Crate onnx_runtime_optimizer 

onnx-runtime-optimizer

Device-independent graph→graph optimization passes for the ORT 2.0 runtime (see docs/ORT2.md §18 “Optimization Passes”). This is the first Phase-2 crate: pure, safe Rust graph rewriting over onnx_runtime_ir — no CUDA, no ORT C library, no FFI.

What lives here

Concept	Type
Pass contract	OptimizationPass, PassContext, run_passes
Dead-code removal	DeadNodeElimination
Bounded constant folding	ConstantFolding
Operator fusion	OpFusion, FusionPattern, PatternMatch
Errors	OptimizerError, Result

Pipeline

default_passes returns only the device-independent passes implemented here, in pipeline order: ConstantFolding → DeadNodeElimination → OpFusion.

Deferred (Phase 2b / Phase 3)

The full pipeline in docs/ORT2.md §18.1 also lists passes that depend on crates or analyses not yet built. They are intentionally not implemented here and are listed in default_passes’s source in their eventual pipeline position: ShapeInference (the loader owns inference for now), AttentionFusionPass, LayoutPropagation, PlacementOptimizer, TransferInsertion, InPlaceDetection, MemoryPlanning, CudaGraphRegionDetection, and OverlapScheduling.

Structs

ConstantFolding

Folds constant-input nodes into initializers (bounded, integer/shape only).

DeadNodeElimination

Removes nodes that do not contribute to any graph output.

FusionPattern

A fusion rule: an op-type sequence rewritten to a single replacement op.

OpFusion

The op-fusion pass: applies each FusionPattern to fixpoint.

PassContext

Shared, read-only context threaded through every pass.

PatternMatch

A matched occurrence of a FusionPattern in a graph.#[derive(Clone, Debug)]

Enums

OptimizerError

Crate-level error for the optimization pipeline.

Constants

CONTRIB_DOMAIN

The private contrib domain under which the optimizer emits every fused op.

Traits

InitializerResolver

Resolves graph initializer descriptors to their backing bytes.

OptimizationPass

A single graph→graph rewrite (see docs/ORT2.md §18.1).

Functions

default_fusion_patterns

The default device-independent fusion patterns.

default_passes

The device-independent Phase-1 pass pipeline, in run order.

run_passes

Run passes over graph in order.

Type Aliases

Result

A convenience Result alias for optimizer operations.