import type { AbsInsn2 } from "./insn"
import type { Loc } from "./loc"

export class BasicBlock {
    insns: Array<AbsInsn2>
    labels: { [label: string]: number }

    constructor(insns: Array<AbsInsn2>) {
        this.insns = insns
        this.labels = this.insns
            .reduce((labels, insn, i) => {
                if (insn.type !== "label") {
                    return labels
                }

                return {
                    ...labels,
                    [insn.dest]: i,
                }
            }, {})
    }

    locs(): Set<Loc> {
        return new Set(
            this.insns.flatMap(insn => {
                const insnLocs = []

                if (insn.type === "copy" || insn.type === "unary") {
                    insnLocs.push(insn.dest)

                    if (typeof insn.source !== "number") {
                        insnLocs.push(insn.source)
                    }
                }

                return insnLocs
            })
        )
    }
}