public bool ProcessIndirectControlTransfer(Address addrSwitch, RtlTransfer xfer)
{
List <Address> vector;
ImageMapVectorTable imgVector;
Expression swExp;
UserIndirectJump indJump;
var listener = scanner.Services.RequireService <DecompilerEventListener>();
if (program.User.IndirectJumps.TryGetValue(addrSwitch, out indJump))
{
vector = indJump.Table.Addresses;
swExp = this.frame.EnsureIdentifier(indJump.IndexRegister);
imgVector = indJump.Table;
}
else
{
var bw = new Backwalker <Block, Instruction>(new BackwalkerHost(this), xfer, eval);
if (!bw.CanBackwalk())
{
return(false);
}
var bwops = bw.BackWalk(blockCur);
if (bwops == null || bwops.Count == 0)
{
return(false); //$REVIEW: warn?
}
Identifier idIndex = bw.Index != null
? blockCur.Procedure.Frame.EnsureRegister(bw.Index)
: null;
VectorBuilder builder = new VectorBuilder(scanner.Services, program, new DirectedGraphImpl <object>());
if (bw.VectorAddress == null)
{
return(false);
}
vector = builder.BuildAux(bw, addrSwitch, state);
if (vector.Count == 0)
{
var rdr = program.CreateImageReader(bw.VectorAddress);
if (!rdr.IsValid)
{
return(false);
}
// Can't determine the size of the table, but surely it has one entry?
var addrEntry = arch.ReadCodeAddress(bw.Stride, rdr, state);
string msg;
if (this.program.SegmentMap.IsValidAddress(addrEntry))
{
vector.Add(addrEntry);
msg = "Can't determine size of jump vector; probing only one entry.";
}
else
{
// Nope, not even that.
msg = "No valid entries could be found in jump vector.";
}
var nav = listener.CreateJumpTableNavigator(program, addrSwitch, bw.VectorAddress, bw.Stride);
listener.Warn(nav, msg);
if (vector.Count == 0)
{
return(false);
}
}
imgVector = new ImageMapVectorTable(
bw.VectorAddress,
vector.ToArray(),
builder.TableByteSize);
swExp = idIndex;
if (idIndex == null || idIndex.Name == "None")
{
swExp = bw.IndexExpression;
}
}
ScanVectorTargets(xfer, vector);
if (xfer is RtlGoto)
{
var blockSource = scanner.FindContainingBlock(ric.Address);
blockCur = blockSource;
foreach (Address addr in vector)
{
var dest = scanner.FindContainingBlock(addr);
Debug.Assert(dest != null, "The block at address " + addr + "should have been enqueued.");
blockSource.Procedure.ControlGraph.AddEdge(blockSource, dest);
}
if (swExp == null)
{
scanner.Warn(addrSwitch, "Unable to determine index variable for indirect jump.");
Emit(new ReturnInstruction());
blockSource.Procedure.ControlGraph.AddEdge(
blockSource,
blockSource.Procedure.ExitBlock);
}
else
{
Emit(new SwitchInstruction(swExp, blockCur.Procedure.ControlGraph.Successors(blockCur).ToArray()));
}
}
if (imgVector.Size > 0)
{
program.ImageMap.AddItemWithSize(imgVector.Address, imgVector);
}
else
{
program.ImageMap.AddItem(imgVector.Address, imgVector);
}
return(true);
}
public bool ProcessIndirectControlTransfer(Address addrSwitch, RtlTransfer xfer)
{
var bw = new Backwalker(new BackwalkerHost(this), xfer, eval);
if (!bw.CanBackwalk())
{
return(false);
}
var bwops = bw.BackWalk(blockCur);
if (bwops == null || bwops.Count == 0)
{
return(false); //$REVIEW: warn?
}
var idIndex = blockCur.Procedure.Frame.EnsureRegister(bw.Index);
VectorBuilder builder = new VectorBuilder(scanner, program, new DirectedGraphImpl <object>());
if (bw.VectorAddress == null)
{
return(false);
}
List <Address> vector = builder.BuildAux(bw, addrSwitch, state);
if (vector.Count == 0)
{
var addrNext = bw.VectorAddress + bw.Stride;
var rdr = scanner.CreateReader(bw.VectorAddress);
if (!rdr.IsValid)
{
return(false);
}
// Can't determine the size of the table, but surely it has one entry?
var addrEntry = arch.ReadCodeAddress(bw.Stride, rdr, state);
if (this.program.Image.IsValidAddress(addrEntry))
{
vector.Add(addrEntry);
scanner.Warn(addrSwitch, "Can't determine size of jump vector; probing only one entry.");
}
else
{
// Nope, not even that.
scanner.Warn(addrSwitch, "No valid entries could be found in jump vector.");
}
}
//$TODO: mark the vector
ScanVectorTargets(xfer, vector);
if (xfer is RtlGoto)
{
var blockSource = scanner.FindContainingBlock(ric.Address);
blockCur = blockSource;
foreach (Address addr in vector)
{
var dest = scanner.FindContainingBlock(addr);
Debug.Assert(dest != null, "The block at address " + addr + "should have been enqueued.");
blockSource.Procedure.ControlGraph.AddEdge(blockSource, dest);
}
Expression swExp = idIndex;
if (idIndex.Name == "None")
{
swExp = bw.IndexExpression;
}
if (swExp == null)
{
throw new NotImplementedException();
}
Emit(new SwitchInstruction(swExp, blockCur.Procedure.ControlGraph.Successors(blockCur).ToArray()));
}
//vectorUses[wi.addrFrom] = new VectorUse(wi.Address, builder.IndexRegister);
program.ImageMap.AddItem(bw.VectorAddress,
new ImageMapVectorTable(xfer is RtlCall, vector.ToArray(), builder.TableByteSize));
return(true);
}