Jo Shields a575963da9 Imported Upstream version 3.6.0
Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14
2014-08-13 10:39:27 +01:00

127 lines
3.8 KiB
C#

//
// 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.
//
// Copyright (C) Lluis Sanchez Gual, 2004
//
#if !FULL_AOT_RUNTIME
using System;
using System.Collections;
using System.Reflection;
using System.Reflection.Emit;
namespace Mono.CodeGeneration
{
public class CodeForeach: CodeStatement
{
Type itemType;
CodeExpression array;
CodeBlock forBlock;
CodeVariableDeclaration itemDec;
public CodeForeach (CodeExpression array, Type itemType)
{
this.array = array;
this.itemType = itemType;
Type t = array.GetResultType ();
if (!t.IsArray && t.GetMethod ("GetEnumerator", Type.EmptyTypes) == null)
throw new InvalidOperationException ("foreach statement cannot operate on variables of type `" + t + "' because that class does not provide a GetEnumerator method or it is inaccessible");
itemDec = new CodeVariableDeclaration (itemType, "item");
}
public CodeValueReference ItemExpression
{
get { return itemDec.Variable; }
}
public CodeBlock ForBlock
{
get { return forBlock; }
set { forBlock = value; }
}
public override void Generate (ILGenerator gen)
{
Type t = array.GetResultType ();
if (t.IsArray)
{
CodeBlock block = new CodeBlock();
CodeVariableDeclaration indexDec;
CodeWhile cw;
CodeValueReference index;
CodeValueReference item;
block.Add (itemDec);
item = itemDec.Variable;
block.Add (indexDec = new CodeVariableDeclaration (typeof(int), "n"));
index = indexDec.Variable;
block.Add (new CodeAssignment (index, new CodeLiteral (0)));
block.Add (cw = new CodeWhile (CodeExpression.IsSmallerThan (index, array.ArrayLength)));
CodeBlock loopBlock = new CodeBlock ();
loopBlock.Add (new CodeAssignment (item, array[index]));
loopBlock.Add (new CodeIncrement(index));
loopBlock.Add (forBlock);
cw.WhileBlock = loopBlock;
block.Generate (gen);
}
else
{
CodeBlock block = new CodeBlock();
CodeVariableDeclaration dec;
CodeWhile cw;
CodeValueReference enumerator;
CodeValueReference item;
block.Add (itemDec);
item = itemDec.Variable;
block.Add (dec = new CodeVariableDeclaration (typeof(IEnumerator), "e"));
enumerator = dec.Variable;
block.Add (new CodeAssignment (enumerator, array.Call("GetEnumerator")));
block.Add (cw = new CodeWhile (enumerator.Call ("MoveNext")));
CodeBlock loopBlock = new CodeBlock ();
loopBlock.Add (new CodeAssignment (item, enumerator["Current"]));
loopBlock.Add (forBlock);
cw.WhileBlock = loopBlock;
block.Generate (gen);
}
}
public override void PrintCode (CodeWriter cp)
{
cp.Write ("foreach (" + itemType + " item in ");
array.PrintCode (cp);
cp.Write (") {");
cp.EndLine ();
cp.Indent ();
forBlock.PrintCode (cp);
cp.Unindent ();
cp.BeginLine ().Write ("}");
}
}
}
#endif