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" 11245431Sdim#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) { 24245431Sdim assert(LastChar >= FirstChar && "Invalid start/end range"); 25234285Sdim } 26234285Sdim 27245431Sdim virtual uint64_t getBase() const LLVM_OVERRIDE { return 0; } 28245431Sdim virtual uint64_t getExtent() const LLVM_OVERRIDE { 29245431Sdim return LastChar - FirstChar; 30245431Sdim } 31245431Sdim virtual int readByte(uint64_t address, uint8_t* ptr) const LLVM_OVERRIDE; 32234285Sdim virtual int readBytes(uint64_t address, 33234285Sdim uint64_t size, 34263509Sdim uint8_t *buf) const LLVM_OVERRIDE; 35245431Sdim virtual const uint8_t *getPointer(uint64_t address, 36245431Sdim uint64_t size) const LLVM_OVERRIDE; 37245431Sdim virtual bool isValidAddress(uint64_t address) const LLVM_OVERRIDE { 38234285Sdim return validAddress(address); 39234285Sdim } 40245431Sdim virtual bool isObjectEnd(uint64_t address) const LLVM_OVERRIDE { 41245431Sdim return objectEnd(address); 42245431Sdim } 43234285Sdim 44234285Sdimprivate: 45234285Sdim const uint8_t* const FirstChar; 46234285Sdim const uint8_t* const LastChar; 47234285Sdim 48234285Sdim // These are implemented as inline functions here to avoid multiple virtual 49234285Sdim // calls per public function 50234285Sdim bool validAddress(uint64_t address) const { 51234285Sdim return static_cast<ptrdiff_t>(address) < LastChar - FirstChar; 52234285Sdim } 53234285Sdim bool objectEnd(uint64_t address) const { 54234285Sdim return static_cast<ptrdiff_t>(address) == LastChar - FirstChar; 55234285Sdim } 56234285Sdim 57245431Sdim RawMemoryObject(const RawMemoryObject&) LLVM_DELETED_FUNCTION; 58245431Sdim void operator=(const RawMemoryObject&) LLVM_DELETED_FUNCTION; 59234285Sdim}; 60234285Sdim 61234285Sdimint RawMemoryObject::readByte(uint64_t address, uint8_t* ptr) const { 62234285Sdim if (!validAddress(address)) return -1; 63234285Sdim *ptr = *((uint8_t *)(uintptr_t)(address + FirstChar)); 64234285Sdim return 0; 65234285Sdim} 66234285Sdim 67234285Sdimint RawMemoryObject::readBytes(uint64_t address, 68234285Sdim uint64_t size, 69263509Sdim uint8_t *buf) const { 70234285Sdim if (!validAddress(address) || !validAddress(address + size - 1)) return -1; 71234285Sdim memcpy(buf, (uint8_t *)(uintptr_t)(address + FirstChar), size); 72234285Sdim return size; 73234285Sdim} 74234285Sdim 75234285Sdimconst uint8_t *RawMemoryObject::getPointer(uint64_t address, 76234285Sdim uint64_t size) const { 77234285Sdim return FirstChar + address; 78234285Sdim} 79234285Sdim} // anonymous namespace 80234285Sdim 81234285Sdimnamespace llvm { 82234285Sdim// If the bitcode has a header, then its size is known, and we don't have to 83234285Sdim// block until we actually want to read it. 84234285Sdimbool StreamingMemoryObject::isValidAddress(uint64_t address) const { 85234285Sdim if (ObjectSize && address < ObjectSize) return true; 86234285Sdim return fetchToPos(address); 87234285Sdim} 88234285Sdim 89234285Sdimbool StreamingMemoryObject::isObjectEnd(uint64_t address) const { 90234285Sdim if (ObjectSize) return address == ObjectSize; 91234285Sdim fetchToPos(address); 92234285Sdim return address == ObjectSize && address != 0; 93234285Sdim} 94234285Sdim 95234285Sdimuint64_t StreamingMemoryObject::getExtent() const { 96234285Sdim if (ObjectSize) return ObjectSize; 97234285Sdim size_t pos = BytesRead + kChunkSize; 98234285Sdim // keep fetching until we run out of bytes 99234285Sdim while (fetchToPos(pos)) pos += kChunkSize; 100234285Sdim return ObjectSize; 101234285Sdim} 102234285Sdim 103234285Sdimint StreamingMemoryObject::readByte(uint64_t address, uint8_t* ptr) const { 104234285Sdim if (!fetchToPos(address)) return -1; 105234285Sdim *ptr = Bytes[address + BytesSkipped]; 106234285Sdim return 0; 107234285Sdim} 108234285Sdim 109234285Sdimint StreamingMemoryObject::readBytes(uint64_t address, 110234285Sdim uint64_t size, 111263509Sdim uint8_t *buf) const { 112234285Sdim if (!fetchToPos(address + size - 1)) return -1; 113234285Sdim memcpy(buf, &Bytes[address + BytesSkipped], size); 114234285Sdim return 0; 115234285Sdim} 116234285Sdim 117234285Sdimbool StreamingMemoryObject::dropLeadingBytes(size_t s) { 118234285Sdim if (BytesRead < s) return true; 119234285Sdim BytesSkipped = s; 120234285Sdim BytesRead -= s; 121234285Sdim return false; 122234285Sdim} 123234285Sdim 124234285Sdimvoid StreamingMemoryObject::setKnownObjectSize(size_t size) { 125234285Sdim ObjectSize = size; 126234285Sdim Bytes.reserve(size); 127234285Sdim} 128234285Sdim 129234285SdimStreamableMemoryObject *getNonStreamedMemoryObject( 130234285Sdim const unsigned char *Start, const unsigned char *End) { 131234285Sdim return new RawMemoryObject(Start, End); 132234285Sdim} 133234285Sdim 134234285SdimStreamableMemoryObject::~StreamableMemoryObject() { } 135234285Sdim 136234285SdimStreamingMemoryObject::StreamingMemoryObject(DataStreamer *streamer) : 137234285Sdim Bytes(kChunkSize), Streamer(streamer), BytesRead(0), BytesSkipped(0), 138234285Sdim ObjectSize(0), EOFReached(false) { 139234285Sdim BytesRead = streamer->GetBytes(&Bytes[0], kChunkSize); 140234285Sdim} 141234285Sdim} 142