//
/// <summary>
/// Fetch disassembly for a range of instructions. May return more instructions than asked for.
/// </summary>
/// <param name="address">Beginning address of an instruction to use as a starting point for disassembly.</param>
/// <param name="nInstructions">Number of instructions to disassemble. Negative values indicate disassembly backwards from "address".</param>
/// <returns></returns>
public async Task<IEnumerable<DisasmInstruction>> FetchInstructions(ulong address, int nInstructions)
{
IEnumerable<DisasmInstruction> ret = null;
lock (_disassemlyCache)
{
// check the cache
var kv = _disassemlyCache.FirstOrDefault((p) => p.Value.TryFetch(address, nInstructions, out ret));
if (kv.Value != null)
return ret;
}
ulong endAddress;
ulong startAddress;
if (nInstructions >= 0)
{
startAddress = address;
endAddress = startAddress + (ulong)(_process.MaxInstructionSize * nInstructions);
}
else
{
endAddress = address;
startAddress = endAddress - (uint)(_process.MaxInstructionSize * -nInstructions);
endAddress++; // make sure to fetch an instruction covering the original start address
}
DisasmInstruction[] instructions = await Disassemble(_process, startAddress, endAddress);
if (instructions != null && instructions.Length > 0 && nInstructions < 0)
{
instructions = await VerifyDisassembly(instructions, startAddress, address);
}
if (instructions != null && instructions.Length > 0)
{
DisassemblyBlock block = new DisassemblyBlock(instructions);
lock (_disassemlyCache)
{
// push to the cache
DeleteRangeFromCache(block); // removes any entry with the same key
if (_disassemlyCache.Count >= cacheSize)
{
ulong max = 0;
int toDelete = -1;
for (int i = 0; i < _disassemlyCache.Count; ++i)
{
var e = _disassemlyCache.ElementAt(i);
if (e.Value.Touch > max)
{
max = e.Value.Touch;
toDelete = i;
}
}
Debug.Assert(toDelete >= 0, "Failed to flush from the cache");
_disassemlyCache.RemoveAt(toDelete);
}
_disassemlyCache.Add(block.Address, block);
}
var kv = block.TryFetch(address, nInstructions, out ret);
}
return ret;
}
private void DeleteRangeFromCache(DisassemblyBlock block)
{
for (int i = 0; i < _disassemlyCache.Count; ++i)
{
DisassemblyBlock elem = _disassemlyCache.ElementAt(i).Value;
if (block.Contains(elem.Address, elem.Count))
{
_disassemlyCache.RemoveAt(i);
break;
}
}
}
//
/// <summary>
/// Fetch disassembly for a range of instructions. May return more instructions than asked for.
/// </summary>
/// <param name="address">Beginning address of an instruction to use as a starting point for disassembly.</param>
/// <param name="nInstructions">Number of instructions to disassemble. Negative values indicate disassembly backwards from "address".</param>
/// <returns></returns>
public async Task <IEnumerable <DisasmInstruction> > FetchInstructions(ulong address, int nInstructions)
{
IEnumerable <DisasmInstruction> ret = null;
lock (_disassemlyCache)
{
// check the cache
var kv = _disassemlyCache.FirstOrDefault((p) => p.Value.TryFetch(address, nInstructions, out ret));
if (kv.Value != null)
{
return(ret);
}
}
ulong endAddress;
ulong startAddress;
if (nInstructions >= 0)
{
startAddress = address;
endAddress = startAddress + (ulong)(_process.MaxInstructionSize * nInstructions);
}
else
{
endAddress = address;
startAddress = endAddress - (uint)(_process.MaxInstructionSize * -nInstructions);
endAddress++; // make sure to fetch an instruction covering the original start address
}
DisasmInstruction[] instructions = await Disassemble(_process, startAddress, endAddress);
if (instructions != null && instructions.Length > 0 && nInstructions < 0)
{
instructions = await VerifyDisassembly(instructions, startAddress, address);
}
if (instructions != null && instructions.Length > 0)
{
DisassemblyBlock block = new DisassemblyBlock(instructions);
lock (_disassemlyCache)
{
// push to the cache
DeleteRangeFromCache(block); // removes any entry with the same key
if (_disassemlyCache.Count >= cacheSize)
{
long max = 0;
int toDelete = -1;
for (int i = 0; i < _disassemlyCache.Count; ++i)
{
var e = _disassemlyCache.ElementAt(i);
if (e.Value.Touch > max)
{
max = e.Value.Touch;
toDelete = i;
}
}
Debug.Assert(toDelete >= 0, "Failed to flush from the cache");
_disassemlyCache.RemoveAt(toDelete);
}
_disassemlyCache.Add(block.Address, block);
}
var kv = block.TryFetch(address, nInstructions, out ret);
}
return(ret);
}
