qemu-e2k/target-i386/shift_helper_template.h
Paolo Bonzini f5847c912d target-i386: compute eflags outside rcl/rcr helper
Always compute EFLAGS first since it is needed whenever
the shift is non-zero, i.e. most of the time.  This makes it possible
to remove some writes of CC_OP_EFLAGS to cpu_cc_op and more importantly
removes cases where s->cc_op becomes CC_OP_DYNAMIC.  Also, we can
remove cc_tmp and just modify cc_src from within the helper.

Finally, always follow gen_compute_eflags(cpu_cc_src) by setting s->cc_op
and discarding cpu_cc_dst.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-02-18 15:03:56 -08:00

109 lines
2.8 KiB
C

/*
* x86 shift 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 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))
#define SHIFT_MASK (DATA_BITS - 1)
#if DATA_BITS <= 32
#define SHIFT1_MASK 0x1f
#else
#define SHIFT1_MASK 0x3f
#endif
#if DATA_BITS == 8
#define SUFFIX b
#define DATA_MASK 0xff
#elif DATA_BITS == 16
#define SUFFIX w
#define DATA_MASK 0xffff
#elif DATA_BITS == 32
#define SUFFIX l
#define DATA_MASK 0xffffffff
#elif DATA_BITS == 64
#define SUFFIX q
#define DATA_MASK 0xffffffffffffffffULL
#else
#error unhandled operand size
#endif
target_ulong glue(helper_rcl, SUFFIX)(CPUX86State *env, target_ulong t0,
target_ulong t1)
{
int count, eflags;
target_ulong src;
target_long res;
count = t1 & SHIFT1_MASK;
#if DATA_BITS == 16
count = rclw_table[count];
#elif DATA_BITS == 8
count = rclb_table[count];
#endif
if (count) {
eflags = env->cc_src;
t0 &= DATA_MASK;
src = t0;
res = (t0 << count) | ((target_ulong)(eflags & CC_C) << (count - 1));
if (count > 1) {
res |= t0 >> (DATA_BITS + 1 - count);
}
t0 = res;
env->cc_src = (eflags & ~(CC_C | CC_O)) |
(lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |
((src >> (DATA_BITS - count)) & CC_C);
}
return t0;
}
target_ulong glue(helper_rcr, SUFFIX)(CPUX86State *env, target_ulong t0,
target_ulong t1)
{
int count, eflags;
target_ulong src;
target_long res;
count = t1 & SHIFT1_MASK;
#if DATA_BITS == 16
count = rclw_table[count];
#elif DATA_BITS == 8
count = rclb_table[count];
#endif
if (count) {
eflags = env->cc_src;
t0 &= DATA_MASK;
src = t0;
res = (t0 >> count) |
((target_ulong)(eflags & CC_C) << (DATA_BITS - count));
if (count > 1) {
res |= t0 << (DATA_BITS + 1 - count);
}
t0 = res;
env->cc_src = (eflags & ~(CC_C | CC_O)) |
(lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |
((src >> (count - 1)) & CC_C);
}
return t0;
}
#undef DATA_BITS
#undef SHIFT_MASK
#undef SHIFT1_MASK
#undef DATA_TYPE
#undef DATA_MASK
#undef SUFFIX