//===-- divsi3_impl.h -----------------------------------------------------===//
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//===----------------------------------------------------------------------===//

#ifndef _COLOSSUS_DIVSI3_IMPL_H
#define _COLOSSUS_DIVSI3_IMPL_H

#ifndef TARGET
#error "TARGET not defined"
#endif

#include "../int_lib.h"

__attribute__((target(TARGET)))
static inline si_int divsi3_impl(si_int a, si_int b) {
  const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1;
  si_int s_a = a >> bits_in_word_m1; // s_a = a < 0 ? -1 : 0
  si_int s_b = b >> bits_in_word_m1; // s_b = b < 0 ? -1 : 0

  su_int a_u = (su_int)(a ^ s_a) + (-s_a); // negate if s_a == -1
  su_int b_u = (su_int)(b ^ s_b) + (-s_b); // negate if s_b == -1
  s_a ^= s_b;                        // sign of quotient
  //
  // On CPUs without unsigned hardware division support,
  //  this calls __udivsi3 (notice the cast to su_int).
  // On CPUs with unsigned hardware division support,
  //  this uses the unsigned division instruction.
  //
  return (a_u / b_u ^ s_a) + (-s_a); // negate if s_a == -1
}

#endif // _COLOSSUS_DIVSI3_IMPL_H