Commit 009f3a89d8 ("BPF: remove intrindics @llvm.stacksave()
and @llvm.stackrestore()") implemented IRPeephole pass to remove
llvm.stacksave()/stackrestore() instrinsics.
Buildbot reported a failure:
UNREACHABLE executed at ../lib/IR/LegacyPassManager.cpp:1445!
which is:
llvm_unreachable("Pass modifies its input and doesn't report it");
The code has changed but the implementation didn't return true
for changing. This patch fixed this problem.
The following tests are failing because 64-bit XCOFF object files are not currently supported on AIX. This patch disables these tests on AIX for now.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D111887
This simplifies the return value of addRuntimeCheck from a pair of
instructions to a single `Value *`.
The existing users of addRuntimeChecks were ignoring the first element
of the pair, hence there is not reason to track FirstInst and return
it.
Additionally all users of addRuntimeChecks use the second returned
`Instruction *` just as `Value *`, so there is no need to return an
`Instruction *`. Therefore there is no need to create a redundant
dummy `and X, true` instruction any longer.
Effectively this change should not impact the generated code because the
redundant AND will be folded by later optimizations. But it is easy to
avoid creating it in the first place and it allows more accurately
estimating the cost of the runtime checks.
Starting with a mostly NFC change to be able to differentiate between
mechanical changes from ones that require more detailed review.
This will be used to flush out flow before flipping dialects used
outside local testing. As this dialect is not intended to be used
generally rather than in tests in core, I will not be following 2 week
staging approach here.
This function was copied from ARM where register pairs/triples/quads can wrap around the 32 encoding space. So register 31 can pair with register 0. This is not true for RISCV vectors. The spec specifically mentions the possibility of a future encoding that has more than 32 registers.
This patch removes the modulo from the code and directly checks that destination register is in the source register range and not the beginning of the range. Though I don't expect an identity copy will occur.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D111467
Paul Chaignon reported a bpf verifier failure ([1]) due to using
non-ABI register R11. For the test case, llvm11 is okay while
llvm12 and later generates verifier unfriendly code.
The failure is related to variable length array size.
The following mimics the variable length array definition
in the test case:
struct t { char a[20]; };
void foo(void *);
int test() {
const int a = 8;
char tmp[AA + sizeof(struct t) + a];
foo(tmp);
...
}
Paul helped bisect that the following llvm commit is
responsible:
552c6c2328 ("PR44406: Follow behavior of array bound constant
folding in more recent versions of GCC.")
Basically, before the above commit, clang frontend did constant
folding for array size "AA + sizeof(struct t) + a" to be 68,
so used alloca for stack allocation. After the above commit,
clang frontend didn't do constant folding for array size
any more, which results in a VLA and llvm.stacksave/llvm.stackrestore
is generated.
BPF architecture API does not support stack pointer (sp) register.
The LLVM internally used R11 to indicate sp register but it should
not be in the final code. Otherwise, kernel verifier will reject it.
The early patch ([2]) tried to fix the issue in clang frontend.
But the upstream discussion considered frontend fix is really a
hack and the backend should properly undo llvm.stacksave/llvm.stackrestore.
This patch implemented a bpf IR phase to remove these intrinsics
unconditionally. If eventually the alloca can be resolved with
constant size, r11 will not be generated. If alloca cannot be
resolved with constant size, SelectionDag will complain, the same
as without this patch.
[1] https://lore.kernel.org/bpf/20210809151202.GB1012999@Mem/
[2] https://reviews.llvm.org/D107882
Differential Revision: https://reviews.llvm.org/D111897
This patch allows to simplify compiler implementation on "taskwait nowait"
construct. The "taskwait nowait" is semantically equivalent to the empty task.
Instead of creating an empty routine as a task entry, compiler can just send
NULL pointer to the runtime. Then the runtime will make all the work with
dependences and return because of the absent task routine.
Differential Revision: https://reviews.llvm.org/D112015
Besides accessing the record, there is currently no way to access all possible
constraint informations, such as the base constraint of a variadic constraint
for example.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D111719
AnyAttrOf, similar to AnyTypeOf, expects the attribute to be one of the
given attributes.
For instance, `AnyAttrOf<[I32Attr, StrAttr]>` expects either a `I32Attr`,
or a `StrAttr`.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D111739
This change is derived from a test case we have locally but I could not
see an equivalent in LLD's testing.
Differential Revision: https://reviews.llvm.org/D111803
This removes edge cases where the default flags we want to use
during printing (e.g. local scope, eliding attributes, etc.)
get missed/dropped.
Differential Revision: https://reviews.llvm.org/D111761
Record widening decisions for memory operations within the planned recipes and
use the recorded decisions in code-gen rather than querying the cost model.
Differential Revision: https://reviews.llvm.org/D110479
When folding A->B->C => A->C only accept A->C that is valid shape cast
Reviewed By: ThomasRaoux, nicolasvasilache
Differential Revision: https://reviews.llvm.org/D111473
The MIPS ABI requires the thread pointer be accessed via rdhwr $3, $r29.
This is currently represented by (CopyToReg $3, (RDHWR $29)) followed by
a (CopyFromReg $3). However, there is no glue between these, meaning
scheduling can break those apart. In particular, PR51691 is a report
where PseudoSELECT_I was moved to between the CopyToReg and CopyFromReg,
and since its expansion uses branches, it split the def and use of the
physical register between two basic blocks, resulting in the def being
eliminated and the use having no def. It also seems possible that a
similar situation could arise splitting up the CopyToReg from the RDHWR,
causing the RDHWR to use a destination register other than $3, violating
the ABI requirement.
Thus, add glue between all three nodes to ensure they aren't split up
during instruction selection. No regression test is added since any test
would be implictly relying on specific scheduling behaviour, so whilst
it might be testing that glue is preventing reordering today, changes to
scheduling behaviour could result in the test no longer being able to
catch a regression here, as the reordering might no longer happen for
other unrelated reasons.
Fixes PR51691.
Reviewed By: atanasyan, dim
Differential Revision: https://reviews.llvm.org/D111967
Right now we only set a dependency on libc++ when the host is Darwin, which
means that libc++ in the build directory is in some undefined state when running
the test suite (it can be fully built, out-of-date or missing). Depending on
whether we have a system libc++ (which LLDB also supports running the libc++
tests against), the outcome is that we sometimes skip the libc++ tests or we run
the tests against a mix of ToT-libc++/system-libc++ (e.g., we compile against
the ToT-libc++ headers and link against the system libc++ library).
This can be demonstrated via `export LIT_FILTER=TestDataFormatterLibcxxSet ninja
check-lldb-api` (or any other libc++ test) and then gradually building parts of
libc++ in the same build (which will slowly change the test behaviour from
`UNSUPPORTED` to various failures to passing depending on how much of libcxx is
built at test time).
Note that this effectively re-enables the (unintentionally) disabled libc++
formatter tests on Linux. Don't revert this if it breaks a libc++ LLDB test,
instead please @skipIf decorate the failing test (as it was probably already
failing before this commit).
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D111981
Try to widen element type to get a new mask value for a better permutation
sequence, so that we can use NEON shuffle instructions, such as zip1/2,
UZP1/2, TRN1/2, REV, INS, etc.
For example:
shufflevector <4 x i32> %a, <4 x i32> %b, <4 x i32> <i32 6, i32 7, i32 2, i32 3>
is equivalent to:
shufflevector <2 x i64> %a, <2 x i64> %b, <2 x i32> <i32 3, i32 1>
Finally, we can get:
mov v0.d[0], v1.d[1]
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D111619
It's been broken (not failing, but not testing anything either) for
quite some time now, and nobody noticed. It also (by design) tests
stepping through libc code, which makes it completely non-hermetic.
It's not worth reviving such a test.
This is NFC-intended for the callers. Posting in case there are
other potential users that I missed.
I would also use this from VectorCombine in a patch for:
https://llvm.org/PR52178 ( D111901 )
Differential Revision: https://reviews.llvm.org/D111891
Fallback to stringification and string comparison if we cannot compare
the `IdentifierInfo`s, which is the case for C++ overloaded operators,
constructors, destructors, etc.
Examples:
{ "std", "basic_string", "basic_string", 2} // match the 2 param std::string constructor
{ "std", "basic_string", "~basic_string" } // match the std::string destructor
{ "aaa", "bbb", "operator int" } // matches the struct bbb conversion operator to int
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D111535
Refactor the code to make it more readable.
It will set up further changes, and improvements to this code in
subsequent patches.
This is a non-functional change.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D111534
This NFC change accomplishes three things:
1) Splits up the single unittest into reasonable segments.
2) Extends the test infra using a template to select the AST-node
from which it is supposed to construct a `CallEvent`.
3) Adds a *lot* of different tests, documenting the current
capabilities of the `CallDescription`. The corresponding tests are
marked with `FIXME`s, where the current behavior should be different.
Both `CXXMemberCallExpr` and `CXXOperatorCallExpr` are derived from
`CallExpr`, so they are matched by using the default template parameter.
On the other hand, `CXXConstructExpr` is not derived from `CallExpr`.
In case we want to match for them, we need to pass the type explicitly
to the `CallDescriptionAction`.
About destructors:
They have no AST-node, but they are generated in the CFG machinery in
the analyzer. Thus, to be able to match against them, we would need to
construct a CFG and walk on that instead of simply walking the AST.
I'm also relaxing the `EXPECT`ation in the
`CallDescriptionConsumer::performTest()`, to check the `LookupResult`
only if we matched for the `CallDescription`.
This is necessary to allow tests in which we expect *no* matches at all.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D111794
__ompt_get_task_info_internal is now able to determine the right value of the
“thread_num” argument during the execution of an explicit task.
During the execution of a while loop that iterates over the ancestor tasks
hierarchy, the “prev_team” variable was always set to “team” variable at the
beginning of each loop iteration.
Assume that the program contains a parallel region which encloses an explicit
task executed by the worker thread of the region. Also assume that the tool
inquires the “thread_num” of a worker thread for the implicit task that
corresponds to the region (task at “ancestor_level == 1”) and expects to
receive the value of “thread_num > 0”.
After the loop finishes, both “team” and “prev_team” variables are equal and
point to the team information of the parallel region.
The “thread_num” is set to “prev_team->t.t_master_tid”, that is equal to
“team->t.t_master_tid”. In this case, “team->t.t_master_tid” is 0, since
the master thread of the region is the initial master thread of the program.
This leads to a contradiction.
To prevent this, “prev_team” variable is set to “team” variable only at the
time when the loop that has already encountered the implicit task (“taskdata”
variable contains the information about an implicit task) continues iterating
over the implicit task’s ancestors, if any.
After the mentioned loop finishes, the “prev_team” variable might be equal to
NULL. This means that the task at requested “ancestor_level” belongs to the
innermost parallel region, so the “thread_num” will be determined by calling
the “__kmp_get_tid”.
To prove that this patch works, the test case “explicit_task_thread_num.c” is
provided.
It contains the example of the program explained earlier in the summary.
Differential Revision: https://reviews.llvm.org/D110473
Older intel compilers miss the privatization of nested loop variables for
doacross loops. Declaring the variable in the loop makes the test more
robust.
As reported on https://pvs-studio.com/en/blog/posts/cpp/0771/ (Snippet 2) - (and mentioned on rGdc4259d5a38409) we are repeating the T1.isNull() check instead of checking T2.isNull() as well, and at this point neither should be null - so we're better off with an assertion.
Differential Revision: https://reviews.llvm.org/D107347
Fixes an issue where GEP salvaging did not properly account for GEP
instructions which stepped over array elements of width 0 (effectively a
no-op). This unnecessarily produced long expressions by appending
`... + (x * 0)` and potentially extended the number of SSA values used
in the dbg.value. This also erroneously triggered an assert in the
salvage function that the element width would be strictly positive.
These issues are resolved by simply ignoring these useless operands.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D111809