v8/test/mjsunit/compiler/diamond-followedby-branch.js
Jun Lim 6bead6bd00 [compiler]Use Phi in Branch if control flow is known
This CL try to use a phi as a branch condition if the control flow from the
branch is known from previous conditions. This change will open up more branch
folding opportunities for later pass.

Change-Id: I26316ab3a68c2d58d0df53691981288a996d4ba1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1674484
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63434}
2019-08-28 19:12:03 +00:00

23 lines
687 B
JavaScript

// Copyright 2019 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --allow-natives-syntax
// Check that the branch elimination replace the redundant branch condition with
// a phi node, and then the branch is folded in EffectControlLinearizationPhase.
function foo(cond, v1, v2) {
cond = cond | 0;
var a = cond == 1 ? v1 : v2;
if(cond == 1) {
%TurbofanStaticAssert(a == v1);
} else {
%TurbofanStaticAssert(a == v2);
}
}
%PrepareFunctionForOptimization(foo);
foo(1, 10, 20); foo(2, 30, 40);
%OptimizeFunctionOnNextCall(foo);
foo(1, 10, 20); foo(2, 30, 40);