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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Routines used by both the compiler and the expression compiler.
*/
#pragma once
#include <libsolidity/codegen/CompilerContext.h>
#include <libsolidity/ast/ASTForward.h>
namespace dev {
namespace solidity {
class Type; // forward
class CompilerUtils
{
public:
CompilerUtils(CompilerContext& _context): m_context(_context) {}
/// Stores the initial value of the free-memory-pointer at its position;
void initialiseFreeMemoryPointer();
/// Copies the free memory pointer to the stack.
void fetchFreeMemoryPointer();
/// Stores the free memory pointer from the stack.
void storeFreeMemoryPointer();
/// Allocates a number of bytes in memory as given on the stack.
/// Stack pre: <size>
/// Stack post: <mem_start>
void allocateMemory();
/// Appends code that transforms memptr to (memptr - free_memptr) memptr
void toSizeAfterFreeMemoryPointer();
/// Loads data from memory to the stack.
/// @param _offset offset in memory (or calldata)
/// @param _type data type to load
/// @param _fromCalldata if true, load from calldata, not from memory
/// @param _padToWords if true, assume the data is padded to full words (32 bytes)
/// @returns the number of bytes consumed in memory.
unsigned loadFromMemory(
unsigned _offset,
Type const& _type = IntegerType(256),
bool _fromCalldata = false,
bool _padToWords = false
);
/// Dynamic version of @see loadFromMemory, expects the memory offset on the stack.
/// Stack pre: memory_offset
/// Stack post: value... (memory_offset+length)
void loadFromMemoryDynamic(
Type const& _type,
bool _fromCalldata = false,
bool _padToWords = true,
bool _keepUpdatedMemoryOffset = true
);
/// Stores a 256 bit integer from stack in memory.
/// @param _offset offset in memory
/// @param _type type of the data on the stack
void storeInMemory(unsigned _offset);
/// Dynamic version of @see storeInMemory, expects the memory offset below the value on the stack
/// and also updates that. For reference types, only copies the data pointer. Fails for
/// non-memory-references.
/// @param _padToWords if true, adds zeros to pad to multiple of 32 bytes. Array elements
/// are always padded (except for byte arrays), regardless of this parameter.
/// Stack pre: memory_offset value...
/// Stack post: (memory_offset+length)
void storeInMemoryDynamic(Type const& _type, bool _padToWords = true);
/// Copies values (of types @a _givenTypes) given on the stack to a location in memory given
/// at the stack top, encoding them according to the ABI as the given types @a _targetTypes.
/// Removes the values from the stack and leaves the updated memory pointer.
/// Stack pre: <v1> <v2> ... <vn> <memptr>
/// Stack post: <memptr_updated>
/// Does not touch the memory-free pointer.
/// @param _padToWords if false, all values are concatenated without padding.
/// @param _copyDynamicDataInPlace if true, dynamic types is stored (without length)
/// together with fixed-length data.
/// @param _encodeAsLibraryTypes if true, encodes for a library function, e.g. does not
/// convert storage pointer types to memory types.
/// @note the locations of target reference types are ignored, because it will always be
/// memory.
void encodeToMemory(
TypePointers const& _givenTypes = {},
TypePointers const& _targetTypes = {},
bool _padToWords = true,
bool _copyDynamicDataInPlace = false,
bool _encodeAsLibraryTypes = false
);
/// Zero-initialises (the data part of) an already allocated memory array.
/// Length has to be nonzero!
/// Stack pre: <length> <memptr>
/// Stack post: <updated_memptr>
void zeroInitialiseMemoryArray(ArrayType const& _type);
/// Copies full 32 byte words in memory (regions cannot overlap), i.e. may copy more than length.
/// Stack pre: <size> <target> <source>
/// Stack post:
void memoryCopy32();
/// Copies data in memory (regions cannot overlap).
/// Stack pre: <size> <target> <source>
/// Stack post:
void memoryCopy();
/// Converts the combined and left-aligned (right-aligned if @a _rightAligned is true)
/// external function type <address><function identifier> into two stack slots:
/// address (right aligned), function identifier (right aligned)
void splitExternalFunctionType(bool _rightAligned);
/// Performs the opposite operation of splitExternalFunctionType(_rightAligned)
void combineExternalFunctionType(bool _rightAligned);
/// Appends code that combines the construction-time (if available) and runtime function
/// entry label of the given function into a single stack slot.
/// Note: This might cause the compilation queue of the runtime context to be extended.
void pushCombinedFunctionEntryLabel(Declaration const& _function);
/// Appends code for an implicit or explicit type conversion. This includes erasing higher
/// order bits (@see appendHighBitCleanup) when widening integer but also copy to memory
/// if a reference type is converted from calldata or storage to memory.
/// If @a _cleanupNeeded, high order bits cleanup is also done if no type conversion would be
/// necessary.
/// If @a _chopSignBits, the function resets the signed bits out of the width of the signed integer.
void convertType(Type const& _typeOnStack, Type const& _targetType, bool _cleanupNeeded = false, bool _chopSignBits = false);
/// Creates a zero-value for the given type and puts it onto the stack. This might allocate
/// memory for memory references.
void pushZeroValue(Type const& _type);
/// Moves the value that is at the top of the stack to a stack variable.
void moveToStackVariable(VariableDeclaration const& _variable);
/// Copies an item that occupies @a _itemSize stack slots from a stack depth of @a _stackDepth
/// to the top of the stack.
void copyToStackTop(unsigned _stackDepth, unsigned _itemSize);
/// Moves an item that occupies @a _itemSize stack slots and has items occupying @a _stackDepth
/// slots above it to the top of the stack.
void moveToStackTop(unsigned _stackDepth, unsigned _itemSize = 1);
/// Moves @a _itemSize elements past @a _stackDepth other stack elements
void moveIntoStack(unsigned _stackDepth, unsigned _itemSize = 1);
/// Rotates the topmost @a _items items on the stack, such that the previously topmost element
/// is bottom-most.
void rotateStackUp(unsigned _items);
/// Rotates the topmost @a _items items on the stack, such that the previously bottom-most element
/// is now topmost.
void rotateStackDown(unsigned _items);
/// Removes the current value from the top of the stack.
void popStackElement(Type const& _type);
/// Removes element from the top of the stack _amount times.
void popStackSlots(size_t _amount);
template <class T>
static unsigned sizeOnStack(std::vector<T> const& _variables);
static unsigned sizeOnStack(std::vector<std::shared_ptr<Type const>> const& _variableTypes);
/// Appends code that computes tha SHA3 hash of the topmost stack element of 32 byte type.
void computeHashStatic();
/// Bytes we need to the start of call data.
/// - The size in bytes of the function (hash) identifier.
static const unsigned dataStartOffset;
/// Position of the free-memory-pointer in memory;
static const size_t freeMemoryPointer;
private:
/// Address of the precompiled identity contract.
static const unsigned identityContractAddress;
/// Stores the given string in memory.
/// Stack pre: mempos
/// Stack post:
void storeStringData(bytesConstRef _data);
/// Appends code that cleans higher-order bits for integer types.
void cleanHigherOrderBits(IntegerType const& _typeOnStack);
/// Prepares the given type for storing in memory by shifting it if necessary.
unsigned prepareMemoryStore(Type const& _type, bool _padToWords);
/// Loads type from memory assuming memory offset is on stack top.
unsigned loadFromMemoryHelper(Type const& _type, bool _fromCalldata, bool _padToWords);
CompilerContext& m_context;
};
template <class T>
unsigned CompilerUtils::sizeOnStack(std::vector<T> const& _variables)
{
unsigned size = 0;
for (T const& variable: _variables)
size += variable->annotation().type->sizeOnStack();
return size;
}
}
}
|
