1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
/*
* Copyright (C) 2014 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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.
*/
#ifndef DFGPhantomCanonicalizationPhase_h
#define DFGPhantomCanonicalizationPhase_h
#if ENABLE(DFG_JIT)
namespace JSC { namespace DFG {
class Graph;
// Replaces all pre-existing Phantoms with Checks or removes them if the Check is unnecessary. If
// the Phantom was necessary (it uses a node that is relevant to OSR) then the Phantom is hoisted
// to just below the node.
//
// This phase is only valid in SSA, because it's only in SSA that Phantoms are ignored for the
// purpose of liveness-at-some-point and are only used for absolute liveness.
//
// This phase makes a lot of things easier, like CFG simplification: you don't have to insert any
// phantoms when jettisoning a CFG edge.
bool performPhantomCanonicalization(Graph&);
} } // namespace JSC::DFG
#endif // ENABLE(DFG_JIT)
#endif // DFGPhantomCanonicalizationPhase_h
|
