.NET Decompiler with support for PDB generation, ReadyToRun, Metadata (&more) - cross-platform!
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 

517 lines
13 KiB

// Copyright (c) 2014 Daniel Grunwald
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
using ICSharpCode.Decompiler.TypeSystem;
namespace ICSharpCode.Decompiler.IL
{
partial class ILInstruction
{
public bool MatchLdcI4(int val)
{
return OpCode == OpCode.LdcI4 && ((LdcI4)this).Value == val;
}
public bool MatchLdcF4(float value)
{
return MatchLdcF4(out var v) && v == value;
}
public bool MatchLdcF8(double value)
{
return MatchLdcF8(out var v) && v == value;
}
/// <summary>
/// Matches ldc.i4, ldc.i8, and extending conversions.
/// </summary>
public bool MatchLdcI(out long val)
{
if (MatchLdcI8(out val))
return true;
if (MatchLdcI4(out int intVal)) {
val = intVal;
return true;
}
if (this is Conv conv) {
if (conv.Kind == ConversionKind.SignExtend) {
return conv.Argument.MatchLdcI(out val);
} else if (conv.Kind == ConversionKind.ZeroExtend && conv.InputType == StackType.I4) {
if (conv.Argument.MatchLdcI(out val)) {
// clear top 32 bits
val &= uint.MaxValue;
return true;
}
}
}
return false;
}
public bool MatchLdcI(long val)
{
return MatchLdcI(out long v) && v == val;
}
public bool MatchLdLoc(ILVariable variable)
{
var inst = this as LdLoc;
return inst != null && inst.Variable == variable;
}
public bool MatchLdLoca(ILVariable variable)
{
var inst = this as LdLoca;
return inst != null && inst.Variable == variable;
}
/// <summary>
/// Matches either ldloc (if the variable is a reference type), or ldloca (otherwise).
/// </summary>
public bool MatchLdLocRef(ILVariable variable)
{
return MatchLdLocRef(out var v) && v == variable;
}
/// <summary>
/// Matches either ldloc (if the variable is a reference type), or ldloca (otherwise).
/// </summary>
public bool MatchLdLocRef(out ILVariable variable)
{
switch (this) {
case LdLoc ldloc:
variable = ldloc.Variable;
return variable.Type.IsReferenceType == true;
case LdLoca ldloca:
variable = ldloca.Variable;
return variable.Type.IsReferenceType != true || variable.Type.Kind == TypeKind.TypeParameter;
default:
variable = null;
return false;
}
}
public bool MatchLdThis()
{
var inst = this as LdLoc;
return inst != null && inst.Variable.Kind == VariableKind.Parameter && inst.Variable.Index < 0;
}
public bool MatchStLoc(out ILVariable variable)
{
var inst = this as StLoc;
if (inst != null) {
variable = inst.Variable;
return true;
}
variable = null;
return false;
}
public bool MatchStLoc(ILVariable variable, out ILInstruction value)
{
var inst = this as StLoc;
if (inst != null && inst.Variable == variable) {
value = inst.Value;
return true;
}
value = null;
return false;
}
public bool MatchLdLen(StackType type, out ILInstruction array)
{
var inst = this as LdLen;
if (inst != null && inst.ResultType == type) {
array = inst.Array;
return true;
}
array = null;
return false;
}
public bool MatchReturn(out ILInstruction value)
{
var inst = this as Leave;
if (inst != null && inst.IsLeavingFunction) {
value = inst.Value;
return true;
}
value = default(ILInstruction);
return false;
}
public bool MatchBranch(out Block targetBlock)
{
var inst = this as Branch;
if (inst != null) {
targetBlock = inst.TargetBlock;
return true;
}
targetBlock = null;
return false;
}
public bool MatchBranch(Block targetBlock)
{
var inst = this as Branch;
return inst != null && inst.TargetBlock == targetBlock;
}
public bool MatchLeave(out BlockContainer targetContainer, out ILInstruction value)
{
var inst = this as Leave;
if (inst != null) {
targetContainer = inst.TargetContainer;
value = inst.Value;
return true;
}
targetContainer = null;
value = null;
return false;
}
public bool MatchLeave(BlockContainer targetContainer, out ILInstruction value)
{
var inst = this as Leave;
if (inst != null && targetContainer == inst.TargetContainer) {
value = inst.Value;
return true;
}
value = null;
return false;
}
public bool MatchLeave(out BlockContainer targetContainer)
{
var inst = this as Leave;
if (inst != null && inst.Value.MatchNop()) {
targetContainer = inst.TargetContainer;
return true;
}
targetContainer = null;
return false;
}
public bool MatchLeave(BlockContainer targetContainer)
{
var inst = this as Leave;
return inst != null && inst.TargetContainer == targetContainer && inst.Value.MatchNop();
}
public bool MatchIfInstruction(out ILInstruction condition, out ILInstruction trueInst, out ILInstruction falseInst)
{
var inst = this as IfInstruction;
if (inst != null) {
condition = inst.Condition;
trueInst = inst.TrueInst;
falseInst = inst.FalseInst;
return true;
}
condition = null;
trueInst = null;
falseInst = null;
return false;
}
public bool MatchIfInstructionPositiveCondition(out ILInstruction condition, out ILInstruction trueInst, out ILInstruction falseInst)
{
if (MatchIfInstruction(out condition, out trueInst, out falseInst)) {
// Swap trueInst<>falseInst for every logic.not in the condition.
while (condition.MatchLogicNot(out var arg)) {
condition = arg;
ILInstruction tmp = trueInst;
trueInst = falseInst;
falseInst = tmp;
}
return true;
}
return false;
}
/// <summary>
/// Matches an if instruction where the false instruction is a nop.
/// </summary>
public bool MatchIfInstruction(out ILInstruction condition, out ILInstruction trueInst)
{
var inst = this as IfInstruction;
if (inst != null && inst.FalseInst.MatchNop()) {
condition = inst.Condition;
trueInst = inst.TrueInst;
return true;
}
condition = null;
trueInst = null;
return false;
}
/// <summary>
/// Matches a 'logic and' instruction ("if (a) b else ldc.i4 0").
/// Note: unlike C# '&amp;&amp;', this instruction is not limited to booleans,
/// but allows passing through arbitrary I4 values on the rhs (but not on the lhs).
/// </summary>
public bool MatchLogicAnd(out ILInstruction lhs, out ILInstruction rhs)
{
var inst = this as IfInstruction;
if (inst != null && inst.FalseInst.MatchLdcI4(0)) {
lhs = inst.Condition;
rhs = inst.TrueInst;
return true;
}
lhs = null;
rhs = null;
return false;
}
/// <summary>
/// Matches a 'logic or' instruction ("if (a) ldc.i4 1 else b").
/// Note: unlike C# '||', this instruction is not limited to booleans,
/// but allows passing through arbitrary I4 values on the rhs (but not on the lhs).
/// </summary>
public bool MatchLogicOr(out ILInstruction lhs, out ILInstruction rhs)
{
var inst = this as IfInstruction;
if (inst != null && inst.TrueInst.MatchLdcI4(1)) {
lhs = inst.Condition;
rhs = inst.FalseInst;
return true;
}
lhs = null;
rhs = null;
return false;
}
/// <summary>
/// Matches an logical negation.
/// </summary>
public bool MatchLogicNot(out ILInstruction arg)
{
if (this is Comp comp && comp.Kind == ComparisonKind.Equality
&& comp.LiftingKind == ComparisonLiftingKind.None
&& comp.Right.MatchLdcI4(0)) {
arg = comp.Left;
return true;
}
arg = null;
return false;
}
public bool MatchTryCatchHandler(out ILVariable variable)
{
var inst = this as TryCatchHandler;
if (inst != null) {
variable = inst.Variable;
return true;
}
variable = null;
return false;
}
/// <summary>
/// Matches comp(left == right) or logic.not(comp(left != right)).
/// </summary>
public bool MatchCompEquals(out ILInstruction left, out ILInstruction right)
{
ILInstruction thisInst = this;
var compKind = ComparisonKind.Equality;
while (thisInst.MatchLogicNot(out var arg) && arg is Comp) {
thisInst = arg;
if (compKind == ComparisonKind.Equality)
compKind = ComparisonKind.Inequality;
else
compKind = ComparisonKind.Equality;
}
if (thisInst is Comp comp && comp.Kind == compKind && !comp.IsLifted) {
left = comp.Left;
right = comp.Right;
return true;
} else {
left = null;
right = null;
return false;
}
}
/// <summary>
/// Matches 'comp(arg == ldnull)'
/// </summary>
public bool MatchCompEqualsNull(out ILInstruction arg)
{
if (!MatchCompEquals(out var left, out var right)) {
arg = null;
return false;
}
if (right.MatchLdNull()) {
arg = left;
return true;
} else if (left.MatchLdNull()) {
arg = right;
return true;
} else {
arg = null;
return false;
}
}
/// <summary>
/// Matches 'comp(arg != ldnull)'
/// </summary>
public bool MatchCompNotEqualsNull(out ILInstruction arg)
{
if (!MatchCompNotEquals(out var left, out var right)) {
arg = null;
return false;
}
if (right.MatchLdNull()) {
arg = left;
return true;
} else if (left.MatchLdNull()) {
arg = right;
return true;
} else {
arg = null;
return false;
}
}
/// <summary>
/// Matches comp(left != right) or logic.not(comp(left == right)).
/// </summary>
public bool MatchCompNotEquals(out ILInstruction left, out ILInstruction right)
{
ILInstruction thisInst = this;
var compKind = ComparisonKind.Inequality;
while (thisInst.MatchLogicNot(out var arg) && arg is Comp) {
thisInst = arg;
if (compKind == ComparisonKind.Equality)
compKind = ComparisonKind.Inequality;
else
compKind = ComparisonKind.Equality;
}
if (thisInst is Comp comp && comp.Kind == compKind && !comp.IsLifted) {
left = comp.Left;
right = comp.Right;
return true;
} else {
left = null;
right = null;
return false;
}
}
public bool MatchLdFld(out ILInstruction target, out IField field)
{
if (this is LdObj ldobj && ldobj.Target is LdFlda ldflda && ldobj.UnalignedPrefix == 0 && !ldobj.IsVolatile) {
field = ldflda.Field;
if (field.DeclaringType.IsReferenceType == true || !ldflda.Target.MatchAddressOf(out target, out _)) {
target = ldflda.Target;
}
return true;
}
target = null;
field = null;
return false;
}
public bool MatchLdsFld(out IField field)
{
if (this is LdObj ldobj && ldobj.Target is LdsFlda ldsflda && ldobj.UnalignedPrefix == 0 && !ldobj.IsVolatile) {
field = ldsflda.Field;
return true;
}
field = null;
return false;
}
public bool MatchLdsFld(IField field)
{
return MatchLdsFld(out var f) && f.Equals(field);
}
public bool MatchStsFld(out IField field, out ILInstruction value)
{
if (this is StObj stobj && stobj.Target is LdsFlda ldsflda && stobj.UnalignedPrefix == 0 && !stobj.IsVolatile) {
field = ldsflda.Field;
value = stobj.Value;
return true;
}
field = null;
value = null;
return false;
}
public bool MatchStFld(out ILInstruction target, out IField field, out ILInstruction value)
{
if (this is StObj stobj && stobj.Target is LdFlda ldflda && stobj.UnalignedPrefix == 0 && !stobj.IsVolatile) {
target = ldflda.Target;
field = ldflda.Field;
value = stobj.Value;
return true;
}
target = null;
field = null;
value = null;
return false;
}
public bool MatchBinaryNumericInstruction(BinaryNumericOperator @operator)
{
var op = this as BinaryNumericInstruction;
return op != null && op.Operator == @operator;
}
public bool MatchBinaryNumericInstruction(BinaryNumericOperator @operator, out ILInstruction left, out ILInstruction right)
{
var op = this as BinaryNumericInstruction;
if (op != null && op.Operator == @operator) {
left = op.Left;
right = op.Right;
return true;
}
left = null;
right = null;
return false;
}
public bool MatchBinaryNumericInstruction(out BinaryNumericOperator @operator, out ILInstruction left, out ILInstruction right)
{
var op = this as BinaryNumericInstruction;
if (op != null) {
@operator = op.Operator;
left = op.Left;
right = op.Right;
return true;
}
@operator = BinaryNumericOperator.None;
left = null;
right = null;
return false;
}
/// <summary>
/// If this instruction is a conversion of the specified kind, return its argument.
/// Otherwise, return the instruction itself.
/// </summary>
/// <remarks>
/// Does not unwrap lifted conversions.
/// </remarks>
public virtual ILInstruction UnwrapConv(ConversionKind kind)
{
return this;
}
}
}