/* This has so very few changes over libgcc2's __udivmoddi4 it isn't funny. */ #include <math-emu/soft-fp.h> #undef count_leading_zeros #define count_leading_zeros __FP_CLZ void _fp_udivmodti4(_FP_W_TYPE q[2], _FP_W_TYPE r[2], _FP_W_TYPE n1, _FP_W_TYPE n0, _FP_W_TYPE d1, _FP_W_TYPE d0) { _FP_W_TYPE q0, q1, r0, r1; _FP_I_TYPE b, bm; if (d1 == 0) { #if !UDIV_NEEDS_NORMALIZATION if (d0 > n1) { /* 0q = nn / 0D */ udiv_qrnnd (q0, n0, n1, n0, d0); q1 = 0; /* Remainder in n0. */ } else { /* qq = NN / 0d */ if (d0 == 0) d0 = 1 / d0; /* Divide intentionally by zero. */ udiv_qrnnd (q1, n1, 0, n1, d0); udiv_qrnnd (q0, n0, n1, n0, d0); /* Remainder in n0. */ } r0 = n0; r1 = 0; #else /* UDIV_NEEDS_NORMALIZATION */ if (d0 > n1) { /* 0q = nn / 0D */ count_leading_zeros (bm, d0); if (bm != 0) { /* Normalize, i.e. make the most significant bit of the denominator set. */ d0 = d0 << bm; n1 = (n1 << bm) | (n0 >> (_FP_W_TYPE_SIZE - bm)); n0 = n0 << bm; } udiv_qrnnd (q0, n0, n1, n0, d0); q1 = 0; /* Remainder in n0 >> bm. */ } else { /* qq = NN / 0d */ if (d0 == 0) d0 = 1 / d0; /* Divide intentionally by zero. */ count_leading_zeros (bm, d0); if (bm == 0) { /* From (n1 >= d0) /\ (the most significant bit of d0 is set), conclude (the most significant bit of n1 is set) /\ (the leading quotient digit q1 = 1). This special case is necessary, not an optimization. (Shifts counts of SI_TYPE_SIZE are undefined.) */ n1 -= d0; q1 = 1; } else { _FP_W_TYPE n2; /* Normalize. */ b = _FP_W_TYPE_SIZE - bm; d0 = d0 << bm; n2 = n1 >> b; n1 = (n1 << bm) | (n0 >> b); n0 = n0 << bm; udiv_qrnnd (q1, n1, n2, n1, d0); } /* n1 != d0... */ udiv_qrnnd (q0, n0, n1, n0, d0); /* Remainder in n0 >> bm. */ } r0 = n0 >> bm; r1 = 0; #endif /* UDIV_NEEDS_NORMALIZATION */ } else { if (d1 > n1) { /* 00 = nn / DD */ q0 = 0; q1 = 0; /* Remainder in n1n0. */ r0 = n0; r1 = n1; } else { /* 0q = NN / dd */ count_leading_zeros (bm, d1); if (bm == 0) { /* From (n1 >= d1) /\ (the most significant bit of d1 is set), conclude (the most significant bit of n1 is set) /\ (the quotient digit q0 = 0 or 1). This special case is necessary, not an optimization. */ /* The condition on the next line takes advantage of that n1 >= d1 (true due to program flow). */ if (n1 > d1 || n0 >= d0) { q0 = 1; sub_ddmmss (n1, n0, n1, n0, d1, d0); } else q0 = 0; q1 = 0; r0 = n0; r1 = n1; } else { _FP_W_TYPE m1, m0, n2; /* Normalize. */ b = _FP_W_TYPE_SIZE - bm; d1 = (d1 << bm) | (d0 >> b); d0 = d0 << bm; n2 = n1 >> b; n1 = (n1 << bm) | (n0 >> b); n0 = n0 << bm; udiv_qrnnd (q0, n1, n2, n1, d1); umul_ppmm (m1, m0, q0, d0); if (m1 > n1 || (m1 == n1 && m0 > n0)) { q0--; sub_ddmmss (m1, m0, m1, m0, d1, d0); } q1 = 0; /* Remainder in (n1n0 - m1m0) >> bm. */ sub_ddmmss (n1, n0, n1, n0, m1, m0); r0 = (n1 << b) | (n0 >> bm); r1 = n1 >> bm; } } } q[0] = q0; q[1] = q1; r[0] = r0, r[1] = r1; }