Class RewriteSimplifier

• Defined in File analyzer.h

Class Documentation

class RewriteSimplifier

Rewrite-rule based simplifier.

Public Functions

PrimExpr operator()(const PrimExpr &expr)

Simplify an expression under the current premises.

Parameters:

expr – The expression to simplify.

Returns:

An equivalent expression under those premises.

CompareResult TryCompare(const PrimExpr &lhs, const PrimExpr &rhs)

Compare signed integer expressions using active premises and constant offsets.

Parameters:

• lhs – The left-hand side of the comparison.

• rhs – The right-hand side of the comparison.

Returns:

The directly known ordering, or kUnknown when it cannot be established.

ffi::ObjectRef GetStatsCounters() const

Read cumulative rewrite statistics.

Returns:

A snapshot of the current counters.

void ResetStatsCounters()

Clear cumulative rewrite counters without changing facts or the rewrite limit.

void SetMaximumRewriteSteps(int64_t maximum)

Set the maximum allowed cumulative number of successful rewrites.

By default, the simplifier may perform as many steps as are required. If a positive limit is set, then the simplifier will throw an exception when exceeding that number of rewrite steps. This allows tests to guard against performance regressions.

Note: To maintain accurate usage counters, Analyzer instances should be re-used wherever possible. For example, TIR transformations should declare a single Analyzer that is used throughout the pass. Internal helpers may borrow its AnalyzerObj*.

The limit applies to the cumulative counter, not separately to each query. ResetStatsCounters starts a new accounting interval.

Parameters:

maximum – Positive rewrite limit, or a nonpositive value for no limit.