public void BwInvertedCondition()
{
var ebx = m.Reg32("ebx", 3);
var eax = m.Reg32("eax", 0);
var CZ = m.Flags("CZ");
m.Assign(CZ, m.Cond(m.ISub(ebx, 0x30)));
m.BranchIf(m.Test(ConditionCode.ULE, CZ), "do_switch");
m.Goto("default_case");
m.Label("do_switch");
m.Assign(eax, 0);
var block = m.CurrentBlock;
var xfer = new RtlGoto(m.Mem32(m.IAdd(Constant.Word32(0x00123400), m.IMul(ebx, 4))), InstrClass.Transfer);
m.Label("default_case");
m.Return();
var bw = new Backwalker <Block, Instruction>(host, xfer, expSimp);
Assert.IsTrue(bw.CanBackwalk());
var ops = bw.BackWalk(block);
Assert.AreEqual(3, ops.Count);
Assert.AreEqual("cmp 48", ops[0].ToString());
Assert.AreEqual("branch UGT", ops[1].ToString());
Assert.AreEqual("* 4", ops[2].ToString());
}
public void CfgcJmpToBranch()
{
var m = new ProcedureBuilder();
var c = m.Temp(PrimitiveType.Bool, "c");
var pfn = m.Temp(PrimitiveType.Pointer32, "pfn");
m.Label("m1");
m.BranchIf(c, "m3");
m.Label("m2");
m.Goto("m3");
m.Label("m3");
m.SideEffect(m.Fn(pfn));
m.Return();
var sExp =
#region Expected
@"// ProcedureBuilder
// Return size: 0
void ProcedureBuilder()
ProcedureBuilder_entry:
pfn()
return
// succ: ProcedureBuilder_exit
m1:
m3:
ProcedureBuilder_exit:
";
#endregion
var cfgc = new ControlFlowGraphCleaner(m.Procedure);
cfgc.Transform();
var sw = new StringWriter();
m.Procedure.Write(false, sw);
Assert.AreEqual(sExp, sw.ToString());
}
public void TrfPropagateStackValuesToSuccessor()
{
m.Label("Start");
Identifier ecx = m.Register(1);
trf = CreateTrashedRegisterFinder(program);
CreateBlockFlow(m.Block, m.Frame);
trf.StartProcessingBlock(m.Block);
trf.StackSymbolicValues[-4] = ecx;
trf.StackSymbolicValues[-8] = ecx;
trf.StackSymbolicValues[-12] = ecx;
trf.StackSymbolicValues[-16] = m.Word32(0x1234);
trf.StackSymbolicValues[-20] = m.Word32(0x5678);
trf.StackSymbolicValues[-24] = m.Word32(0x9ABC);
var succ = new Block(m.Procedure, "succ");
var sf = CreateBlockFlow(succ, m.Frame);
flow[succ] = sf;
sf.SymbolicIn.StackState[-8] = ecx;
sf.SymbolicIn.StackState[-12] = Constant.Word32(1231);
sf.SymbolicIn.StackState[-20] = Constant.Word32(0x5678);
sf.SymbolicIn.StackState[-24] = Constant.Word32(0xCCCC);
trf.PropagateToSuccessorBlock(succ);
Assert.AreEqual("ecx", sf.SymbolicIn.StackState[-4].ToString(), "Didn't have a value before");
Assert.AreEqual("ecx", sf.SymbolicIn.StackState[-8].ToString(), "Same value as before");
Assert.AreEqual("<invalid>", sf.SymbolicIn.StackState[-12].ToString());
Assert.AreEqual("0x00001234", sf.SymbolicIn.StackState[-16].ToString());
Assert.AreEqual("0x00005678", sf.SymbolicIn.StackState[-20].ToString());
Assert.AreEqual("<invalid>", sf.SymbolicIn.StackState[-24].ToString());
}
/// <summary>
/// Builds a strongly connected component corresponding to:
/// a1 = 0
/// a2 = phi(a1, a3)
/// while (a2 != 10)
/// {
/// a3 = a2 + 4
/// }
/// </summary>
private List <SsaIdentifier> BuildScc()
{
var m = new ProcedureBuilder("test");
Identifier a = new Identifier("a", PrimitiveType.Word32, null);
m.Label("b1");
m.Assign(a, Constant.Word32(0));
m.Label("b2");
m.Assign(a, m.IAdd(a, 4));
m.BranchIf(m.Ne(a, 10), "b2");
m.Label("b3");
m.Return();
this.dom = m.Procedure.CreateBlockDominatorGraph();
var ssa = new SsaTransform(
new ProgramDataFlow(),
m.Procedure,
null,
dom,
new HashSet <RegisterStorage>());
/*
*
* proc = new Procedure("test", new Frame(PrimitiveType.Word32));
* Block b1 = proc.AddBlock("b1");
* Block b2 = proc.AddBlock("b2");
*
* Identifier a2 = new Identifier("a2", PrimitiveType.Word32, null);
* Identifier a3 = new Identifier("a3", PrimitiveType.Word32, null);
* PhiFunction phi = new PhiFunction(a1.DataType, new Expression [] { a1, a3 });
*
* Statement stm_a1 = new Statement(0, new Assignment(a1, Constant.Word32(0)), null);
* Statement stm_a2 = new Statement(0, new PhiAssignment(a2, new PhiFunction(a1.DataType, a1, a3 )), null);
* Statement stm_ex = new Statement(0, new Branch(new BinaryExpression(Operator.Ne, PrimitiveType.Bool, a2, Constant.Word32(10)), b2), null);
* Statement stm_a3 = new Statement(0, new Assignment(a3, new BinaryExpression(Operator.IAdd, a3.DataType, a2, Constant.Word32(4))), null);
* b1.Statements.Add(stm_a1);
*
* b2.Statements.Add(stm_a2);
* b2.Statements.Add(stm_a3);
*
* SsaIdentifier sid_a1 = new SsaIdentifier(a1, a1, stm_a1, ((Assignment)stm_a1.Instruction).Src, false);
* SsaIdentifier sid_a2 = new SsaIdentifier(a2, a2, stm_a2, ((PhiAssignment) stm_a2.Instruction).Src, false);
* SsaIdentifier sid_a3 = new SsaIdentifier(a3, a3, stm_a3, ((Assignment) stm_a3.Instruction).Src, false);
* sid_a1.Uses.Add(stm_a2);
* ssaIds = new SsaIdentifierCollection();
* ssaIds.Add(a1, sid_a1);
* ssaIds.Add(a2, sid_a2);
* ssaIds.Add(a3, sid_a3);
*/
ssaIds = ssa.SsaState.Identifiers;
List <SsaIdentifier> list = new List <SsaIdentifier> {
ssaIds.Where(i => i.Identifier.Name == "a_0").Single(),
ssaIds.Where(i => i.Identifier.Name == "a_1").Single(),
ssaIds.Where(i => i.Identifier.Name == "a_2").Single(),
};
return(list);
}
public void CceUnsignedRange()
{
var sExp =
#region Expected
@"r2:r2
def: def r2
uses: Mem4[0x00123400:word32] = r2
branch r2 >u 0x00000007 || r2 <u 0x00000002 mElse
branch r2 >u 0x00000007 || r2 <u 0x00000002 mElse
r1_1: orig: r1
SCZ_2: orig: SCZ
CZ_3: orig: CZ
Mem4: orig: Mem0
def: Mem4[0x00123400:word32] = r2
// ProcedureBuilder
// Return size: 0
void ProcedureBuilder(word32 r2)
ProcedureBuilder_entry:
def r2
// succ: l1
l1:
branch r2 >u 0x00000007 || r2 <u 0x00000002 mElse
// succ: mDo mElse
mDo:
Mem4[0x00123400:word32] = r2
// succ: mElse
mElse:
return
// succ: ProcedureBuilder_exit
ProcedureBuilder_exit:
";
#endregion
RunStringTest(sExp, m =>
{
var r1 = MockReg(m, 1);
var r2 = MockReg(m, 2);
var SCZ = m.Flags("SCZ");
var CZ = m.Flags("CZ");
m.Assign(r1, m.ISub(r2, 2));
m.Assign(SCZ, m.Cond(m.ISub(r1, 5)));
m.BranchIf(m.Test(ConditionCode.UGT, CZ), "mElse");
m.Label("mDo");
m.MStore(m.Word32(0x00123400), r2);
m.Label("mElse");
m.Return();
});
}
public void Pdg_PostDominateIfElse()
{
ProcedureBuilder m = new ProcedureBuilder();
m.BranchIf(m.Local32("a"), "then");
m.Assign(m.Local32("b"), m.Int32(0));
m.Jump("join");
m.Label("then");
m.Assign(m.Local32("c"), m.Int32(0));
m.Label("join");
m.Return();
FindPostDominators(m);
}
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.Ptr32, 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());
}
/// <summary>
/// Mutually recursive functions that jump into each other's bodies.
/// </summary>
/// <returns></returns>
public static Program BuildProgram()
{
var prog = new ProgramBuilder();
var m = new ProcedureBuilder("even");
var r1 = m.Register(1);
m.BranchIf(m.Eq0(r1), "done");
m.Assign(r1, m.ISub(r1, 1));
m.Call("odd", 4);
m.Assign(r1, m.Not(r1));
m.Return();
m.Label("done");
m.Assign(r1, true);
m.Return();
prog.Add(m);
m = new ProcedureBuilder("odd");
r1 = m.Register(1);
m.BranchIf(m.Eq(r1, 1), "done");
m.Assign(r1, m.ISub(r1, 1));
m.Call("event", 4);
m.Assign(r1, m.Not(r1));
m.Return();
m.Label("done");
m.Assign(r1, true);
m.Return();
prog.Add(m);
return(prog.BuildProgram());
}
public void WriteProcedure_Max()
{
var m = new ProcedureBuilder("proc");
var r1 = m.Register("r1");
var r2 = m.Register("r2");
var r3 = m.Register("r3");
m.BranchIf(m.Gt(r1, r2), "greaterthan");
m.Assign(r3,r2);
m.Assign(r2, r1);
m.Assign(r1, r3);
m.Label("greaterthan");
m.Return(r1);
hcf.Write(m.Procedure);
var sExp = @"<span class=""kw"">define</span> proc<br />
{<br />
proc_entry:<br />
<span class=""kw"">goto</span> l1<br />
greaterthan:<br />
<span class=""kw"">return</span> r1<br />
l1:<br />
<span class=""kw"">branch</span> r1 > r2 greaterthan<br />
l2:<br />
r3 = r2<br />
r2 = r1<br />
r1 = r3<br />
<span class=""kw"">goto</span> greaterthan<br />
proc_exit:<br />
}<br />
";
Debug.Write(sb.ToString());
Assert.AreEqual(sExp, sb.ToString());
}
public void Larw_do_not_span_multiple_blocks()
{
var sExp =
#region Expected
@"l1:
ax_2 = Mem0[0x0210<p16>:word16]
dx_3 = Mem0[0x0212<p16>:word16]
ax_4 = ax_2 + Mem0[0x0220<p16>:word16]
SCZ_5 = cond(ax_4)
C_6 = SLICE(SCZ_5, bool, 2) (alias)
";
#endregion
RunTest(sExp, m =>
{
m.Assign(ax, m.Mem16(m.Ptr16(0x210)));
block = m.Block;
m.Assign(dx, m.Mem16(m.Ptr16(0x212)));
m.Assign(ax, m.IAdd(ax, m.Mem16(m.Ptr16(0x0220))));
m.Assign(this.SCZ, m.Cond(ax));
m.Goto("m2");
m.Label("m2");
m.Assign(dx, m.IAdd(m.IAdd(dx, m.Mem16(m.Ptr16(0x0222))), this.CF));
});
}
private Procedure BuildSimpleLoop()
{
ProcedureBuilder m = new ProcedureBuilder();
Identifier p = m.Local32("p");
m.Assign(p, 0);
m.Label("loop");
m.BranchIf(m.Eq(p, 0x4000), "done");
m.Store(m.IAdd(p, 0x3000), m.Int32(0));
m.Assign(p, m.IAdd(p, 4));
m.Jump("loop");
m.Label("done");
m.Return();
return(m.Procedure);
}
public void SsaSwitchWithSharedBranches()
{
var m = new ProcedureBuilder("SsaSwitchWithSharedBranches");
var sp = m.Frame.EnsureRegister(m.Architecture.StackRegister);
var r1 = m.Reg32("r1", 1);
var r2 = m.Reg32("r2", 2);
var foo = new ExternalProcedure("foo", new FunctionType(
new Identifier("", VoidType.Instance, null),
new Identifier("arg1", PrimitiveType.Int32, new StackArgumentStorage(4, PrimitiveType.Int32))));
m.Assign(sp, m.Frame.FramePointer);
m.Assign(r1, m.Mem32(m.IAdd(sp, 4)));
m.BranchIf(m.Ugt(r1, m.Word32(0x5)), "m4_default");
m.Label("m1");
m.Switch(r1,
"m2", "m2", "m3", "m3", "m2", "m3");
m.Label("m2");
m.Assign(sp, m.ISub(sp, 4));
m.MStore(sp, m.Word32(0x42));
m.Call(foo, 4);
m.Assign(sp, m.IAdd(sp, 4));
// fall through
m.Label("m3");
m.Assign(sp, m.ISub(sp, 4));
m.MStore(sp, m.Word32(42));
m.Call(foo, 4);
m.Assign(sp, m.IAdd(sp, 4));
// fall through
m.Label("m4_default");
m.Assign(sp, m.ISub(sp, 4));
m.MStore(sp, m.Word32(0));
m.Call(foo, 4);
m.Assign(sp, m.IAdd(sp, 4));
m.Return();
RunUnitTest(m, "Analysis/SsaSwitchWithSharedBranches.txt");
}
public void Pdg_InfiniteLoop()
{
ProcedureBuilder m = new ProcedureBuilder();
m.Label("Infinity");
m.BranchIf(m.Eq(m.LoadW(m.Word16(0x1234)), 0), "hop");
m.SideEffect(m.Fn("foo"));
m.Label("hop");
m.BranchIf(m.Eq(m.LoadW(m.Word16(0x5123)), 1), "Infinity");
m.SideEffect(m.Fn("bar"));
m.Jump("Infinity");
m.Return();
FindPostDominators(m);
string sExp =
"hop (4): idom ProcedureBuilder_exit (6)" + nl +
"Infinity (2): idom hop (4)" + nl +
"l1 (3): idom hop (4)" + nl +
"l2 (5): idom ProcedureBuilder_exit (6)" + nl +
"ProcedureBuilder_entry (1): idom Infinity (2)" + nl +
"ProcedureBuilder_exit (6): idom " + nl;
Assert.AreEqual(sExp, sw.ToString());
}
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());
}
public void BwUnresolveableIndirect()
{
var eax = m.Reg32("eax", 0);
var esi = m.Reg32("esi", 6);
var Z = m.Frame.EnsureFlagGroup(Registers.eflags, 1, "Z", PrimitiveType.Bool);
var xfer = new RtlCall(eax, 4, InstrClass.Transfer);
m.Assign(eax, m.Mem32(esi));
m.Assign(Z, m.Cond(m.And(eax, eax)));
m.BranchIf(m.Test(ConditionCode.EQ, Z), "null_ptr");
m.Label("do_call");
var bw = new Backwalker <Block, Instruction>(host, xfer, expSimp);
Assert.IsTrue(bw.CanBackwalk());
Assert.AreEqual("eax", bw.Index.Name);
bw.BackWalk(m.Block);
Assert.AreEqual("None", bw.Index.ToString());
}
public void BwUnresolveableIndirect()
{
var eax = m.Frame.CreateTemporary("eax", PrimitiveType.Word32);
var esi = m.Frame.CreateTemporary("esi", PrimitiveType.Word32);
var Z = m.Frame.EnsureFlagGroup(1, "Z", PrimitiveType.Bool);
var xfer = new RtlCall(eax, 4, RtlClass.Transfer);
m.Assign(eax, m.LoadDw(esi));
m.Assign(Z, m.Cond(m.And(eax, eax)));
m.BranchIf(m.Test(ConditionCode.EQ, Z), "null_ptr");
m.Label("do_call");
var bw = new Backwalker(host, xfer, expSimp);
Assert.IsTrue(bw.CanBackwalk());
Assert.AreEqual("eax", bw.Index.Name);
bw.BackWalk(m.Block);
Assert.AreEqual("None", bw.Index.Name);
}
public void StrAnls_Issue_529()
{
var m = new ProcedureBuilder();
var fp = m.Frame.FramePointer;
var sp = m.Frame.EnsureRegister(m.Architecture.StackRegister);
var puts = new ExternalProcedure("puts", new FunctionType());
m.Label("m4E2");
m.Goto("m4F7");
m.Label("m4E4");
m.SideEffect(m.Fn(puts, Constant.String("Hello", StringType.NullTerminated(PrimitiveType.Byte))));
m.Return();
m.Label("m4F7");
m.BranchIf(m.Eq0(m.Mem32(m.Word32(0x0808A0A4))), "m502");
m.Label("m500");
m.Goto("m50D");
m.Label("m502");
m.BranchIf(m.Eq0(m.Mem32(m.Word32(0x0808A0A8))), "m4E4");
m.Goto("m50D");
m.Label("m50D");
m.SideEffect(m.Fn(puts, Constant.String("Goodbye", StringType.NullTerminated(PrimitiveType.Byte))));
m.Goto("m4E4");
var sExp =
#region Expected
@" if (Mem0[0x0808A0A4:word32] != 0x00 || Mem0[0x0808A0A8:word32] != 0x00)
puts(""Goodbye"");
puts(""Hello"");
return;
";
#endregion
Given_CompoundConditionCoalescer(m.Procedure);
RunTest(sExp, m.Procedure);
}
public void CrwManyPredecessorsToExitBlock()
{
var m = new ProcedureBuilder("CrwManyPredecessorsToExitBlock");
var eax = m.Frame.EnsureRegister(Registers.eax);
m.BranchIf(m.Ge0(eax), "m2Ge");
m.Label("m1Lt");
m.Assign(eax, -1);
m.Return();
m.Label("m2Ge");
m.BranchIf(m.Ne0(eax), "m4Gt");
m.Label("m3Eq");
m.Return();
m.Label("m4Gt");
m.Assign(eax, 1);
m.Return();
var flow = new ProgramDataFlow(program);
var sst = new SsaTransform(program, m.Procedure, new HashSet <Procedure>(), null, new ProgramDataFlow());
sst.Transform();
sst.AddUsesToExitBlock();
sst.SsaState.Procedure.Signature = FunctionType.Func(
new Identifier("", PrimitiveType.Word32, Registers.eax),
new Identifier("eax", PrimitiveType.Word32, Registers.eax));
var crw = new CallRewriter(this.platform, flow, new FakeDecompilerEventListener());
crw.RewriteReturns(sst.SsaState);
crw.RemoveStatementsFromExitBlock(sst.SsaState);
var sExp =
#region Expected
@"eax:eax
def: def eax
uses: branch eax >= 0<32> m2Ge
branch eax != 0<32> m4Gt
return eax
eax_2: orig: eax
def: eax_2 = 1<32>
uses: return eax_2
eax_3: orig: eax
def: eax_3 = 0xFFFFFFFF<32>
uses: return eax_3
eax_4: orig: eax
// CrwManyPredecessorsToExitBlock
// Return size: 0
word32 CrwManyPredecessorsToExitBlock(word32 eax)
CrwManyPredecessorsToExitBlock_entry:
def eax
// succ: l1
l1:
branch eax >= 0<32> m2Ge
// succ: m1Lt m2Ge
m1Lt:
eax_3 = 0xFFFFFFFF<32>
return eax_3
// succ: CrwManyPredecessorsToExitBlock_exit
m2Ge:
branch eax != 0<32> m4Gt
// succ: m3Eq m4Gt
m3Eq:
return eax
// succ: CrwManyPredecessorsToExitBlock_exit
m4Gt:
eax_2 = 1<32>
return eax_2
// succ: CrwManyPredecessorsToExitBlock_exit
CrwManyPredecessorsToExitBlock_exit:
";
#endregion
AssertExpected(sExp, sst.SsaState);
}
public void ProcStr_IfThen()
{
var r1 = m.Reg32("r1");
m.Label("head");
m.BranchIf(m.Le(r1, 0), "tail");
m.Label("doit");
m.Assign(r1, 0);
m.Label("tail");
m.Return(r1);
var sExp =
@" if (r1 > 0x00)
r1 = 0x00;
return r1;
";
RunTest(sExp, m.Procedure);
}
public void StrAnls_DoNoCleanProcedureCall()
{
m.Label("head");
m.BranchIf(m.Fn("someCheck"), "failed");
m.Goto("exit");
m.Label("failed");
m.Label("exit");
m.Return();
var sExp =
@" someCheck();
return;
";
RunTest(sExp, m.Procedure);
}
public void CceUnsignedRange()
{
var sExp =
#region Expected
@"// ProcedureBuilder
// Return size: 0
define ProcedureBuilder
ProcedureBuilder_entry:
def r2
// succ: l1
l1:
branch r2 >u 7<32> || r2 <u 2<32> mElse
// succ: mDo mElse
mDo:
Mem5[0x00123400<p32>:word32] = r2
// succ: mElse
mElse:
return
// succ: ProcedureBuilder_exit
ProcedureBuilder_exit:
";
#endregion
RunStringTest(sExp, m =>
{
var r1 = MockReg(m, 1);
var r2 = MockReg(m, 2);
var SCZ = m.Flags("SCZ");
var CZ = m.Flags("CZ");
m.Assign(r1, m.ISub(r2, 2));
m.Assign(SCZ, m.Cond(m.ISub(r1, 5)));
m.BranchIf(m.Test(ConditionCode.UGT, CZ), "mElse");
m.Label("mDo");
m.MStore(m.Ptr32(0x00123400), r2);
m.Label("mElse");
m.Return();
});
}
