1/*
2 * Copyright (C) 2015-2017 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#if ENABLE(B3_JIT)
29
30#include "B3GenericBlockInsertionSet.h"
31#include "B3Procedure.h"
32#include <wtf/Insertion.h>
33#include <wtf/Vector.h>
34
35namespace JSC { namespace B3 {
36
37class InsertionSet;
38
39typedef GenericBlockInsertionSet<BasicBlock>::BlockInsertion BlockInsertion;
40
41class BlockInsertionSet : public GenericBlockInsertionSet<BasicBlock> {
42public:
43 BlockInsertionSet(Procedure&);
44 ~BlockInsertionSet();
45
46 // A helper to split a block when forward iterating over it. It creates a new block to hold
47 // everything before the instruction at valueIndex. The current block is left with
48 // everything at and after valueIndex. If the optional InsertionSet is provided, it will get
49 // executed on the newly created block - this makes sense if you had previously inserted
50 // things into the original block, since the newly created block will be indexed identically
51 // to how this block was indexed for all values prior to valueIndex. After this runs, it sets
52 // valueIndex to zero. This allows you to use this method for things like:
53 //
54 // for (unsigned valueIndex = 0; valueIndex < block->size(); ++valueIndex) {
55 // Value* value = block->at(valueIndex);
56 // if (value->opcode() == Foo) {
57 // BasicBlock* predecessor =
58 // m_blockInsertionSet.splitForward(block, valueIndex, &m_insertionSet);
59 // ... // Now you can append to predecessor, insert new blocks before 'block', and
60 // ... // you can use m_insertionSet to insert more thing before 'value'.
61 // predecessor->updatePredecessorsAfter();
62 // }
63 // }
64 //
65 // Note how usually this idiom ends in a all to updatePredecessorsAftter(), which ensures
66 // that the predecessors involved in any of the new control flow that you've created are up
67 // to date.
68 BasicBlock* splitForward(
69 BasicBlock*, unsigned& valueIndex, InsertionSet* = nullptr,
70 double frequency = PNaN);
71
72private:
73 Procedure& m_proc;
74};
75
76} } // namespace JSC::B3
77
78#endif // ENABLE(B3_JIT)
79