mcs/tools/linker/Mono.Linker.Steps/SweepStep.cs

   1 //
   2 // SweepStep.cs
   3 //
   4 // Author:
   5 //   Jb Evain (jbevain@gmail.com)
   6 //
   7 // (C) 2006 Jb Evain
   8 // (C) 2007 Novell, Inc.
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Collections;
  31
  32 using Mono.Cecil;
  33
  34 namespace Mono.Linker.Steps {
  35
  36         public class SweepStep : IStep {
  37
  38                 AssemblyDefinition [] assemblies;
  39
  40                 public void Process (LinkContext context)
  41                 {
  42                         assemblies = context.GetAssemblies ();
  43                         foreach (var assembly in assemblies)
  44                                 SweepAssembly (assembly);
  45                 }
  46
  47                 void SweepAssembly (AssemblyDefinition assembly)
  48                 {
  49                         if (Annotations.GetAction (assembly) != AssemblyAction.Link)
  50                                 return;
  51
  52                         if (!IsMarkedAssembly (assembly)) {
  53                                 RemoveAssembly (assembly);
  54                                 return;
  55                         }
  56
  57                         var types = assembly.MainModule.Types;
  58                         var cloned_types = Clone (types);
  59
  60                         types.Clear ();
  61
  62                         foreach (TypeDefinition type in cloned_types) {
  63                                 if (Annotations.IsMarked (type)) {
  64                                         SweepType (type);
  65                                         types.Add (type);
  66                                         continue;
  67                                 }
  68
  69                                 SweepReferences (assembly, type);
  70                         }
  71                 }
  72
  73                 static bool IsMarkedAssembly (AssemblyDefinition assembly)
  74                 {
  75                         return Annotations.IsMarked (assembly.MainModule);
  76                 }
  77
  78                 void RemoveAssembly (AssemblyDefinition assembly)
  79                 {
  80                         Annotations.SetAction (assembly, AssemblyAction.Delete);
  81
  82                         SweepReferences (assembly);
  83                 }
  84
  85                 void SweepReferences (AssemblyDefinition target)
  86                 {
  87                         foreach (var assembly in assemblies)
  88                                 SweepReferences (assembly, target);
  89                 }
  90
  91                 void SweepReferences (AssemblyDefinition assembly, AssemblyDefinition target)
  92                 {
  93                         var references = assembly.MainModule.AssemblyReferences;
  94                         for (int i = 0; i < references.Count; i++) {
  95                                 var reference = references [i];
  96                                 if (!AreSameReference (reference, target.Name))
  97                                         continue;
  98
  99                                 references.RemoveAt (i);
 100                                 return;
 101                         }
 102                 }
 103
 104                 static ICollection Clone (ICollection collection)
 105                 {
 106                         return new ArrayList (collection);
 107                 }
 108
 109                 void SweepReferences (AssemblyDefinition assembly, TypeDefinition type)
 110                 {
 111                         foreach (AssemblyDefinition asm in assemblies) {
 112                                 ModuleDefinition module = asm.MainModule;
 113                                 if (!module.TypeReferences.Contains (type))
 114                                         continue;
 115
 116                                 TypeReference typeRef = module.TypeReferences [type.FullName];
 117                                 if (AssemblyMatch (assembly, typeRef)) {
 118                                         SweepMemberReferences (module, typeRef);
 119                                         module.TypeReferences.Remove (typeRef);
 120                                 }
 121                         }
 122                 }
 123
 124                 static void SweepMemberReferences (ModuleDefinition module, TypeReference reference)
 125                 {
 126                         var references = module.MemberReferences;
 127
 128                         for (int i = 0; i < references.Count; i++) {
 129                                 if (references [i].DeclaringType == reference)
 130                                         references.RemoveAt (i--);
 131                         }
 132                 }
 133
 134                 static bool AssemblyMatch (AssemblyDefinition assembly, TypeReference type)
 135                 {
 136                         AssemblyNameReference reference = type.Scope as AssemblyNameReference;
 137                         if (reference == null)
 138                                 return false;
 139
 140                         return AreSameReference (assembly.Name, reference);
 141                 }
 142
 143                 static void SweepType (TypeDefinition type)
 144                 {
 145                         if (type.HasFields)
 146                                 SweepCollection (type.Fields);
 147
 148                         if (type.HasConstructors)
 149                                 SweepCollection (type.Constructors);
 150
 151                         if (type.HasMethods)
 152                                 SweepCollection (type.Methods);
 153                 }
 154
 155                 static void SweepCollection (IList list)
 156                 {
 157                         for (int i = 0; i < list.Count; i++)
 158                                 if (!Annotations.IsMarked ((IAnnotationProvider) list [i]))
 159                                         list.RemoveAt (i--);
 160                 }
 161
 162                 static bool AreSameReference (AssemblyNameReference a, AssemblyNameReference b)
 163                 {
 164                         if (a == b)
 165                                 return true;
 166
 167                         if (a.Name != b.Name)
 168                                 return false;
 169
 170                         if (a.Version != b.Version)
 171                                 return false;
 172
 173                         return true;
 174                 }
 175         }
 176 }