| /* |
| * x86 condition code helpers |
| * |
| * Copyright (c) 2008 Fabrice Bellard |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #define DATA_BITS (1 << (3 + SHIFT)) |
| |
| #if DATA_BITS == 8 |
| #define SUFFIX b |
| #define DATA_TYPE uint8_t |
| #elif DATA_BITS == 16 |
| #define SUFFIX w |
| #define DATA_TYPE uint16_t |
| #elif DATA_BITS == 32 |
| #define SUFFIX l |
| #define DATA_TYPE uint32_t |
| #elif DATA_BITS == 64 |
| #define SUFFIX q |
| #define DATA_TYPE uint64_t |
| #else |
| #error unhandled operand size |
| #endif |
| |
| #define SIGN_MASK (((DATA_TYPE)1) << (DATA_BITS - 1)) |
| |
| /* dynamic flags computation */ |
| |
| static int glue(compute_all_add, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src2 = dst - src1; |
| |
| cf = dst < src1; |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & CC_A; |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = lshift((src1 ^ src2 ^ -1) & (src1 ^ dst), 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_add, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| return dst < src1; |
| } |
| |
| static int glue(compute_all_adc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1, |
| DATA_TYPE src3) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src2 = dst - src1 - src3; |
| |
| cf = (src3 ? dst <= src1 : dst < src1); |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & 0x10; |
| zf = (dst == 0) << 6; |
| sf = lshift(dst, 8 - DATA_BITS) & 0x80; |
| of = lshift((src1 ^ src2 ^ -1) & (src1 ^ dst), 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_adc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1, |
| DATA_TYPE src3) |
| { |
| return src3 ? dst <= src1 : dst < src1; |
| } |
| |
| static int glue(compute_all_sub, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src1 = dst + src2; |
| |
| cf = src1 < src2; |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & CC_A; |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = lshift((src1 ^ src2) & (src1 ^ dst), 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_sub, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2) |
| { |
| DATA_TYPE src1 = dst + src2; |
| |
| return src1 < src2; |
| } |
| |
| static int glue(compute_all_sbb, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2, |
| DATA_TYPE src3) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src1 = dst + src2 + src3; |
| |
| cf = (src3 ? src1 <= src2 : src1 < src2); |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & 0x10; |
| zf = (dst == 0) << 6; |
| sf = lshift(dst, 8 - DATA_BITS) & 0x80; |
| of = lshift((src1 ^ src2) & (src1 ^ dst), 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_sbb, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2, |
| DATA_TYPE src3) |
| { |
| DATA_TYPE src1 = dst + src2 + src3; |
| |
| return (src3 ? src1 <= src2 : src1 < src2); |
| } |
| |
| static int glue(compute_all_logic, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| |
| cf = 0; |
| pf = parity_table[(uint8_t)dst]; |
| af = 0; |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = 0; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_all_inc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src2; |
| |
| cf = src1; |
| src1 = dst - 1; |
| src2 = 1; |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & CC_A; |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = (dst == SIGN_MASK) * CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_all_dec, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| DATA_TYPE src2; |
| |
| cf = src1; |
| src1 = dst + 1; |
| src2 = 1; |
| pf = parity_table[(uint8_t)dst]; |
| af = (dst ^ src1 ^ src2) & CC_A; |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = (dst == SIGN_MASK - 1) * CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_all_shl, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| |
| cf = (src1 >> (DATA_BITS - 1)) & CC_C; |
| pf = parity_table[(uint8_t)dst]; |
| af = 0; /* undefined */ |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| /* of is defined iff shift count == 1 */ |
| of = lshift(src1 ^ dst, 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_shl, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| return (src1 >> (DATA_BITS - 1)) & CC_C; |
| } |
| |
| static int glue(compute_all_sar, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| |
| cf = src1 & 1; |
| pf = parity_table[(uint8_t)dst]; |
| af = 0; /* undefined */ |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| /* of is defined iff shift count == 1 */ |
| of = lshift(src1 ^ dst, 12 - DATA_BITS) & CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| /* NOTE: we compute the flags like the P4. On olders CPUs, only OF and |
| CF are modified and it is slower to do that. Note as well that we |
| don't truncate SRC1 for computing carry to DATA_TYPE. */ |
| static int glue(compute_all_mul, SUFFIX)(DATA_TYPE dst, target_long src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| |
| cf = (src1 != 0); |
| pf = parity_table[(uint8_t)dst]; |
| af = 0; /* undefined */ |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = cf * CC_O; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_all_bmilg, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| int cf, pf, af, zf, sf, of; |
| |
| cf = (src1 == 0); |
| pf = 0; /* undefined */ |
| af = 0; /* undefined */ |
| zf = (dst == 0) * CC_Z; |
| sf = lshift(dst, 8 - DATA_BITS) & CC_S; |
| of = 0; |
| return cf | pf | af | zf | sf | of; |
| } |
| |
| static int glue(compute_c_bmilg, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) |
| { |
| return src1 == 0; |
| } |
| |
| #undef DATA_BITS |
| #undef SIGN_MASK |
| #undef DATA_TYPE |
| #undef DATA_MASK |
| #undef SUFFIX |