hg/stx-libbasic: comparison LargeInteger.st

equal deleted inserted replaced

-:768802bc61a4
+:3846b94301b8
 __len3 = __len - 3;
 while (__index < __len3) {
 __diff = ((unsigned int *)(__digitP+__index-1))[0] - (__borrow & 0xFFFFFFFFL);
 __borrow >>= 32;
 if (__diff < 0) {
-__diff += 0x100000000;
+/* __diff += 0x100000000; */
 __borrow++;
 }
 ((unsigned int *)(__resultP+__index-1))[0] = __diff;
 __index += 4;
 }
 */
 while (__index < __len) {
 __diff = ((unsigned short *)(__digitP+__index-1))[0] - (__borrow & 0xFFFF);
 __borrow >>= 16;
 if (__diff < 0) {
-__diff += 0x10000;
+/* __diff += 0x10000; */
 __borrow++;
+} else {
+if (__borrow == 0) {
+((unsigned short *)(__resultP+__index-1))[0] = __diff;
+__index += 2;
+/* nothing more to subtract .. */
+while (__index < __len) {
+((unsigned short *)(__resultP+__index-1))[0] = ((unsigned short *)(__digitP+__index-1))[0];
+__index += 2;
+}
+if (__index <= __len) {
+__resultP[__index-1] = __digitP[__index-1];
+}
+break;
+}
 }
 ((unsigned short *)(__resultP+__index-1))[0] = __diff;
 __index += 2;
 }
 #endif
 while (__index <= __len) {
 __diff = __digitP[__index-1] - (__borrow & 0xFF);
 __borrow >>= 8;
 if (__diff < 0) {
-__diff += 0x100;
+/* __diff += 0x100; */
 __borrow++;
+} else {
+if (__borrow == 0) {
+__resultP[__index-1] = __diff;
+__index++;
+/* nothing more to subtract .. */
+while (__index <= __len) {
+__resultP[__index-1] = __digitP[__index-1];
+__index++;
+}
+break;
+}
 }
 __resultP[__index-1] = __diff;
 __index++;
 }
 lastDigit = __MKSMALLINT( __resultP[__index-1-1] );
 - __borrow;
 if (__diff >= 0) {
 __borrow = 0;
 } else {
 __borrow = 1;
-__diff += 0x10000;
+/* __diff += 0x10000; */
 }
 ((unsigned short *)(__resultDigits+__index-1))[0] = __diff;
 __index += 2;
 }
-if (__index <= __minLen) {
+if (__index == __minLen) {
 /* one of the operands has odd length - cannot continue short-wise */
 } else {
 if (__len1 > __len2) {
 while (__index < __len1) {
 __diff = ((unsigned short *)(__myDigits+__index-1))[0] - __borrow;
 if (__diff >= 0) {
 __borrow = 0;
+((unsigned short *)(__resultDigits+__index-1))[0] = __diff;
+__index += 2;
 /* copy over rest */
-__resultDigits[__index-1] = __diff;
-__index += 2;
 while (__index < __len1) {
 ((unsigned short *)(__resultDigits+__index-1))[0] = ((unsigned short *)(__myDigits+__index-1))[0];
 __index+=2;
 }
+if (__index <= __len1) {
+__resultDigits[__index-1] = __myDigits[__index-1];
+__index++;
+}
 break;
 }
 __borrow = 1;
-__diff += 0x10000;
+/* __diff += 0x10000; */
 ((unsigned short *)(__resultDigits+__index-1))[0] = __diff;
 __index += 2;
 }
 } else {
 if (__len2 > __len1) {
 __diff = 0 - ((unsigned short *)(__otherDigits+__index-1))[0] - __borrow;
 if (__diff >= 0) {
 __borrow = 0;
 } else {
 __borrow = 1;
-__diff += 0x10000;
+/* __diff += 0x10000; */
 }
 ((unsigned short *)(__resultDigits+__index-1))[0] = __diff;
 __index += 2;
 }
 }
 __diff = __myDigits[__index-1] - __otherDigits[__index-1] - __borrow;
 if (__diff >= 0) {
 __borrow = 0;
 } else {
 __borrow = 1;
-__diff += 0x100;
+/* __diff += 0x100; */
 }
 __resultDigits[__index-1] = __diff;
 __index++;
 }
 __index++;
 }
 break;
 }
 __borrow = 1;
-__diff += 0x100;
+/* __diff += 0x100; */
 __resultDigits[__index-1] = __diff;
 __index++;
 }
 } else {
 if (__len2 > __len1) {
 __diff = 0 - __otherDigits[__index-1] - __borrow;
 if (__diff >= 0) {
 __borrow = 0;
 } else {
 __borrow = 1;
-__diff += 0x100;
+/* __diff += 0x100; */
 }
 __resultDigits[__index-1] = __diff;
 __index++;
 }
 }
 !
 absSubtract:aLargeInteger
 "private helper for division:
 destructively subtract aLargeInteger from myself
-return true, if the result is non-zero, false otherwise.
+AND return true, if the result is non-zero, false otherwise.
 (i.e. this method has both a return value and a side-effect
 on the receiver)
 Only allowed for positive receiver and argument
 The receiver must be >= the argument.
 The receiver must be a temporary scratch-number"
 - _borrow;
 if (_diff >= 0) {
 _borrow = 0;
 } else {
 _borrow = 1;
-_diff += 0x10000;
+/* _diff += 0x10000; */
 }
 ((unsigned short *)(_myDigits+_index-1))[0] = _diff;
 anyBitNonZero |= (_diff & 0xFFFF);
 _index += 2;
 }
 if (_index <= _len2) {
 /*
 * cannot continue with shorts - there is an odd number of
 * bytes in the minuent
 */
 _index++;
 }
 RETURN (anyBitNonZero ? true : false);
 }
 _borrow = 1;
-_diff += 0x10000;
+/* _diff += 0x10000; */
 ((unsigned short *)(_myDigits+_index-1))[0] = _diff;
 anyBitNonZero |= (_diff & 0xFFFF);
 _index += 2;
 }
 - _borrow;
 if (_diff >= 0) {
 _borrow = 0;
 } else {
 _borrow = 1;
-_diff += 0x100;
+/* _diff += 0x100; */
 }
 _myDigits[_index - 1] = _diff;
 anyBitNonZero |= (_diff & 0xFF);
 _index++;
 }
 _index++;
 }
 break;
 }
 _borrow = 1;
-_diff += 0x100;
+/* _diff += 0x100; */
 _myDigits[_index - 1] = _diff;
 anyBitNonZero |= (_diff & 0xFF);
 _index++;
 }
 ! !
 !LargeInteger class methodsFor:'documentation'!
 version
-^ '$Header: /cvs/stx/stx/libbasic/LargeInteger.st,v 1.112 1999-06-02 10:49:21 cg Exp $'
+^ '$Header: /cvs/stx/stx/libbasic/LargeInteger.st,v 1.113 1999-06-02 12:56:46 cg Exp $'
 ! !

changeset 4254	3846b94301b8
parent 4252	860133fce64f
child 4255	73212f63b6a6