Follow up to the discussion from #75258, and serves as an alternate
solution for #74670.
Set the location to Unknown for deduplicated / moved / materialized
constants by OperationFolder. This makes sure that the folded constants
don't end up with an arbitrary location of one of the original ops that
became it, and that hoisted ops don't confuse the stepping order.
If the loop bound is not initialized, the analysis crashed, as it only checked for nullity. Also checking for initialization fixes the issue.
Signed-off-by: Victor Perez <victor.perez@codeplay.com>
Co-authored-by: Tsang, Whitney <whitney.tsang@intel.com>
The constructor of `OperationFolder` takes a listener. Therefore, the remaining API should not take any builder/rewriters. This could lead to double notifications in case a listener is attached to the builder/rewriter.
As an internal cleanup, `OperationFolder` now has an `IRRewriter` instead of a `RewriterBase::Listener`. In most cases, `OperationFolder` no longer has to notify/deal with listeners. This is done by the rewriter.
Differential Revision: https://reviews.llvm.org/D146134
Currently, for sparse analyses, we always store a `Optional<ValueT>` in each lattice element. When it's `None`, we consider the lattice element as `uninitialized`.
However:
* Not all lattices have an `uninitialized` state. For example, `Executable` and `PredecessorState` have default values so they are always initialized.
* In dense analyses, we don't have the concept of an `uninitialized` state.
Given these inconsistencies, this patch removes `Lattice::isUninitialized()`. Individual analysis states are now default-constructed. If the default state of an analysis can be considered as "uninitialized" then this analysis should implement the following logic:
* Special join rule: `join(uninitialized, any) == any`.
* Special bail out logic: if any of the input states is uninitialized, exit the transfer function early.
Depends On D132086
Reviewed By: Mogball
Differential Revision: https://reviews.llvm.org/D132800
Integer range inference has been swapped to the new framework. The integer value range lattices automatically updates the corresponding constant value on update.
Depends on D127173
Reviewed By: krzysz00, rriddle
Differential Revision: https://reviews.llvm.org/D128866
This reverts commit 4e5ce2056e3e85f109a074e80bdd23a10ca2bed9.
This relands commit 1350c9887dca5ba80af8e3c1e61b29d6696eb240.
Reinstates the range analysis with the build issue fixed.
Differential Revision: https://reviews.llvm.org/D126926
This commit defines a dataflow analysis for integer ranges, which
uses a newly-added InferIntRangeInterface to compute the lower and
upper bounds on the results of an operation from the bounds on the
arguments. The range inference is a flow-insensitive dataflow analysis
that can be used to simplify code, such as by statically identifying
bounds checks that cannot fail in order to eliminate them.
The InferIntRangeInterface has one method, inferResultRanges(), which
takes a vector of inferred ranges for each argument to an op
implementing the interface and a callback allowing the implementation
to define the ranges for each result. These ranges are stored as
ConstantIntRanges, which hold the lower and upper bounds for a
value. Bounds are tracked separately for the signed and unsigned
interpretations of a value, which ensures that the impact of
arithmetic overflows is correctly tracked during the analysis.
The commit also adds a -test-int-range-inference pass to test the
analysis until it is integrated into SCCP or otherwise exposed.
Finally, this commit fixes some bugs relating to the handling of
region iteration arguments and terminators in the data flow analysis
framework.
Depends on D124020
Depends on D124021
Reviewed By: rriddle, Mogball
Differential Revision: https://reviews.llvm.org/D124023