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Revision tags: llvmorg-20.1.0, llvmorg-20.1.0-rc3, llvmorg-20.1.0-rc2, llvmorg-20.1.0-rc1, llvmorg-21-init, llvmorg-19.1.7, llvmorg-19.1.6, llvmorg-19.1.5, llvmorg-19.1.4, llvmorg-19.1.3, llvmorg-19.1.2, llvmorg-19.1.1, llvmorg-19.1.0, llvmorg-19.1.0-rc4, llvmorg-19.1.0-rc3, llvmorg-19.1.0-rc2, llvmorg-19.1.0-rc1, llvmorg-20-init, llvmorg-18.1.8, llvmorg-18.1.7, llvmorg-18.1.6, llvmorg-18.1.5, llvmorg-18.1.4, llvmorg-18.1.3, llvmorg-18.1.2, llvmorg-18.1.1, llvmorg-18.1.0, llvmorg-18.1.0-rc4, llvmorg-18.1.0-rc3, llvmorg-18.1.0-rc2, llvmorg-18.1.0-rc1, llvmorg-19-init, llvmorg-17.0.6, llvmorg-17.0.5, llvmorg-17.0.4, llvmorg-17.0.3, llvmorg-17.0.2, llvmorg-17.0.1, llvmorg-17.0.0, llvmorg-17.0.0-rc4, llvmorg-17.0.0-rc3, llvmorg-17.0.0-rc2, llvmorg-17.0.0-rc1, llvmorg-18-init, llvmorg-16.0.6, llvmorg-16.0.5, llvmorg-16.0.4, llvmorg-16.0.3, llvmorg-16.0.2, llvmorg-16.0.1, llvmorg-16.0.0, llvmorg-16.0.0-rc4, llvmorg-16.0.0-rc3, llvmorg-16.0.0-rc2, llvmorg-16.0.0-rc1, llvmorg-17-init, llvmorg-15.0.7, llvmorg-15.0.6, llvmorg-15.0.5, llvmorg-15.0.4, llvmorg-15.0.3, llvmorg-15.0.2, llvmorg-15.0.1, llvmorg-15.0.0, llvmorg-15.0.0-rc3, llvmorg-15.0.0-rc2, llvmorg-15.0.0-rc1, llvmorg-16-init, llvmorg-14.0.6, llvmorg-14.0.5, llvmorg-14.0.4 |
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e9a1c82d |
| 11-May-2022 |
Nikita Popov <[email protected]> |
[SCEVExpander] Expand umin_seq using freeze
%x umin_seq %y is currently expanded to %x == 0 ? 0 : umin(%x, %y).
This patch changes the expansion to umin(%x, freeze %y) instead
(https://alive2.llvm.o
[SCEVExpander] Expand umin_seq using freeze
%x umin_seq %y is currently expanded to %x == 0 ? 0 : umin(%x, %y).
This patch changes the expansion to umin(%x, freeze %y) instead
(https://alive2.llvm.org/ce/z/wujUhp).
The motivation for this change are the test cases affected by
D124910, where the freeze expansion ultimately produces better
optimization results. This is largely because
`(%x umin_seq %y) == %x` is a common expansion pattern, which
reliably optimizes in freeze representation, but only sometimes
with the zero comparison (in particular, if %x == 0 can fold to
something else, we generally won't be able to cover reasonable
code from this.)
Differential Revision: https://reviews.llvm.org/D125372
show more ...
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Revision tags: llvmorg-14.0.3, llvmorg-14.0.2, llvmorg-14.0.1, llvmorg-14.0.0, llvmorg-14.0.0-rc4, llvmorg-14.0.0-rc3, llvmorg-14.0.0-rc2, llvmorg-14.0.0-rc1, llvmorg-15-init, llvmorg-13.0.1, llvmorg-13.0.1-rc3, llvmorg-13.0.1-rc2 |
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| #
76a0abbc |
| 11-Jan-2022 |
Roman Lebedev <[email protected]> |
[SCEV] Reenable umin_seq support and fix the `computeSCEVAtScope()`
This reverts commit f62f47f5e1f641b41d3b7d593c058ebec2883534.
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f62f47f5 |
| 11-Jan-2022 |
Philip Reames <[email protected]> |
Partial revert of 82fb4f4
Two crashes have been reported. This change disables the new logic while leaving the new node in tree. Hopefully, that's enough to allow investigation without breakage wh
Partial revert of 82fb4f4
Two crashes have been reported. This change disables the new logic while leaving the new node in tree. Hopefully, that's enough to allow investigation without breakage while avoiding massive churn.
show more ...
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| #
82fb4f4b |
| 10-Jan-2022 |
Roman Lebedev <[email protected]> |
[SCEV] Sequential/in-order `UMin` expression
As discussed in https://github.com/llvm/llvm-project/issues/53020 / https://reviews.llvm.org/D116692,
SCEV is forbidden from reasoning about 'backedge ta
[SCEV] Sequential/in-order `UMin` expression
As discussed in https://github.com/llvm/llvm-project/issues/53020 / https://reviews.llvm.org/D116692,
SCEV is forbidden from reasoning about 'backedge taken count'
if the branch condition is a poison-safe logical operation,
which is conservatively correct, but is severely limiting.
Instead, we should have a way to express those
poison blocking properties in SCEV expressions.
The proposed semantics is:
```
Sequential/in-order min/max SCEV expressions are non-commutative variants
of commutative min/max SCEV expressions. If none of their operands
are poison, then they are functionally equivalent, otherwise,
if the operand that represents the saturation point* of given expression,
comes before the first poison operand, then the whole expression is not poison,
but is said saturation point.
```
* saturation point - the maximal/minimal possible integer value for the given type
The lowering is straight-forward:
```
compare each operand to the saturation point,
perform sequential in-order logical-or (poison-safe!) ordered reduction
over those checks, and if reduction returned true then return
saturation point else return the naive min/max reduction over the operands
```
https://alive2.llvm.org/ce/z/Q7jxvH (2 ops)
https://alive2.llvm.org/ce/z/QCRrhk (3 ops)
Note that we don't need to check the last operand: https://alive2.llvm.org/ce/z/abvHQS
Note that this is not commutative: https://alive2.llvm.org/ce/z/FK9e97
That allows us to handle the patterns in question.
Reviewed By: nikic, reames
Differential Revision: https://reviews.llvm.org/D116766
show more ...
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| #
6a563e25 |
| 06-Jan-2022 |
Roman Lebedev <[email protected]> |
[NFC][SCEV][IndVars] Add more tests for exit count w/ `select`
See https://github.com/llvm/llvm-project/issues/53020
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