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Fix FREESCALE_EDMA_NBYTES_MLOFFYES_MLOFF() so it works with negative offsets.
author vae
date Wed, 29 Apr 2015 23:31:48 +0000
parents 74dbf4c3f2e1
children
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1 #ifndef CYGONCE_LIBC_STDLIB_DIV_INL
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2 #define CYGONCE_LIBC_STDLIB_DIV_INL
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3 /*===========================================================================
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4 //
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5 // div.inl
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6 //
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7 // Inline implementations for the ISO standard utility functions
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8 // div() and ldiv()
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9 //
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10 //===========================================================================
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11 // ####ECOSGPLCOPYRIGHTBEGIN####
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12 // -------------------------------------------
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13 // This file is part of eCos, the Embedded Configurable Operating System.
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14 // Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
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15 //
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16 // eCos is free software; you can redistribute it and/or modify it under
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17 // the terms of the GNU General Public License as published by the Free
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18 // Software Foundation; either version 2 or (at your option) any later
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19 // version.
208
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20 //
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21 // eCos is distributed in the hope that it will be useful, but WITHOUT
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22 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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23 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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24 // for more details.
208
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25 //
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26 // You should have received a copy of the GNU General Public License
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27 // along with eCos; if not, write to the Free Software Foundation, Inc.,
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28 // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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29 //
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30 // As a special exception, if other files instantiate templates or use
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31 // macros or inline functions from this file, or you compile this file
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32 // and link it with other works to produce a work based on this file,
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33 // this file does not by itself cause the resulting work to be covered by
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34 // the GNU General Public License. However the source code for this file
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35 // must still be made available in accordance with section (3) of the GNU
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36 // General Public License v2.
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37 //
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38 // This exception does not invalidate any other reasons why a work based
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39 // on this file might be covered by the GNU General Public License.
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40 // -------------------------------------------
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41 // ####ECOSGPLCOPYRIGHTEND####
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42 //===========================================================================
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43 //#####DESCRIPTIONBEGIN####
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44 //
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45 // Author(s): jlarmour
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46 // Contributors:
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47 // Date: 2000-04-28
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48 // Purpose:
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49 // Description:
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50 // Usage: Do not include this file directly - include <stdlib.h> instead
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51 //
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52 //####DESCRIPTIONEND####
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53 //
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54 //=========================================================================*/
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55
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56 // CONFIGURATION
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57
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58 #include <pkgconf/libc_stdlib.h> // Configuration header
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59
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60 // INCLUDES
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61
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62 #include <cyg/infra/cyg_ass.h> // Assertion support
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63 #include <cyg/infra/cyg_trac.h> // Tracing support
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64
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65 /* TYPE DEFINITIONS */
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66
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67 /* return type of the div() function */
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68
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69 typedef struct {
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70 int quot; /* quotient */
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71 int rem; /* remainder */
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72 } div_t;
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73
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74
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75 /* return type of the ldiv() function */
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76
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77 typedef struct {
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78 long quot; /* quotient */
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79 long rem; /* remainder */
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80 } ldiv_t;
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81
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82 /* FUNCTION PROTOTYPES */
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83
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84 #ifdef __cplusplus
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85 extern "C" {
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86 #endif
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87
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88 extern div_t
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89 div( int /* numerator */, int /* denominator */ ) __attribute__((__const__));
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90
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91 extern ldiv_t
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92 ldiv( long /* numerator */, long /* denominator */ ) __attribute__((__const__));
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93
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94 #ifdef __cplusplus
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95 } /* extern "C" */
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96 #endif
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97
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98 /* FUNCTIONS */
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99
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100 #ifndef CYGPRI_LIBC_STDLIB_DIV_INLINE
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101 # define CYGPRI_LIBC_STDLIB_DIV_INLINE extern __inline__
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102 #endif
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103
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104 CYGPRI_LIBC_STDLIB_DIV_INLINE div_t
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105 div( int __numer, int __denom )
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106 {
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107 div_t __ret;
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108
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109 CYG_REPORT_FUNCNAMETYPE( "div", "quotient: %d");
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110 CYG_REPORT_FUNCARG2DV( __numer, __denom );
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111 // FIXME: what if they want it handled with SIGFPE? Should have option
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112 CYG_PRECONDITION(__denom != 0, "division by zero attempted!");
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113
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114 __ret.quot = __numer / __denom;
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115 __ret.rem = __numer % __denom;
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116
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117 // But the modulo is implementation-defined for -ve numbers (ISO C 6.3.5)
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118 // and we are required to "round" to zero (ISO C 7.10.6.2)
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119 //
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120 // The cases we have to deal with are inexact division of:
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121 // a) + div +
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122 // b) + div -
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123 // c) - div +
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124 // d) - div -
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125 //
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126 // a) can never go wrong and the quotient and remainder are always positive
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127 // b) only goes wrong if the negative quotient has been "rounded" to
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128 // -infinity - if so then the remainder will be negative when it
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129 // should be positive or zero
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130 // c) only goes wrong if the negative quotient has been "rounded" to
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131 // -infinity - if so then the remainder will be positive when it
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132 // should be negative or zero
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133 // d) only goes wrong if the positive quotient has been rounded to
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134 // +infinity - if so then the remainder will be positive when it
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135 // should be negative or zero
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136 //
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137 // So the correct sign of the remainder corresponds to the sign of the
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138 // numerator. Which means we can say that the result needs adjusting
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139 // iff the sign of the numerator is different from the sign of the
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140 // remainder.
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141 //
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142 // You may be interested to know that the Berkeley version of div()
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143 // would get this wrong for e.g. (c) and (d) on some targets.
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144 // e.g. for (-5)/4 it could leave the result as -2R3
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145
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146 if ((__ret.rem < 0) && (__numer > 0)) {
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147 ++__ret.quot;
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148 __ret.rem -= __denom;
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149 } else if ((__ret.rem > 0) && (__numer < 0)) {
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150 --__ret.quot;
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151 __ret.rem += __denom;
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152 } // else
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153
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154 CYG_REPORT_RETVAL( __ret.quot );
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155
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156 return __ret;
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157 } // div()
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158
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159 CYGPRI_LIBC_STDLIB_DIV_INLINE ldiv_t
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160 ldiv( long __numer, long __denom )
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161 {
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162 ldiv_t __ret;
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163
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164 CYG_REPORT_FUNCNAMETYPE( "ldiv", "quotient: %d");
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165 CYG_REPORT_FUNCARG2DV( __numer, __denom );
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166 // FIXME: what if they want it handled with SIGFPE? Should have option
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167 CYG_PRECONDITION(__denom != 0, "division by zero attempted!");
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168
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169 __ret.quot = __numer / __denom;
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170 __ret.rem = __numer % __denom;
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171
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172 // But the modulo is implementation-defined for -ve numbers (ISO C 6.3.5)
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173 // and we are required to "round" to zero (ISO C 7.10.6.2)
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174 //
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175 // The cases we have to deal with are inexact division of:
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176 // a) + div +
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177 // b) + div -
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178 // c) - div +
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179 // d) - div -
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180 //
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181 // a) can never go wrong and the quotient and remainder are always positive
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182 // b) only goes wrong if the negative quotient has been "rounded" to
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183 // -infinity - if so then the remainder will be negative when it
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184 // should be positive or zero
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185 // c) only goes wrong if the negative quotient has been "rounded" to
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186 // -infinity - if so then the remainder will be positive when it
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187 // should be negative or zero
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188 // d) only goes wrong if the positive quotient has been rounded to
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189 // +infinity - if so then the remainder will be positive when it
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190 // should be negative or zero
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191 //
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192 // So the correct sign of the remainder corresponds to the sign of the
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193 // numerator. Which means we can say that the result needs adjusting
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194 // iff the sign of the numerator is different from the sign of the
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195 // remainder.
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196 //
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197 // You may be interested to know that the Berkeley version of ldiv()
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198 // would get this wrong for e.g. (c) and (d) on some targets.
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199 // e.g. for (-5)/4 it could leave the result as -2R3
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200
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201 if ((__ret.rem < 0) && (__numer > 0)) {
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202 ++__ret.quot;
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203 __ret.rem -= __denom;
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204 } else if ((__ret.rem > 0) && (__numer < 0)) {
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205 --__ret.quot;
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206 __ret.rem += __denom;
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207 } // else
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208
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209 CYG_REPORT_RETVAL( __ret.quot );
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210
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211 return __ret;
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212 } // ldiv()
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213
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214
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215 #endif // CYGONCE_LIBC_STDLIB_DIV_INL multiple inclusion protection
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216
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217 // EOF div.inl