qemu-e2k/target/sparc/helper.c

255 lines
6.0 KiB
C

/*
* Misc Sparc helpers
*
* Copyright (c) 2003-2005 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/>.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/exec-all.h"
#include "qemu/timer.h"
#include "qemu/host-utils.h"
#include "exec/helper-proto.h"
void cpu_raise_exception_ra(CPUSPARCState *env, int tt, uintptr_t ra)
{
CPUState *cs = env_cpu(env);
cs->exception_index = tt;
cpu_loop_exit_restore(cs, ra);
}
void helper_raise_exception(CPUSPARCState *env, int tt)
{
CPUState *cs = env_cpu(env);
cs->exception_index = tt;
cpu_loop_exit(cs);
}
void helper_debug(CPUSPARCState *env)
{
CPUState *cs = env_cpu(env);
cs->exception_index = EXCP_DEBUG;
cpu_loop_exit(cs);
}
#ifdef TARGET_SPARC64
void helper_tick_set_count(void *opaque, uint64_t count)
{
#if !defined(CONFIG_USER_ONLY)
cpu_tick_set_count(opaque, count);
#endif
}
uint64_t helper_tick_get_count(CPUSPARCState *env, void *opaque, int mem_idx)
{
#if !defined(CONFIG_USER_ONLY)
CPUTimer *timer = opaque;
if (timer->npt && mem_idx < MMU_KERNEL_IDX) {
cpu_raise_exception_ra(env, TT_PRIV_INSN, GETPC());
}
return cpu_tick_get_count(timer);
#else
/* In user-mode, QEMU_CLOCK_VIRTUAL doesn't exist.
Just pass through the host cpu clock ticks. */
return cpu_get_host_ticks();
#endif
}
void helper_tick_set_limit(void *opaque, uint64_t limit)
{
#if !defined(CONFIG_USER_ONLY)
cpu_tick_set_limit(opaque, limit);
#endif
}
#endif
static target_ulong do_udiv(CPUSPARCState *env, target_ulong a,
target_ulong b, int cc, uintptr_t ra)
{
int overflow = 0;
uint64_t x0;
uint32_t x1;
x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);
x1 = (b & 0xffffffff);
if (x1 == 0) {
cpu_raise_exception_ra(env, TT_DIV_ZERO, ra);
}
x0 = x0 / x1;
if (x0 > UINT32_MAX) {
x0 = UINT32_MAX;
overflow = 1;
}
if (cc) {
env->cc_dst = x0;
env->cc_src2 = overflow;
env->cc_op = CC_OP_DIV;
}
return x0;
}
target_ulong helper_udiv(CPUSPARCState *env, target_ulong a, target_ulong b)
{
return do_udiv(env, a, b, 0, GETPC());
}
target_ulong helper_udiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)
{
return do_udiv(env, a, b, 1, GETPC());
}
static target_ulong do_sdiv(CPUSPARCState *env, target_ulong a,
target_ulong b, int cc, uintptr_t ra)
{
int overflow = 0;
int64_t x0;
int32_t x1;
x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);
x1 = (b & 0xffffffff);
if (x1 == 0) {
cpu_raise_exception_ra(env, TT_DIV_ZERO, ra);
} else if (x1 == -1 && x0 == INT64_MIN) {
x0 = INT32_MAX;
overflow = 1;
} else {
x0 = x0 / x1;
if ((int32_t) x0 != x0) {
x0 = x0 < 0 ? INT32_MIN : INT32_MAX;
overflow = 1;
}
}
if (cc) {
env->cc_dst = x0;
env->cc_src2 = overflow;
env->cc_op = CC_OP_DIV;
}
return x0;
}
target_ulong helper_sdiv(CPUSPARCState *env, target_ulong a, target_ulong b)
{
return do_sdiv(env, a, b, 0, GETPC());
}
target_ulong helper_sdiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)
{
return do_sdiv(env, a, b, 1, GETPC());
}
#ifdef TARGET_SPARC64
int64_t helper_sdivx(CPUSPARCState *env, int64_t a, int64_t b)
{
if (b == 0) {
/* Raise divide by zero trap. */
cpu_raise_exception_ra(env, TT_DIV_ZERO, GETPC());
} else if (b == -1) {
/* Avoid overflow trap with i386 divide insn. */
return -a;
} else {
return a / b;
}
}
uint64_t helper_udivx(CPUSPARCState *env, uint64_t a, uint64_t b)
{
if (b == 0) {
/* Raise divide by zero trap. */
cpu_raise_exception_ra(env, TT_DIV_ZERO, GETPC());
}
return a / b;
}
#endif
target_ulong helper_taddcctv(CPUSPARCState *env, target_ulong src1,
target_ulong src2)
{
target_ulong dst;
/* Tag overflow occurs if either input has bits 0 or 1 set. */
if ((src1 | src2) & 3) {
goto tag_overflow;
}
dst = src1 + src2;
/* Tag overflow occurs if the addition overflows. */
if (~(src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {
goto tag_overflow;
}
/* Only modify the CC after any exceptions have been generated. */
env->cc_op = CC_OP_TADDTV;
env->cc_src = src1;
env->cc_src2 = src2;
env->cc_dst = dst;
return dst;
tag_overflow:
cpu_raise_exception_ra(env, TT_TOVF, GETPC());
}
target_ulong helper_tsubcctv(CPUSPARCState *env, target_ulong src1,
target_ulong src2)
{
target_ulong dst;
/* Tag overflow occurs if either input has bits 0 or 1 set. */
if ((src1 | src2) & 3) {
goto tag_overflow;
}
dst = src1 - src2;
/* Tag overflow occurs if the subtraction overflows. */
if ((src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {
goto tag_overflow;
}
/* Only modify the CC after any exceptions have been generated. */
env->cc_op = CC_OP_TSUBTV;
env->cc_src = src1;
env->cc_src2 = src2;
env->cc_dst = dst;
return dst;
tag_overflow:
cpu_raise_exception_ra(env, TT_TOVF, GETPC());
}
#ifndef TARGET_SPARC64
void helper_power_down(CPUSPARCState *env)
{
CPUState *cs = env_cpu(env);
cs->halted = 1;
cs->exception_index = EXCP_HLT;
env->pc = env->npc;
env->npc = env->pc + 4;
cpu_loop_exit(cs);
}
#endif