Page 276 - ARM 64 Bit Assembly Language

Non-integral mathematics 265

55 {
56 if(negative)
57 value = -value;
58 return value << frac_bits;
59 }
60 ++point;
61 /* convert the remaining part into an unpacked BCD number. */
62 for(i=(MAX_DECIMAL_DIGITS-1);i>=0;i--)
63 {
64 if(*point == 0)
65 digits[i] = 0;
66 else
67 {
68 digits[i] = *point - ’0’;
69 ++point;
70 }
71 }
72 /* convert the unpacked BCD number into binary */
73 while(frac_bits > 0)
74 {
75 value <<= 1;
76 if(base10double(digits))
77 value |= 1;
78 frac_bits--;
79 }
80 /* negate if there was a leading ’-’ */
81 if(negative)
82 value = -value;
83 return value;
84 }
85
86 // Round a packed BCD fraction
87 int roundit(int *digits, int current)
88 {
89 while(current > 0)
90 {
91 if(digits[current] > 9)
92 {
93 digits[current] %= 10;
94 digits[current-1]++;
95 }
96 current--;
97 }
98 if((current == 0)&&(digits[current] > 9))
99 {
100 digits[current] %= 10;
101 return 1;
102 }
103 return 0;