code-buffer-vixl.cc (3246B)
1 // Copyright 2017, VIXL authors 2 // 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 are met: 6 // 7 // * Redistributions of source code must retain the above copyright notice, 8 // this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above copyright notice, 10 // this list of conditions and the following disclaimer in the documentation 11 // and/or other materials provided with the distribution. 12 // * Neither the name of ARM Limited nor the names of its contributors may be 13 // used to endorse or promote products derived from this software without 14 // specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND 17 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 20 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27 #include "code-buffer-vixl.h" 28 #include "utils-vixl.h" 29 30 namespace vixl { 31 32 CodeBuffer::CodeBuffer() : buffer_(nullptr), cursor_(nullptr), dirty_(false), capacity_(0) 33 { 34 } 35 36 CodeBuffer::CodeBuffer(byte* buffer, size_t capacity) 37 : buffer_(reinterpret_cast<byte*>(buffer)), 38 cursor_(reinterpret_cast<byte*>(buffer)), 39 dirty_(false), 40 capacity_(capacity) { 41 VIXL_ASSERT(buffer_ != NULL); 42 } 43 44 45 CodeBuffer::~CodeBuffer() VIXL_NEGATIVE_TESTING_ALLOW_EXCEPTION { 46 VIXL_ASSERT(!IsDirty()); 47 } 48 49 50 void CodeBuffer::EmitString(const char* string) { 51 const auto len = strlen(string) + 1; 52 VIXL_ASSERT(HasSpaceFor(len)); 53 char* dst = reinterpret_cast<char*>(cursor_); 54 dirty_ = true; 55 memcpy(dst, string, len); 56 cursor_ = reinterpret_cast<byte*>(dst + len); 57 } 58 59 60 void CodeBuffer::EmitData(const void* data, size_t size) { 61 VIXL_ASSERT(HasSpaceFor(size)); 62 dirty_ = true; 63 memcpy(cursor_, data, size); 64 cursor_ = cursor_ + size; 65 } 66 67 68 void CodeBuffer::UpdateData(size_t offset, const void* data, size_t size) { 69 dirty_ = true; 70 byte* dst = buffer_ + offset; 71 VIXL_ASSERT(dst + size <= cursor_); 72 memcpy(dst, data, size); 73 } 74 75 76 void CodeBuffer::Align() { 77 byte* end = AlignUp(cursor_, 4); 78 const size_t padding_size = end - cursor_; 79 VIXL_ASSERT(padding_size <= 4); 80 EmitZeroedBytes(static_cast<int>(padding_size)); 81 } 82 83 void CodeBuffer::EmitZeroedBytes(int n) { 84 VIXL_ASSERT(HasSpaceFor(n)); 85 dirty_ = true; 86 memset(cursor_, 0, n); 87 cursor_ += n; 88 } 89 90 void CodeBuffer::Reset() { 91 cursor_ = buffer_; 92 SetClean(); 93 } 94 95 void CodeBuffer::Reset(byte* buffer, size_t capacity) { 96 buffer_ = buffer; 97 cursor_ = buffer; 98 capacity_ = capacity; 99 SetClean(); 100 } 101 102 } // namespace vixl