18 Commits

Author SHA1 Message Date
Andrew Litteken
ba29899541 [IRSim] Letting call instructions be legal for similarity identification.
Here we let non-intrinsic calls be considered legal and valid for
similarity only if the call is not indirect, and has a name.

For two calls to be considered similar, they must have the same name,
the same function types, and the same set of parameters, including tail
calls and calling conventions.

Tests are found in unittests/Analysis/IRSimilarityIdentifierTest.cpp.

Reviewers: jroelofs, paquette

Differential Revision: https://reviews.llvm.org/D87312
2020-12-31 20:52:45 -06:00
Andrew Litteken
f26f3634db [IRSim] Letting gep instructions be legal for similarity identification.
GetElementPtr instructions require the extra check that all operands
after the first must only be constants and be exactly the same to be
considered similar.

Tests are found in unittests/Analysis/IRSimilarityIdentifierTest.cpp.
2020-12-31 14:41:14 -06:00
Andrew Litteken
c73c69986e [IRSim] Adding support for isomorphic predicates
Some predicates, can be considered the same as long as the operands are
flipped. For example, a > b gives the same result as b > a. This maps
instructions in a greater than form, to their appropriate less than
form, swapping the operands in the IRInstructionData only, allowing for
more flexible matching.

Tests:

llvm/test/Transforms/IROutliner/outlining-isomorphic-predicates.ll
llvm/unittests/Analysis/IRSimilarityIdentifierTest.cpp

Reviewers: jroelofs, paquette

Recommit of commit 050392660249c70c00e909ae4a7151ba2c766235

Differential Revision: https://reviews.llvm.org/D87310
2020-12-23 19:42:35 -06:00
Andrew Litteken
00de87e487 Revert "[IRSim] Adding support for isomorphic predicates"
Reverting due to unit test errors between commits.

This reverts commit 050392660249c70c00e909ae4a7151ba2c766235.
2020-12-23 15:14:19 -06:00
Andrew Litteken
4270a97faa [IRSim] Adding support for isomorphic predicates
Some predicates, can be considered the same as long as the operands are
flipped. For example, a > b gives the same result as b > a. This maps
instructions in a greater than form, to their appropriate less than
form, swapping the operands in the IRInstructionData only, allowing for
more flexible matching.

Tests:

llvm/test/Transforms/IROutliner/outlining-isomorphic-predicates.ll
llvm/unittests/Analysis/IRSimilarityIdentifierTest.cpp

Reviewers: jroelofs, paquette

Differential Revision: https://reviews.llvm.org/D87310
2020-12-23 15:02:00 -06:00
Andrew Litteken
ec30ab6369 [IRSim] Adding commutativity matching to structure checking
Certain instructions, such as adds and multiplies can have the operands
flipped and still be considered the same. When we are analyzing
structure, this gives slightly more flexibility to create a mapping from
one region to another. We can add both operands in a corresponding
instruction to an operand rather than just the exact match. We then try
to eliminate items from the set, until there is only one valid mapping
between the regions of code.

We do this for adds, multiplies, and equality checking. However, this is
not done for floating point instructions, since the order can still
matter in some cases.

Tests:

llvm/test/Transforms/IROutliner/outlining-commutative-fp.ll
llvm/test/Transforms/IROutliner/outlining-commutative.ll
llvm/unittests/Analysis/IRSimilarityIdentifierTest.cpp

Reviewers: jroelofs, paquette

Differential Revision: https://reviews.llvm.org/D87311
2020-12-23 15:02:00 -06:00
Alexander Belyaev
8da6b41423 [llvm] Use instead of in IRSimilarityIdentifierTest.cpp. 2020-09-24 11:28:26 +02:00
Andrew Litteken
b786a09fd0 [IRSim] Adding a basic similarity identifier.
This takes the mapped instructions from the IRInstructionMapper, and
passes it to the Suffix Tree to find the repeated substrings.  Within
each set of repeated substrings, the IRSimilarityCandidates are compared
against one another for structure, and ensuring that the operands in the
instructions are used in the same way.  Each of these structurally
similarity IRSimilarityCandidates are contained in a SimilarityGroup.

Tests checking for identifying identity of structure, different
isomorphic structure, and different
nonisomoprhic structure are found in
unittests/Analysis/IRSimilarityIdentifierTest.cpp.

Differential Revision: https://reviews.llvm.org/D86972
2020-09-24 02:05:25 -05:00
Andrew Litteken
3d12233786 [IRSim] Adding structural comparison to IRSimilarityCandidate.
Just because sequences of instructions are similar to one another,
doesn't mean they are doing the same thing.

This introduces a structural check for the IRSimilarityCandidate that
compares two IRSimilarityCandidates against one another, and in each
instruction creates a mapping between the operands and results, or
checks that the existing mapping is valid.  If this check passes, it
means we have structurally similar IRSimilarityCandidates.

Tests for whether the candidates are found in
unittests/Analysis/IRSimilarityIdentifierTest.cpp.

Recommit of: b27db2bb68163fa5bcb4a8f631a305eb5adb44e5 for Differential
URL.

Differential Revision: https://reviews.llvm.org/D86971
2020-09-23 22:42:30 -05:00
Andrew Litteken
d5678d1cef Revert "[IRSim] Adding structural comparison to IRSimilarityCandidate."
This reverts commit b27db2bb68163fa5bcb4a8f631a305eb5adb44e5.
2020-09-23 22:40:37 -05:00
Andrew Litteken
5b31a525de [IRSim] Adding structural comparison to IRSimilarityCandidate.
Just because sequences of instructions are similar to one another,
doesn't mean they are doing the same thing.

This introduces a structural check for the IRSimilarityCandidate that
compares two IRSimilarityCandidates against one another, and in each
instruction creates a mapping between the operands and results, or
checks that the existing mapping is valid.  If this check passes, it
means we have structurally similar IRSimilarityCandidates.

Tests for whether the candidates are found in
unittests/Analysis/IRSimilarityIdentifierTest.cpp.
2020-09-23 22:31:12 -05:00
Andrew Litteken
b8f3d293f1 [IRSim] Adding IRSimilarityCandidate that contains a region of IRInstructionData.
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.

Recommit of: 4944bb190fed8861d4d043eaf45e3c1e12aa2dc5

Differential Revision: https://reviews.llvm.org/D86970
2020-09-23 13:43:34 -05:00
Andrew Litteken
e070ab13db Revert "[IRSim] Adding IRSimilarityCandidate that contains a region of IRInstructionData."
This reverts commit 4944bb190fed8861d4d043eaf45e3c1e12aa2dc5.
2020-09-22 21:02:34 -05:00
Andrew Litteken
f6a16cfb40 [IRSim] Adding IRSimilarityCandidate that contains a region of IRInstructionData.
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
2020-09-22 18:42:31 -05:00
Andrew Litteken
c53dab65b4 [IRSim] Adding ilist for IRInstructionData.
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
2020-09-19 00:18:39 -05:00
Andrew Litteken
f7aaee70de [IRSim] Adding IR Instruction Mapper
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: b04c1a9d3127730c05e8a22a0e931a12a39528df

Differential Revision: https://reviews.llvm.org/D86968
2020-09-17 14:06:16 -05:00
Stella Stamenova
0778e74e6b Revert "[IRSim] Adding IR Instruction Mapper"
This reverts commit b04c1a9d3127730c05e8a22a0e931a12a39528df.
2020-09-16 20:00:43 -07:00
Andrew Litteken
5831702c50 [IRSim] Adding IR Instruction Mapper
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
2020-09-16 20:49:21 -05:00