description( "This tests that register allocation still works under register pressure induced by inlining, out-of-line function calls (i.e. unconditional register flushing), and slow paths for object creation (i.e. conditional register flushing)." ); // Inlineable constructor. function foo(a, b, c) { this.a = a; this.b = b; this.c = c; } // Non-inlineable function. This relies on a size limit for inlining, but still // produces integers. It also relies on the VM not reasoning about Math.log deeply // enough to find some way of optimizing this code to be small enough to inline. function bar(a, b) { a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; a += b; a -= b; b ^= a; a += Math.log(b); b += a; b -= a; a ^= b; return (a - b) | 0; } // Function into which we will inline foo but not bar. function baz(a, b) { return new foo(bar(2 * a + 1, b - 1), bar(2 * a, b - 1), a); } // Do the test. It's crucial that o.a, o.b, and o.c are checked on each // loop iteration. for (var i = 0; i < 1000; ++i) { var o = baz(i, i + 1); shouldBe("o.a", "bar(2 * i + 1, i)"); shouldBe("o.b", "bar(2 * i, i)"); shouldBe("o.c", "i"); }