|
0
|
1 module dmd.Cast;
|
|
|
2
|
|
|
3 import dmd.Expression;
|
|
|
4 import dmd.Type;
|
|
|
5 import dmd.Loc;
|
|
|
6 import dmd.MATCH;
|
|
|
7 import dmd.IntegerExp;
|
|
|
8 import dmd.RealExp;
|
|
|
9 import dmd.ComplexExp;
|
|
|
10 import dmd.StructDeclaration;
|
|
|
11 import dmd.ArrayTypes;
|
|
|
12 import dmd.Dsymbol;
|
|
|
13 import dmd.VarDeclaration;
|
|
|
14 import dmd.StructLiteralExp;
|
|
|
15 import dmd.Util;
|
|
|
16 import dmd.TY;
|
|
|
17 import dmd.TOK;
|
|
|
18 import dmd.GlobalExpressions;
|
|
|
19
|
|
|
20 import dmd.Complex;
|
|
|
21
|
|
|
22 Expression expType(Type type, Expression e)
|
|
|
23 {
|
|
|
24 if (type !is e.type)
|
|
|
25 {
|
|
|
26 e = e.copy();
|
|
|
27 e.type = type;
|
|
|
28 }
|
|
|
29 return e;
|
|
|
30 }
|
|
|
31
|
|
|
32 /* Also returns EXP_CANT_INTERPRET if cannot be computed.
|
|
|
33 * to: type to cast to
|
|
|
34 * type: type to paint the result
|
|
|
35 */
|
|
|
36
|
|
|
37 Expression Cast(Type type, Type to, Expression e1)
|
|
|
38 {
|
|
|
39 Expression e = EXP_CANT_INTERPRET;
|
|
|
40 Loc loc = e1.loc;
|
|
|
41
|
|
|
42 //printf("Cast(type = %s, to = %s, e1 = %s)\n", type.toChars(), to.toChars(), e1.toChars());
|
|
|
43 //printf("\te1.type = %s\n", e1.type.toChars());
|
|
|
44 if (e1.type.equals(type) && type.equals(to))
|
|
|
45 return e1;
|
|
|
46 if (e1.type.implicitConvTo(to) >= MATCH.MATCHconst || to.implicitConvTo(e1.type) >= MATCH.MATCHconst)
|
|
|
47 return expType(to, e1);
|
|
|
48
|
|
|
49 Type tb = to.toBasetype();
|
|
|
50 Type typeb = type.toBasetype();
|
|
|
51
|
|
|
52 /* Allow casting from one string type to another
|
|
|
53 */
|
|
|
54 if (e1.op == TOK.TOKstring)
|
|
|
55 {
|
|
|
56 if (tb.ty == TY.Tarray && typeb.ty == TY.Tarray &&
|
|
|
57 tb.nextOf().size() == typeb.nextOf().size())
|
|
|
58 {
|
|
|
59 return expType(to, e1);
|
|
|
60 }
|
|
|
61 }
|
|
|
62
|
|
|
63 if (e1.isConst() != 1)
|
|
|
64 return EXP_CANT_INTERPRET;
|
|
|
65
|
|
|
66 if (tb.ty == TY.Tbool)
|
|
|
67 e = new IntegerExp(loc, e1.toInteger() != 0, type);
|
|
|
68 else if (type.isintegral())
|
|
|
69 {
|
|
|
70 if (e1.type.isfloating())
|
|
|
71 {
|
|
|
72 long result;
|
|
|
73 real r = e1.toReal();
|
|
|
74
|
|
|
75 switch (typeb.ty)
|
|
|
76 {
|
|
|
77 case TY.Tint8: result = cast(byte)r; break;
|
|
|
78 case TY.Tchar:
|
|
|
79 case TY.Tuns8: result = cast(ubyte)r; break;
|
|
|
80 case TY.Tint16: result = cast(short)r; break;
|
|
|
81 case TY.Twchar:
|
|
|
82 case TY.Tuns16: result = cast(ushort)r; break;
|
|
|
83 case TY.Tint32: result = cast(int)r; break;
|
|
|
84 case TY.Tdchar:
|
|
|
85 case TY.Tuns32: result = cast(uint)r; break;
|
|
|
86 case TY.Tint64: result = cast(long)r; break;
|
|
|
87 case TY.Tuns64: result = cast(ulong)r; break;
|
|
|
88 }
|
|
|
89
|
|
|
90 e = new IntegerExp(loc, result, type);
|
|
|
91 }
|
|
|
92 else if (type.isunsigned())
|
|
|
93 e = new IntegerExp(loc, e1.toUInteger(), type);
|
|
|
94 else
|
|
|
95 e = new IntegerExp(loc, e1.toInteger(), type);
|
|
|
96 }
|
|
|
97 else if (tb.isreal())
|
|
|
98 {
|
|
|
99 real value = e1.toReal();
|
|
|
100 e = new RealExp(loc, value, type);
|
|
|
101 }
|
|
|
102 else if (tb.isimaginary())
|
|
|
103 {
|
|
|
104 real value = e1.toImaginary();
|
|
|
105 e = new RealExp(loc, value, type);
|
|
|
106 }
|
|
|
107 else if (tb.iscomplex())
|
|
|
108 {
|
|
|
109 Complex!(real) value = e1.toComplex();
|
|
|
110 e = new ComplexExp(loc, value, type);
|
|
|
111 }
|
|
|
112 else if (tb.isscalar())
|
|
|
113 e = new IntegerExp(loc, e1.toInteger(), type);
|
|
|
114 else if (tb.ty == TY.Tvoid)
|
|
|
115 e = EXP_CANT_INTERPRET;
|
|
|
116 else if (tb.ty == TY.Tstruct && e1.op == TOK.TOKint64)
|
|
|
117 {
|
|
|
118 // Struct = 0;
|
|
|
119 StructDeclaration sd = tb.toDsymbol(null).isStructDeclaration();
|
|
|
120 assert(sd);
|
|
|
121 Expressions elements = new Expressions;
|
|
|
122 for (size_t i = 0; i < sd.fields.dim; i++)
|
|
|
123 { Dsymbol s = cast(Dsymbol)sd.fields.data[i];
|
|
|
124 VarDeclaration v = s.isVarDeclaration();
|
|
|
125 assert(v);
|
|
|
126
|
|
|
127 Expression exp = new IntegerExp(0);
|
|
|
128 exp = Cast(v.type, v.type, exp);
|
|
|
129 if (exp == EXP_CANT_INTERPRET)
|
|
|
130 return exp;
|
|
|
131 elements.push(cast(void*)exp);
|
|
|
132 }
|
|
|
133 e = new StructLiteralExp(loc, sd, elements);
|
|
|
134 e.type = type;
|
|
|
135 }
|
|
|
136 else
|
|
|
137 {
|
|
|
138 error(loc, "cannot cast %s to %s", e1.type.toChars(), type.toChars());
|
|
|
139 e = new IntegerExp(loc, 0, Type.tint32);
|
|
|
140 }
|
|
|
141 return e;
|
|
|
142 } |
