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1 package gnu.kawa.reflect;
2 import gnu.bytecode.*;
3 import gnu.mapping.*;
4 import gnu.expr.*;
5
6 public class InstanceOf extends Procedure2 implements CanInline, Inlineable
7 {
8 protected Language language;
9
10 public InstanceOf(Language language)
11 {
12 this.language = language;
13 }
14
15 public InstanceOf(Language language, String  name)
16 {
17 this.language = language;
18 setName(name);
19 }
20
21 public Object apply2 (Object arg1, Object arg2)
22 {
23 Type type = language.asType(arg2);
24 return language.booleanObject(type.isInstance(arg1));
25 }
26
27 static gnu.bytecode.ClassType typeType;
28 static gnu.bytecode.Method instanceMethod;
29
30 public Expression inline (ApplyExp exp, ExpWalker walker)
31 {
32 exp = Invoke.inlineClassName(exp, 1, (InlineCalls) walker);
33 Expression[] args = exp.getArgs();
34 if (args.length == 2)
35 {
36 Expression value = args[0];
37 Expression texp = args[1];
38 if (texp instanceof QuoteExp)
39 {
40 Object t = ((QuoteExp) texp).getValue();
41 if (t instanceof Type)
42 {
43 Type type = (Type) t;
44 if (value instanceof QuoteExp)
45 return type.isInstance(((QuoteExp) value).getValue())
46 ? QuoteExp.trueExp : QuoteExp.falseExp;
47 if (! value.side_effects())
48 {
49 int comp = type.compare(value.getType());
50 if (comp == 1 || comp == 0)
51 return QuoteExp.trueExp;
52 if (comp == -3)
53 return QuoteExp.falseExp;
54 }
55 }
56 }
57 }
58 return exp;
59 }
60
61 public void compile (ApplyExp exp, Compilation comp, Target target)
62 {
63 Expression[] args = exp.getArgs();
64 CodeAttr code = comp.getCode();
65 Type type = null;
66 Expression typeArg = args[1];
67 if (typeArg instanceof QuoteExp)
68 {
69 try
70 {
71 type = language.asType(((QuoteExp) typeArg).getValue());
72 }
73 catch (Exception ex)
74 {
75 comp.error('w', "unknown type spec: "+type);
76 }
77 }
78 else
79 type = language.getTypeFor(typeArg);
80 if (type != null)
81 {
82 args[0].compile(comp, Target.pushObject);
83 if (type instanceof TypeValue)
84 {
85 ((TypeValue) type).emitIsInstance(null, comp, target);
86 return;
87 }
88 else
89 type.emitIsInstance(code);
90 comp.usedClass(type);
91 }
92 else
93 {
94 if (typeType == null)
95 {
96 typeType = ClassType.make("gnu.bytecode.Type");
97 instanceMethod = typeType.addMethod("isInstance",
98 Compilation.apply1args,
99 Type.boolean_type,
100 gnu.bytecode.Access.PUBLIC);
101 }
102 args[1].compile(comp, typeType);
103 args[0].compile(comp, Target.pushObject);
104 code.emitInvokeVirtual(instanceMethod);
105 }
106 target.compileFromStack(comp, language.getTypeFor(Boolean.TYPE));
107 }
108
109 public Type getReturnType (Expression[] args)
110 {
111 return language.getTypeFor(Boolean.TYPE);
112 }
113
114 public static void emitIsInstance(TypeValue type, Variable incoming,
115 Compilation comp, Target target)
116 {
117 CodeAttr code = comp.getCode();
118 type.emitTestIf(null, null, comp);
119 ConditionalTarget cond = null;
120 if (target instanceof ConditionalTarget)
121 {
122 cond = (ConditionalTarget) target;
123 code.emitGoto(cond.ifTrue);
124 }
125 else
126 code.emitPushInt(1);
127 code.emitElse();
128 if (cond != null)
129 code.emitGoto(cond.ifFalse);
130 else
131 code.emitPushInt(0);
132 code.emitFi();
133 if (cond == null)
134 target.compileFromStack(comp,
135 comp.getLanguage().getTypeFor(Boolean.TYPE));
136 }
137 }
138 |
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