(This reverts commit a5e0194709c40212694370e0ea789a1ca14548b5, and
corrects author).
Rename the pass to be able to extend it to function properties other than inliner features.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D82044
Rename the pass to be able to extend it to function properties other than inliner features.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D82044
For a long time, the InstCombine pass handled target specific
intrinsics. Having target specific code in general passes was noted as
an area for improvement for a long time.
D81728 moves most target specific code out of the InstCombine pass.
Applying the target specific combinations in an extra pass would
probably result in inferior optimizations compared to the current
fixed-point iteration, therefore the InstCombine pass resorts to newly
introduced functions in the TargetTransformInfo when it encounters
unknown intrinsics.
The patch should not have any effect on generated code (under the
assumption that code never uses intrinsics from a foreign target).
This introduces three new functions:
TargetTransformInfo::instCombineIntrinsic
TargetTransformInfo::simplifyDemandedUseBitsIntrinsic
TargetTransformInfo::simplifyDemandedVectorEltsIntrinsic
A few target specific parts are left in the InstCombine folder, where
it makes sense to share code. The largest left-over part in
InstCombineCalls.cpp is the code shared between arm and aarch64.
This allows to move about 3000 lines out from InstCombine to the targets.
Differential Revision: https://reviews.llvm.org/D81728
This assert was added to verify assumption that GEP's SCEV will be of pointer type,
basing on fact that it should be a SCEVAddExpr with (at least) last operand being
pointer. Two notes:
- GEP's SCEV does not have to be a SCEVAddExpr after all simplifications;
- In current state, GEP's SCEV does not have to have at least one pointer operands
(all of them can become int during the transforms).
However, we might want to be at a point where it is true. We are currently removing
this assert and will try to enumerate the cases where "is pointer" notion might be
lost during the transforms. When all of them are fixed, we can return it.
Differential Revision: https://reviews.llvm.org/D84294
Reviewed By: lebedev.ri
.. in isGuaranteedNotToBeUndefOrPoison.
This caused early exit of isGuaranteedNotToBeUndefOrPoison, making it return
imprecise result.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D84251
Outside of compiler-rt (where it's arguably an anti-pattern too),
LLVM tries to keep its build files as simple as possible. See e.g.
llvm/docs/SupportLibrary.rst, "Code Organization".
Differential Revision: https://reviews.llvm.org/D84243
We can sometimes get into the situation where the operand to a vctp
intrinsic becomes constant, such as after a loop is fully unrolled. This
adds the constant folding needed for them, allowing them to simplify
away and hopefully simplifying remaining instructions.
Differential Revision: https://reviews.llvm.org/D84110
Summary:
This is the InlineAdvisor used in 'development' mode. It enables two
scenarios:
- loading models via a command-line parameter, thus allowing for rapid
training iteration, where models can be used for the next exploration
phase without requiring recompiling the compiler. This trades off some
compilation speed for the added flexibility.
- collecting training logs, in the form of tensorflow.SequenceExample
protobufs. We generate these as textual protobufs, which simplifies
generation and testing. The protobufs may then be readily consumed by a
tensorflow-based training algorithm.
To speed up training, training logs may also be collected from the
'default' training policy. In that case, this InlineAdvisor does not
use a model.
RFC: http://lists.llvm.org/pipermail/llvm-dev/2020-April/140763.html
Reviewers: jdoerfert, davidxl
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83733
This allows tracking the in-memory type of a pointer argument to a
function for ABI purposes. This is essentially a stripped down version
of byval to remove some of the stack-copy implications in its
definition.
This includes the base IR changes, and some tests for places where it
should be treated similarly to byval. Codegen support will be in a
future patch.
My original attempt at solving some of these problems was to repurpose
byval with a different address space from the stack. However, it is
technically permitted for the callee to introduce a write to the
argument, although nothing does this in reality. There is also talk of
removing and replacing the byval attribute, so a new attribute would
need to take its place anyway.
This is intended avoid some optimization issues with the current
handling of aggregate arguments, as well as fixes inflexibilty in how
frontends can specify the kernel ABI. The most honest representation
of the amdgpu_kernel convention is to expose all kernel arguments as
loads from constant memory. Today, these are raw, SSA Argument values
and codegen is responsible for turning these into loads.
Background:
There currently isn't a satisfactory way to represent how arguments
for the amdgpu_kernel calling convention are passed. In reality,
arguments are passed in a single, flat, constant memory buffer
implicitly passed to the function. It is also illegal to call this
function in the IR, and this is only ever invoked by a driver of some
kind.
It does not make sense to have a stack passed parameter in this
context as is implied by byval. It is never valid to write to the
kernel arguments, as this would corrupt the inputs seen by other
dispatches of the kernel. These argumets are also not in the same
address space as the stack, so a copy is needed to an alloca. From a
source C-like language, the kernel parameters are invisible.
Semantically, a copy is always required from the constant argument
memory to a mutable variable.
The current clang calling convention lowering emits raw values,
including aggregates into the function argument list, since using
byval would not make sense. This has some unfortunate consequences for
the optimizer. In the aggregate case, we end up with an aggregate
store to alloca, which both SROA and instcombine turn into a store of
each aggregate field. The optimizer never pieces this back together to
see that this is really just a copy from constant memory, so we end up
stuck with expensive stack usage.
This also means the backend dictates the alignment of arguments, and
arbitrarily picks the LLVM IR ABI type alignment. By allowing an
explicit alignment, frontends can make better decisions. For example,
there's real no advantage to an aligment higher than 4, so a frontend
could choose to compact the argument layout. Similarly, there is a
high penalty to using an alignment lower than 4, so a frontend could
opt into more padding for small arguments.
Another design consideration is when it is appropriate to expose the
fact that these arguments are all really passed in adjacent
memory. Currently we have a late IR optimization pass in codegen to
rewrite the kernel argument values into explicit loads to enable
vectorization. In most programs, unrelated argument loads can be
merged together. However, exposing this property directly from the
frontend has some disadvantages. We still need a way to track the
original argument sizes and alignments to report to the driver. I find
using some side-channel, metadata mechanism to track this
unappealing. If the kernel arguments were exposed as a single buffer
to begin with, alias analysis would be unaware that the padding bits
betewen arguments are meaningless. Another family of problems is there
are still some gaps in replacing all of the available parameter
attributes with metadata equivalents once lowered to loads.
The immediate plan is to start using this new attribute to handle all
aggregate argumets for kernels. Long term, it makes sense to migrate
all kernel arguments, including scalars, to be passed indirectly in
the same manner.
Additional context is in D79744.
The getAllOnesValue can only handle things that are bitcast from a
ConstantInt, while here we bitcast through a pointer, so we may see more
complex objects (like Array or Struct).
Differential Revision: https://reviews.llvm.org/D83870
This patch
- adds `canCreateUndefOrPoison`
- refactors `canCreatePoison` so it can deal with constantexprs
`canCreateUndefOrPoison` will be used at D83926.
Reviewed By: nikic, jdoerfert
Differential Revision: https://reviews.llvm.org/D84007
Summary:
This change added a new inline advisor that takes optimization remarks from previous inlining as input, and provides the decision as advice so current inlining can replay inline decisions of a different compilation. Dwarf inline stack with line and discriminator is used as anchor for call sites including call context. The change can be useful for Inliner tuning as it provides a channel to allow external input for tweaking inline decisions. Existing alternatives like alwaysinline attribute is per-function, not per-callsite. Per-callsite inline intrinsic can be another solution (not yet existing), but it's intrusive to implement and also does not differentiate call context.
A switch -sample-profile-inline-replay=<inline_remarks_file> is added to hook up the new inline advisor with SampleProfileLoader's inline decision for replay. Since SampleProfileLoader does top-down inlining, inline decision can be specialized for each call context, hence we should be able to replay inlining accurately. However with a bottom-up inliner like CGSCC inlining, the replay can be limited due to lack of specialization for different call context. Apart from that limitation, the new inline advisor can still be used by regular CGSCC inliner later if needed for tuning purpose.
Subscribers: mgorny, aprantl, hiraditya, llvm-commits
Tags: #llvm
Resubmit for https://reviews.llvm.org/D84086
This is a step towards trying to remove unnecessary FP compares
with infinity when compiling with -ffinite-math-only or similar.
I'm intentionally not checking FMF on the fcmp itself because
I'm assuming that will go away eventually.
The analysis part of this was added with rGcd481136 for use with
isKnownNeverNaN. Similarly, that could be an enhancement here to
get predicates like 'one' and 'ueq'.
Differential Revision: https://reviews.llvm.org/D84035
as it is failing the inline-replay.ll test as well as sanitizers/Werror
from returning a stack local variable.
This reverts commit 029946b112684c27b27f7c2d7554f22b33ae1e0b.
Summary:
This change added a new inline advisor that takes optimization remarks for previous inlining as input, and provide the decision as advice so current inlining can replay inline decision of a different compilation. Dwarf inline stack with line and discriminator is used as anchor for call sites. The change can be useful for Inliner tuning.
A switch -sample-profile-inline-replay=<inline_remarks_file> is added to hook up the new inliner advisor with SampleProfileLoader's inline decision for replay. The new inline advisor can also be used by regular CGSCC inliner later if needed.
Reviewers: davidxl, mtrofin, wmi, hoy
Subscribers: aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83743
due to the performance bugs filed in https://bugs.llvm.org/show_bug.cgi?id=46753.
An SROA change soon may obviate some of these problems.
This reverts commit 8d09f20798ac180b1749276bff364682ce0196ab.
Many tests use opt's -analyze feature, which does not translate well to
NPM and has better alternatives. The alternative here is to explicitly
add a pass that calls ScalarEvolution::print().
The legacy pass manager RUNs aren't changing, but they are now pinned to
the legacy pass manager. For each legacy pass manager RUN, I added a
corresponding NPM RUN using the 'print<scalar-evolution>' pass. For
compatibility with update_analyze_test_checks.py and existing test
CHECKs, 'print<scalar-evolution>' now prints what -analyze prints per
function.
This was generated by the following Python script and failures were
manually fixed up:
import sys
for i in sys.argv:
with open(i, 'r') as f:
s = f.read()
with open(i, 'w') as f:
for l in s.splitlines():
if "RUN:" in l and ' -analyze ' in l and '\\' not in l:
f.write(l.replace(' -analyze ', ' -analyze -enable-new-pm=0 '))
f.write('\n')
f.write(l.replace(' -analyze ', ' -disable-output ').replace(' -scalar-evolution ', ' "-passes=print<scalar-evolution>" ').replace(" | ", " 2>&1 | "))
f.write('\n')
else:
f.write(l)
There are a couple failures still in ScalarEvolution under NPM, but
those are due to other unrelated naming conflicts.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D83798
When the byref attribute is added, there will need to be two similar
functions for the existing cases which have an associate value copy,
and byref which does not. Most, but not all of the existing uses will
use the existing version.
The associated size function added by D82679 also needs to
contextually differ, and will help eliminate a few places still
relying on pointee element types.
The IR doesn't have a proper concept of invalid pointers, and "null"
constants are just all zeros (though it really needs one).
I think it's not possible to break this for AMDGPU due to the copy
semantics of byval. If you have an original stack object at 0, the
byval copy will be placed above it so I don't think it's really
possible to hit a 0 address.
As shown in D82998, the basic-aa-recphi option can cause miscompiles for
gep's with negative constants. The option checks for recursive phi, that
recurse through a contant gep. If it finds one, it performs aliasing
calculations using the other phi operands with an unknown size, to
specify that an unknown number of elements after the initial value are
potentially accessed. This works fine expect where the constant is
negative, as the size is still considered to be positive. So this patch
expands the check to make sure that the constant is also positive.
Differential Revision: https://reviews.llvm.org/D83576
This reverts most of the following patches due to reports of miscompiles.
I've left the added test cases with comments updated to be FIXMEs.
1cf6f210a2e [IR] Disable select ? C : undef -> C fold in ConstantFoldSelectInstruction unless we know C isn't poison.
469da663f2d [InstSimplify] Re-enable select ?, undef, X -> X transform when X is provably not poison
122b0640fc9 [InstSimplify] Don't fold vectors of partial undef in SimplifySelectInst if the non-undef element value might produce poison
ac0af12ed2f [InstSimplify] Add test cases for opportunities to fold select ?, X, undef -> X when we can prove X isn't poison
9b1e95329af [InstSimplify] Remove select ?, undef, X -> X and select ?, X, undef -> X transforms
Summary:
This change avoids exposing tensorflow types when including TFUtils.h.
They are just an implementation detail, and don't need to be used
directly when implementing an analysis requiring ML model evaluation.
The TFUtils APIs, while generically typed, are still not exposed unless
the tensorflow C library is present, as they currently have no use
otherwise.
Reviewers: mehdi_amini, davidxl
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83843
Since D82572, we keep "reference" edges for callback call sites. While
not strictly necessary they can improve the traversal order. However, we
did not update them properly in case a pass removed the callback call
site which caused a verification error (PR46687). With this patch we
update these reference edges properly during the invocation of
`CallGraphSCCPass::RefreshCallGraph` in non-checking mode.
Reviewed By: sdmitriev
Differential Revision: https://reviews.llvm.org/D83718
Summary:
Ignore callback uses when adding a callback function
in the CallGraph. Callback functions are typically
created when outlining, e.g. for OpenMP, so they have
internal scope and linkage. They should not be added
to the ExternalCallingNode since they are only callable
by the specified caller function at creation time.
A CGSCC pass, such as OpenMPOpt, may need to update
the CallGraph by adding a new outlined callback function.
Without ignoring callback uses, adding breaks CGSCC
pass restrictions and results to a broken CallGraph.
Reviewers: jdoerfert
Subscribers: hiraditya, sstefan1, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83370
Summary:
Add debug counter and stats counter to assume queries and assume builder
here is the collected stats on a build of check-llvm + check-clang.
"assume-builder.NumAssumeBuilt": 2720879,
"assume-builder.NumAssumesMerged": 761396,
"assume-builder.NumAssumesRemoved": 1576212,
"assume-builder.NumBundlesInAssumes": 6518809,
"assume-queries.NumAssumeQueries": 85566380,
"assume-queries.NumUsefullAssumeQueries": 2727360,
the NumUsefullAssumeQueries stat is actually pessimistic because in a few places queries
ask to keep providing information to try to get better information. and this isn't counted
as a usefull query evem tho it can be usefull
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83506
This fixes warnings raised by Clang's new -Wsuggest-override, in preparation for enabling that warning in the LLVM build. This patch also removes the virtual keyword where redundant, but only in places where doing so improves consistency within a given file. It also removes a couple unnecessary virtual destructor declarations in derived classes where the destructor inherited from the base class is already virtual.
Differential Revision: https://reviews.llvm.org/D83709
Here we teach the ConstantFolding analysis pass that it is not legal to
replace a load of a bitcast constant (having a non-integral addrspace)
with a bitcast of the value of that constant (with a different
non-integral addrspace).
But also teach it that certain bit patterns are always known and
convertable (a fact it already uses elsewhere). This required us to also
fix a globalopt test, since, after this change, LLVM is able to realize
that the test actually is a valid transform (NULL is always a known
bit-pattern) and so it doesn't need to emit the failure remarks for it.
Also simplify some of the negative tests for transforms by avoiding a
type change in their bitcast, and add positive versions of the same
tests, to show that they otherwise should work.
Differential Revision: https://reviews.llvm.org/D59730
This reverts commit 9908a3b9f521c954cbf6adcec35b14b2f6c8da49.
The fix was to exclude the content of TFUtils.h (automatically
included in the LLVM_Analysis module, when LLVM_ENABLE_MODULES is enabled).
Differential Revision: https://reviews.llvm.org/D82817
Summary:
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".
As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.
Reviewers: hfinkel, xbolva00, lebedev.ri, nikic, rjmccall, spatel, jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: thopre, yamauchi, kuter, fhahn, merge_guards_bot, hiraditya, bollu, rkruppe, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71739
This is in preparation for the 'development' mode advisor. We currently
want to track what the default policy's decision would have been, this
refactoring makes it easier to do that.
Also compacted the checkpoints (variables) to one file (plus the index).
This reduces the binary model files to just the variables and their
index. The index is very small. The variables are serialized float
arrays. When updated through training, the changes are very likely
unlocalized, so there's very little value in them being anything else
than binary.
