public void OutpReplaceSimple()
{
var m = new ProcedureBuilder();
var block = m.Label("block");
var foo = new Identifier("foo", PrimitiveType.Word32, null);
var pfoo = new Identifier("pfoo", PrimitiveType.Pointer32, null);
m.Assign(foo, 3);
var sid = new SsaIdentifier(foo, foo, m.Block.Statements.Last, null, false);
var ssaIds = new SsaIdentifierCollection { { foo, sid } };
var opt = new OutParameterTransformer(null, ssaIds);
opt.ReplaceDefinitionsWithOutParameter(foo, pfoo);
Assert.AreEqual("*pfoo = 0x00000003", m.Block.Statements[0].ToString());
}
private void PerformTest(FileUnitTester fut)
{
DataFlowAnalysis dfa = new DataFlowAnalysis(program, new FakeDecompilerEventListener());
dfa.UntangleProcedures();
foreach (Procedure proc in program.Procedures.Values)
{
Aliases alias = new Aliases(proc, program.Architecture);
alias.Transform();
SsaTransform sst = new SsaTransform(dfa.ProgramDataFlow, proc, proc.CreateBlockDominatorGraph());
SsaState ssa = sst.SsaState;
proc.Write(false, fut.TextWriter);
fut.TextWriter.WriteLine();
OutParameterTransformer opt = new OutParameterTransformer(proc, ssa.Identifiers);
opt.Transform();
DeadCode.Eliminate(proc, ssa);
proc.Write(false, fut.TextWriter);
fut.TextWriter.WriteLine("====================");
}
}
/// <summary>
/// Processes procedures individually, building complex expression trees out
/// of the simple, close-to-the-machine code generated by the disassembly.
/// </summary>
/// <param name="rl"></param>
public void BuildExpressionTrees()
{
int i = 0;
foreach (Procedure proc in program.Procedures.Values)
{
eventListener.ShowProgress("Building complex expressions.", i, program.Procedures.Values.Count);
++i;
try
{
var larw = new LongAddRewriter(proc, program.Architecture);
larw.Transform();
Aliases alias = new Aliases(proc, program.Architecture, flow);
alias.Transform();
var doms = new DominatorGraph<Block>(proc.ControlGraph, proc.EntryBlock);
var sst = new SsaTransform(flow, proc, doms);
var ssa = sst.SsaState;
var cce = new ConditionCodeEliminator(ssa.Identifiers, program.Platform);
cce.Transform();
DeadCode.Eliminate(proc, ssa);
var vp = new ValuePropagator(ssa.Identifiers, proc);
vp.Transform();
DeadCode.Eliminate(proc, ssa);
// Build expressions. A definition with a single use can be subsumed
// into the using expression.
var coa = new Coalescer(proc, ssa);
coa.Transform();
DeadCode.Eliminate(proc, ssa);
var liv = new LinearInductionVariableFinder(
proc,
ssa.Identifiers,
new BlockDominatorGraph(proc.ControlGraph, proc.EntryBlock));
liv.Find();
foreach (KeyValuePair<LinearInductionVariable, LinearInductionVariableContext> de in liv.Contexts)
{
var str = new StrengthReduction(ssa, de.Key, de.Value);
str.ClassifyUses();
str.ModifyUses();
}
var opt = new OutParameterTransformer(proc, ssa.Identifiers);
opt.Transform();
DeadCode.Eliminate(proc, ssa);
// Definitions with multiple uses and variables joined by PHI functions become webs.
var web = new WebBuilder(proc, ssa.Identifiers, program.InductionVariables);
web.Transform();
ssa.ConvertBack(false);
}
catch (Exception ex)
{
eventListener.Error(new NullCodeLocation(proc.Name), ex, "An error occurred during data flow analysis.");
}
}
}
public void OutpReplacePhi()
{
var m = new ProcedureBuilder();
var foo = new Identifier("foo", PrimitiveType.Word32, null);
var foo1 = new Identifier("foo1", PrimitiveType.Word32, null);
var foo2 = new Identifier("foo2", PrimitiveType.Word32, null);
var foo3 = new Identifier("foo3", PrimitiveType.Word32, null);
var pfoo = new Identifier("pfoo", PrimitiveType.Pointer32, null);
Block block1 = m.Label("block1");
m.Assign(foo1, Constant.Word32(1));
Statement stmFoo1 = m.Block.Statements.Last;
Block block2 = m.Label("block2");
m.Assign(foo2, Constant.Word32(2));
Statement stmFoo2 = m.Block.Statements.Last;
Block block3 = m.Label("block3");
Statement stmFoo3 = m.Phi(foo3, foo1, foo2);
SsaIdentifierCollection ssaIds = new SsaIdentifierCollection();
ssaIds.Add(foo1, new SsaIdentifier(foo1, foo, stmFoo1, null, false));
ssaIds.Add(foo2, new SsaIdentifier(foo2, foo, stmFoo2, null, false));
ssaIds.Add(foo3, new SsaIdentifier(foo3, foo, stmFoo3, null, false));
OutParameterTransformer opt = new OutParameterTransformer(null, ssaIds);
opt.ReplaceDefinitionsWithOutParameter(foo3, pfoo);
Assert.AreEqual("*pfoo = 0x00000001", stmFoo1.Instruction.ToString());
Assert.AreEqual("*pfoo = 0x00000002", stmFoo2.Instruction.ToString());
Assert.AreEqual("foo3 = PHI(foo1, foo2)", stmFoo3.Instruction.ToString());
}
public void OutpReplaceManyUses()
{
ProcedureBuilder m = new ProcedureBuilder();
Identifier foo = new Identifier("foo", PrimitiveType.Word32, null);
Identifier bar = new Identifier("bar", PrimitiveType.Word32, null);
Identifier pfoo = new Identifier("pfoo", PrimitiveType.Pointer32, null);
Block block = m.Label("block");
m.Assign(foo, 1);
Statement stmFoo = m.Block.Statements.Last;
m.Assign(bar, foo);
Statement stmBar = m.Block.Statements.Last;
SsaIdentifier ssaFoo = new SsaIdentifier(foo, foo, stmFoo, ((Assignment) stmFoo.Instruction).Src, false);
ssaFoo.Uses.Add(stmBar);
SsaIdentifier ssaBar = new SsaIdentifier(bar, bar, stmBar, ((Assignment) stmBar.Instruction).Src, false);
SsaIdentifierCollection ssaIds = new SsaIdentifierCollection();
ssaIds.Add(foo, ssaFoo);
ssaIds.Add(bar, ssaBar);
OutParameterTransformer opt = new OutParameterTransformer(m.Procedure, ssaIds);
opt.ReplaceDefinitionsWithOutParameter(foo, pfoo);
Assert.AreEqual(3, block.Statements.Count);
Assert.AreEqual("foo = 0x00000001", block.Statements[0].Instruction.ToString());
Assert.AreEqual("*pfoo = foo", block.Statements[1].Instruction.ToString());
Assert.AreEqual("bar = foo", block.Statements[2].Instruction.ToString());
}
