When the load node which the broadcast instruction broadcasts has multiple uses, it cannot be folded.
A fallback pattern is added to catch these cases and provide another solution.
Differential Revision: https://reviews.llvm.org/D27661
llvm-svn: 289404
Summary:
Fix a corner case in `MDNode::getMostGenericTBAA` where we can sometimes
generate invalid TBAA metadata.
Reviewers: chandlerc, hfinkel, mehdi_amini, manmanren
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D26635
llvm-svn: 289403
Summary:
This change adds some verification in the IR verifier around struct path
TBAA metadata.
Other than some basic sanity checks (e.g. we get constant integers where
we expect constant integers), this checks:
- That by the time an struct access tuple `(base-type, offset)` is
"reduced" to a scalar base type, the offset is `0`. For instance, in
C++ you can't start from, say `("struct-a", 16)`, and end up with
`("int", 4)` -- by the time the base type is `"int"`, the offset
better be zero. In particular, a variant of this invariant is needed
for `llvm::getMostGenericTBAA` to be correct.
- That there are no cycles in a struct path.
- That struct type nodes have their offsets listed in an ascending
order.
- That when generating the struct access path, you eventually reach the
access type listed in the tbaa tag node.
Reviewers: dexonsmith, chandlerc, reames, mehdi_amini, manmanren
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D26438
llvm-svn: 289402
We have found that -- when the selected subarchitecture has a scheduling model
and we are not optimizing for size -- the machine-instruction combiner uses a
too-simple algorithm to compute the cost of one of the two alternatives [before
and after running a combining pass on a section of code], and therefor it throws
away the combination results too often.
This fix has the potential to help any ISA with the potential to combine
instructions and for which at least one subarchitecture has a scheduling model.
As of now, this is only known to definitely affect AArch64 subarchitectures with
a scheduling model.
Regression tested on AMD64/GNU-Linux, new test case tested to fail on an
unpatched compiler and pass on a patched compiler.
Patch by Abe Skolnik and Sebastian Pop.
llvm-svn: 289399
This is NFC today, but won't be once D27216 (or an equivalent patch) is
in.
This change fixes a design problem in SCEVExpander -- it relied on a
hoisting optimization to generate correct code for add recurrences.
This meant changing the hoisting optimization to not kick in under
certain circumstances (to avoid speculating faulting instructions, say)
would break correctness.
The fix is to make the correctness requirements explicit, and have it
not rely on the hoisting optimization for correctness.
llvm-svn: 289397
Regcall calling convention passes mask types arguments in x86 GPR registers.
The review includes the changes required in order to support v32i1, v16i1 and v8i1.
Differential Revision: https://reviews.llvm.org/D27148
llvm-svn: 289383
check file to not be unreasonably slow in the face of multiple check
prefixes.
The previous logic would repeatedly scan potentially large portions of
the check file looking for alternative prefixes. In the worst case this
would scan most of the file looking for a rare prefix between every
single occurance of a common prefix. Even if we bounded the scan, this
would do bad things if the order of the prefixes was "unlucky" and the
distant prefix was scanned for first.
None of this is necessary. It is straightforward to build a state
machine that recognizes the first, longest of the set of alternative
prefixes. That is in fact exactly whan a regular expression does.
This patch builds a regular expression once for the set of prefixes and
then uses it to search incrementally for the next prefix. This requires
some threading of state but actually makes the code dramatically
simpler. I've also added a big comment describing the algorithm as it
was not at all obvious to me when I started.
With this patch, several previously pathological test cases in
test/CodeGen/X86 are 5x and more faster. Overall, running all tests
under test/CodeGen/X86 uses 10% less CPU after this, and because all the
slowest tests were hitting this, finishes in 40% less wall time on my
system (going from just over 5.38s to just over 3.23s) on a release
build! This patch substantially improves the time of all 7 X86 tests
that were in the top 20 reported by --time-tests, 5 of them are
completely off the list and the remaining 2 are much lower. (Sadly, the
new tests on the list include 2 new X86 ones that are slow for unrelated
reasons, so the count stays at 4 of the top 20.)
It isn't clear how much this helps debug builds in aggregate in part
because of the noise, but it again makes mane of the slowest x86 tests
significantly faster (10% or more improvement).
llvm-svn: 289382
This fixes one formatting goof I left in my previous commit and *many*
other inconsistencies.
I'm planning to make substantial changes here and so wanted to get to
a clean baseline.
llvm-svn: 289379
make some readability improvements.
Both the check file and input file have to be fully buffered to
normalize their whitespace. But previously this would be done in a stack
SmallString and then copied into a heap allocated MemoryBuffer. That
seems pretty wasteful, especially for something like FileCheck where
there are only ever two such entities.
This just rearranges the code so that we can keep the canonicalized
buffers on the stack of the main function, use reasonably large stack
buffers to reduce allocation. A rough estimate seems to show that about
80% of LLVM's .ll and .s files will fit into a 4k buffer, so this should
completely avoid heap allocation for the buffer in those cases. My
system's malloc is fast enough that the allocations don't directly show
up in timings. However, on some very slow test cases, this saves 1% - 2%
by avoiding the copy into the heap allocated buffer.
This also splits out the code which checks the input into a helper much
like the code to build the checks as that made the code much more
readable to me. Nit picks and suggestions welcome here. It has really
exposed a *bunch* of stuff that could be cleaned up though, so I'm
probably going to go and spring clean all of this code as I have more
changes coming to speed things up.
llvm-svn: 289378
This teaches SimplifyDemandedElts that the FMA can be removed if the lower element isn't used. It also teaches it that if upper elements of the first operand aren't used then we can simplify them.
llvm-svn: 289377
In certain OS versions, it was possible that libmalloc replaced the sanitizer zone from being the default zone (i.e. being in malloc_zones[0]). This patch introduces a failsafe that makes sure we always stay the default zone. No testcase for this, because this doesn't reproduce under normal circumstances.
Differential Revision: https://reviews.llvm.org/D27083
llvm-svn: 289376
We currently have a interceptor for malloc_create_zone, which returns a new zone that redirects all the zone requests to our sanitizer zone. However, calling malloc_destroy_zone on that zone will cause libmalloc to print out some warning messages, because the zone is not registered in the list of zones. This patch handles this and adds a testcase for that.
Differential Revision: https://reviews.llvm.org/D27083
llvm-svn: 289375
iteration.
Instead, load the byte at the needle length, compare it directly, and
save it to use in the lookup table of lengths we can skip forward.
I also added an annotation to expect that the comparison fails so that
the loop gets laid out contiguously without the call to memcpy (and the
substantial register shuffling that the ABI requires of that call).
Finally, because this behaves especially badly with a needle length of
one (by calling memcmp with a zero length) special case that to directly
call memchr, which is what we should have been doing anyways.
This was motivated by the fact that there are a large number of test
cases in 'check-llvm' where FileCheck's performance is dominated by
calls to StringRef::find (in a release, no-asserts build). I'm working
on patches to generally improve matters there, but this alone was worth
a 12.5% improvement in one test case where FileCheck spent 92% of its
time in this routine.
I experimented a bunch with different minor variations on this theme,
for example setting the pointer *at* the last byte and indexing
backwards for the call to memcmp. That didn't improve anything on this
version and seemed more complex. I also tried other things to make the
loop flow more nicely and none worked. =/ It is a bit unfortunate, the
generated code here remains pretty gross, but I don't see any obvious
ways to improve it. At this point, most of my ideas would be really
elaborate:
1) While the remainder of the string is long enough, we could load
a 16-byte or 32-byte vector at the address of the last byte and use
palignr to rotate that and check the first 15- or 31-bytes at the
front of the next segment, essentially pre-loading the first several
bytes of the next iteration so we could quickly detect a mismatch in
those bytes without an additional memory access. Down side would be
the code complexity, having a fallback loop, and likely misaligned
vector load. Plus it would make the common case of the last byte not
matching somewhat slower (need some extraction from a vector).
2) While we have space, we could do an aligned load of a 16- or 32-byte
vector that *contains* the end byte, and use any peceding bytes to
have a more precise "no" test, and any subsequent bytes could be
saved for the next iteration. This remove any unaligned load penalty,
but still requires us to pay the overhead of vector extraction for
the cases where we didn't need to do anything other than load and
compare the last byte.
3) Try to walk from the last byte in a way that is more friendly to
cache and/or memory pre-fetcher considering we have to poke the last
byte anyways.
No idea if any of these are really worth pursuing though. They all seem
somewhat unlikely to yield big wins in practice and to be a lot of work
and complexity. So I settled here, which at least seems like a strict
improvement over the previous version.
llvm-svn: 289373
These intrinsics don't read the upper elements of their first and second input. These are slightly different the the SSE version which does use the upper bits of its first element as passthru bits since the result goes to an XMM register. For AVX-512 the result goes to a mask register instead.
llvm-svn: 289371
These intrinsics don't read the upper bits of their second input. And the third input is the passthru for masking and that only uses the lower element as well.
llvm-svn: 289370
Include headermaps (.hmap files) in the .cache directory and
add VFS entries. All headermaps are known after HeaderSearch
setup, collect them right after.
rdar://problem/27913709
llvm-svn: 289360
These swap tests were swapping non-POCS non-equal allocators which
is undefined behavior. This patch changes the tests to use allocators
which compare equal. In order to test that the allocators were not
swapped I added an "id" field to test_allocator which does not
participate in equality but does propagate across copies/swaps.
This patch is based off of D26623 which was submitted by STL.
llvm-svn: 289358
This will allow the backend to constant fold these to generic shuffle vectors like 128-bit and 256-bit without having to working about handling masking.
llvm-svn: 289351
Summary:
The underlying C locales provide the `thousands_sep` and `decimal_point` as strings, possible with more than one character. We currently don't handle this case even for `wchar_t`.
This patch properly converts the mbs -> wide character for `moneypunct_byname<wchar_t>`. For the `moneypunct_byname<char>` case we attempt to narrow the WC and if that fails we also attempt to translate it to some reasonable value. For example we translate U00A0 (non-breaking space) into U0020 (regular space). If none of these conversions succeed then we simply allow the base class to provide a fallback value.
Reviewers: mclow.lists, EricWF
Subscribers: vangyzen, george.burgess.iv, cfe-commits
Differential Revision: https://reviews.llvm.org/D24218
llvm-svn: 289347
This will allow the backend to constant fold these to generic shuffle vectors like 128-bit and 256-bit without having to working about handling masking.
llvm-svn: 289345
Simon Pilgrim