Try to fold:
memcmp(X, C, ConstantLength) == 0 --> load X == *C
Without this change, we're unnecessarily checking the alignment of the constant data,
so we miss the transform in the first 2 tests in the patch.
I noted this shortcoming of LibCallSimpifier in one of the recent CGP memcmp expansion
patches. This doesn't help the example in:
https://bugs.llvm.org/show_bug.cgi?id=34032#c13
...directly, but it's worth short-circuiting more of these simple cases since we're
already trying to do that.
The benefit of transforming to load+cmp is that existing IR analysis/transforms may
further simplify that code. For example, if the load of the variable is common to
multiple memcmp calls, CSE can remove the duplicate instructions.
Differential Revision: https://reviews.llvm.org/D36922
llvm-svn: 311333
Preparations to use the per-increment are sometimes done in the target
independent pass Loop Strength Reduction. We try to detect them in the PowerPC
specific pass so that they are not done twice and so that we do not add PHIs
that are not required.
Differential Revision: https://reviews.llvm.org/D36736
llvm-svn: 311332
Re-committing after r311325 fixed an unintentional use of '#' comments in
clang.
The '#' token is not a comment for all targets (on ARM and AArch64 it marks an
immediate operand), so we shouldn't treat it as such.
Comments are already converted to AsmToken::EndOfStatement by
AsmLexer::LexLineComment, so this check was unnecessary.
Differential Revision: https://reviews.llvm.org/D36405
llvm-svn: 311326
widely used processors.
This occured to me when I saw that we were generating 'inc' and 'dec'
when for Haswell and newer we shouldn't. However, there were a few "X is
slow" things that we should probably just set.
I've avoided any of the "X is fast" features because most of those would
be pretty serious regressions on processors where X isn't actually fast.
The slow things are likely to be negligible costs on processors where
these aren't slow and a significant win when they are slow.
In retrospect this seems somewhat obvious. Not sure why we didn't do
this a long time ago.
Differential Revision: https://reviews.llvm.org/D36947
llvm-svn: 311318
rather than doing a separate comparison.
This both saves an explicit comparision and avoids the use of `xadd`
which introduces register constraints and other challenges to the
generated code.
The motivating case is from atomic reference counts where `1` is the
sentinel rather than `0` for whatever reason. This can and should be
lowered efficiently on x86 by just using a different flag, however the
x86 code only handled the `0` case.
There remains some further opportunities here that are currently hidden
due to canonicalization. I've included test cases that show these and
FIXMEs. However, I don't at the moment have any production use cases and
they seem substantially harder to address.
Differential Revision: https://reviews.llvm.org/D36945
llvm-svn: 311317
parallel_for_each_n splits a given task into small pieces of tasks and then
passes them to background threads managed by a thread pool to process them
in parallel. TaskGroup then waits for all tasks to be done, which is done by
TaskGroup's destructor.
In the previous code, all tasks were passed to background threads, and the
main thread just waited for them to finish their jobs. This patch changes
the logic so that the main thread processes a task just like other
worker threads instead of just waiting for workers.
This patch improves the performance of parallel_for_each_n for a task which
is too small that we do not split it into multiple tasks. Previously, such task
was submitted to another thread and the main thread waited for its completion.
That involves multiple inter-thread synchronization which is not cheap for
small tasks. Now, such task is processed by the main thread, so no inter-thread
communication is necessary.
Differential revision: https://reviews.llvm.org/D36607
llvm-svn: 311312
There's no functional difference between the AVX512DQ instructions if we're not masking.
This change unifies test checks and removes extra isel entries. Similar was done for subvector insert and extracts recently.
llvm-svn: 311308
Summary:
When extracting the instrumentation map from a binary, we should be able
to recognize the new kinds of instrumentation sleds we've been emitting
with the compiler using -fxray-instrument. This change adds a test for
all the kinds of sleds we currently support (sans the tail-call sled,
which is a bit harder to force in a simple prebuilt input).
Reviewers: kpw, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36819
llvm-svn: 311305
Store operation takes 2 UOps on X86 processors. The exact cost calculation affects several optimization passes including loop unroling.
This change compensates performance degradation caused by https://reviews.llvm.org/D34458 and shows improvements on some benchmarks.
Differential Revision: https://reviews.llvm.org/D35888
llvm-svn: 311285
Added a separate metadata to indicate when the loop
has already been vectorized instead of setting width and count to 1.
Patch written by Divya Shanmughan and Aditya Kumar
Differential Revision: https://reviews.llvm.org/D36220
llvm-svn: 311281
Summary: Support call ABI. For now only Linux C and X86_64_SysV calling conventions supported. Variadic function not supported.
Reviewers: zvi, guyblank, oren_ben_simhon
Reviewed By: oren_ben_simhon
Subscribers: rovka, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D34602
llvm-svn: 311279
Summary:
This updates the Inliner to only add a single Optimization
Remark when Inlining, rather than an Analysis Remark and an
Optimization Remark.
Fixes https://bugs.llvm.org/show_bug.cgi?id=33786
Reviewers: anemet, davidxl, chandlerc
Reviewed By: anemet
Subscribers: haicheng, fhahn, mehdi_amini, dblaikie, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D36054
llvm-svn: 311273
Summary:
The New Pass Manager infrastructure was forgetting to keep around the optimization remark yaml file that the compiler might have been producing. This meant setting the option to '-' for stdout worked, but setting it to a filename didn't give file output (presumably it was deleted because compilation didn't explicitly keep it). This change just ensures that the file is kept if compilation succeeds.
So far I have updated one of the optimization remark output tests to add a version with the new pass manager. It is my intention for this patch to also include changes to all tests that use `-opt-remark-output=` but I wanted to get the code patch ready for review while I was making all those changes.
Fixes https://bugs.llvm.org/show_bug.cgi?id=33951
Reviewers: anemet, chandlerc
Reviewed By: anemet, chandlerc
Subscribers: javed.absar, chandlerc, fhahn, llvm-commits
Differential Revision: https://reviews.llvm.org/D36906
llvm-svn: 311271
We can load the memory VT and check for natural alignment. This also adds a new preferNonTemporalLoad helper that checks the correct subtarget feature based on the load size.
This shrinks the isel table by at least 5000 bytes by allowing more reordering and combining to occur.
llvm-svn: 311266
This is the exact same fix as in SVN r247254. In that commit, the fix was
applied only for isVTRNMask and isVTRN_v_undef_Mask, but the same issue
is present for VZIP/VUZP as well.
This fixes PR33921.
Differential Revision: https://reviews.llvm.org/D36899
llvm-svn: 311258
The tests added in r311254 require a target triple since they are
running through code generation. Fix bot failures by requiring
an x86 target.
llvm-svn: 311257
Summary:
If all the operands of a BUILD_VECTOR extract elements from same vector then split the
vector efficiently based on the maximum vector access index.
Reviewers: zvi, delena, RKSimon, thakis
Reviewed By: RKSimon
Subscribers: chandlerc, eladcohen, llvm-commits
Differential Revision: https://reviews.llvm.org/D35788
llvm-svn: 311255
