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annotate dmd2/builtin.c @ 1578:1dee66f6ec0b

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Removed a chunk of code in favour of a shorter and more portable method
author Robert Clipsham <robert@octarineparrot.com>
date Tue, 08 Sep 2009 11:21:30 +0100
parents 638d16625da2
children
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1
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2 // Compiler implementation of the D programming language
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3 // Copyright (c) 1999-2009 by Digital Mars
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4 // All Rights Reserved
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5 // written by Walter Bright
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6 // http://www.digitalmars.com
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7 // License for redistribution is by either the Artistic License
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8 // in artistic.txt, or the GNU General Public License in gnu.txt.
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9 // See the included readme.txt for details.
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11 #include <stdio.h>
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12 #include <assert.h>
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13 #include <math.h>
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14
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15 #include "mars.h"
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16 #include "declaration.h"
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17 #include "attrib.h"
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18 #include "expression.h"
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19 #include "scope.h"
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20 #include "mtype.h"
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21 #include "aggregate.h"
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22 #include "identifier.h"
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23 #include "id.h"
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24 #include "module.h"
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25
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26 #if DMDV2
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27
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28 /**********************************
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29 * Determine if function is a builtin one that we can
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30 * evaluate at compile time.
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31 */
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32 enum BUILTIN FuncDeclaration::isBuiltin()
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33 {
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34 static const char FeZe[] = "FNaNbeZe"; // pure nothrow real function(real)
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35
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36 //printf("FuncDeclaration::isBuiltin() %s\n", toChars());
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37 if (builtin == BUILTINunknown)
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38 {
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39 builtin = BUILTINnot;
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40 if (parent && parent->isModule())
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41 {
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42 // If it's in the std.math package
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43 if (parent->ident == Id::math &&
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44 parent->parent && parent->parent->ident == Id::std &&
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45 !parent->parent->parent)
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46 {
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47 //printf("deco = %s\n", type->deco);
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48 if (strcmp(type->deco, FeZe) == 0)
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49 {
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50 if (ident == Id::sin)
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51 builtin = BUILTINsin;
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52 else if (ident == Id::cos)
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53 builtin = BUILTINcos;
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54 else if (ident == Id::tan)
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55 builtin = BUILTINtan;
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56 else if (ident == Id::_sqrt)
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57 builtin = BUILTINsqrt;
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58 else if (ident == Id::fabs)
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59 builtin = BUILTINfabs;
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60 //printf("builtin = %d\n", builtin);
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61 }
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62 // if float or double versions
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63 else if (strcmp(type->deco, "FNaNbdZd") == 0 ||
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64 strcmp(type->deco, "FNaNbfZf") == 0)
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65 {
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66 if (ident == Id::_sqrt)
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67 builtin = BUILTINsqrt;
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68 }
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69 }
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70 }
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71 }
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72 return builtin;
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73 }
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74
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75
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76 /**************************************
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77 * Evaluate builtin function.
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78 * Return result; NULL if cannot evaluate it.
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79 */
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80
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81 Expression *eval_builtin(enum BUILTIN builtin, Expressions *arguments)
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82 {
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83 assert(arguments && arguments->dim);
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84 Expression *arg0 = (Expression *)arguments->data[0];
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85 Expression *e = NULL;
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86 switch (builtin)
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87 {
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88 case BUILTINsin:
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89 if (arg0->op == TOKfloat64)
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90 e = new RealExp(0, sinl(arg0->toReal()), arg0->type);
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91 break;
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92
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93 case BUILTINcos:
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94 if (arg0->op == TOKfloat64)
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95 e = new RealExp(0, cosl(arg0->toReal()), arg0->type);
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96 break;
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97
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98 case BUILTINtan:
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99 if (arg0->op == TOKfloat64)
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100 e = new RealExp(0, tanl(arg0->toReal()), arg0->type);
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101 break;
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102
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103 case BUILTINsqrt:
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104 if (arg0->op == TOKfloat64)
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105 e = new RealExp(0, sqrtl(arg0->toReal()), arg0->type);
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106 break;
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107
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108 case BUILTINfabs:
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109 if (arg0->op == TOKfloat64)
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110 e = new RealExp(0, fabsl(arg0->toReal()), arg0->type);
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111 break;
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112 }
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113 return e;
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114 }
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115
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116 #endif