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comparison liboctave/oct-inttypes.h @ 13734:28ddb3150943

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Rename signbit to __signbit, until the problem is fixed in gnulib. * oct-inttypes.h (octave_int_arith_base<T, true>): Rename signbit to __signbit to avoid problems with gnulib macro.
author Michael Goffioul <michael.goffioul@gmail.com>
date Thu, 20 Oct 2011 12:54:58 +0100
parents 15eefbd9d4e8
children 72c96de7a403
comparison
equal deleted inserted replaced
13733:b1186adb567e 13734:28ddb3150943
450 typedef typename query_integer_type<sizeof (T), false>::type UT; 450 typedef typename query_integer_type<sizeof (T), false>::type UT;
451 public: 451 public:
452 452
453 // Returns 1 for negative number, 0 otherwise. 453 // Returns 1 for negative number, 0 otherwise.
454 static T 454 static T
455 signbit (T x) 455 __signbit (T x)
456 { 456 {
457 #ifdef HAVE_FAST_INT_OPS 457 #ifdef HAVE_FAST_INT_OPS
458 return static_cast<UT> (x) >> std::numeric_limits<T>::digits; 458 return static_cast<UT> (x) >> std::numeric_limits<T>::digits;
459 #else 459 #else
460 return (x < 0) ? 1 : 0; 460 return (x < 0) ? 1 : 0;
494 494
495 static T 495 static T
496 signum (T x) 496 signum (T x)
497 { 497 {
498 // With modest optimizations, this will compile without a jump. 498 // With modest optimizations, this will compile without a jump.
499 return ((x > 0) ? 1 : 0) - signbit (x); 499 return ((x > 0) ? 1 : 0) - __signbit (x);
500 } 500 }
501 501
502 // FIXME -- we do not have an authority what signed shifts should 502 // FIXME -- we do not have an authority what signed shifts should
503 // exactly do, so we define them the easy way. Note that Matlab does 503 // exactly do, so we define them the easy way. Note that Matlab does
504 // not define signed shifts. 504 // not define signed shifts.
542 // actually return int. 542 // actually return int.
543 T u = static_cast<UT> (x) + static_cast<UT> (y); 543 T u = static_cast<UT> (x) + static_cast<UT> (y);
544 T ux = u ^ x, uy = u ^ y; 544 T ux = u ^ x, uy = u ^ y;
545 if ((ux & uy) < 0) 545 if ((ux & uy) < 0)
546 { 546 {
547 u = octave_int_base<T>::max_val () + signbit (~u); 547 u = octave_int_base<T>::max_val () + __signbit (~u);
548 } 548 }
549 return u; 549 return u;
550 #else 550 #else
551 // We shall carefully avoid anything that may overflow. 551 // We shall carefully avoid anything that may overflow.
552 T u; 552 T u;
583 // actually return int. 583 // actually return int.
584 T u = static_cast<UT> (x) - static_cast<UT> (y); 584 T u = static_cast<UT> (x) - static_cast<UT> (y);
585 T ux = u ^ x, uy = u ^ ~y; 585 T ux = u ^ x, uy = u ^ ~y;
586 if ((ux & uy) < 0) 586 if ((ux & uy) < 0)
587 { 587 {
588 u = octave_int_base<T>::max_val () + signbit (~u); 588 u = octave_int_base<T>::max_val () + __signbit (~u);
589 } 589 }
590 return u; 590 return u;
591 #else 591 #else
592 // We shall carefully avoid anything that may overflow. 592 // We shall carefully avoid anything that may overflow.
593 T u; 593 T u;
649 else 649 else
650 { 650 {
651 z = x / y; 651 z = x / y;
652 T w = -octave_int_abs (x % y); // Can't overflow, but std::abs (x) can! 652 T w = -octave_int_abs (x % y); // Can't overflow, but std::abs (x) can!
653 if (w <= y - w) 653 if (w <= y - w)
654 z -= 1 - (signbit (x) << 1); 654 z -= 1 - (__signbit (x) << 1);
655 } 655 }
656 } 656 }
657 else 657 else
658 { 658 {
659 z = x / y; 659 z = x / y;
661 // std::abs (int64_t). The call to octave_int_abs can't 661 // std::abs (int64_t). The call to octave_int_abs can't
662 // overflow, but std::abs (x) can! 662 // overflow, but std::abs (x) can!
663 T w = octave_int_abs (x % y); 663 T w = octave_int_abs (x % y);
664 664
665 if (w >= y - w) 665 if (w >= y - w)
666 z += 1 - (signbit (x) << 1); 666 z += 1 - (__signbit (x) << 1);
667 } 667 }
668 return z; 668 return z;
669 } 669 }
670 670
671 // Remainder. 671 // Remainder.