unroll6.js - mozsearch

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// |jit-test| test-also=--setpref=wasm_unroll_loops=true

// Loop unrolling test: 0 exiting values, 2 exit targets => can be unrolled.

// This is a modified version of unroll2.js.

let t = `

(module

  (memory (export "mem") 1)

  (func (export "not_really_memset")

        (param $start i32) (param $byte i32) (param $count i32)

    (local $limit i32)

    (local.set $limit (i32.add (local.get $start) (local.get $count)))

    (loop $cont

      (if (i32.lt_u (local.get $start) (local.get $limit)) (then

        (i32.store8 (local.get $start)

                    (i32.xor (local.get $byte) (i32.const 0)))

        (local.set $start (i32.add (local.get $start) (i32.const 1)))

        (if (i32.lt_u (local.get $start) (local.get $limit)) (then

          (i32.store8 (local.get $start)

                      (i32.add (local.get $byte) (i32.const 100)))

          (local.set $start (i32.add (local.get $start) (i32.const 1)))

          ;; continue

          (br $cont)

))

        ;; implied else-clause exits the loop

))

      ;; implied else-clause exits the loop

)`;

let i = //wasmEvalText(t);

    new WebAssembly.Instance(new WebAssembly.Module(wasmTextToBinary(t)));

i.exports.not_really_memset(1, 22, 1);

i.exports.not_really_memset(3, 33, 2);

i.exports.not_really_memset(6, 44, 3);

i.exports.not_really_memset(10, 55, 4);

i.exports.not_really_memset(15, 66, 5);

i.exports.not_really_memset(21, 77, 6);

i.exports.not_really_memset(28, 88, 7);

i.exports.not_really_memset(36, 99, 8);

let buf = new Uint8Array(i.exports.mem.buffer);

let s = "";

for (let i = 0; i < 45; i++) {

    s = s + (buf[i] + " ");

// The last number (22, 133, 44, 155, etc) in each zero-bordered group is of

// the form XX if the loop terminates via its first exit edge, and 1XX if it

// terminates by its second exit edge.

let expected =

    "0 22 0 33 133 0 44 144 44 0 55 155 55 155 0 66 166 66 166 66 0 77 177 " +

    "77 177 77 177 0 88 188 88 188 88 188 88 0 99 199 99 199 99 199 99 199 0 ";

assertEq(s, expected);