fn identify_zero_expressions(
fn_cov_info: &FunctionCoverageInfo,
counters_seen: &DenseBitSet<CounterId>,
expressions_seen: &DenseBitSet<ExpressionId>,
) -> DenseBitSet<ExpressionId>
Expand description
Identify expressions that will always have a value of zero, and note their
IDs in a DenseBitSet
. Mappings that refer to a zero expression can instead
become mappings to a constant zero value.
This function mainly exists to preserve the simplifications that were already being performed by the Rust-side expression renumbering, so that the resulting coverage mappings don’t get worse.