBUG
builds. Go figure.
This reverts commit r234261.
llvm-svn: 234447
It breaks down on this test case:
void foo();
template <typename T> class C {
friend void foo();
};
inline void foo() {}
C<int> c;
We shouldn't be marking the instantiation of the friend decl of foo as
inline-specified. It may be possible to fix this by determining if the
full definition is part of the current template, but it seems better to
rever tot green until we come up with a full solution.
This reverts commit r233817, as well as follow-ups r233820 and r233821.
llvm-svn: 234355
The catch object parameter to llvm.eh.begincatch is optional, and can be
null. We can save some ourselves the stack space, copy ctor, and dtor
calls if we pass null.
llvm-svn: 234264
While capturing filters aren't very common, we'd like to outline
__finally blocks in the frontend to simplify -O0 EH preparation and
reduce code size. Finally blocks are usually have captures, and this is
the first step towards that.
Currently we don't support capturing 'this' or VLAs.
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D8825
llvm-svn: 234261
Don't assume that all pointers are convertible to void pointer.
Instead correctly respect [conv.ptr]p2; only allow pointer types with an
object pointee type to be caught as pointer-to-void.
llvm-svn: 234090
