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// |jit-test| skip-if: wasmCompileMode() != "ion"
// Tests that unrolling actually transforms a loop into something new, by
// unrolling a loop with just one FP mul and one FP add in it and checking that
// the resulting assembly contains 4 FP muls and 4 FP adds. Matching bits of
// text in the disassembly is necessarily platform-dependent, but we don't care
// about that since unrolling is done at the MIR level, so if it works for one
// target, it works for all.
//
// Test inspired by simd/pmaddubsw-x64-ion-codegen.js.
const isX64 = getBuildConfiguration("x64") && !getBuildConfiguration("simulator");
if (hasDisassembler() && isX64) {
let t = `
(module
(memory 1)
(func (export "dot_product")
(param $startA i32) (param $startB i32) (param $count i32)
(local $sum f64)
(if (i32.gt_u (local.get $count) (i32.const 0))
(then
(loop $cont
(local.set $sum (f64.add (local.get $sum)
(f64.mul (f64.load (local.get $startA))
(f64.load (local.get $startB)))))
(local.set $startA (i32.add (local.get $startA) (i32.const 8)))
(local.set $startB (i32.add (local.get $startB) (i32.const 8)))
(local.set $count (i32.sub (local.get $count) (i32.const 1)))
(br_if $cont (i32.gt_u (local.get $count) (i32.const 0)))
)
)
)
)
)`;
let i = new WebAssembly.Instance(
new WebAssembly.Module(wasmTextToBinary(t)));
const output = wasmDis(i.exports.dot_product, {tier:"ion", asString:true})
.replace(/^[0-9a-f]{8} (?:[0-9a-f]{2} )+\n?\s+/gmi, "");
// Find four "mulsd .. addsd" bits of text. One pair for the peeled
// iteration and 3 pairs for the 3 unrolled iterations.
const re = /\bv?mulsd[^\n]+\nv?addsd /g;
assertEq(re.exec(output) != null, true);
assertEq(re.exec(output) != null, true);
assertEq(re.exec(output) != null, true);
assertEq(re.exec(output) != null, true);
assertEq(re.exec(output) == null, true);
}