// license:BSD-3-Clause // copyright-holders:Tyler J. Stachecki,Ryan Holtz inline rsp_vec_t vec_vrcp_vrsq(uint32_t iw, int32_t dp, uint32_t src, uint32_t e, uint32_t dest, uint32_t de) { // Get the element from VT. int16_t vt = m_v[src].s[e & 0x7]; uint32_t dp_input = ((uint32_t) m_div_in << 16) | (uint16_t) vt; uint32_t sp_input = vt; int32_t input = (dp) ? dp_input : sp_input; int32_t input_mask = input >> 31; int32_t data = input ^ input_mask; if (input > -32768) { data -= input_mask; } // Handle edge cases. int32_t result; if (data == 0) { result = 0x7fffffff; } else if (input == -32768) { result = 0xffff0000; } else // Main case: compute the reciprocal. { uint32_t shift = count_leading_zeros(data); uint32_t idx = (((uint64_t) data << shift) & 0x7FC00000) >> 22; if (iw & 0x4) // VRSQ { idx = ((idx | 0x200) & 0x3fe) | (shift % 2); result = rsp_divtable[idx]; result = ((0x10000 | result) << 14) >> ((31 - shift) >> 1); } else // VRCP { result = rsp_divtable[idx]; result = ((0x10000 | result) << 14) >> (31 - shift); } result = result ^ input_mask; } // Write out the results. m_div_out = result >> 16; m_v[dest].s[de & 0x7] = result; return vec_load_unshuffled_operand(m_v[dest].s); }