The IRSimilarityCandidate is a container to hold a region of
IRInstructions and offer interfaces for the starting instruction, ending
instruction, parent function, length. It also assigns a global value
number for each unique instance of a value in the region.
It also contains an interface to compare two IRSimilarity as to whether
they have the same sequence of similar instructions.
Tests for whether the instructions are similar are found in
unittests/Analysis/IRSimilarityIdentifierTest.cpp.
Differential Revision: https://reviews.llvm.org/D86970
Currently these predicates are ignored, yet their handling is
pretty simple. I could not find a single test where it would
actually change something, but it's only because isImpliedCondOperands
is not smart enough to prove it further on. Yet the situation when
we come there with `less` predicate is pretty common.
Differential Revision: https://reviews.llvm.org/D87890
Reviewed By: fhahn
Changes TTI function getIntImmCostInst to take an additional Instruction parameter,
which enables us to be able to check it is part of a min(max())/max(min()) pattern that will match SSAT.
We can then mark the constant used as free to prevent it being hoisted so SSAT can still be generated.
Required minor changes in some non-ARM backends to allow for the optional parameter to be included.
Differential Revision: https://reviews.llvm.org/D87457
This commit was originally because it was suspected to cause a crash,
but a reproducer did not surface.
A crash that was exposed by this change was fixed in 1d8f2e5292.
This reverts the revert commit 0581c0b0ee.
InstCombine likes to canonicalize comparisons of the form
X == C || X == C+1 into (X & -2) == C'. Make sure LVI can still
recover the value range from this. Can of course also be useful
for proper mask comparisons.
For the sake of clarity, the implementation goes through KnownBits
to compute the range.
Rewrite this in a way where the core logic is in a separate
function, that is invoked with swapped operands. This makes it
easier to add handling for additional icmp patterns.
The output here may not be optimal (yet), but it should be
consistent for commuted operands (it was not before) and
correct. We can do better by checking FMF and NaN if needed.
Code in InstSimplify generally assumes that we have already
folded code like this, so it was not handling 2 constant
inputs by commuting consistently.
The IRInstructionData structs are a different representation of the
program. This list treats the program as if it was "flattened" and
the only parent is this list. This lets us easily create ranges of
instructions.
Differential Revision: https://reviews.llvm.org/D86969
This patch extends SCEVParameterRewriter to support rewriting unknown
epxressions to arbitrary SCEV expressions. It will be used by further
patches.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D67176
This introduces the IRInstructionMapper, and the associated wrapper for
instructions, IRInstructionData, that maps IR level Instructions to
unsigned integers.
Mapping is done mainly by using the "isSameOperationAs" comparison
between two instructions. If they return true, the opcode, result type,
and operand types of the instruction are used to hash the instruction
with an unsigned integer. The mapper accepts instruction ranges, and
adds each resulting integer to a list, and each wrapped instruction to
a separate list.
At present, branches, phi nodes are not mapping and exception handling
is illegal. Debug instructions are not considered.
The different mapping schemes are tested in
unittests/Analysis/IRSimilarityIdentifierTest.cpp
Recommit of: b04c1a9d31
Differential Revision: https://reviews.llvm.org/D86968
As @efriedma pointed out in D86301, this "not equal to 0 check" of
get.active.lane.mask's second operand needs to live here in Lint and not the
Verifier.
Differential Revision: https://reviews.llvm.org/D87228
This introduces the IRInstructionMapper, and the associated wrapper for
instructions, IRInstructionData, that maps IR level Instructions to
unsigned integers.
Mapping is done mainly by using the "isSameOperationAs" comparison
between two instructions. If they return true, the opcode, result type,
and operand types of the instruction are used to hash the instruction
with an unsigned integer. The mapper accepts instruction ranges, and
adds each resulting integer to a list, and each wrapped instruction to
a separate list.
At present, branches, phi nodes are not mapping and exception handling
is illegal. Debug instructions are not considered.
The different mapping schemes are tested in
unittests/Analysis/IRSimilarityIdentifierTest.cpp
Differential Revision: https://reviews.llvm.org/D86968
Really it should be named print<alias-sets>, but for the sake of
changing fewer tests, added a TODO to rename after NPM switch and test
cleanup.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D87713
If SimplifyWithOpReplaced() cannot simplify the value, null should
be returned. Make sure this really does happen in all cases,
including those where SimplifyBinOp() returns the original value.
This does not matter for existing users, but does mattter for
D87480, which would go into an infinite loop otherwise.
When adding a new function via addNewFunctionIntoRefSCC(), it creates a
new node and immediately populates the edges. Since populateSlow() calls
G->get() on all referenced functions, it will create a node (but not
populate it) for functions that haven't yet been added. If we add two
mutually recursive functions, the assert that the node should never have
been created will fire when the second function is added. So here we
remove that assert since the node may have already been created (but not
yet populated).
createNode() is only called from addNewFunctionInto{,Ref}SCC().
https://bugs.llvm.org/show_bug.cgi?id=47502
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D87623
If the constant operand is the opposite of the min/max value,
then the result must be the other value.
This is based on the similar codegen transform proposed in:
D87571
This patch adds a isConditionImplied function that
takes a constraint and returns true if the constraint
is implied by the current constraints in the system.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D84545
This patch recommits "[ConstraintSystem] Add helpers to deal with linear constraints."
(it reverts the revert commit 8da6ae4ce1).
The reason for the revert was using __builtin_multiply_overflow, which
is not available for all compilers. The patch has been updated to use
MulOverflow from MathExtras.h
1ce82015f6 added a fix to restrict phi optimizations after phi
translations. But the current use of performedPhiTranslation only
checked whether phi translation happened for the first iterator and
missed cases where phi translations happens at subsequent
iterators/upwards defs.
This patch changes upward_defs_iteartor to take a pointer to a bool, so
we can easily ensure the final value includes all visited defs, while
still being able to conveniently use it with make_range & co.
As discussed in the sibling codegen functionality patch D87571,
this transform was created with D52766, but it is not correct.
The incorrect test diffs were missed during review, but the
'TODO' comment about this functionality was still in the code -
we need 'nnan' to enable this fold.
This allows the backend to tell the vectorizer to produce inloop
reductions through a TTI hook.
For the moment on ARM under MVE this means allowing integer add
reductions of the correct size. In the future this can include integer
min/max too, under -Os.
Differential Revision: https://reviews.llvm.org/D75512
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.
This is a followup to D86834, which partially fixed this issue in
InstSimplify. However, InstCombine repeats the same transform while
dropping poison flags -- which does not cover cases where poison is
introduced in some other way.
The fix here is a bit more comprehensive, because things are quite
entangled, and it's hard to only partially address it without
regressing optimization. There are really two changes here:
* Export the SimplifyWithOpReplaced API from InstSimplify, with an
added AllowRefinement flag. For replacements inside the TrueVal
we don't actually care whether refinement occurs or not, the
replacement is always legal. This part of the transform is now
done in InstSimplify only. (It should be noted that the current
AllowRefinement check is not sufficient -- that's an issue we
need to address separately.)
* Change the InstCombine fold to work by temporarily dropping
poison generating flags, running the fold and then restoring the
flags if it didn't work out. This will ensure that the InstCombine
fold is correct as long as the InstSimplify fold is correct.
Differential Revision: https://reviews.llvm.org/D87445
This patch introduces a new ConstraintSystem class, that maintains a set
of linear constraints and uses Fourier–Motzkin elimination to eliminate
constraints to check if there are solutions for the system.
It also adds a convert-constraint-log-to-z3.py script, which can parse
the debug output of the constraint system and convert it to a python
script that feeds the constraints into Z3 and checks if it produces the
same result as the LLVM implementation. This is for verification
purposes.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D84544
Sanjay Patel