Function insert_phis_all

crates/rustc_codegen_spirv/src/linker/mem2reg.rs:159–206

Returns true if variables were rewritten

(
    header: &mut ModuleHeader,
    types_global_values: &mut Vec<Instruction>,
    pointer_to_pointee: &FxHashMap<Word, Word>,
    constants: &FxHashMap<Word, u32>,
    blocks: &mut [Block],
    dom

// Returns true if variables were rewritten
fn insert_phis_all(
    header: &mut ModuleHeader,
    types_global_values: &mut Vec<Instruction>,
    pointer_to_pointee: &FxHashMap<Word, Word>,
    constants: &FxHashMap<Word, u32>,
    blocks: &mut [Block],
    dominance_frontier: &[FxHashSet<usize>],
) -> bool {
    let var_maps_and_types = blocks[0]
        .instructions
        .iter()
        .filter(|inst| inst.class.opcode == Op::Variable)
        .filter_map(|inst| {
            let var = inst.result_id.unwrap();
            let var_ty = *pointer_to_pointee.get(&inst.result_type.unwrap()).unwrap();
            Some((
                collect_access_chains(pointer_to_pointee, constants, blocks, var, var_ty)?,
                var_ty,
            ))
        })
        .collect::<Vec<_>>();
    if var_maps_and_types.is_empty() {
        return false;
    }
    for (var_map, _) in &var_maps_and_types {
        split_copy_memory(header, blocks, var_map);
    }
    for &(ref var_map, base_var_type) in &var_maps_and_types {
        let blocks_with_phi = insert_phis(blocks, dominance_frontier, var_map);
        let mut renamer = Renamer {
            header,
            types_global_values,
            blocks,
            blocks_with_phi,
            base_var_type,
            var_map,
            phi_defs: FxHashSet::default(),
            visited: FxHashSet::default(),
            stack: Vec::new(),
            rewrite_rules: FxHashMap::default(),
        };
        renamer.rename(0, None);
        apply_rewrite_rules(&renamer.rewrite_rules, blocks);
        remove_nops(blocks);
    }
    remove_old_variables(blocks, &var_maps_and_types);
    true
}

#[derive(Debug)]
struct VarInfo {