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-rw-r--r--ICSharpCode.Decompiler/ILAst/PeepholeTransform.cs1103
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diff --git a/ICSharpCode.Decompiler/ILAst/PeepholeTransform.cs b/ICSharpCode.Decompiler/ILAst/PeepholeTransform.cs
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--- a/ICSharpCode.Decompiler/ILAst/PeepholeTransform.cs
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@@ -1,1103 +0,0 @@
-// Copyright (c) 2011 AlphaSierraPapa for the SharpDevelop Team
-//
-// 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 System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.Linq;
-
-using ICSharpCode.NRefactory.Utils;
-using Mono.Cecil;
-
-namespace ICSharpCode.Decompiler.ILAst
-{
- public partial class ILAstOptimizer
- {
- #region TypeConversionSimplifications
- static bool TypeConversionSimplifications(List<ILNode> body, ILExpression expr, int pos)
- {
- bool modified = false;
- modified |= TransformDecimalCtorToConstant(expr);
- modified |= SimplifyLdcI4ConvI8(expr);
- modified |= RemoveConvIFromArrayCreation(expr);
- foreach(ILExpression arg in expr.Arguments) {
- modified |= TypeConversionSimplifications(null, arg, -1);
- }
- return modified;
- }
-
- static bool TransformDecimalCtorToConstant(ILExpression expr)
- {
- MethodReference r;
- List<ILExpression> args;
- if (expr.Match(ILCode.Newobj, out r, out args) &&
- r.DeclaringType.Namespace == "System" &&
- r.DeclaringType.Name == "Decimal")
- {
- if (args.Count == 1) {
- int val;
- if (args[0].Match(ILCode.Ldc_I4, out val)) {
- expr.Code = ILCode.Ldc_Decimal;
- expr.Operand = new decimal(val);
- expr.InferredType = r.DeclaringType;
- expr.Arguments.Clear();
- return true;
- }
- } else if (args.Count == 5) {
- int lo, mid, hi, isNegative, scale;
- if (expr.Arguments[0].Match(ILCode.Ldc_I4, out lo) &&
- expr.Arguments[1].Match(ILCode.Ldc_I4, out mid) &&
- expr.Arguments[2].Match(ILCode.Ldc_I4, out hi) &&
- expr.Arguments[3].Match(ILCode.Ldc_I4, out isNegative) &&
- expr.Arguments[4].Match(ILCode.Ldc_I4, out scale))
- {
- expr.Code = ILCode.Ldc_Decimal;
- expr.Operand = new decimal(lo, mid, hi, isNegative != 0, (byte)scale);
- expr.InferredType = r.DeclaringType;
- expr.Arguments.Clear();
- return true;
- }
- }
- }
- return false;
- }
-
- static bool SimplifyLdcI4ConvI8(ILExpression expr)
- {
- ILExpression ldc;
- int val;
- if (expr.Match(ILCode.Conv_I8, out ldc) && ldc.Match(ILCode.Ldc_I4, out val)) {
- expr.Code = ILCode.Ldc_I8;
- expr.Operand = (long)val;
- expr.Arguments.Clear();
- return true;
- }
- return false;
- }
-
- static bool RemoveConvIFromArrayCreation(ILExpression expr)
- {
- TypeReference typeRef;
- ILExpression length;
- ILExpression input;
- if (expr.Match(ILCode.Newarr, out typeRef, out length)) {
- if (length.Match(ILCode.Conv_Ovf_I, out input) || length.Match(ILCode.Conv_I, out input)
- || length.Match(ILCode.Conv_Ovf_I_Un, out input) || length.Match(ILCode.Conv_U, out input))
- {
- expr.Arguments[0] = input;
- return true;
- }
- }
- return false;
- }
- #endregion
-
- #region SimplifyLdObjAndStObj
- static bool SimplifyLdObjAndStObj(List<ILNode> body, ILExpression expr, int pos)
- {
- bool modified = false;
- expr = SimplifyLdObjAndStObj(expr, ref modified);
- if (modified && body != null)
- body[pos] = expr;
- for (int i = 0; i < expr.Arguments.Count; i++) {
- expr.Arguments[i] = SimplifyLdObjAndStObj(expr.Arguments[i], ref modified);
- modified |= SimplifyLdObjAndStObj(null, expr.Arguments[i], -1);
- }
- return modified;
- }
-
- static ILExpression SimplifyLdObjAndStObj(ILExpression expr, ref bool modified)
- {
- if (expr.Code == ILCode.Initobj) {
- expr.Code = ILCode.Stobj;
- expr.Arguments.Add(new ILExpression(ILCode.DefaultValue, expr.Operand));
- modified = true;
- } else if (expr.Code == ILCode.Cpobj) {
- expr.Code = ILCode.Stobj;
- expr.Arguments[1] = new ILExpression(ILCode.Ldobj, expr.Operand, expr.Arguments[1]);
- modified = true;
- }
- ILExpression arg, arg2;
- TypeReference type;
- ILCode? newCode = null;
- if (expr.Match(ILCode.Stobj, out type, out arg, out arg2)) {
- switch (arg.Code) {
- case ILCode.Ldelema: newCode = ILCode.Stelem_Any; break;
- case ILCode.Ldloca: newCode = ILCode.Stloc; break;
- case ILCode.Ldflda: newCode = ILCode.Stfld; break;
- case ILCode.Ldsflda: newCode = ILCode.Stsfld; break;
- }
- } else if (expr.Match(ILCode.Ldobj, out type, out arg)) {
- switch (arg.Code) {
- case ILCode.Ldelema: newCode = ILCode.Ldelem_Any; break;
- case ILCode.Ldloca: newCode = ILCode.Ldloc; break;
- case ILCode.Ldflda: newCode = ILCode.Ldfld; break;
- case ILCode.Ldsflda: newCode = ILCode.Ldsfld; break;
- }
- }
- if (newCode != null) {
- arg.Code = newCode.Value;
- if (expr.Code == ILCode.Stobj) {
- arg.InferredType = expr.InferredType;
- arg.ExpectedType = expr.ExpectedType;
- arg.Arguments.Add(arg2);
- }
- arg.ILRanges.AddRange(expr.ILRanges);
- modified = true;
- return arg;
- } else {
- return expr;
- }
- }
- #endregion
-
- #region CachedDelegateInitialization
- void CachedDelegateInitializationWithField(ILBlock block, ref int i)
- {
- // if (logicnot(ldsfld(field))) {
- // stsfld(field, newobj(Action::.ctor, ldnull(), ldftn(method)))
- // } else {
- // }
- // ...(..., ldsfld(field), ...)
-
- ILCondition c = block.Body[i] as ILCondition;
- if (c == null || c.Condition == null && c.TrueBlock == null || c.FalseBlock == null)
- return;
- if (!(c.TrueBlock.Body.Count == 1 && c.FalseBlock.Body.Count == 0))
- return;
- if (!c.Condition.Match(ILCode.LogicNot))
- return;
- ILExpression condition = c.Condition.Arguments.Single() as ILExpression;
- if (condition == null || condition.Code != ILCode.Ldsfld)
- return;
- FieldDefinition field = ((FieldReference)condition.Operand).ResolveWithinSameModule(); // field is defined in current assembly
- if (field == null || !field.IsCompilerGeneratedOrIsInCompilerGeneratedClass())
- return;
- ILExpression stsfld = c.TrueBlock.Body[0] as ILExpression;
- if (!(stsfld != null && stsfld.Code == ILCode.Stsfld && ((FieldReference)stsfld.Operand).ResolveWithinSameModule() == field))
- return;
- ILExpression newObj = stsfld.Arguments[0];
- if (!(newObj.Code == ILCode.Newobj && newObj.Arguments.Count == 2))
- return;
- if (newObj.Arguments[0].Code != ILCode.Ldnull)
- return;
- if (newObj.Arguments[1].Code != ILCode.Ldftn)
- return;
- MethodDefinition anonymousMethod = ((MethodReference)newObj.Arguments[1].Operand).ResolveWithinSameModule(); // method is defined in current assembly
- if (!Ast.Transforms.DelegateConstruction.IsAnonymousMethod(context, anonymousMethod))
- return;
-
- ILNode followingNode = block.Body.ElementAtOrDefault(i + 1);
- if (followingNode != null && followingNode.GetSelfAndChildrenRecursive<ILExpression>().Count(
- e => e.Code == ILCode.Ldsfld && ((FieldReference)e.Operand).ResolveWithinSameModule() == field) == 1)
- {
- foreach (ILExpression parent in followingNode.GetSelfAndChildrenRecursive<ILExpression>()) {
- for (int j = 0; j < parent.Arguments.Count; j++) {
- if (parent.Arguments[j].Code == ILCode.Ldsfld && ((FieldReference)parent.Arguments[j].Operand).ResolveWithinSameModule() == field) {
- parent.Arguments[j] = newObj;
- block.Body.RemoveAt(i);
- i -= new ILInlining(method).InlineInto(block.Body, i, aggressive: false);
- return;
- }
- }
- }
- }
- }
-
- void CachedDelegateInitializationWithLocal(ILBlock block, ref int i)
- {
- // if (logicnot(ldloc(v))) {
- // stloc(v, newobj(Action::.ctor, ldloc(displayClass), ldftn(method)))
- // } else {
- // }
- // ...(..., ldloc(v), ...)
-
- ILCondition c = block.Body[i] as ILCondition;
- if (c == null || c.Condition == null && c.TrueBlock == null || c.FalseBlock == null)
- return;
- if (!(c.TrueBlock.Body.Count == 1 && c.FalseBlock.Body.Count == 0))
- return;
- if (!c.Condition.Match(ILCode.LogicNot))
- return;
- ILExpression condition = c.Condition.Arguments.Single() as ILExpression;
- if (condition == null || condition.Code != ILCode.Ldloc)
- return;
- ILVariable v = (ILVariable)condition.Operand;
- ILExpression stloc = c.TrueBlock.Body[0] as ILExpression;
- if (!(stloc != null && stloc.Code == ILCode.Stloc && (ILVariable)stloc.Operand == v))
- return;
- ILExpression newObj = stloc.Arguments[0];
- if (!(newObj.Code == ILCode.Newobj && newObj.Arguments.Count == 2))
- return;
- if (newObj.Arguments[0].Code != ILCode.Ldloc)
- return;
- if (newObj.Arguments[1].Code != ILCode.Ldftn)
- return;
- MethodDefinition anonymousMethod = ((MethodReference)newObj.Arguments[1].Operand).ResolveWithinSameModule(); // method is defined in current assembly
- if (!Ast.Transforms.DelegateConstruction.IsAnonymousMethod(context, anonymousMethod))
- return;
-
- ILNode followingNode = block.Body.ElementAtOrDefault(i + 1);
- if (followingNode != null && followingNode.GetSelfAndChildrenRecursive<ILExpression>().Count(
- e => e.Code == ILCode.Ldloc && (ILVariable)e.Operand == v) == 1)
- {
- ILInlining inlining = new ILInlining(method);
- if (!(inlining.numLdloc.GetOrDefault(v) == 2 && inlining.numStloc.GetOrDefault(v) == 2 && inlining.numLdloca.GetOrDefault(v) == 0))
- return;
-
- // Find the store instruction that initializes the local to null:
- foreach (ILBlock storeBlock in method.GetSelfAndChildrenRecursive<ILBlock>()) {
- for (int j = 0; j < storeBlock.Body.Count; j++) {
- ILVariable storedVar;
- ILExpression storedExpr;
- if (storeBlock.Body[j].Match(ILCode.Stloc, out storedVar, out storedExpr) && storedVar == v && storedExpr.Match(ILCode.Ldnull)) {
- // Remove the instruction
- storeBlock.Body.RemoveAt(j);
- if (storeBlock == block && j < i)
- i--;
- break;
- }
- }
- }
-
- block.Body[i] = stloc; // remove the 'if (v==null)'
- inlining = new ILInlining(method);
- inlining.InlineIfPossible(block.Body, ref i);
- }
- }
- #endregion
-
- #region MakeAssignmentExpression
- bool MakeAssignmentExpression(List<ILNode> body, ILExpression expr, int pos)
- {
- // exprVar = ...
- // stloc(v, exprVar)
- // ->
- // exprVar = stloc(v, ...))
- ILVariable exprVar;
- ILExpression initializer;
- if (!(expr.Match(ILCode.Stloc, out exprVar, out initializer) && exprVar.IsGenerated))
- return false;
- ILExpression nextExpr = body.ElementAtOrDefault(pos + 1) as ILExpression;
- ILVariable v;
- ILExpression stLocArg;
- if (nextExpr.Match(ILCode.Stloc, out v, out stLocArg) && stLocArg.MatchLdloc(exprVar)) {
- ILExpression store2 = body.ElementAtOrDefault(pos + 2) as ILExpression;
- if (StoreCanBeConvertedToAssignment(store2, exprVar)) {
- // expr_44 = ...
- // stloc(v1, expr_44)
- // anystore(v2, expr_44)
- // ->
- // stloc(v1, anystore(v2, ...))
- ILInlining inlining = new ILInlining(method);
- if (inlining.numLdloc.GetOrDefault(exprVar) == 2 && inlining.numStloc.GetOrDefault(exprVar) == 1) {
- body.RemoveAt(pos + 2); // remove store2
- body.RemoveAt(pos); // remove expr = ...
- nextExpr.Arguments[0] = store2;
- store2.Arguments[store2.Arguments.Count - 1] = initializer;
-
- inlining.InlineIfPossible(body, ref pos);
-
- return true;
- }
- }
-
- body.RemoveAt(pos + 1); // remove stloc
- nextExpr.Arguments[0] = initializer;
- ((ILExpression)body[pos]).Arguments[0] = nextExpr;
- return true;
- } else if ((nextExpr.Code == ILCode.Stsfld || nextExpr.Code == ILCode.CallSetter || nextExpr.Code == ILCode.CallvirtSetter) && nextExpr.Arguments.Count == 1) {
- // exprVar = ...
- // stsfld(fld, exprVar)
- // ->
- // exprVar = stsfld(fld, ...))
- if (nextExpr.Arguments[0].MatchLdloc(exprVar)) {
- body.RemoveAt(pos + 1); // remove stsfld
- nextExpr.Arguments[0] = initializer;
- ((ILExpression)body[pos]).Arguments[0] = nextExpr;
- return true;
- }
- }
- return false;
- }
-
- bool StoreCanBeConvertedToAssignment(ILExpression store, ILVariable exprVar)
- {
- if (store == null)
- return false;
- switch (store.Code) {
- case ILCode.Stloc:
- case ILCode.Stfld:
- case ILCode.Stsfld:
- case ILCode.Stobj:
- case ILCode.CallSetter:
- case ILCode.CallvirtSetter:
- break;
- default:
- if (!store.Code.IsStoreToArray())
- return false;
- break;
- }
- return store.Arguments.Last().Code == ILCode.Ldloc && store.Arguments.Last().Operand == exprVar;
- }
- #endregion
-
- #region MakeCompoundAssignments
- bool MakeCompoundAssignments(List<ILNode> body, ILExpression expr, int pos)
- {
- bool modified = false;
- modified |= MakeCompoundAssignment(expr);
- // Static fields and local variables are not handled here - those are expressions without side effects
- // and get handled by ReplaceMethodCallsWithOperators
- // (which does a reversible transform to the short operator form, as the introduction of checked/unchecked might have to revert to the long form).
- foreach (ILExpression arg in expr.Arguments) {
- modified |= MakeCompoundAssignments(null, arg, -1);
- }
- if (modified && body != null)
- new ILInlining(method).InlineInto(body, pos, aggressive: false);
- return modified;
- }
-
- bool MakeCompoundAssignment(ILExpression expr)
- {
- // stelem.any(T, ldloc(array), ldloc(pos), <OP>(ldelem.any(T, ldloc(array), ldloc(pos)), <RIGHT>))
- // or
- // stobj(T, ldloc(ptr), <OP>(ldobj(T, ldloc(ptr)), <RIGHT>))
- ILCode expectedLdelemCode;
- switch (expr.Code) {
- case ILCode.Stelem_Any:
- expectedLdelemCode = ILCode.Ldelem_Any;
- break;
- case ILCode.Stfld:
- expectedLdelemCode = ILCode.Ldfld;
- break;
- case ILCode.Stobj:
- expectedLdelemCode = ILCode.Ldobj;
- break;
- case ILCode.CallSetter:
- expectedLdelemCode = ILCode.CallGetter;
- break;
- case ILCode.CallvirtSetter:
- expectedLdelemCode = ILCode.CallvirtGetter;
- break;
- default:
- return false;
- }
-
- // all arguments except the last (so either array+pos, or ptr):
- bool hasGeneratedVar = false;
- for (int i = 0; i < expr.Arguments.Count - 1; i++) {
- ILVariable inputVar;
- if (!expr.Arguments[i].Match(ILCode.Ldloc, out inputVar))
- return false;
- hasGeneratedVar |= inputVar.IsGenerated;
- }
- // At least one of the variables must be generated; otherwise we just keep the expanded form.
- // We do this because we want compound assignments to be represented in ILAst only when strictly necessary;
- // other compound assignments will be introduced by ReplaceMethodCallsWithOperator
- // (which uses a reversible transformation, see ReplaceMethodCallsWithOperator.RestoreOriginalAssignOperatorAnnotation)
- if (!hasGeneratedVar)
- return false;
-
- ILExpression op = expr.Arguments.Last();
- // in case of compound assignments with a lifted operator the result is inside NullableOf and the operand is inside ValueOf
- bool liftedOperator = false;
- if (op.Code == ILCode.NullableOf) {
- op = op.Arguments[0];
- liftedOperator = true;
- }
- if (!CanBeRepresentedAsCompoundAssignment(op))
- return false;
-
- ILExpression ldelem = op.Arguments[0];
- if (liftedOperator) {
- if (ldelem.Code != ILCode.ValueOf)
- return false;
- ldelem = ldelem.Arguments[0];
- }
- if (ldelem.Code != expectedLdelemCode)
- return false;
- Debug.Assert(ldelem.Arguments.Count == expr.Arguments.Count - 1);
- for (int i = 0; i < ldelem.Arguments.Count; i++) {
- if (!ldelem.Arguments[i].MatchLdloc((ILVariable)expr.Arguments[i].Operand))
- return false;
- }
- expr.Code = ILCode.CompoundAssignment;
- expr.Operand = null;
- expr.Arguments.RemoveRange(0, ldelem.Arguments.Count);
- // result is "CompoundAssignment(<OP>(ldelem.any(...), <RIGHT>))"
- return true;
- }
-
- static bool CanBeRepresentedAsCompoundAssignment(ILExpression expr)
- {
- switch (expr.Code) {
- case ILCode.Add:
- case ILCode.Add_Ovf:
- case ILCode.Add_Ovf_Un:
- case ILCode.Sub:
- case ILCode.Sub_Ovf:
- case ILCode.Sub_Ovf_Un:
- case ILCode.Mul:
- case ILCode.Mul_Ovf:
- case ILCode.Mul_Ovf_Un:
- case ILCode.Div:
- case ILCode.Div_Un:
- case ILCode.Rem:
- case ILCode.Rem_Un:
- case ILCode.And:
- case ILCode.Or:
- case ILCode.Xor:
- case ILCode.Shl:
- case ILCode.Shr:
- case ILCode.Shr_Un:
- return true;
- case ILCode.Call:
- var m = expr.Operand as MethodReference;
- if (m == null || m.HasThis || expr.Arguments.Count != 2) return false;
- switch (m.Name) {
- case "op_Addition":
- case "op_Subtraction":
- case "op_Multiply":
- case "op_Division":
- case "op_Modulus":
- case "op_BitwiseAnd":
- case "op_BitwiseOr":
- case "op_ExclusiveOr":
- case "op_LeftShift":
- case "op_RightShift":
- return true;
- default:
- return false;
- }
- default:
- return false;
- }
- }
- #endregion
-
- #region IntroducePostIncrement
-
- bool IntroducePostIncrement(List<ILNode> body, ILExpression expr, int pos)
- {
- bool modified = IntroducePostIncrementForVariables(body, expr, pos);
- Debug.Assert(body[pos] == expr); // IntroducePostIncrementForVariables shouldn't change the expression reference
- ILExpression newExpr = IntroducePostIncrementForInstanceFields(expr);
- if (newExpr != null) {
- modified = true;
- body[pos] = newExpr;
- new ILInlining(method).InlineIfPossible(body, ref pos);
- }
- return modified;
- }
-
- bool IntroducePostIncrementForVariables(List<ILNode> body, ILExpression expr, int pos)
- {
- // Works for variables and static fields/properties
-
- // expr = ldloc(i)
- // stloc(i, add(expr, ldc.i4(1)))
- // ->
- // expr = postincrement(1, ldloca(i))
- ILVariable exprVar;
- ILExpression exprInit;
- if (!(expr.Match(ILCode.Stloc, out exprVar, out exprInit) && exprVar.IsGenerated))
- return false;
-
- //The next expression
- ILExpression nextExpr = body.ElementAtOrDefault(pos + 1) as ILExpression;
- if (nextExpr == null)
- return false;
-
- ILCode loadInstruction = exprInit.Code;
- ILCode storeInstruction = nextExpr.Code;
- bool recombineVariable = false;
-
- // We only recognise local variables, static fields, and static getters with no arguments
- switch (loadInstruction) {
- case ILCode.Ldloc:
- //Must be a matching store type
- if (storeInstruction != ILCode.Stloc)
- return false;
- ILVariable loadVar = (ILVariable)exprInit.Operand;
- ILVariable storeVar = (ILVariable)nextExpr.Operand;
- if (loadVar != storeVar) {
- if (loadVar.OriginalVariable != null && loadVar.OriginalVariable == storeVar.OriginalVariable)
- recombineVariable = true;
- else
- return false;
- }
- break;
- case ILCode.Ldsfld:
- if (storeInstruction != ILCode.Stsfld)
- return false;
- if (exprInit.Operand != nextExpr.Operand)
- return false;
- break;
- case ILCode.CallGetter:
- // non-static getters would have the 'this' argument
- if (exprInit.Arguments.Count != 0)
- return false;
- if (storeInstruction != ILCode.CallSetter)
- return false;
- if (!IsGetterSetterPair(exprInit.Operand, nextExpr.Operand))
- return false;
- break;
- default:
- return false;
- }
-
- ILExpression addExpr = nextExpr.Arguments[0];
-
- int incrementAmount;
- ILCode incrementCode = GetIncrementCode(addExpr, out incrementAmount);
- if (!(incrementAmount != 0 && addExpr.Arguments[0].MatchLdloc(exprVar)))
- return false;
-
- if (recombineVariable) {
- // Split local variable, unsplit these two instances
- // replace nextExpr.Operand with exprInit.Operand
- ReplaceVariables(method, oldVar => oldVar == nextExpr.Operand ? (ILVariable)exprInit.Operand : oldVar);
- }
-
- switch (loadInstruction) {
- case ILCode.Ldloc:
- exprInit.Code = ILCode.Ldloca;
- break;
- case ILCode.Ldsfld:
- exprInit.Code = ILCode.Ldsflda;
- break;
- case ILCode.CallGetter:
- exprInit = new ILExpression(ILCode.AddressOf, null, exprInit);
- break;
- }
- expr.Arguments[0] = new ILExpression(incrementCode, incrementAmount, exprInit);
- body.RemoveAt(pos + 1); // TODO ILRanges
- return true;
- }
-
- static bool IsGetterSetterPair(object getterOperand, object setterOperand)
- {
- MethodReference getter = getterOperand as MethodReference;
- MethodReference setter = setterOperand as MethodReference;
- if (getter == null || setter == null)
- return false;
- if (!TypeAnalysis.IsSameType(getter.DeclaringType, setter.DeclaringType))
- return false;
- MethodDefinition getterDef = getter.Resolve();
- MethodDefinition setterDef = setter.Resolve();
- if (getterDef == null || setterDef == null)
- return false;
- foreach (PropertyDefinition prop in getterDef.DeclaringType.Properties) {
- if (prop.GetMethod == getterDef)
- return prop.SetMethod == setterDef;
- }
- return false;
- }
-
- ILExpression IntroducePostIncrementForInstanceFields(ILExpression expr)
- {
- // stfld(field, ldloc(instance), add(stloc(helperVar, ldfld(field, ldloc(instance))), ldc.i4(1)))
- // -> stloc(helperVar, postincrement(1, ldflda(field, ldloc(instance))))
-
- // Also works for array elements and pointers:
-
- // stelem.any(T, ldloc(instance), ldloc(pos), add(stloc(helperVar, ldelem.any(T, ldloc(instance), ldloc(pos))), ldc.i4(1)))
- // -> stloc(helperVar, postincrement(1, ldelema(ldloc(instance), ldloc(pos))))
-
- // stobj(T, ldloc(ptr), add(stloc(helperVar, ldobj(T, ldloc(ptr)), ldc.i4(1))))
- // -> stloc(helperVar, postIncrement(1, ldloc(ptr)))
-
- // callsetter(set_P, ldloc(instance), add(stloc(helperVar, callgetter(get_P, ldloc(instance))), ldc.i4(1)))
- // -> stloc(helperVar, postIncrement(1, propertyaddress. callgetter(get_P, ldloc(instance))))
-
- if (!(expr.Code == ILCode.Stfld || expr.Code.IsStoreToArray() || expr.Code == ILCode.Stobj || expr.Code == ILCode.CallSetter || expr.Code == ILCode.CallvirtSetter))
- return null;
-
- // Test that all arguments except the last are ldloc (1 arg for fields and pointers, 2 args for arrays)
- for (int i = 0; i < expr.Arguments.Count - 1; i++) {
- if (expr.Arguments[i].Code != ILCode.Ldloc)
- return null;
- }
-
- ILExpression addExpr = expr.Arguments[expr.Arguments.Count - 1];
- int incrementAmount;
- ILCode incrementCode = GetIncrementCode(addExpr, out incrementAmount);
- ILVariable helperVar;
- ILExpression initialValue;
- if (!(incrementAmount != 0 && addExpr.Arguments[0].Match(ILCode.Stloc, out helperVar, out initialValue)))
- return null;
-
- if (expr.Code == ILCode.Stfld) {
- if (initialValue.Code != ILCode.Ldfld)
- return null;
- // There might be two different FieldReference instances, so we compare the field's signatures:
- FieldReference getField = (FieldReference)initialValue.Operand;
- FieldReference setField = (FieldReference)expr.Operand;
- if (!(TypeAnalysis.IsSameType(getField.DeclaringType, setField.DeclaringType)
- && getField.Name == setField.Name && TypeAnalysis.IsSameType(getField.FieldType, setField.FieldType)))
- {
- return null;
- }
- } else if (expr.Code == ILCode.Stobj) {
- if (!(initialValue.Code == ILCode.Ldobj && initialValue.Operand == expr.Operand))
- return null;
- } else if (expr.Code == ILCode.CallSetter) {
- if (!(initialValue.Code == ILCode.CallGetter && IsGetterSetterPair(initialValue.Operand, expr.Operand)))
- return null;
- } else if (expr.Code == ILCode.CallvirtSetter) {
- if (!(initialValue.Code == ILCode.CallvirtGetter && IsGetterSetterPair(initialValue.Operand, expr.Operand)))
- return null;
- } else {
- if (!initialValue.Code.IsLoadFromArray())
- return null;
- }
- Debug.Assert(expr.Arguments.Count - 1 == initialValue.Arguments.Count);
- for (int i = 0; i < initialValue.Arguments.Count; i++) {
- if (!initialValue.Arguments[i].MatchLdloc((ILVariable)expr.Arguments[i].Operand))
- return null;
- }
-
- ILExpression stloc = addExpr.Arguments[0];
- if (expr.Code == ILCode.Stobj) {
- stloc.Arguments[0] = new ILExpression(ILCode.PostIncrement, incrementAmount, initialValue.Arguments[0]);
- } else if (expr.Code == ILCode.CallSetter || expr.Code == ILCode.CallvirtSetter) {
- initialValue = new ILExpression(ILCode.AddressOf, null, initialValue);
- stloc.Arguments[0] = new ILExpression(ILCode.PostIncrement, incrementAmount, initialValue);
- } else {
- stloc.Arguments[0] = new ILExpression(ILCode.PostIncrement, incrementAmount, initialValue);
- initialValue.Code = (expr.Code == ILCode.Stfld ? ILCode.Ldflda : ILCode.Ldelema);
- }
- // TODO: ILRanges?
-
- return stloc;
- }
-
- ILCode GetIncrementCode(ILExpression addExpr, out int incrementAmount)
- {
- ILCode incrementCode;
- bool decrement = false;
- switch (addExpr.Code) {
- case ILCode.Add:
- incrementCode = ILCode.PostIncrement;
- break;
- case ILCode.Add_Ovf:
- incrementCode = ILCode.PostIncrement_Ovf;
- break;
- case ILCode.Add_Ovf_Un:
- incrementCode = ILCode.PostIncrement_Ovf_Un;
- break;
- case ILCode.Sub:
- incrementCode = ILCode.PostIncrement;
- decrement = true;
- break;
- case ILCode.Sub_Ovf:
- incrementCode = ILCode.PostIncrement_Ovf;
- decrement = true;
- break;
- case ILCode.Sub_Ovf_Un:
- incrementCode = ILCode.PostIncrement_Ovf_Un;
- decrement = true;
- break;
- default:
- incrementAmount = 0;
- return ILCode.Nop;
- }
- if (addExpr.Arguments[1].Match(ILCode.Ldc_I4, out incrementAmount)) {
- if (incrementAmount == -1 || incrementAmount == 1) { // TODO pointer increment?
- if (decrement)
- incrementAmount = -incrementAmount;
- return incrementCode;
- }
- }
- incrementAmount = 0;
- return ILCode.Nop;
- }
- #endregion
-
- #region IntroduceFixedStatements
- bool IntroduceFixedStatements(List<ILNode> body, int i)
- {
- ILExpression initValue;
- ILVariable pinnedVar;
- int initEndPos;
- if (!MatchFixedInitializer(body, i, out pinnedVar, out initValue, out initEndPos))
- return false;
-
- ILFixedStatement fixedStmt = body.ElementAtOrDefault(initEndPos) as ILFixedStatement;
- if (fixedStmt != null) {
- ILExpression expr = fixedStmt.BodyBlock.Body.LastOrDefault() as ILExpression;
- if (expr != null && expr.Code == ILCode.Stloc && expr.Operand == pinnedVar && IsNullOrZero(expr.Arguments[0])) {
- // we found a second initializer for the existing fixed statement
- fixedStmt.Initializers.Insert(0, initValue);
- body.RemoveRange(i, initEndPos - i);
- fixedStmt.BodyBlock.Body.RemoveAt(fixedStmt.BodyBlock.Body.Count - 1);
- if (pinnedVar.Type.IsByReference)
- pinnedVar.Type = new PointerType(((ByReferenceType)pinnedVar.Type).ElementType);
- return true;
- }
- }
-
- // find where pinnedVar is reset to 0:
- int j;
- for (j = initEndPos; j < body.Count; j++) {
- ILVariable v2;
- ILExpression storedVal;
- // stloc(pinned_Var, conv.u(ldc.i4(0)))
- if (body[j].Match(ILCode.Stloc, out v2, out storedVal) && v2 == pinnedVar) {
- if (IsNullOrZero(storedVal)) {
- break;
- }
- }
- }
- // Create fixed statement from i to j
- fixedStmt = new ILFixedStatement();
- fixedStmt.Initializers.Add(initValue);
- fixedStmt.BodyBlock = new ILBlock(body.GetRange(initEndPos, j - initEndPos)); // from initEndPos to j-1 (inclusive)
- body.RemoveRange(i + 1, Math.Min(j, body.Count - 1) - i); // from i+1 to j (inclusive)
- body[i] = fixedStmt;
- if (pinnedVar.Type.IsByReference)
- pinnedVar.Type = new PointerType(((ByReferenceType)pinnedVar.Type).ElementType);
-
- return true;
- }
-
- bool IsNullOrZero(ILExpression expr)
- {
- if (expr.Code == ILCode.Conv_U || expr.Code == ILCode.Conv_I)
- expr = expr.Arguments[0];
- return (expr.Code == ILCode.Ldc_I4 && (int)expr.Operand == 0) || expr.Code == ILCode.Ldnull;
- }
-
- bool MatchFixedInitializer(List<ILNode> body, int i, out ILVariable pinnedVar, out ILExpression initValue, out int nextPos)
- {
- if (body[i].Match(ILCode.Stloc, out pinnedVar, out initValue) && pinnedVar.IsPinned && !IsNullOrZero(initValue)) {
- initValue = (ILExpression)body[i];
- nextPos = i + 1;
- HandleStringFixing(pinnedVar, body, ref nextPos, ref initValue);
- return true;
- }
- ILCondition ifStmt = body[i] as ILCondition;
- ILExpression arrayLoadingExpr;
- if (ifStmt != null && MatchFixedArrayInitializerCondition(ifStmt.Condition, out arrayLoadingExpr)) {
- ILVariable arrayVariable = (ILVariable)arrayLoadingExpr.Operand;
- ILExpression trueValue;
- if (ifStmt.TrueBlock != null && ifStmt.TrueBlock.Body.Count == 1
- && ifStmt.TrueBlock.Body[0].Match(ILCode.Stloc, out pinnedVar, out trueValue)
- && pinnedVar.IsPinned && IsNullOrZero(trueValue))
- {
- if (ifStmt.FalseBlock != null && ifStmt.FalseBlock.Body.Count == 1 && ifStmt.FalseBlock.Body[0] is ILFixedStatement) {
- ILFixedStatement fixedStmt = (ILFixedStatement)ifStmt.FalseBlock.Body[0];
- ILVariable stlocVar;
- ILExpression falseValue;
- if (fixedStmt.Initializers.Count == 1 && fixedStmt.BodyBlock.Body.Count == 0
- && fixedStmt.Initializers[0].Match(ILCode.Stloc, out stlocVar, out falseValue) && stlocVar == pinnedVar)
- {
- ILVariable loadedVariable;
- if (falseValue.Code == ILCode.Ldelema
- && falseValue.Arguments[0].Match(ILCode.Ldloc, out loadedVariable) && loadedVariable == arrayVariable
- && IsNullOrZero(falseValue.Arguments[1]))
- {
- // OK, we detected the pattern for fixing an array.
- // Now check whether the loading expression was a store ot a temp. var
- // that can be eliminated.
- if (arrayLoadingExpr.Code == ILCode.Stloc) {
- ILInlining inlining = new ILInlining(method);
- if (inlining.numLdloc.GetOrDefault(arrayVariable) == 2 &&
- inlining.numStloc.GetOrDefault(arrayVariable) == 1 && inlining.numLdloca.GetOrDefault(arrayVariable) == 0)
- {
- arrayLoadingExpr = arrayLoadingExpr.Arguments[0];
- }
- }
- initValue = new ILExpression(ILCode.Stloc, pinnedVar, arrayLoadingExpr);
- nextPos = i + 1;
- return true;
- }
- }
- }
- }
- }
- initValue = null;
- nextPos = -1;
- return false;
- }
-
- bool MatchFixedArrayInitializerCondition(ILExpression condition, out ILExpression initValue)
- {
- ILExpression logicAnd;
- ILVariable arrayVar;
- if (condition.Match(ILCode.LogicNot, out logicAnd) && logicAnd.Code == ILCode.LogicAnd) {
- initValue = UnpackDoubleNegation(logicAnd.Arguments[0]);
- ILExpression arrayVarInitializer;
- if (initValue.Match(ILCode.Ldloc, out arrayVar)
- || initValue.Match(ILCode.Stloc, out arrayVar, out arrayVarInitializer))
- {
- ILExpression arrayLength = logicAnd.Arguments[1];
- if (arrayLength.Code == ILCode.Conv_I4)
- arrayLength = arrayLength.Arguments[0];
- return arrayLength.Code == ILCode.Ldlen && arrayLength.Arguments[0].MatchLdloc(arrayVar);
- }
- }
- initValue = null;
- return false;
- }
-
- ILExpression UnpackDoubleNegation(ILExpression expr)
- {
- ILExpression negated;
- if (expr.Match(ILCode.LogicNot, out negated) && negated.Match(ILCode.LogicNot, out negated))
- return negated;
- else
- return expr;
- }
-
- bool HandleStringFixing(ILVariable pinnedVar, List<ILNode> body, ref int pos, ref ILExpression fixedStmtInitializer)
- {
- // fixed (stloc(pinnedVar, ldloc(text))) {
- // var1 = var2 = conv.i(ldloc(pinnedVar))
- // if (logicnot(logicnot(var1))) {
- // var2 = add(var1, call(RuntimeHelpers::get_OffsetToStringData))
- // }
- // stloc(ptrVar, var2)
- // ...
-
- if (pos >= body.Count)
- return false;
-
- ILVariable var1, var2;
- ILExpression varAssignment, ptrInitialization;
- if (!(body[pos].Match(ILCode.Stloc, out var1, out varAssignment) && varAssignment.Match(ILCode.Stloc, out var2, out ptrInitialization)))
- return false;
- if (!(var1.IsGenerated && var2.IsGenerated))
- return false;
- if (ptrInitialization.Code == ILCode.Conv_I || ptrInitialization.Code == ILCode.Conv_U)
- ptrInitialization = ptrInitialization.Arguments[0];
- if (!ptrInitialization.MatchLdloc(pinnedVar))
- return false;
-
- ILCondition ifStmt = body[pos + 1] as ILCondition;
- if (!(ifStmt != null && ifStmt.TrueBlock != null && ifStmt.TrueBlock.Body.Count == 1 && (ifStmt.FalseBlock == null || ifStmt.FalseBlock.Body.Count == 0)))
- return false;
- if (!UnpackDoubleNegation(ifStmt.Condition).MatchLdloc(var1))
- return false;
- ILVariable assignedVar;
- ILExpression assignedExpr;
- if (!(ifStmt.TrueBlock.Body[0].Match(ILCode.Stloc, out assignedVar, out assignedExpr) && assignedVar == var2 && assignedExpr.Code == ILCode.Add))
- return false;
- MethodReference calledMethod;
- if (!(assignedExpr.Arguments[0].MatchLdloc(var1)))
- return false;
- if (!(assignedExpr.Arguments[1].Match(ILCode.Call, out calledMethod) || assignedExpr.Arguments[1].Match(ILCode.CallGetter, out calledMethod)))
- return false;
- if (!(calledMethod.Name == "get_OffsetToStringData" && calledMethod.DeclaringType.FullName == "System.Runtime.CompilerServices.RuntimeHelpers"))
- return false;
-
- ILVariable pointerVar;
- if (body[pos + 2].Match(ILCode.Stloc, out pointerVar, out assignedExpr) && assignedExpr.MatchLdloc(var2)) {
- pos += 3;
- fixedStmtInitializer.Operand = pointerVar;
- return true;
- }
- return false;
- }
- #endregion
-
- #region SimplifyLogicNot
- static bool SimplifyLogicNot(List<ILNode> body, ILExpression expr, int pos)
- {
- bool modified = false;
- expr = SimplifyLogicNot(expr, ref modified);
- Debug.Assert(expr == null);
- return modified;
- }
-
- static ILExpression SimplifyLogicNot(ILExpression expr, ref bool modified)
- {
- ILExpression a;
- // "ceq(a, ldc.i4.0)" becomes "logicnot(a)" if the inferred type for expression "a" is boolean
- if (expr.Code == ILCode.Ceq && TypeAnalysis.IsBoolean(expr.Arguments[0].InferredType) && (a = expr.Arguments[1]).Code == ILCode.Ldc_I4 && (int)a.Operand == 0) {
- expr.Code = ILCode.LogicNot;
- expr.ILRanges.AddRange(a.ILRanges);
- expr.Arguments.RemoveAt(1);
- modified = true;
- }
-
- ILExpression res = null;
- while (expr.Code == ILCode.LogicNot) {
- a = expr.Arguments[0];
- // remove double negation
- if (a.Code == ILCode.LogicNot) {
- res = a.Arguments[0];
- res.ILRanges.AddRange(expr.ILRanges);
- res.ILRanges.AddRange(a.ILRanges);
- expr = res;
- } else {
- if (SimplifyLogicNotArgument(expr)) res = expr = a;
- break;
- }
- }
-
- for (int i = 0; i < expr.Arguments.Count; i++) {
- a = SimplifyLogicNot(expr.Arguments[i], ref modified);
- if (a != null) {
- expr.Arguments[i] = a;
- modified = true;
- }
- }
-
- return res;
- }
-
- /// <summary>
- /// If the argument is a binary comparison operation then the negation is pushed through it
- /// </summary>
- static bool SimplifyLogicNotArgument(ILExpression expr)
- {
- var a = expr.Arguments[0];
- ILCode c;
- switch (a.Code) {
- case ILCode.Ceq: c = ILCode.Cne; break;
- case ILCode.Cne: c = ILCode.Ceq; break;
- case ILCode.Cgt: c = ILCode.Cle; break;
- case ILCode.Cgt_Un: c = ILCode.Cle_Un; break;
- case ILCode.Cge: c = ILCode.Clt; break;
- case ILCode.Cge_Un: c = ILCode.Clt_Un; break;
- case ILCode.Clt: c = ILCode.Cge; break;
- case ILCode.Clt_Un: c = ILCode.Cge_Un; break;
- case ILCode.Cle: c = ILCode.Cgt; break;
- case ILCode.Cle_Un: c = ILCode.Cgt_Un; break;
- default: return false;
- }
- a.Code = c;
- a.ILRanges.AddRange(expr.ILRanges);
- return true;
- }
- #endregion
-
- #region SimplifyShiftOperators
- static bool SimplifyShiftOperators(List<ILNode> body, ILExpression expr, int pos)
- {
- // C# compiles "a << b" to "a << (b & 31)", so we will remove the "& 31" if possible.
- bool modified = false;
- SimplifyShiftOperators(expr, ref modified);
- return modified;
- }
-
- static void SimplifyShiftOperators(ILExpression expr, ref bool modified)
- {
- for (int i = 0; i < expr.Arguments.Count; i++)
- SimplifyShiftOperators(expr.Arguments[i], ref modified);
- if (expr.Code != ILCode.Shl && expr.Code != ILCode.Shr && expr.Code != ILCode.Shr_Un)
- return;
- var a = expr.Arguments[1];
- if (a.Code != ILCode.And || a.Arguments[1].Code != ILCode.Ldc_I4 || expr.InferredType == null)
- return;
- int mask;
- switch (expr.InferredType.MetadataType) {
- case MetadataType.Int32:
- case MetadataType.UInt32: mask = 31; break;
- case MetadataType.Int64:
- case MetadataType.UInt64: mask = 63; break;
- default: return;
- }
- if ((int)a.Arguments[1].Operand != mask) return;
- var res = a.Arguments[0];
- res.ILRanges.AddRange(a.ILRanges);
- res.ILRanges.AddRange(a.Arguments[1].ILRanges);
- expr.Arguments[1] = res;
- modified = true;
- }
- #endregion
-
- #region InlineExpressionTreeParameterDeclarations
- bool InlineExpressionTreeParameterDeclarations(List<ILNode> body, ILExpression expr, int pos)
- {
- // When there is a Expression.Lambda() call, and the parameters are declared in the
- // IL statement immediately prior to the one containing the Lambda() call,
- // using this code for the3 declaration:
- // stloc(v, call(Expression::Parameter, call(Type::GetTypeFromHandle, ldtoken(...)), ldstr(...)))
- // and the variables v are assigned only once (in that statements), and read only in a Expression::Lambda
- // call that immediately follows the assignment statements, then we will inline those assignments
- // into the Lambda call using ILCode.ExpressionTreeParameterDeclarations.
-
- // This is sufficient to allow inlining over the expression tree construction. The remaining translation
- // of expression trees into C# will be performed by a C# AST transformer.
-
- for (int i = expr.Arguments.Count - 1; i >= 0; i--) {
- if (InlineExpressionTreeParameterDeclarations(body, expr.Arguments[i], pos))
- return true;
- }
-
- MethodReference mr;
- ILExpression lambdaBodyExpr, parameterArray;
- if (!(expr.Match(ILCode.Call, out mr, out lambdaBodyExpr, out parameterArray) && mr.Name == "Lambda"))
- return false;
- if (!(parameterArray.Code == ILCode.InitArray && mr.DeclaringType.FullName == "System.Linq.Expressions.Expression"))
- return false;
- int firstParameterPos = pos - parameterArray.Arguments.Count;
- if (firstParameterPos < 0)
- return false;
-
- ILExpression[] parameterInitExpressions = new ILExpression[parameterArray.Arguments.Count + 1];
- for (int i = 0; i < parameterArray.Arguments.Count; i++) {
- parameterInitExpressions[i] = body[firstParameterPos + i] as ILExpression;
- if (!MatchParameterVariableAssignment(parameterInitExpressions[i]))
- return false;
- ILVariable v = (ILVariable)parameterInitExpressions[i].Operand;
- if (!parameterArray.Arguments[i].MatchLdloc(v))
- return false;
- // TODO: validate that the variable is only used here and within 'body'
- }
-
- parameterInitExpressions[parameterInitExpressions.Length - 1] = lambdaBodyExpr;
- Debug.Assert(expr.Arguments[0] == lambdaBodyExpr);
- expr.Arguments[0] = new ILExpression(ILCode.ExpressionTreeParameterDeclarations, null, parameterInitExpressions);
-
- body.RemoveRange(firstParameterPos, parameterArray.Arguments.Count);
-
- return true;
- }
-
- bool MatchParameterVariableAssignment(ILExpression expr)
- {
- // stloc(v, call(Expression::Parameter, call(Type::GetTypeFromHandle, ldtoken(...)), ldstr(...)))
- ILVariable v;
- ILExpression init;
- if (!expr.Match(ILCode.Stloc, out v, out init))
- return false;
- if (v.IsGenerated || v.IsParameter || v.IsPinned)
- return false;
- if (v.Type == null || v.Type.FullName != "System.Linq.Expressions.ParameterExpression")
- return false;
- MethodReference parameterMethod;
- ILExpression typeArg, nameArg;
- if (!init.Match(ILCode.Call, out parameterMethod, out typeArg, out nameArg))
- return false;
- if (!(parameterMethod.Name == "Parameter" && parameterMethod.DeclaringType.FullName == "System.Linq.Expressions.Expression"))
- return false;
- MethodReference getTypeFromHandle;
- ILExpression typeToken;
- if (!typeArg.Match(ILCode.Call, out getTypeFromHandle, out typeToken))
- return false;
- if (!(getTypeFromHandle.Name == "GetTypeFromHandle" && getTypeFromHandle.DeclaringType.FullName == "System.Type"))
- return false;
- return typeToken.Code == ILCode.Ldtoken && nameArg.Code == ILCode.Ldstr;
- }
- #endregion
- }
-}
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