1 /*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "assembler.h"
18
19 #include <algorithm>
20 #include <vector>
21
22 #ifdef ART_ENABLE_CODEGEN_arm
23 #include "arm/assembler_thumb2.h"
24 #endif
25 #ifdef ART_ENABLE_CODEGEN_arm64
26 #include "arm64/assembler_arm64.h"
27 #endif
28 #ifdef ART_ENABLE_CODEGEN_mips
29 #include "mips/assembler_mips.h"
30 #endif
31 #ifdef ART_ENABLE_CODEGEN_mips64
32 #include "mips64/assembler_mips64.h"
33 #endif
34 #ifdef ART_ENABLE_CODEGEN_x86
35 #include "x86/assembler_x86.h"
36 #endif
37 #ifdef ART_ENABLE_CODEGEN_x86_64
38 #include "x86_64/assembler_x86_64.h"
39 #endif
40 #include "base/casts.h"
41 #include "globals.h"
42 #include "memory_region.h"
43
44 namespace art {
45
AssemblerBuffer(ArenaAllocator * arena)46 AssemblerBuffer::AssemblerBuffer(ArenaAllocator* arena)
47 : arena_(arena) {
48 static const size_t kInitialBufferCapacity = 4 * KB;
49 contents_ = arena_->AllocArray<uint8_t>(kInitialBufferCapacity, kArenaAllocAssembler);
50 cursor_ = contents_;
51 limit_ = ComputeLimit(contents_, kInitialBufferCapacity);
52 fixup_ = nullptr;
53 slow_path_ = nullptr;
54 #ifndef NDEBUG
55 has_ensured_capacity_ = false;
56 fixups_processed_ = false;
57 #endif
58
59 // Verify internal state.
60 CHECK_EQ(Capacity(), kInitialBufferCapacity);
61 CHECK_EQ(Size(), 0U);
62 }
63
64
~AssemblerBuffer()65 AssemblerBuffer::~AssemblerBuffer() {
66 if (arena_->IsRunningOnMemoryTool()) {
67 arena_->MakeInaccessible(contents_, Capacity());
68 }
69 }
70
71
ProcessFixups(const MemoryRegion & region)72 void AssemblerBuffer::ProcessFixups(const MemoryRegion& region) {
73 AssemblerFixup* fixup = fixup_;
74 while (fixup != nullptr) {
75 fixup->Process(region, fixup->position());
76 fixup = fixup->previous();
77 }
78 }
79
80
FinalizeInstructions(const MemoryRegion & instructions)81 void AssemblerBuffer::FinalizeInstructions(const MemoryRegion& instructions) {
82 // Copy the instructions from the buffer.
83 MemoryRegion from(reinterpret_cast<void*>(contents()), Size());
84 instructions.CopyFrom(0, from);
85 // Process fixups in the instructions.
86 ProcessFixups(instructions);
87 #ifndef NDEBUG
88 fixups_processed_ = true;
89 #endif
90 }
91
92
ExtendCapacity(size_t min_capacity)93 void AssemblerBuffer::ExtendCapacity(size_t min_capacity) {
94 size_t old_size = Size();
95 size_t old_capacity = Capacity();
96 DCHECK_GT(min_capacity, old_capacity);
97 size_t new_capacity = std::min(old_capacity * 2, old_capacity + 1 * MB);
98 new_capacity = std::max(new_capacity, min_capacity);
99
100 // Allocate the new data area and copy contents of the old one to it.
101 contents_ = reinterpret_cast<uint8_t*>(
102 arena_->Realloc(contents_, old_capacity, new_capacity, kArenaAllocAssembler));
103
104 // Update the cursor and recompute the limit.
105 cursor_ = contents_ + old_size;
106 limit_ = ComputeLimit(contents_, new_capacity);
107
108 // Verify internal state.
109 CHECK_EQ(Capacity(), new_capacity);
110 CHECK_EQ(Size(), old_size);
111 }
112
ImplicitlyAdvancePC()113 void DebugFrameOpCodeWriterForAssembler::ImplicitlyAdvancePC() {
114 uint32_t pc = dchecked_integral_cast<uint32_t>(assembler_->CodeSize());
115 if (delay_emitting_advance_pc_) {
116 uint32_t stream_pos = dchecked_integral_cast<uint32_t>(opcodes_.size());
117 delayed_advance_pcs_.push_back(DelayedAdvancePC {stream_pos, pc});
118 } else {
119 AdvancePC(pc);
120 }
121 }
122
123 } // namespace art
124