root / target-i386 / int_helper.c @ 1de7afc9
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/*
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* x86 integer helpers
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*
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* Copyright (c) 2003 Fabrice Bellard
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include "cpu.h" |
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#include "qemu/host-utils.h" |
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#include "helper.h" |
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|
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//#define DEBUG_MULDIV
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|
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/* modulo 9 table */
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static const uint8_t rclb_table[32] = { |
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0, 1, 2, 3, 4, 5, 6, 7, |
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8, 0, 1, 2, 3, 4, 5, 6, |
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7, 8, 0, 1, 2, 3, 4, 5, |
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6, 7, 8, 0, 1, 2, 3, 4, |
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}; |
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|
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/* modulo 17 table */
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static const uint8_t rclw_table[32] = { |
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0, 1, 2, 3, 4, 5, 6, 7, |
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8, 9, 10, 11, 12, 13, 14, 15, |
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16, 0, 1, 2, 3, 4, 5, 6, |
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7, 8, 9, 10, 11, 12, 13, 14, |
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}; |
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|
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/* division, flags are undefined */
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|
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void helper_divb_AL(CPUX86State *env, target_ulong t0)
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{
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unsigned int num, den, q, r; |
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num = (EAX & 0xffff);
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den = (t0 & 0xff);
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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if (q > 0xff) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q &= 0xff;
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r = (num % den) & 0xff;
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EAX = (EAX & ~0xffff) | (r << 8) | q; |
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} |
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|
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void helper_idivb_AL(CPUX86State *env, target_ulong t0)
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{
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int num, den, q, r;
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num = (int16_t)EAX; |
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den = (int8_t)t0; |
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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if (q != (int8_t)q) {
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q &= 0xff;
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r = (num % den) & 0xff;
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EAX = (EAX & ~0xffff) | (r << 8) | q; |
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} |
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|
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void helper_divw_AX(CPUX86State *env, target_ulong t0)
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{
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unsigned int num, den, q, r; |
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num = (EAX & 0xffff) | ((EDX & 0xffff) << 16); |
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den = (t0 & 0xffff);
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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if (q > 0xffff) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q &= 0xffff;
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r = (num % den) & 0xffff;
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EAX = (EAX & ~0xffff) | q;
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EDX = (EDX & ~0xffff) | r;
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} |
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void helper_idivw_AX(CPUX86State *env, target_ulong t0)
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{
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int num, den, q, r;
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num = (EAX & 0xffff) | ((EDX & 0xffff) << 16); |
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den = (int16_t)t0; |
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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if (q != (int16_t)q) {
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q &= 0xffff;
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r = (num % den) & 0xffff;
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EAX = (EAX & ~0xffff) | q;
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EDX = (EDX & ~0xffff) | r;
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} |
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void helper_divl_EAX(CPUX86State *env, target_ulong t0)
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{
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unsigned int den, r; |
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uint64_t num, q; |
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num = ((uint32_t)EAX) | ((uint64_t)((uint32_t)EDX) << 32);
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den = t0; |
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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r = (num % den); |
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if (q > 0xffffffff) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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EAX = (uint32_t)q; |
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EDX = (uint32_t)r; |
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} |
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void helper_idivl_EAX(CPUX86State *env, target_ulong t0)
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{
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int den, r;
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int64_t num, q; |
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num = ((uint32_t)EAX) | ((uint64_t)((uint32_t)EDX) << 32);
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den = t0; |
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if (den == 0) { |
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raise_exception(env, EXCP00_DIVZ); |
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} |
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q = (num / den); |
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r = (num % den); |
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if (q != (int32_t)q) {
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raise_exception(env, EXCP00_DIVZ); |
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} |
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EAX = (uint32_t)q; |
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EDX = (uint32_t)r; |
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} |
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/* bcd */
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/* XXX: exception */
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void helper_aam(CPUX86State *env, int base) |
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{
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int al, ah;
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al = EAX & 0xff;
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ah = al / base; |
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al = al % base; |
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EAX = (EAX & ~0xffff) | al | (ah << 8); |
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CC_DST = al; |
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} |
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void helper_aad(CPUX86State *env, int base) |
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{
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int al, ah;
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al = EAX & 0xff;
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ah = (EAX >> 8) & 0xff; |
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al = ((ah * base) + al) & 0xff;
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EAX = (EAX & ~0xffff) | al;
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CC_DST = al; |
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} |
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void helper_aaa(CPUX86State *env)
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{
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int icarry;
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int al, ah, af;
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int eflags;
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eflags = cpu_cc_compute_all(env, CC_OP); |
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af = eflags & CC_A; |
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al = EAX & 0xff;
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ah = (EAX >> 8) & 0xff; |
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icarry = (al > 0xf9);
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if (((al & 0x0f) > 9) || af) { |
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al = (al + 6) & 0x0f; |
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ah = (ah + 1 + icarry) & 0xff; |
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eflags |= CC_C | CC_A; |
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} else {
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eflags &= ~(CC_C | CC_A); |
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al &= 0x0f;
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} |
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EAX = (EAX & ~0xffff) | al | (ah << 8); |
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CC_SRC = eflags; |
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} |
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void helper_aas(CPUX86State *env)
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{
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int icarry;
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int al, ah, af;
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int eflags;
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eflags = cpu_cc_compute_all(env, CC_OP); |
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af = eflags & CC_A; |
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al = EAX & 0xff;
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ah = (EAX >> 8) & 0xff; |
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icarry = (al < 6);
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if (((al & 0x0f) > 9) || af) { |
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al = (al - 6) & 0x0f; |
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ah = (ah - 1 - icarry) & 0xff; |
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eflags |= CC_C | CC_A; |
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} else {
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eflags &= ~(CC_C | CC_A); |
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al &= 0x0f;
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} |
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EAX = (EAX & ~0xffff) | al | (ah << 8); |
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CC_SRC = eflags; |
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} |
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void helper_daa(CPUX86State *env)
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{
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int old_al, al, af, cf;
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int eflags;
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eflags = cpu_cc_compute_all(env, CC_OP); |
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cf = eflags & CC_C; |
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af = eflags & CC_A; |
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old_al = al = EAX & 0xff;
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eflags = 0;
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if (((al & 0x0f) > 9) || af) { |
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al = (al + 6) & 0xff; |
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eflags |= CC_A; |
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} |
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if ((old_al > 0x99) || cf) { |
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al = (al + 0x60) & 0xff; |
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eflags |= CC_C; |
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} |
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EAX = (EAX & ~0xff) | al;
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/* well, speed is not an issue here, so we compute the flags by hand */
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eflags |= (al == 0) << 6; /* zf */ |
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eflags |= parity_table[al]; /* pf */
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eflags |= (al & 0x80); /* sf */ |
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CC_SRC = eflags; |
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} |
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void helper_das(CPUX86State *env)
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{
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int al, al1, af, cf;
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int eflags;
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eflags = cpu_cc_compute_all(env, CC_OP); |
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cf = eflags & CC_C; |
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af = eflags & CC_A; |
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al = EAX & 0xff;
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eflags = 0;
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al1 = al; |
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if (((al & 0x0f) > 9) || af) { |
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eflags |= CC_A; |
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if (al < 6 || cf) { |
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eflags |= CC_C; |
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} |
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al = (al - 6) & 0xff; |
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} |
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if ((al1 > 0x99) || cf) { |
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al = (al - 0x60) & 0xff; |
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eflags |= CC_C; |
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} |
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EAX = (EAX & ~0xff) | al;
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/* well, speed is not an issue here, so we compute the flags by hand */
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eflags |= (al == 0) << 6; /* zf */ |
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eflags |= parity_table[al]; /* pf */
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eflags |= (al & 0x80); /* sf */ |
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CC_SRC = eflags; |
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} |
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#ifdef TARGET_X86_64
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static void add128(uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b) |
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{
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*plow += a; |
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/* carry test */
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if (*plow < a) {
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(*phigh)++; |
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} |
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*phigh += b; |
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} |
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|
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static void neg128(uint64_t *plow, uint64_t *phigh) |
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{
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*plow = ~*plow; |
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*phigh = ~*phigh; |
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add128(plow, phigh, 1, 0); |
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} |
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|
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/* return TRUE if overflow */
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static int div64(uint64_t *plow, uint64_t *phigh, uint64_t b) |
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{
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uint64_t q, r, a1, a0; |
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int i, qb, ab;
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|
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a0 = *plow; |
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a1 = *phigh; |
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if (a1 == 0) { |
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q = a0 / b; |
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r = a0 % b; |
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*plow = q; |
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*phigh = r; |
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} else {
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if (a1 >= b) {
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return 1; |
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} |
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/* XXX: use a better algorithm */
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for (i = 0; i < 64; i++) { |
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ab = a1 >> 63;
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a1 = (a1 << 1) | (a0 >> 63); |
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if (ab || a1 >= b) {
|
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a1 -= b; |
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qb = 1;
|
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} else {
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qb = 0;
|
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} |
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a0 = (a0 << 1) | qb;
|
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} |
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#if defined(DEBUG_MULDIV)
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printf("div: 0x%016" PRIx64 "%016" PRIx64 " / 0x%016" PRIx64 |
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": q=0x%016" PRIx64 " r=0x%016" PRIx64 "\n", |
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*phigh, *plow, b, a0, a1); |
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#endif
|
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*plow = a0; |
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*phigh = a1; |
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} |
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return 0; |
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} |
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|
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/* return TRUE if overflow */
|
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static int idiv64(uint64_t *plow, uint64_t *phigh, int64_t b) |
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{
|
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int sa, sb;
|
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|
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sa = ((int64_t)*phigh < 0);
|
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if (sa) {
|
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neg128(plow, phigh); |
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} |
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sb = (b < 0);
|
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if (sb) {
|
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b = -b; |
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} |
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if (div64(plow, phigh, b) != 0) { |
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return 1; |
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} |
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if (sa ^ sb) {
|
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if (*plow > (1ULL << 63)) { |
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return 1; |
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} |
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*plow = -*plow; |
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} else {
|
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if (*plow >= (1ULL << 63)) { |
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return 1; |
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} |
| 370 |
} |
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if (sa) {
|
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*phigh = -*phigh; |
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} |
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return 0; |
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} |
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|
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void helper_mulq_EAX_T0(CPUX86State *env, target_ulong t0)
|
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{
|
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uint64_t r0, r1; |
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|
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mulu64(&r0, &r1, EAX, t0); |
| 382 |
EAX = r0; |
| 383 |
EDX = r1; |
| 384 |
CC_DST = r0; |
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CC_SRC = r1; |
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} |
| 387 |
|
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void helper_imulq_EAX_T0(CPUX86State *env, target_ulong t0)
|
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{
|
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uint64_t r0, r1; |
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|
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muls64(&r0, &r1, EAX, t0); |
| 393 |
EAX = r0; |
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EDX = r1; |
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CC_DST = r0; |
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CC_SRC = ((int64_t)r1 != ((int64_t)r0 >> 63));
|
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} |
| 398 |
|
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target_ulong helper_imulq_T0_T1(CPUX86State *env, target_ulong t0, |
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target_ulong t1) |
| 401 |
{
|
| 402 |
uint64_t r0, r1; |
| 403 |
|
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muls64(&r0, &r1, t0, t1); |
| 405 |
CC_DST = r0; |
| 406 |
CC_SRC = ((int64_t)r1 != ((int64_t)r0 >> 63));
|
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return r0;
|
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} |
| 409 |
|
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void helper_divq_EAX(CPUX86State *env, target_ulong t0)
|
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{
|
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uint64_t r0, r1; |
| 413 |
|
| 414 |
if (t0 == 0) { |
| 415 |
raise_exception(env, EXCP00_DIVZ); |
| 416 |
} |
| 417 |
r0 = EAX; |
| 418 |
r1 = EDX; |
| 419 |
if (div64(&r0, &r1, t0)) {
|
| 420 |
raise_exception(env, EXCP00_DIVZ); |
| 421 |
} |
| 422 |
EAX = r0; |
| 423 |
EDX = r1; |
| 424 |
} |
| 425 |
|
| 426 |
void helper_idivq_EAX(CPUX86State *env, target_ulong t0)
|
| 427 |
{
|
| 428 |
uint64_t r0, r1; |
| 429 |
|
| 430 |
if (t0 == 0) { |
| 431 |
raise_exception(env, EXCP00_DIVZ); |
| 432 |
} |
| 433 |
r0 = EAX; |
| 434 |
r1 = EDX; |
| 435 |
if (idiv64(&r0, &r1, t0)) {
|
| 436 |
raise_exception(env, EXCP00_DIVZ); |
| 437 |
} |
| 438 |
EAX = r0; |
| 439 |
EDX = r1; |
| 440 |
} |
| 441 |
#endif
|
| 442 |
|
| 443 |
/* bit operations */
|
| 444 |
target_ulong helper_bsf(target_ulong t0) |
| 445 |
{
|
| 446 |
int count;
|
| 447 |
target_ulong res; |
| 448 |
|
| 449 |
res = t0; |
| 450 |
count = 0;
|
| 451 |
while ((res & 1) == 0) { |
| 452 |
count++; |
| 453 |
res >>= 1;
|
| 454 |
} |
| 455 |
return count;
|
| 456 |
} |
| 457 |
|
| 458 |
target_ulong helper_lzcnt(target_ulong t0, int wordsize)
|
| 459 |
{
|
| 460 |
int count;
|
| 461 |
target_ulong res, mask; |
| 462 |
|
| 463 |
if (wordsize > 0 && t0 == 0) { |
| 464 |
return wordsize;
|
| 465 |
} |
| 466 |
res = t0; |
| 467 |
count = TARGET_LONG_BITS - 1;
|
| 468 |
mask = (target_ulong)1 << (TARGET_LONG_BITS - 1); |
| 469 |
while ((res & mask) == 0) { |
| 470 |
count--; |
| 471 |
res <<= 1;
|
| 472 |
} |
| 473 |
if (wordsize > 0) { |
| 474 |
return wordsize - 1 - count; |
| 475 |
} |
| 476 |
return count;
|
| 477 |
} |
| 478 |
|
| 479 |
target_ulong helper_bsr(target_ulong t0) |
| 480 |
{
|
| 481 |
return helper_lzcnt(t0, 0); |
| 482 |
} |
| 483 |
|
| 484 |
#define SHIFT 0 |
| 485 |
#include "shift_helper_template.h" |
| 486 |
#undef SHIFT
|
| 487 |
|
| 488 |
#define SHIFT 1 |
| 489 |
#include "shift_helper_template.h" |
| 490 |
#undef SHIFT
|
| 491 |
|
| 492 |
#define SHIFT 2 |
| 493 |
#include "shift_helper_template.h" |
| 494 |
#undef SHIFT
|
| 495 |
|
| 496 |
#ifdef TARGET_X86_64
|
| 497 |
#define SHIFT 3 |
| 498 |
#include "shift_helper_template.h" |
| 499 |
#undef SHIFT
|
| 500 |
#endif
|