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1 /* This is an assembly language implementation of mulsi3, divsi3, and modsi3
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2 for the sparc processor.
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3
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4 These routines are derived from the SPARC Architecture Manual, version 8,
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5 slightly edited to match the desired calling convention, and also to
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6 optimize them for our purposes. */
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7
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8 #ifdef L_mulsi3
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9 .text
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10 .align 4
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11 .global .umul
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12 .proc 4
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13 .umul:
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14 or %o0, %o1, %o4 ! logical or of multiplier and multiplicand
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15 mov %o0, %y ! multiplier to Y register
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16 andncc %o4, 0xfff, %o5 ! mask out lower 12 bits
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17 be mul_shortway ! can do it the short way
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18 andcc %g0, %g0, %o4 ! zero the partial product and clear NV cc
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19 !
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20 ! long multiply
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21 !
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22 mulscc %o4, %o1, %o4 ! first iteration of 33
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23 mulscc %o4, %o1, %o4
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24 mulscc %o4, %o1, %o4
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25 mulscc %o4, %o1, %o4
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26 mulscc %o4, %o1, %o4
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27 mulscc %o4, %o1, %o4
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28 mulscc %o4, %o1, %o4
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29 mulscc %o4, %o1, %o4
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30 mulscc %o4, %o1, %o4
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31 mulscc %o4, %o1, %o4
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32 mulscc %o4, %o1, %o4
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33 mulscc %o4, %o1, %o4
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34 mulscc %o4, %o1, %o4
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35 mulscc %o4, %o1, %o4
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36 mulscc %o4, %o1, %o4
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37 mulscc %o4, %o1, %o4
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38 mulscc %o4, %o1, %o4
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39 mulscc %o4, %o1, %o4
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40 mulscc %o4, %o1, %o4
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41 mulscc %o4, %o1, %o4
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42 mulscc %o4, %o1, %o4
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43 mulscc %o4, %o1, %o4
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44 mulscc %o4, %o1, %o4
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45 mulscc %o4, %o1, %o4
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46 mulscc %o4, %o1, %o4
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47 mulscc %o4, %o1, %o4
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48 mulscc %o4, %o1, %o4
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49 mulscc %o4, %o1, %o4
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50 mulscc %o4, %o1, %o4
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51 mulscc %o4, %o1, %o4
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52 mulscc %o4, %o1, %o4
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53 mulscc %o4, %o1, %o4 ! 32nd iteration
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54 mulscc %o4, %g0, %o4 ! last iteration only shifts
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55 ! the upper 32 bits of product are wrong, but we do not care
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56 retl
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57 rd %y, %o0
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58 !
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59 ! short multiply
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60 !
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61 mul_shortway:
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62 mulscc %o4, %o1, %o4 ! first iteration of 13
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63 mulscc %o4, %o1, %o4
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64 mulscc %o4, %o1, %o4
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65 mulscc %o4, %o1, %o4
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66 mulscc %o4, %o1, %o4
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67 mulscc %o4, %o1, %o4
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68 mulscc %o4, %o1, %o4
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69 mulscc %o4, %o1, %o4
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70 mulscc %o4, %o1, %o4
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71 mulscc %o4, %o1, %o4
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72 mulscc %o4, %o1, %o4
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73 mulscc %o4, %o1, %o4 ! 12th iteration
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74 mulscc %o4, %g0, %o4 ! last iteration only shifts
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75 rd %y, %o5
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76 sll %o4, 12, %o4 ! left shift partial product by 12 bits
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77 srl %o5, 20, %o5 ! right shift partial product by 20 bits
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78 retl
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79 or %o5, %o4, %o0 ! merge for true product
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80 #endif
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81
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82 #ifdef L_divsi3
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83 /*
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84 * Division and remainder, from Appendix E of the SPARC Version 8
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85 * Architecture Manual, with fixes from Gordon Irlam.
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86 */
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87
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88 /*
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89 * Input: dividend and divisor in %o0 and %o1 respectively.
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90 *
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91 * m4 parameters:
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92 * .div name of function to generate
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93 * div div=div => %o0 / %o1; div=rem => %o0 % %o1
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94 * true true=true => signed; true=false => unsigned
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95 *
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96 * Algorithm parameters:
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97 * N how many bits per iteration we try to get (4)
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98 * WORDSIZE total number of bits (32)
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99 *
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100 * Derived constants:
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101 * TOPBITS number of bits in the top decade of a number
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102 *
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103 * Important variables:
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104 * Q the partial quotient under development (initially 0)
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105 * R the remainder so far, initially the dividend
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106 * ITER number of main division loop iterations required;
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107 * equal to ceil(log2(quotient) / N). Note that this
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108 * is the log base (2^N) of the quotient.
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109 * V the current comparand, initially divisor*2^(ITER*N-1)
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110 *
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111 * Cost:
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112 * Current estimate for non-large dividend is
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113 * ceil(log2(quotient) / N) * (10 + 7N/2) + C
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114 * A large dividend is one greater than 2^(31-TOPBITS) and takes a
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115 * different path, as the upper bits of the quotient must be developed
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116 * one bit at a time.
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117 */
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118 .global .udiv
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119 .align 4
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120 .proc 4
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121 .text
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122 .udiv:
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123 b ready_to_divide
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124 mov 0, %g3 ! result is always positive
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125
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126 .global .div
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127 .align 4
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128 .proc 4
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129 .text
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130 .div:
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131 ! compute sign of result; if neither is negative, no problem
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132 orcc %o1, %o0, %g0 ! either negative?
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133 bge ready_to_divide ! no, go do the divide
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134 xor %o1, %o0, %g3 ! compute sign in any case
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135 tst %o1
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136 bge 1f
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137 tst %o0
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138 ! %o1 is definitely negative; %o0 might also be negative
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139 bge ready_to_divide ! if %o0 not negative...
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140 sub %g0, %o1, %o1 ! in any case, make %o1 nonneg
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141 1: ! %o0 is negative, %o1 is nonnegative
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142 sub %g0, %o0, %o0 ! make %o0 nonnegative
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143
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144
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145 ready_to_divide:
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146
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147 ! Ready to divide. Compute size of quotient; scale comparand.
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148 orcc %o1, %g0, %o5
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149 bne 1f
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150 mov %o0, %o3
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151
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152 ! Divide by zero trap. If it returns, return 0 (about as
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153 ! wrong as possible, but that is what SunOS does...).
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154 ta 0x2 ! ST_DIV0
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155 retl
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156 clr %o0
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157
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158 1:
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159 cmp %o3, %o5 ! if %o1 exceeds %o0, done
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160 blu got_result ! (and algorithm fails otherwise)
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161 clr %o2
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162 sethi %hi(1 << (32 - 4 - 1)), %g1
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163 cmp %o3, %g1
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164 blu not_really_big
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165 clr %o4
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166
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167 ! Here the dividend is >= 2**(31-N) or so. We must be careful here,
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168 ! as our usual N-at-a-shot divide step will cause overflow and havoc.
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169 ! The number of bits in the result here is N*ITER+SC, where SC <= N.
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170 ! Compute ITER in an unorthodox manner: know we need to shift V into
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171 ! the top decade: so do not even bother to compare to R.
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172 1:
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173 cmp %o5, %g1
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174 bgeu 3f
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175 mov 1, %g2
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176 sll %o5, 4, %o5
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177 b 1b
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178 add %o4, 1, %o4
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179
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180 ! Now compute %g2.
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181 2: addcc %o5, %o5, %o5
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182 bcc not_too_big
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183 add %g2, 1, %g2
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184
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185 ! We get here if the %o1 overflowed while shifting.
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186 ! This means that %o3 has the high-order bit set.
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187 ! Restore %o5 and subtract from %o3.
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188 sll %g1, 4, %g1 ! high order bit
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189 srl %o5, 1, %o5 ! rest of %o5
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190 add %o5, %g1, %o5
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191 b do_single_div
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192 sub %g2, 1, %g2
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193
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194 not_too_big:
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195 3: cmp %o5, %o3
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196 blu 2b
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197 nop
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198 be do_single_div
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199 nop
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200 /* NB: these are commented out in the V8-SPARC manual as well */
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201 /* (I do not understand this) */
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202 ! %o5 > %o3: went too far: back up 1 step
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203 ! srl %o5, 1, %o5
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204 ! dec %g2
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205 ! do single-bit divide steps
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206 !
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207 ! We have to be careful here. We know that %o3 >= %o5, so we can do the
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208 ! first divide step without thinking. BUT, the others are conditional,
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209 ! and are only done if %o3 >= 0. Because both %o3 and %o5 may have the high-
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210 ! order bit set in the first step, just falling into the regular
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211 ! division loop will mess up the first time around.
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212 ! So we unroll slightly...
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213 do_single_div:
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214 subcc %g2, 1, %g2
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215 bl end_regular_divide
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216 nop
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217 sub %o3, %o5, %o3
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218 mov 1, %o2
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219 b end_single_divloop
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220 nop
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221 single_divloop:
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222 sll %o2, 1, %o2
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223 bl 1f
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224 srl %o5, 1, %o5
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225 ! %o3 >= 0
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226 sub %o3, %o5, %o3
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227 b 2f
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228 add %o2, 1, %o2
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229 1: ! %o3 < 0
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230 add %o3, %o5, %o3
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231 sub %o2, 1, %o2
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232 2:
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233 end_single_divloop:
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234 subcc %g2, 1, %g2
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235 bge single_divloop
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236 tst %o3
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237 b,a end_regular_divide
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238
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239 not_really_big:
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240 1:
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241 sll %o5, 4, %o5
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242 cmp %o5, %o3
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243 bleu 1b
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244 addcc %o4, 1, %o4
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245 be got_result
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246 sub %o4, 1, %o4
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247
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248 tst %o3 ! set up for initial iteration
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249 divloop:
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250 sll %o2, 4, %o2
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251 ! depth 1, accumulated bits 0
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252 bl L1.16
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253 srl %o5,1,%o5
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254 ! remainder is positive
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255 subcc %o3,%o5,%o3
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256 ! depth 2, accumulated bits 1
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257 bl L2.17
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258 srl %o5,1,%o5
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259 ! remainder is positive
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260 subcc %o3,%o5,%o3
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261 ! depth 3, accumulated bits 3
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262 bl L3.19
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263 srl %o5,1,%o5
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264 ! remainder is positive
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265 subcc %o3,%o5,%o3
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266 ! depth 4, accumulated bits 7
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267 bl L4.23
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268 srl %o5,1,%o5
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269 ! remainder is positive
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270 subcc %o3,%o5,%o3
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271 b 9f
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272 add %o2, (7*2+1), %o2
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273
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274 L4.23:
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275 ! remainder is negative
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276 addcc %o3,%o5,%o3
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277 b 9f
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278 add %o2, (7*2-1), %o2
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279
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280
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281 L3.19:
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282 ! remainder is negative
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283 addcc %o3,%o5,%o3
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284 ! depth 4, accumulated bits 5
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285 bl L4.21
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286 srl %o5,1,%o5
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287 ! remainder is positive
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288 subcc %o3,%o5,%o3
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289 b 9f
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290 add %o2, (5*2+1), %o2
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291
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292 L4.21:
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293 ! remainder is negative
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294 addcc %o3,%o5,%o3
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295 b 9f
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296 add %o2, (5*2-1), %o2
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297
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298 L2.17:
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299 ! remainder is negative
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300 addcc %o3,%o5,%o3
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301 ! depth 3, accumulated bits 1
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302 bl L3.17
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303 srl %o5,1,%o5
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304 ! remainder is positive
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305 subcc %o3,%o5,%o3
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306 ! depth 4, accumulated bits 3
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307 bl L4.19
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308 srl %o5,1,%o5
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309 ! remainder is positive
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310 subcc %o3,%o5,%o3
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311 b 9f
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312 add %o2, (3*2+1), %o2
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313
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314 L4.19:
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315 ! remainder is negative
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316 addcc %o3,%o5,%o3
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317 b 9f
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318 add %o2, (3*2-1), %o2
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319
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320 L3.17:
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321 ! remainder is negative
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322 addcc %o3,%o5,%o3
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323 ! depth 4, accumulated bits 1
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324 bl L4.17
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325 srl %o5,1,%o5
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326 ! remainder is positive
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327 subcc %o3,%o5,%o3
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328 b 9f
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329 add %o2, (1*2+1), %o2
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330
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331 L4.17:
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332 ! remainder is negative
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333 addcc %o3,%o5,%o3
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334 b 9f
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335 add %o2, (1*2-1), %o2
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336
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337 L1.16:
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338 ! remainder is negative
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339 addcc %o3,%o5,%o3
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340 ! depth 2, accumulated bits -1
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341 bl L2.15
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342 srl %o5,1,%o5
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343 ! remainder is positive
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344 subcc %o3,%o5,%o3
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345 ! depth 3, accumulated bits -1
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346 bl L3.15
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347 srl %o5,1,%o5
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348 ! remainder is positive
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349 subcc %o3,%o5,%o3
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350 ! depth 4, accumulated bits -1
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351 bl L4.15
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352 srl %o5,1,%o5
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353 ! remainder is positive
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354 subcc %o3,%o5,%o3
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355 b 9f
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356 add %o2, (-1*2+1), %o2
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357
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358 L4.15:
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359 ! remainder is negative
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360 addcc %o3,%o5,%o3
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361 b 9f
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362 add %o2, (-1*2-1), %o2
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363
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364 L3.15:
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365 ! remainder is negative
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366 addcc %o3,%o5,%o3
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367 ! depth 4, accumulated bits -3
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368 bl L4.13
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369 srl %o5,1,%o5
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370 ! remainder is positive
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371 subcc %o3,%o5,%o3
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372 b 9f
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373 add %o2, (-3*2+1), %o2
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374
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375 L4.13:
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376 ! remainder is negative
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377 addcc %o3,%o5,%o3
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378 b 9f
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379 add %o2, (-3*2-1), %o2
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380
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381 L2.15:
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382 ! remainder is negative
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383 addcc %o3,%o5,%o3
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384 ! depth 3, accumulated bits -3
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385 bl L3.13
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386 srl %o5,1,%o5
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387 ! remainder is positive
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388 subcc %o3,%o5,%o3
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389 ! depth 4, accumulated bits -5
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390 bl L4.11
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391 srl %o5,1,%o5
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392 ! remainder is positive
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393 subcc %o3,%o5,%o3
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394 b 9f
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395 add %o2, (-5*2+1), %o2
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396
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397 L4.11:
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398 ! remainder is negative
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399 addcc %o3,%o5,%o3
|
|
|
400 b 9f
|
|
|
401 add %o2, (-5*2-1), %o2
|
|
|
402
|
|
|
403 L3.13:
|
|
|
404 ! remainder is negative
|
|
|
405 addcc %o3,%o5,%o3
|
|
|
406 ! depth 4, accumulated bits -7
|
|
|
407 bl L4.9
|
|
|
408 srl %o5,1,%o5
|
|
|
409 ! remainder is positive
|
|
|
410 subcc %o3,%o5,%o3
|
|
|
411 b 9f
|
|
|
412 add %o2, (-7*2+1), %o2
|
|
|
413
|
|
|
414 L4.9:
|
|
|
415 ! remainder is negative
|
|
|
416 addcc %o3,%o5,%o3
|
|
|
417 b 9f
|
|
|
418 add %o2, (-7*2-1), %o2
|
|
|
419
|
|
|
420 9:
|
|
|
421 end_regular_divide:
|
|
|
422 subcc %o4, 1, %o4
|
|
|
423 bge divloop
|
|
|
424 tst %o3
|
|
|
425 bl,a got_result
|
|
|
426 ! non-restoring fixup here (one instruction only!)
|
|
|
427 sub %o2, 1, %o2
|
|
|
428
|
|
|
429
|
|
|
430 got_result:
|
|
|
431 ! check to see if answer should be < 0
|
|
|
432 tst %g3
|
|
|
433 bl,a 1f
|
|
|
434 sub %g0, %o2, %o2
|
|
|
435 1:
|
|
|
436 retl
|
|
|
437 mov %o2, %o0
|
|
|
438 #endif
|
|
|
439
|
|
|
440 #ifdef L_modsi3
|
|
|
441 /* This implementation was taken from glibc:
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|
|
442 *
|
|
|
443 * Input: dividend and divisor in %o0 and %o1 respectively.
|
|
|
444 *
|
|
|
445 * Algorithm parameters:
|
|
|
446 * N how many bits per iteration we try to get (4)
|
|
|
447 * WORDSIZE total number of bits (32)
|
|
|
448 *
|
|
|
449 * Derived constants:
|
|
|
450 * TOPBITS number of bits in the top decade of a number
|
|
|
451 *
|
|
|
452 * Important variables:
|
|
|
453 * Q the partial quotient under development (initially 0)
|
|
|
454 * R the remainder so far, initially the dividend
|
|
|
455 * ITER number of main division loop iterations required;
|
|
|
456 * equal to ceil(log2(quotient) / N). Note that this
|
|
|
457 * is the log base (2^N) of the quotient.
|
|
|
458 * V the current comparand, initially divisor*2^(ITER*N-1)
|
|
|
459 *
|
|
|
460 * Cost:
|
|
|
461 * Current estimate for non-large dividend is
|
|
|
462 * ceil(log2(quotient) / N) * (10 + 7N/2) + C
|
|
|
463 * A large dividend is one greater than 2^(31-TOPBITS) and takes a
|
|
|
464 * different path, as the upper bits of the quotient must be developed
|
|
|
465 * one bit at a time.
|
|
|
466 */
|
|
|
467 .text
|
|
|
468 .align 4
|
|
|
469 .global .urem
|
|
|
470 .proc 4
|
|
|
471 .urem:
|
|
|
472 b divide
|
|
|
473 mov 0, %g3 ! result always positive
|
|
|
474
|
|
|
475 .align 4
|
|
|
476 .global .rem
|
|
|
477 .proc 4
|
|
|
478 .rem:
|
|
|
479 ! compute sign of result; if neither is negative, no problem
|
|
|
480 orcc %o1, %o0, %g0 ! either negative?
|
|
|
481 bge 2f ! no, go do the divide
|
|
|
482 mov %o0, %g3 ! sign of remainder matches %o0
|
|
|
483 tst %o1
|
|
|
484 bge 1f
|
|
|
485 tst %o0
|
|
|
486 ! %o1 is definitely negative; %o0 might also be negative
|
|
|
487 bge 2f ! if %o0 not negative...
|
|
|
488 sub %g0, %o1, %o1 ! in any case, make %o1 nonneg
|
|
|
489 1: ! %o0 is negative, %o1 is nonnegative
|
|
|
490 sub %g0, %o0, %o0 ! make %o0 nonnegative
|
|
|
491 2:
|
|
|
492
|
|
|
493 ! Ready to divide. Compute size of quotient; scale comparand.
|
|
|
494 divide:
|
|
|
495 orcc %o1, %g0, %o5
|
|
|
496 bne 1f
|
|
|
497 mov %o0, %o3
|
|
|
498
|
|
|
499 ! Divide by zero trap. If it returns, return 0 (about as
|
|
|
500 ! wrong as possible, but that is what SunOS does...).
|
|
|
501 ta 0x2 !ST_DIV0
|
|
|
502 retl
|
|
|
503 clr %o0
|
|
|
504
|
|
|
505 1:
|
|
|
506 cmp %o3, %o5 ! if %o1 exceeds %o0, done
|
|
|
507 blu got_result ! (and algorithm fails otherwise)
|
|
|
508 clr %o2
|
|
|
509 sethi %hi(1 << (32 - 4 - 1)), %g1
|
|
|
510 cmp %o3, %g1
|
|
|
511 blu not_really_big
|
|
|
512 clr %o4
|
|
|
513
|
|
|
514 ! Here the dividend is >= 2**(31-N) or so. We must be careful here,
|
|
|
515 ! as our usual N-at-a-shot divide step will cause overflow and havoc.
|
|
|
516 ! The number of bits in the result here is N*ITER+SC, where SC <= N.
|
|
|
517 ! Compute ITER in an unorthodox manner: know we need to shift V into
|
|
|
518 ! the top decade: so do not even bother to compare to R.
|
|
|
519 1:
|
|
|
520 cmp %o5, %g1
|
|
|
521 bgeu 3f
|
|
|
522 mov 1, %g2
|
|
|
523 sll %o5, 4, %o5
|
|
|
524 b 1b
|
|
|
525 add %o4, 1, %o4
|
|
|
526
|
|
|
527 ! Now compute %g2.
|
|
|
528 2: addcc %o5, %o5, %o5
|
|
|
529 bcc not_too_big
|
|
|
530 add %g2, 1, %g2
|
|
|
531
|
|
|
532 ! We get here if the %o1 overflowed while shifting.
|
|
|
533 ! This means that %o3 has the high-order bit set.
|
|
|
534 ! Restore %o5 and subtract from %o3.
|
|
|
535 sll %g1, 4, %g1 ! high order bit
|
|
|
536 srl %o5, 1, %o5 ! rest of %o5
|
|
|
537 add %o5, %g1, %o5
|
|
|
538 b do_single_div
|
|
|
539 sub %g2, 1, %g2
|
|
|
540
|
|
|
541 not_too_big:
|
|
|
542 3: cmp %o5, %o3
|
|
|
543 blu 2b
|
|
|
544 nop
|
|
|
545 be do_single_div
|
|
|
546 nop
|
|
|
547 /* NB: these are commented out in the V8-SPARC manual as well */
|
|
|
548 /* (I do not understand this) */
|
|
|
549 ! %o5 > %o3: went too far: back up 1 step
|
|
|
550 ! srl %o5, 1, %o5
|
|
|
551 ! dec %g2
|
|
|
552 ! do single-bit divide steps
|
|
|
553 !
|
|
|
554 ! We have to be careful here. We know that %o3 >= %o5, so we can do the
|
|
|
555 ! first divide step without thinking. BUT, the others are conditional,
|
|
|
556 ! and are only done if %o3 >= 0. Because both %o3 and %o5 may have the high-
|
|
|
557 ! order bit set in the first step, just falling into the regular
|
|
|
558 ! division loop will mess up the first time around.
|
|
|
559 ! So we unroll slightly...
|
|
|
560 do_single_div:
|
|
|
561 subcc %g2, 1, %g2
|
|
|
562 bl end_regular_divide
|
|
|
563 nop
|
|
|
564 sub %o3, %o5, %o3
|
|
|
565 mov 1, %o2
|
|
|
566 b end_single_divloop
|
|
|
567 nop
|
|
|
568 single_divloop:
|
|
|
569 sll %o2, 1, %o2
|
|
|
570 bl 1f
|
|
|
571 srl %o5, 1, %o5
|
|
|
572 ! %o3 >= 0
|
|
|
573 sub %o3, %o5, %o3
|
|
|
574 b 2f
|
|
|
575 add %o2, 1, %o2
|
|
|
576 1: ! %o3 < 0
|
|
|
577 add %o3, %o5, %o3
|
|
|
578 sub %o2, 1, %o2
|
|
|
579 2:
|
|
|
580 end_single_divloop:
|
|
|
581 subcc %g2, 1, %g2
|
|
|
582 bge single_divloop
|
|
|
583 tst %o3
|
|
|
584 b,a end_regular_divide
|
|
|
585
|
|
|
586 not_really_big:
|
|
|
587 1:
|
|
|
588 sll %o5, 4, %o5
|
|
|
589 cmp %o5, %o3
|
|
|
590 bleu 1b
|
|
|
591 addcc %o4, 1, %o4
|
|
|
592 be got_result
|
|
|
593 sub %o4, 1, %o4
|
|
|
594
|
|
|
595 tst %o3 ! set up for initial iteration
|
|
|
596 divloop:
|
|
|
597 sll %o2, 4, %o2
|
|
|
598 ! depth 1, accumulated bits 0
|
|
|
599 bl L1.16
|
|
|
600 srl %o5,1,%o5
|
|
|
601 ! remainder is positive
|
|
|
602 subcc %o3,%o5,%o3
|
|
|
603 ! depth 2, accumulated bits 1
|
|
|
604 bl L2.17
|
|
|
605 srl %o5,1,%o5
|
|
|
606 ! remainder is positive
|
|
|
607 subcc %o3,%o5,%o3
|
|
|
608 ! depth 3, accumulated bits 3
|
|
|
609 bl L3.19
|
|
|
610 srl %o5,1,%o5
|
|
|
611 ! remainder is positive
|
|
|
612 subcc %o3,%o5,%o3
|
|
|
613 ! depth 4, accumulated bits 7
|
|
|
614 bl L4.23
|
|
|
615 srl %o5,1,%o5
|
|
|
616 ! remainder is positive
|
|
|
617 subcc %o3,%o5,%o3
|
|
|
618 b 9f
|
|
|
619 add %o2, (7*2+1), %o2
|
|
|
620 L4.23:
|
|
|
621 ! remainder is negative
|
|
|
622 addcc %o3,%o5,%o3
|
|
|
623 b 9f
|
|
|
624 add %o2, (7*2-1), %o2
|
|
|
625
|
|
|
626 L3.19:
|
|
|
627 ! remainder is negative
|
|
|
628 addcc %o3,%o5,%o3
|
|
|
629 ! depth 4, accumulated bits 5
|
|
|
630 bl L4.21
|
|
|
631 srl %o5,1,%o5
|
|
|
632 ! remainder is positive
|
|
|
633 subcc %o3,%o5,%o3
|
|
|
634 b 9f
|
|
|
635 add %o2, (5*2+1), %o2
|
|
|
636
|
|
|
637 L4.21:
|
|
|
638 ! remainder is negative
|
|
|
639 addcc %o3,%o5,%o3
|
|
|
640 b 9f
|
|
|
641 add %o2, (5*2-1), %o2
|
|
|
642
|
|
|
643 L2.17:
|
|
|
644 ! remainder is negative
|
|
|
645 addcc %o3,%o5,%o3
|
|
|
646 ! depth 3, accumulated bits 1
|
|
|
647 bl L3.17
|
|
|
648 srl %o5,1,%o5
|
|
|
649 ! remainder is positive
|
|
|
650 subcc %o3,%o5,%o3
|
|
|
651 ! depth 4, accumulated bits 3
|
|
|
652 bl L4.19
|
|
|
653 srl %o5,1,%o5
|
|
|
654 ! remainder is positive
|
|
|
655 subcc %o3,%o5,%o3
|
|
|
656 b 9f
|
|
|
657 add %o2, (3*2+1), %o2
|
|
|
658
|
|
|
659 L4.19:
|
|
|
660 ! remainder is negative
|
|
|
661 addcc %o3,%o5,%o3
|
|
|
662 b 9f
|
|
|
663 add %o2, (3*2-1), %o2
|
|
|
664
|
|
|
665 L3.17:
|
|
|
666 ! remainder is negative
|
|
|
667 addcc %o3,%o5,%o3
|
|
|
668 ! depth 4, accumulated bits 1
|
|
|
669 bl L4.17
|
|
|
670 srl %o5,1,%o5
|
|
|
671 ! remainder is positive
|
|
|
672 subcc %o3,%o5,%o3
|
|
|
673 b 9f
|
|
|
674 add %o2, (1*2+1), %o2
|
|
|
675
|
|
|
676 L4.17:
|
|
|
677 ! remainder is negative
|
|
|
678 addcc %o3,%o5,%o3
|
|
|
679 b 9f
|
|
|
680 add %o2, (1*2-1), %o2
|
|
|
681
|
|
|
682 L1.16:
|
|
|
683 ! remainder is negative
|
|
|
684 addcc %o3,%o5,%o3
|
|
|
685 ! depth 2, accumulated bits -1
|
|
|
686 bl L2.15
|
|
|
687 srl %o5,1,%o5
|
|
|
688 ! remainder is positive
|
|
|
689 subcc %o3,%o5,%o3
|
|
|
690 ! depth 3, accumulated bits -1
|
|
|
691 bl L3.15
|
|
|
692 srl %o5,1,%o5
|
|
|
693 ! remainder is positive
|
|
|
694 subcc %o3,%o5,%o3
|
|
|
695 ! depth 4, accumulated bits -1
|
|
|
696 bl L4.15
|
|
|
697 srl %o5,1,%o5
|
|
|
698 ! remainder is positive
|
|
|
699 subcc %o3,%o5,%o3
|
|
|
700 b 9f
|
|
|
701 add %o2, (-1*2+1), %o2
|
|
|
702
|
|
|
703 L4.15:
|
|
|
704 ! remainder is negative
|
|
|
705 addcc %o3,%o5,%o3
|
|
|
706 b 9f
|
|
|
707 add %o2, (-1*2-1), %o2
|
|
|
708
|
|
|
709 L3.15:
|
|
|
710 ! remainder is negative
|
|
|
711 addcc %o3,%o5,%o3
|
|
|
712 ! depth 4, accumulated bits -3
|
|
|
713 bl L4.13
|
|
|
714 srl %o5,1,%o5
|
|
|
715 ! remainder is positive
|
|
|
716 subcc %o3,%o5,%o3
|
|
|
717 b 9f
|
|
|
718 add %o2, (-3*2+1), %o2
|
|
|
719
|
|
|
720 L4.13:
|
|
|
721 ! remainder is negative
|
|
|
722 addcc %o3,%o5,%o3
|
|
|
723 b 9f
|
|
|
724 add %o2, (-3*2-1), %o2
|
|
|
725
|
|
|
726 L2.15:
|
|
|
727 ! remainder is negative
|
|
|
728 addcc %o3,%o5,%o3
|
|
|
729 ! depth 3, accumulated bits -3
|
|
|
730 bl L3.13
|
|
|
731 srl %o5,1,%o5
|
|
|
732 ! remainder is positive
|
|
|
733 subcc %o3,%o5,%o3
|
|
|
734 ! depth 4, accumulated bits -5
|
|
|
735 bl L4.11
|
|
|
736 srl %o5,1,%o5
|
|
|
737 ! remainder is positive
|
|
|
738 subcc %o3,%o5,%o3
|
|
|
739 b 9f
|
|
|
740 add %o2, (-5*2+1), %o2
|
|
|
741
|
|
|
742 L4.11:
|
|
|
743 ! remainder is negative
|
|
|
744 addcc %o3,%o5,%o3
|
|
|
745 b 9f
|
|
|
746 add %o2, (-5*2-1), %o2
|
|
|
747
|
|
|
748 L3.13:
|
|
|
749 ! remainder is negative
|
|
|
750 addcc %o3,%o5,%o3
|
|
|
751 ! depth 4, accumulated bits -7
|
|
|
752 bl L4.9
|
|
|
753 srl %o5,1,%o5
|
|
|
754 ! remainder is positive
|
|
|
755 subcc %o3,%o5,%o3
|
|
|
756 b 9f
|
|
|
757 add %o2, (-7*2+1), %o2
|
|
|
758
|
|
|
759 L4.9:
|
|
|
760 ! remainder is negative
|
|
|
761 addcc %o3,%o5,%o3
|
|
|
762 b 9f
|
|
|
763 add %o2, (-7*2-1), %o2
|
|
|
764
|
|
|
765 9:
|
|
|
766 end_regular_divide:
|
|
|
767 subcc %o4, 1, %o4
|
|
|
768 bge divloop
|
|
|
769 tst %o3
|
|
|
770 bl,a got_result
|
|
|
771 ! non-restoring fixup here (one instruction only!)
|
|
|
772 add %o3, %o1, %o3
|
|
|
773
|
|
|
774 got_result:
|
|
|
775 ! check to see if answer should be < 0
|
|
|
776 tst %g3
|
|
|
777 bl,a 1f
|
|
|
778 sub %g0, %o3, %o3
|
|
|
779 1:
|
|
|
780 retl
|
|
|
781 mov %o3, %o0
|
|
|
782
|
|
|
783 #endif
|
|
|
784
|
