gbuoy/test/regalloc.spec.ts

import { expect } from "chai"

import { edgeConnects } from "../lib/data/graph"
import { Loc } from "../lib/ir/loc"
import { AbsInsn2, CopyInsn, UnaryInsn } from "../lib/ir/insn"
import { allocateRegisters, interference, liveness } from "../lib/regalloc"
import { R8 } from "../lib/sm83/cpu"
import { BasicBlock } from "../lib/ir/block"

describe("liveness", () => {
    it("computes liveness", () => {
        const x = [0, 1, 2].map(i => Loc.vari("x" + i))
        const y = [0, 1].map(i => Loc.vari("y" + i))
        const block = new BasicBlock([
            CopyInsn(x[0], 1),
            UnaryInsn(x[1], "add", x[0]),
            UnaryInsn(x[2], "add", x[1]),
            UnaryInsn(y[0], "add", x[0]),
            UnaryInsn(y[1], "add", y[0]),
        ])

        const info = liveness(block)
        /* expect(info[0]).to.deep.equal(new Set())
        expect(info[1]).to.deep.equal(new Set([x[0]]))
        expect(info[2]).to.deep.equal(new Set([x[0], x[1]]))
        expect(info[3]).to.deep.equal(new Set([x[0], x[1], x[2]]))
        expect(info[4]).to.deep.equal(new Set([y[0], x[2]])) */
    })
})

describe("interference", () => {
    it("computes interference", () => {
        const block: BasicBlock = new BasicBlock([
            CopyInsn(Loc.vari("a"), 7),
            CopyInsn(Loc.vari("b"), 3),
            CopyInsn(Loc.vari("x"), Loc.vari("a")),
        ])

        const info = liveness(block)
        const g = interference(block, info)

        expect(edgeConnects(g, "a", "b")).to.be.true
    })
})

describe("allocateRegisters", () => {
    it("allocates registers", () => {
        const block: BasicBlock = new BasicBlock([
            CopyInsn(Loc.vari("a"), 7),
            CopyInsn(Loc.vari("b"), 3),
            CopyInsn(Loc.vari("x"), Loc.vari("a")),
        ])

        const alloc = allocateRegisters(block, Object.values(R8))

        expect(alloc.a).to.equal("A")
        expect(alloc.b).to.equal("B")
        expect(alloc.x).to.equal("A")
    })
})