add simplification rule for at(x, offset) = ""
Introducing j just postpones some rewrites that prevent useful simplifications. Z3 already uses common sub-expressions.
The example highlights some opportunities for simplification, noteworthy at(..) = "".
The example is solved in both versions after adding this simplification.
- AC completion which is exposed as an option to the new congruence closure core used roots of E-Graph which gets ordering of monomials out of sync.
- Added injective function handling to AC completion
- Move to model where all equations, also unit to unit are in completion
- throw in first level bound bodies into the E-graph to enable canonization on them.
* Initial plan
* Implement batch initialization fix for O(n²) datatype performance issue
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
* Fix the real O(n²) bottleneck with lazy hash table for constructor name lookups
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
* Optimize get_constructor_by_name: use func_decl* parameter, add linear search optimization for small datatypes, and ensure non-null postcondition
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
This allows using z3 for limited E-saturation simplification.
The tactic rewrites all assertions using the E-graph induced by the equalities and instantiated equality axioms.
It does allow solving with conditionals, although this is a first inefficient cut.
The following is a sample use case that rewrites to false.
```
(declare-fun prime () Int)
(declare-fun add (Int Int) Int)
(declare-fun mul (Int Int) Int)
(declare-fun ^ (Int Int) Int)
(declare-fun sub (Int Int) Int)
(declare-fun i () Int)
(declare-fun j () Int)
(declare-fun base () Int)
(declare-fun S () (Seq Int))
(declare-fun hash ((Seq Int) Int Int Int Int) Int)
(assert (let ((a!1 (mul (seq.nth S i) (^ base (sub (sub j i) 1)))))
(let ((a!2 (mod (add (hash S base prime (add i 1) j) a!1) prime)))
(not (= (hash S base prime i j) a!2)))))
(assert (forall ((x Int))
(! (= (mod (mod x prime) prime) (mod x prime))
:pattern ((mod (mod x prime) prime)))))
(assert (forall ((x Int) (y Int))
(! (= (mod (mul x y) prime) (mod (mul (mod x prime) y) prime))
:pattern ((mod (mul x y) prime))
:pattern ((mod (mul (mod x prime) y) prime)))))
(assert (forall ((x Int) (y Int))
(! (= (mod (mul x y) prime) (mod (mul x (mod y prime)) prime))
:pattern ((mod (mul x y) prime))
:pattern ((mod (mul x (mod y prime)) prime)))))
(assert (forall ((x Int) (y Int))
(! (= (mod (add x y) prime) (mod (add x (mod y prime)) prime))
:pattern ((mod (add x y) prime))
:pattern ((mod (add x (mod y prime)) prime)))))
(assert (forall ((x Int) (y Int))
(! (= (mod (add x y) prime) (mod (add (mod x prime) y) prime))
:pattern ((mod (add x y) prime))
:pattern ((mod (add (mod x prime) y) prime)))))
(assert (forall ((x Int) (y Int))
(! (= (mul x (^ x y)) (^ x (add y 1))) :pattern ((mul x (^ x y))))))
(assert (forall ((x Int) (y Int)) (! (= (mul x y) (mul y x)) :pattern ((mul x y)))))
(assert (forall ((x Int) (y Int)) (! (= (add x y) (add y x)) :pattern ((add x y)))))
(assert (forall ((x Int) (y Int)) (! (= (mul x y) (mul y x)) :pattern ((mul x y)))))
(assert (forall ((x Int) (y Int) (z Int))
(! (= (add x (add y z)) (add (add x y) z))
:pattern ((add x (add y z)))
:pattern ((add (add x y) z)))))
(assert (forall ((x Int) (y Int) (z Int))
(! (= (mul x (mul y z)) (mul (mul x y) z))
:pattern ((mul x (mul y z)))
:pattern ((mul (mul x y) z)))))
(assert (forall ((x Int) (y Int) (z Int))
(! (= (sub (sub x y) z) (sub (sub x z) y)) :pattern ((sub (sub x y) z)))))
(assert (forall ((x Int) (y Int) (z Int))
(! (= (mul x (add y z)) (add (mul x y) (mul x z)))
:pattern ((mul x (add y z))))))
(assert (forall ((x Int)) (! (= (sub (add x 1) 1) x) :pattern ((add x 1)))))
(assert (forall ((x Int)) (! (= (add (sub x 1) 1) x) :pattern ((sub x 1)))))
(assert (let ((a!1 (^ base (sub (sub (sub j 1) i) 1))))
(let ((a!2 (mod (add (hash S base prime (add i 1) (sub j 1))
(mul (seq.nth S i) a!1))
prime)))
(= (hash S base prime i (sub j 1)) a!2))))
(assert (let ((a!1 (add (seq.nth S (- j 1)) (mul base (hash S base prime i (sub j 1))))))
(= (hash S base prime i j) (mod a!1 prime))))
(assert (let ((a!1 (add (seq.nth S (- j 1))
(mul base (hash S base prime (add i 1) (sub j 1))))))
(= (hash S base prime (add i 1) j) (mod a!1 prime))))
(apply euf-completion)
```
To use conditional rewriting you can
```
(assert (not (= 0 prime)))
```
and update axioms using modulus with prime to be of the form:
```
(=> (not (= 0 prime)) <original-body of quantifier>)
```
* Introduce X-macro-based trace tag definition
- Created trace_tags.def to centralize TRACE tag definitions
- Each tag includes a symbolic name and description
- Set up enum class TraceTag for type-safe usage in TRACE macros
* Add script to generate Markdown documentation from trace_tags.def
- Python script parses trace_tags.def and outputs trace_tags.md
* Refactor TRACE_NEW to prepend TraceTag and pass enum to is_trace_enabled
* trace: improve trace tag handling system with hierarchical tagging
- Introduce hierarchical tag-class structure: enabling a tag class activates all child tags
- Unify TRACE, STRACE, SCTRACE, and CTRACE under enum TraceTag
- Implement initial version of trace_tag.def using X(tag, tag_class, description)
(class names and descriptions to be refined in a future update)
* trace: replace all string-based TRACE tags with enum TraceTag
- Migrated all TRACE, STRACE, SCTRACE, and CTRACE macros to use enum TraceTag values instead of raw string literals
* trace : add cstring header
* trace : Add Markdown documentation generation from trace_tags.def via mk_api_doc.py
* trace : rename macro parameter 'class' to 'tag_class' and remove Unicode comment in trace_tags.h.
* trace : Add TODO comment for future implementation of tag_class activation
* trace : Disable code related to tag_class until implementation is ready (#7663).
