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
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
/*
* Copyright (C) 2017-2019 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.
*/
#include "config.h"
#include "AirStackAllocation.h"
#if ENABLE(B3_JIT)
#include "AirCode.h"
#include "StackAlignment.h"
#include <wtf/ListDump.h>
namespace JSC { namespace B3 { namespace Air {
namespace {
namespace AirStackAllocationInternal {
static constexpr bool verbose = false;
}
template<typename Collection>
void updateFrameSizeBasedOnStackSlotsImpl(Code& code, const Collection& collection)
{
unsigned frameSize = 0;
for (StackSlot* slot : collection)
frameSize = std::max(frameSize, static_cast<unsigned>(-slot->offsetFromFP()));
code.setFrameSize(WTF::roundUpToMultipleOf<stackAlignmentBytes()>(frameSize) + stackAdjustmentForAlignment());
}
} // anonymous namespace
bool attemptAssignment(
StackSlot* slot, intptr_t offsetFromFP, const Vector<StackSlot*>& otherSlots)
{
if (AirStackAllocationInternal::verbose)
dataLog("Attempting to assign ", pointerDump(slot), " to ", offsetFromFP, " with interference ", pointerListDump(otherSlots), "\n");
// Need to align it to the slot's desired alignment.
offsetFromFP = -WTF::roundUpToMultipleOf(slot->alignment(), -offsetFromFP);
for (StackSlot* otherSlot : otherSlots) {
if (!otherSlot->offsetFromFP())
continue;
bool overlap = WTF::rangesOverlap(
offsetFromFP,
offsetFromFP + static_cast<intptr_t>(slot->byteSize()),
otherSlot->offsetFromFP(),
otherSlot->offsetFromFP() + static_cast<intptr_t>(otherSlot->byteSize()));
if (overlap)
return false;
}
if (AirStackAllocationInternal::verbose)
dataLog("Assigned ", pointerDump(slot), " to ", offsetFromFP, "\n");
slot->setOffsetFromFP(offsetFromFP);
return true;
}
void assign(StackSlot* slot, const Vector<StackSlot*>& otherSlots)
{
if (AirStackAllocationInternal::verbose)
dataLog("Attempting to assign ", pointerDump(slot), " with interference ", pointerListDump(otherSlots), "\n");
if (attemptAssignment(slot, -static_cast<intptr_t>(slot->byteSize()), otherSlots))
return;
for (StackSlot* otherSlot : otherSlots) {
if (!otherSlot->offsetFromFP())
continue;
bool didAssign = attemptAssignment(
slot, otherSlot->offsetFromFP() - static_cast<intptr_t>(slot->byteSize()), otherSlots);
if (didAssign)
return;
}
RELEASE_ASSERT_NOT_REACHED();
}
Vector<StackSlot*> allocateAndGetEscapedStackSlotsWithoutChangingFrameSize(Code& code)
{
// Allocate all of the escaped slots in order. This is kind of a crazy algorithm to allow for
// the possibility of stack slots being assigned frame offsets before we even get here.
RELEASE_ASSERT(code.frameSize() == stackAdjustmentForAlignment());
Vector<StackSlot*> assignedEscapedStackSlots;
Vector<StackSlot*> escapedStackSlotsWorklist;
for (StackSlot* slot : code.stackSlots()) {
if (slot->isLocked()) {
if (slot->offsetFromFP())
assignedEscapedStackSlots.append(slot);
else
escapedStackSlotsWorklist.append(slot);
} else {
// It would be super strange to have an unlocked stack slot that has an offset already.
ASSERT(!slot->offsetFromFP());
}
}
// This is a fairly expensive loop, but it's OK because we'll usually only have a handful of
// escaped stack slots.
while (!escapedStackSlotsWorklist.isEmpty()) {
StackSlot* slot = escapedStackSlotsWorklist.takeLast();
assign(slot, assignedEscapedStackSlots);
assignedEscapedStackSlots.append(slot);
}
return assignedEscapedStackSlots;
}
void allocateEscapedStackSlots(Code& code)
{
updateFrameSizeBasedOnStackSlotsImpl(
code, allocateAndGetEscapedStackSlotsWithoutChangingFrameSize(code));
}
void updateFrameSizeBasedOnStackSlots(Code& code)
{
updateFrameSizeBasedOnStackSlotsImpl(code, code.stackSlots());
}
} } } // namespace JSC::B3::Air
#endif // ENABLE(B3_JIT)
|
