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// |jit-test| skip-if: !wasmSimdEnabled() || !hasDisassembler() || wasmCompileMode() != "baseline" || !getBuildConfiguration("arm64")
// Test that the vixl logic for v128 constant loads is at least somewhat
// reasonable.
var lead = `0x[0-9a-f]+ +[0-9a-f]{8} +`;
var prefix = `${lead}sub sp, sp, #0x.. \\(..\\)
${lead}str x23, \\[sp, #..\\]`;
var suffix =
`${lead}b #\\+0x8 \\(addr 0x.*\\)
${lead}brk #0xf000`;
for ( let [bits, expected, values] of [
// If high == low and the byte is 0 or ff then a single movi is sufficient.
['i8x16 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00', `
${prefix}
${lead}movi v0\\.2d, #0x0
${suffix}
`,
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]],
['i8x16 -1 0 -1 0 -1 0 -1 0 -1 0 -1 0 -1 0 -1 0', `
${prefix}
${lead}movi v0\\.2d, #0xff00ff00ff00ff
${suffix}
`,
[-1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0]],
// Splattable small things (up to a byte, at a byte location)
// can also use just one instruction
['i32x4 1 1 1 1', `
${prefix}
${lead}movi v0\\.4s, #0x1, lsl #0
${suffix}
`,
[1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0]],
['i32x4 0x300 0x300 0x300 0x300', `
${prefix}
${lead}movi v0\\.4s, #0x3, lsl #8
${suffix}
`,
[0, 3, 0, 0, 0, 3, 0, 0, 0, 3, 0, 0, 0, 3, 0, 0]],
// If high == low but the value is more complex then a constant load
// plus a dup is sufficient. x16 is the designated temp.
['i32x4 1 2 1 2', `
${prefix}
${lead}mov x16, #0x1
${lead}movk x16, #0x2, lsl #32
${lead}dup v0\\.2d, x16
${suffix}
`,
[1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0]],
// If high != low then we degenerate to a more complicated pattern: dup the low value
// and then overwrite the high part with the high value.
['i32x4 1 2 2 1', `
${prefix}
${lead}mov x16, #0x1
${lead}movk x16, #0x2, lsl #32
${lead}dup v0\\.2d, x16
${lead}mov x16, #0x2
${lead}movk x16, #0x1, lsl #32
${lead}mov v0\\.d\\[1\\], x16
${suffix}
`,
[1, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0]],
// Things are not always bleak, and vixl finds a way.
['i32x4 1 1 2 2', `
${prefix}
${lead}movi v0\\.4s, #0x1, lsl #0
${lead}mov x16, #0x200000002
${lead}mov v0\\.d\\[1\\], x16
${suffix}
`,
[1, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0]],
] ) {
let ins = wasmEvalText(`
(module
(memory (export "mem") 1)
(func (export "run")
(v128.store (i32.const 0) (call $f)))
(func $f (export "f") (result v128)
(v128.const ${bits})))`);
let output = wasmDis(ins.exports.f, {tier:"baseline", asString:true});
assertEq(output.match(new RegExp(expected)) != null, true);
let mem = new Int8Array(ins.exports.mem.buffer);
set(mem, 0, iota(16).map(x => -1-x));
ins.exports.run();
assertSame(get(mem, 0, 16), values);
}
function get(arr, loc, len) {
let res = [];
for ( let i=0; i < len; i++ ) {
res.push(arr[loc+i]);
}
return res;
}
function set(arr, loc, vals) {
for ( let i=0; i < vals.length; i++ ) {
arr[loc+i] = vals[i];
}
}