1234285Sdim//===- StreamableMemoryObject.cpp - Streamable data interface -------------===// 2234285Sdim// 3234285Sdim// The LLVM Compiler Infrastructure 4234285Sdim// 5234285Sdim// This file is distributed under the University of Illinois Open Source 6234285Sdim// License. See LICENSE.TXT for details. 7234285Sdim// 8234285Sdim//===----------------------------------------------------------------------===// 9234285Sdim 10234285Sdim#include "llvm/Support/StreamableMemoryObject.h" 11243830Sdim#include "llvm/Support/Compiler.h" 12234285Sdim#include <cassert> 13234285Sdim#include <cstring> 14234285Sdim 15234285Sdim 16234285Sdimusing namespace llvm; 17234285Sdim 18234285Sdimnamespace { 19234285Sdim 20234285Sdimclass RawMemoryObject : public StreamableMemoryObject { 21234285Sdimpublic: 22234285Sdim RawMemoryObject(const unsigned char *Start, const unsigned char *End) : 23234285Sdim FirstChar(Start), LastChar(End) { 24239462Sdim assert(LastChar >= FirstChar && "Invalid start/end range"); 25234285Sdim } 26234285Sdim 27243830Sdim virtual uint64_t getBase() const LLVM_OVERRIDE { return 0; } 28243830Sdim virtual uint64_t getExtent() const LLVM_OVERRIDE { 29243830Sdim return LastChar - FirstChar; 30243830Sdim } 31243830Sdim virtual int readByte(uint64_t address, uint8_t* ptr) const LLVM_OVERRIDE; 32234285Sdim virtual int readBytes(uint64_t address, 33234285Sdim uint64_t size, 34234285Sdim uint8_t* buf, 35243830Sdim uint64_t* copied) const LLVM_OVERRIDE; 36243830Sdim virtual const uint8_t *getPointer(uint64_t address, 37243830Sdim uint64_t size) const LLVM_OVERRIDE; 38243830Sdim virtual bool isValidAddress(uint64_t address) const LLVM_OVERRIDE { 39234285Sdim return validAddress(address); 40234285Sdim } 41243830Sdim virtual bool isObjectEnd(uint64_t address) const LLVM_OVERRIDE { 42243830Sdim return objectEnd(address); 43243830Sdim } 44234285Sdim 45234285Sdimprivate: 46234285Sdim const uint8_t* const FirstChar; 47234285Sdim const uint8_t* const LastChar; 48234285Sdim 49234285Sdim // These are implemented as inline functions here to avoid multiple virtual 50234285Sdim // calls per public function 51234285Sdim bool validAddress(uint64_t address) const { 52234285Sdim return static_cast<ptrdiff_t>(address) < LastChar - FirstChar; 53234285Sdim } 54234285Sdim bool objectEnd(uint64_t address) const { 55234285Sdim return static_cast<ptrdiff_t>(address) == LastChar - FirstChar; 56234285Sdim } 57234285Sdim 58243830Sdim RawMemoryObject(const RawMemoryObject&) LLVM_DELETED_FUNCTION; 59243830Sdim void operator=(const RawMemoryObject&) LLVM_DELETED_FUNCTION; 60234285Sdim}; 61234285Sdim 62234285Sdimint RawMemoryObject::readByte(uint64_t address, uint8_t* ptr) const { 63234285Sdim if (!validAddress(address)) return -1; 64234285Sdim *ptr = *((uint8_t *)(uintptr_t)(address + FirstChar)); 65234285Sdim return 0; 66234285Sdim} 67234285Sdim 68234285Sdimint RawMemoryObject::readBytes(uint64_t address, 69234285Sdim uint64_t size, 70234285Sdim uint8_t* buf, 71234285Sdim uint64_t* copied) const { 72234285Sdim if (!validAddress(address) || !validAddress(address + size - 1)) return -1; 73234285Sdim memcpy(buf, (uint8_t *)(uintptr_t)(address + FirstChar), size); 74234285Sdim if (copied) *copied = size; 75234285Sdim return size; 76234285Sdim} 77234285Sdim 78234285Sdimconst uint8_t *RawMemoryObject::getPointer(uint64_t address, 79234285Sdim uint64_t size) const { 80234285Sdim return FirstChar + address; 81234285Sdim} 82234285Sdim} // anonymous namespace 83234285Sdim 84234285Sdimnamespace llvm { 85234285Sdim// If the bitcode has a header, then its size is known, and we don't have to 86234285Sdim// block until we actually want to read it. 87234285Sdimbool StreamingMemoryObject::isValidAddress(uint64_t address) const { 88234285Sdim if (ObjectSize && address < ObjectSize) return true; 89234285Sdim return fetchToPos(address); 90234285Sdim} 91234285Sdim 92234285Sdimbool StreamingMemoryObject::isObjectEnd(uint64_t address) const { 93234285Sdim if (ObjectSize) return address == ObjectSize; 94234285Sdim fetchToPos(address); 95234285Sdim return address == ObjectSize && address != 0; 96234285Sdim} 97234285Sdim 98234285Sdimuint64_t StreamingMemoryObject::getExtent() const { 99234285Sdim if (ObjectSize) return ObjectSize; 100234285Sdim size_t pos = BytesRead + kChunkSize; 101234285Sdim // keep fetching until we run out of bytes 102234285Sdim while (fetchToPos(pos)) pos += kChunkSize; 103234285Sdim return ObjectSize; 104234285Sdim} 105234285Sdim 106234285Sdimint StreamingMemoryObject::readByte(uint64_t address, uint8_t* ptr) const { 107234285Sdim if (!fetchToPos(address)) return -1; 108234285Sdim *ptr = Bytes[address + BytesSkipped]; 109234285Sdim return 0; 110234285Sdim} 111234285Sdim 112234285Sdimint StreamingMemoryObject::readBytes(uint64_t address, 113234285Sdim uint64_t size, 114234285Sdim uint8_t* buf, 115234285Sdim uint64_t* copied) const { 116234285Sdim if (!fetchToPos(address + size - 1)) return -1; 117234285Sdim memcpy(buf, &Bytes[address + BytesSkipped], size); 118234285Sdim if (copied) *copied = size; 119234285Sdim return 0; 120234285Sdim} 121234285Sdim 122234285Sdimbool StreamingMemoryObject::dropLeadingBytes(size_t s) { 123234285Sdim if (BytesRead < s) return true; 124234285Sdim BytesSkipped = s; 125234285Sdim BytesRead -= s; 126234285Sdim return false; 127234285Sdim} 128234285Sdim 129234285Sdimvoid StreamingMemoryObject::setKnownObjectSize(size_t size) { 130234285Sdim ObjectSize = size; 131234285Sdim Bytes.reserve(size); 132234285Sdim} 133234285Sdim 134234285SdimStreamableMemoryObject *getNonStreamedMemoryObject( 135234285Sdim const unsigned char *Start, const unsigned char *End) { 136234285Sdim return new RawMemoryObject(Start, End); 137234285Sdim} 138234285Sdim 139234285SdimStreamableMemoryObject::~StreamableMemoryObject() { } 140234285Sdim 141234285SdimStreamingMemoryObject::StreamingMemoryObject(DataStreamer *streamer) : 142234285Sdim Bytes(kChunkSize), Streamer(streamer), BytesRead(0), BytesSkipped(0), 143234285Sdim ObjectSize(0), EOFReached(false) { 144234285Sdim BytesRead = streamer->GetBytes(&Bytes[0], kChunkSize); 145234285Sdim} 146234285Sdim} 147