1 /**
2 * Copyright (c) 2021-2022 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #ifndef LIBPANDAFILE_BYTECODE_INSTRUCTION_INL_H_
17 #define LIBPANDAFILE_BYTECODE_INSTRUCTION_INL_H_
18
19 #include "bytecode_instruction.h"
20 #include "macros.h"
21
22 namespace panda {
23
24 template <const BytecodeInstMode Mode>
25 template <class R, class S>
ReadHelper(size_t byteoffset,size_t bytecount,size_t offset,size_t width)26 inline auto BytecodeInst<Mode>::ReadHelper(size_t byteoffset, size_t bytecount, size_t offset, size_t width) const
27 {
28 constexpr size_t BYTE_WIDTH = 8;
29
30 size_t right_shift = offset % BYTE_WIDTH;
31
32 S v = 0;
33 for (size_t i = 0; i < bytecount; i++) {
34 S mask = static_cast<S>(ReadByte(byteoffset + i)) << (i * BYTE_WIDTH);
35 v |= mask;
36 }
37
38 v >>= right_shift;
39 size_t left_shift = sizeof(R) * BYTE_WIDTH - width;
40
41 // Do sign extension using arithmetic shift. It's implementation defined
42 // so we check such behavior using static assert
43 // NOLINTNEXTLINE(hicpp-signed-bitwise)
44 static_assert((-1 >> 1) == -1);
45
46 // NOLINTNEXTLINE(hicpp-signed-bitwise)
47 return static_cast<R>(v << left_shift) >> left_shift;
48 }
49
50 template <const BytecodeInstMode Mode>
51 template <size_t offset, size_t width, bool is_signed /* = false */>
Read()52 inline auto BytecodeInst<Mode>::Read() const
53 {
54 constexpr size_t BYTE_WIDTH = 8;
55 constexpr size_t BYTE_OFFSET = offset / BYTE_WIDTH;
56 constexpr size_t BYTE_OFFSET_END = (offset + width + BYTE_WIDTH - 1) / BYTE_WIDTH;
57 constexpr size_t BYTE_COUNT = BYTE_OFFSET_END - BYTE_OFFSET;
58
59 using storage_type = helpers::TypeHelperT<BYTE_COUNT * BYTE_WIDTH, false>;
60 using return_type = helpers::TypeHelperT<width, is_signed>;
61
62 return ReadHelper<return_type, storage_type>(BYTE_OFFSET, BYTE_COUNT, offset, width);
63 }
64
65 template <const BytecodeInstMode Mode>
66 template <bool is_signed /* = false */>
Read64(size_t offset,size_t width)67 inline auto BytecodeInst<Mode>::Read64(size_t offset, size_t width) const
68 {
69 constexpr size_t BIT64 = 64;
70 constexpr size_t BYTE_WIDTH = 8;
71
72 ASSERT((offset % BYTE_WIDTH) + width <= BIT64);
73
74 size_t byteoffset = offset / BYTE_WIDTH;
75 size_t byteoffset_end = (offset + width + BYTE_WIDTH - 1) / BYTE_WIDTH;
76 size_t bytecount = byteoffset_end - byteoffset;
77
78 using storage_type = helpers::TypeHelperT<BIT64, false>;
79 using return_type = helpers::TypeHelperT<BIT64, is_signed>;
80
81 return ReadHelper<return_type, storage_type>(byteoffset, bytecount, offset, width);
82 }
83
84 template <const BytecodeInstMode Mode>
GetSize()85 inline size_t BytecodeInst<Mode>::GetSize() const
86 {
87 return Size(GetFormat());
88 }
89
90 #include <bytecode_instruction-inl_gen.h>
91
92 } // namespace panda
93
94 #endif // LIBPANDAFILE_BYTECODE_INSTRUCTION_INL_H_
95