21 lines
710 B
Rust
21 lines
710 B
Rust
use rustc_index::bit_set::BitSet;
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use rustc_middle::mir::{self, Local};
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/// The set of locals in a MIR body that do not have `StorageLive`/`StorageDead` annotations.
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///
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/// These locals have fixed storage for the duration of the body.
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pub fn always_storage_live_locals(body: &mir::Body<'_>) -> BitSet<Local> {
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let mut always_live_locals = BitSet::new_filled(body.local_decls.len());
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for block in body.basic_blocks() {
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for statement in &block.statements {
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use mir::StatementKind::{StorageDead, StorageLive};
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if let StorageLive(l) | StorageDead(l) = statement.kind {
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always_live_locals.remove(l);
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}
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}
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}
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always_live_locals
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}
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