Struct DebugScanner 

pub struct DebugScanner {
    pub mode: DebugMode,
    /* private fields */
}

Shared NaN/Inf debug epilogue for every backend run loop.

Centralizes the RLX_DEBUG_NANS policy so each backend adds only a few lines: build one with DebugScanner::from_env before the loop, gate on enabled, and hand each computed node’s output + operand slices to check. The env var is read once (constructing the scanner), never per-node.

RLX_DEBUG_NANS values: unset / 0 / empty ⇒ Off; abort ⇒ Abort; anything else truthy ⇒ Warn.

Fields

mode: DebugMode

Implementations

impl DebugScanner

pub fn with_mode(mode: DebugMode, backend: &'static str) -> Self

Construct with an explicit mode (bypassing the env), tagging messages with backend. Useful in tests and when a caller drives the mode.

pub fn from_env(backend: &'static str) -> Self

Build from RLX_DEBUG_NANS, tagging messages with backend.

pub fn enabled(&self) -> bool

True when scanning is active — gate the (possibly expensive) readback and gather on this so production pays nothing.

pub fn check_outputs(&self, graph: &Graph, outputs: &[Vec<f32>])

Scan a whole-graph run’s outputs — the universal fallback for backends that execute opaquely (MPSGraph, MLX, CoreML MIL, PJRT/HLO) and can’t hook per-op. Reports which graph output first went non-finite, with its provenance. outputs is zipped against graph.outputs positionally, as every backend returns them in that order. No-op when scanning is off.

For internal localization on those backends, run the identical graph on the CPU backend with RLX_DEBUG_NANS — provenance is backend-neutral.

pub fn check( &self, graph: &Graph, node: NodeId, output: &[f32], inputs: &[(NodeId, &[f32])], ) -> Option<NanReport>

Scan one node’s output; on the first bad value, print a localized diagnostic and (in Abort mode) panic. Returns the report so callers may also collect/stop. No-op when the output is clean or scanning is off.

Trait Implementations

impl Clone for DebugScanner

fn clone(&self) -> DebugScanner

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for DebugScanner

impl Debug for DebugScanner

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.