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// This attempts to test that we can do an 8-bit sign extend no matter what the
// source register. This test is arguably somewhat tied to the baseline
// compiler's register allocator, but is still appropriate for most simple
// register allocators. It works by filling an increasing number of registers
// with values so as eventually to force the source operand for extend8_s into a
// register that does not have a byte personality.
for ( let i=0; i < 8; i++) {
let txt =
`(module
(func (export "f") (param i32) (result i32)
${adds(i)}
(local.set 0 (i32.extend8_s (i32.add (local.get 0) (i32.const 1))))
${drops(i)}
(local.get 0)))`;
let ins = new WebAssembly.Instance(new WebAssembly.Module(wasmTextToBinary(txt)));
assertEq(ins.exports.f(254), -1);
}
function adds(n) {
let s = ""
for ( let i=0; i < n; i++ )
s += "(i32.add (local.get 0) (i32.const 1))\n";
return s;
}
function drops(n) {
let s = "";
for ( let i=0; i < n; i++ )
s += "drop\n";
return s;
}