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// Point-testing various optimizations in the wasm baseline compiler.
// Boolean optimization for control (bug 1286816).
//
// These optimizations combine a test (a comparison or Eqz) with an
// immediately following conditional branch (BrIf, If, and Select), to
// avoid generating a boolean value that is then tested with a
// compare-to-zero.
//
// On AngryBots as of November 2016, 84% of all test instructions
// (measured statically) are optimized by this method.
function testEqzBrIf(value, type, untaken, taken, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(local i32)
(local.set 0 (${type}.const ${value}))
(local.set 1 (i32.const ${taken}))
(block $b
(br_if $b (${type}.eqz (local.get 0)))
(local.set 1 (i32.const ${untaken})))
(local.get 1))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64"].forEach(t => testEqzBrIf(0, t, 37, 42, 42)); // Taken
["i32", "i64"].forEach(t => testEqzBrIf(1, t, 37, 42, 37)); // Untaken
function testCmpBrIf(value, type, untaken, taken, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(local i32)
(local.set 1 (i32.const ${taken}))
(block $b
(br_if $b (${type}.eq (local.get 0) (${type}.const ${value})))
(local.set 1 (i32.const ${untaken})))
(local.get 1))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64", "f32", "f64"].forEach(t => testCmpBrIf(0, t, 37, 42, 42)); // Branch taken
["i32", "i64", "f32", "f64"].forEach(t => testCmpBrIf(1, t, 37, 42, 37)); // Branch untaken
function testEqzSelect(value, type, iftrue, iffalse, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(local.set 0 (${type}.const ${value}))
(select (i32.const ${iftrue})
(i32.const ${iffalse})
(${type}.eqz (local.get 0))))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64"].forEach(t => testEqzSelect(0, t, 42, 37, 42)); // Select first
["i32", "i64"].forEach(t => testEqzSelect(1, t, 42, 37, 37)); // Select second
function testCmpSelect(value, type, iftrue, iffalse, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(select (i32.const ${iftrue})
(i32.const ${iffalse})
(${type}.eq (local.get 0) (${type}.const ${value}))))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64", "f32", "f64"].forEach(t => testCmpSelect(0, t, 42, 37, 42)); // Select first
["i32", "i64", "f32", "f64"].forEach(t => testCmpSelect(1, t, 42, 37, 37)); // Select second
function testEqzIf(value, type, trueBranch, falseBranch, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(local i32)
(local.set 0 (${type}.const ${value}))
(if (${type}.eqz (local.get 0))
(then (local.set 1 (i32.const ${trueBranch})))
(else (local.set 1 (i32.const ${falseBranch}))))
(local.get 1))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64"].forEach(t => testEqzIf(0, t, 42, 37, 42)); // Taken
["i32", "i64"].forEach(t => testEqzIf(1, t, 42, 37, 37)); // Untaken
function testCmpIf(value, type, trueBranch, falseBranch, expected) {
var f = wasmEvalText(`(module
(func (result i32)
(local ${type})
(local i32)
(if (${type}.eq (local.get 0) (${type}.const ${value}))
(then (local.set 1 (i32.const ${trueBranch})))
(else (local.set 1 (i32.const ${falseBranch}))))
(local.get 1))
(export "f" (func 0)))`).exports["f"];
assertEq(f(), expected);
}
["i32", "i64", "f32", "f64"].forEach(t => testCmpIf(0, t, 42, 37, 42)); // Taken
["i32", "i64", "f32", "f64"].forEach(t => testCmpIf(1, t, 42, 37, 37)); // Untaken
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