This change allows us to infer access attributes (readnone, readonly) on arguments passed to vararg functions. Since there isn't a formal argument corresponding to the parameter, they'll never be considered part of the speculative SCC, but they can still benefit from attributes on the call site or the callee function.
The main motivation here is just to simplify the code, and remove some special casing. Previously, an indirect vararg call could return more precise results than an direct vararg call which is just weird.
Differential Revision: https://reviews.llvm.org/D115964
This fixes a bug where we would infer readnone/readonly for a function which passed a value to a function which could capture it. With the value captured in memory, the function could reload the value from memory after the call, and write to it. Inferring the argument as readnone or readonly is unsound.
@jdoerfert apparently noticed this about two years ago, and tests were checked in with 76467c4, but the issue appears to have never gotten fixed.
Since this seems like this issue should break everything, let me explain why the case is actually fairly narrow. The main inference loop over the argument SCCs only analyzes nocapture arguments. As such, we can only hit this when construction the partial SCCs. Due to that restriction, we can only hit this when we have either a) a function declaration with a manually annotated argument, or b) an immediately self recursive call.
It's also worth highlighting that we do have cases we can infer readonly/readnone on a capturing argument validly. The easiest example is a function which simply returns its argument without ever accessing it.
Differential Revision: https://reviews.llvm.org/D115961
1) remove verbose information (function linkage types, alignment, TBAA) 2) remove unused element or replace irrelevant element with null (as placeholders) in virtual table, remove unused definitions of deleted elements accordingly.
Differential Revision: https://reviews.llvm.org/D116071
Converts concat_vectors((trunc (lshr)), (trunc (lshr))) to UZP2
when the shift amount is half the width of the vector element.
Differential Revision: https://reviews.llvm.org/D116021
Creating threads after a multi-threaded fork is semi-supported,
we don't give particular guarantees, but we try to not fail
on simple cases and we have die_after_fork=0 flag that enables
not dying on creation of threads after a multi-threaded fork.
This flag is used in the wild:
23c052e3e3/SConstruct (L3599)
fork_multithreaded.cpp test started hanging in debug mode
after the recent "tsan: fix deadlock during race reporting" commit,
which added proactive ThreadRegistryLock check in SlotLock.
But the test broke earlier after "tsan: remove quadratic behavior in pthread_join"
commit which made tracking of alive threads based on pthread_t stricter
(CHECK-fail on 2 threads with the same pthread_t, or joining a non-existent thread).
When we start a thread after a multi-threaded fork, the new pthread_t
can actually match one of existing values (for threads that don't exist anymore).
Thread creation started CHECK-failing on this, but the test simply
ignored this CHECK failure in the child thread and "passed".
But after "tsan: fix deadlock during race reporting" the test started hanging dead,
because CHECK failures recursively lock thread registry.
Fix this purging all alive threads from thread registry on fork.
Also the thread registry mutex somehow lost the internal deadlock detector id
and was excluded from deadlock detection. If it would have the id, the CHECK
wouldn't hang because of the nested CHECK failure due to the deadlock.
But then again the test would have silently ignore this error as well
and the bugs wouldn't have been noticed.
Add the deadlock detector id to the thread registry mutex.
Also extend the test to check more cases and detect more bugs.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116091
To allow transition from the TS-specified
std::experimental::coroutine_traits to the C++20-specified
std::coroutine_traits, we lookup in both places and provide helpful
diagnostics. This refactors the code to avoid separate paths to
std::experimental lookups.
Reviewed By: ChuanqiXu
Differential Revision: https://reviews.llvm.org/D116029
Add test for various customization point object properties as defined by
the Standard. Test various CPOs from `<ranges>`, `<iterator>`,
`<concepts>`, etc.
The test is mostly from https://reviews.llvm.org/D107036 and split up
into this.
Differential Revision: https://reviews.llvm.org/D115588
This fixes a typo/bug when checking for pointer reuse when testing
DI location preservation in the Debugify original mode (when
checking -g generated Debug Info).
Differential Revision: https://reviews.llvm.org/D115621
Add an overload that accepts and returns an Address, as we
generally just want to replace the pointer with a laundered one,
while retaining remaining information.
* There is no reason to forbid that case
* Also, user will get very unfriendly error like `expected result type with offset = -9223372036854775808 instead of 1`
Differential Revision: https://reviews.llvm.org/D114678
Move shift-by-constant handling and move it into its only user (VSHIFT intrinsics lowering).
This is some prep-work for getTargetVShiftNode to no longer take a scalar shift amount - we're introducing temporary ISD::EXTRACT_VECTOR_ELT nodes via SelectionDAG::getSplatValue to accommodate this which can cause various issues, including unnecessary scalarization and xmm->gpr->xmm transfers, and causes problems for 32-bit codegen if we fail to remove an (illegal) i64 scalar extracted from a (legal) vXi64 vector.
Allow `__move_constexpr` to work with unrelated pointers and `_LIBCPP_ASSERT` that `__copy_constexpr`, `__move_constexpr` and `__assign_constexpr` are only run during constant evaluation
Reviewed By: ldionne, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D115986
If we miss both close of a file descriptor and a subsequent open
if the same file descriptor number, we report false positives
between operations on the old and on the new descriptors.
There are lots of ways to create new file descriptors, but for closing
there is mostly close call. So we try to handle at least it.
However, if the close happens in an ignored library, we miss it
and start reporting false positives.
Handle closing of file descriptors always, even in ignored libraries
(as we do for malloc/free and other critical functions).
But don't imitate memory accesses on close for ignored libraries.
FdClose checks validity of the fd (fd >= 0) itself,
so remove the excessive checks in the callers.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116095
Pull out the "rotl(x,y) --> (unpack(x,x) << zext(splat(y % bw))) >> bw" special case from vXi8 lowering so we can reuse it for vXi32 types as well.
There's still some regressions with vXi16 to handle before this becomes entirely general.
It also allows us to remove the now unnecessary hack for handling amount-modulo before splatting.
Rename option MaxConstantsThreshold to MaxClonesThreshold. Not only is this
more descriptive, this is also in preparation of introducing another threshold
to analyse more than just 1 constant argument as we currently do, and to better
distinguish these options/thresholds.
Script (llvm-mca-compare.py) uses llvm-mca tool to print
statistics in console for multiple files.
Script requires specified --llvm-mca-binary option (specified
relative path to binary of llvm-mca).
Options: --args [="-option1=<arg> -option2=<arg> ..."], -v or -h can also be used.
The script is used as follows:
$ llvm-project/llvm/utils/llvm-mca-compare.py file1.s --llvm-mca-binary=build/bin/llvm-mca
Patch by Milica Matic <Milica.Matic@syrmia.com>
Differential Revision: https://reviews.llvm.org/D115138
Attempt to lower a shuffle as a permute instruction(zip/uzp/trn) for fixed length SVE.
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D113376
We used to use u64 as mutex id because it was some
tricky identifier built from address and reuse count.
Now it's just the mutex index in the report (0, 1, 2...),
so use int to represent it.
Depends on D112603.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D113980
These callbacks are used for SSE vector accesses.
In some computational programs these accesses dominate.
Currently we do 2 uninlined 8-byte accesses to handle them.
Inline and optimize them similarly to unaligned accesses.
This reduces the vector access benchmark time from 8 to 3 seconds.
Depends on D112603.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D114594
This commit adds two test about template class instantiation in
transitively imported module. They are used as pre-commit tests for
successive patches.
Depends on D115940 for the `Binary_rv_vr_vv` pattern class op isel
fragment used for divisions.
Reviewed By: kaz7
Differential Revision: https://reviews.llvm.org/D116035
This fixes the assertion failure reported at
https://reviews.llvm.org/D114889#3198921 with a straightforward
check, until the cleaner fix in D115924 can be reapplied.
Philip Reames