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// Copyright 2013 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Flags: --allow-natives-syntax
var X = 1.1;
var K = 0.5;
var O = 0;
var result = new Float64Array(2);
%NeverOptimizeFunction(spill);
function spill() {
}
function buggy() {
var v = X;
var phi1 = v + K;
var phi2 = v - K;
spill(); // At this point initial values for phi1 and phi2 are spilled.
var xmm1 = v;
var xmm2 = v*v*v;
var xmm3 = v*v*v*v;
var xmm4 = v*v*v*v*v;
var xmm5 = v*v*v*v*v*v;
var xmm6 = v*v*v*v*v*v*v;
var xmm7 = v*v*v*v*v*v*v*v;
var xmm8 = v*v*v*v*v*v*v*v*v;
// All registers are blocked and phis for phi1 and phi2 are spilled because
// their left (incoming) value is spilled, there are no free registers,
// and phis themselves have only ANY-policy uses.
for (var x = 0; x < 2; x++) {
xmm1 += xmm1 * xmm6;
xmm2 += xmm1 * xmm5;
xmm3 += xmm1 * xmm4;
xmm4 += xmm1 * xmm3;
xmm5 += xmm1 * xmm2;
// Now swap values of phi1 and phi2 to create cycle between phis.
var t = phi1;
phi1 = phi2;
phi2 = t;
}
// Now we want to get values of phi1 and phi2. However we would like to
// do it in a way that does not produce any uses of phi1&phi2 that have
// a register beneficial policy. How? We just hide these uses behind phis.
result[0] = (O === 0) ? phi1 : phi2;
result[1] = (O !== 0) ? phi1 : phi2;
}
function test() {
buggy();
assertArrayEquals([X + K, X - K], result);
}
test();
test();
%OptimizeFunctionOnNextCall(buggy);
test();
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