qemu-e2k/target/s390x/vec_fpu_helper.c

256 lines
7.8 KiB
C

/*
* QEMU TCG support -- s390x vector floating point instruction support
*
* Copyright (C) 2019 Red Hat Inc
*
* Authors:
* David Hildenbrand <david@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "cpu.h"
#include "internal.h"
#include "vec.h"
#include "tcg_s390x.h"
#include "tcg/tcg-gvec-desc.h"
#include "exec/exec-all.h"
#include "exec/helper-proto.h"
#include "fpu/softfloat.h"
#define VIC_INVALID 0x1
#define VIC_DIVBYZERO 0x2
#define VIC_OVERFLOW 0x3
#define VIC_UNDERFLOW 0x4
#define VIC_INEXACT 0x5
/* returns the VEX. If the VEX is 0, there is no trap */
static uint8_t check_ieee_exc(CPUS390XState *env, uint8_t enr, bool XxC,
uint8_t *vec_exc)
{
uint8_t vece_exc = 0, trap_exc;
unsigned qemu_exc;
/* Retrieve and clear the softfloat exceptions */
qemu_exc = env->fpu_status.float_exception_flags;
if (qemu_exc == 0) {
return 0;
}
env->fpu_status.float_exception_flags = 0;
vece_exc = s390_softfloat_exc_to_ieee(qemu_exc);
/* Add them to the vector-wide s390x exception bits */
*vec_exc |= vece_exc;
/* Check for traps and construct the VXC */
trap_exc = vece_exc & env->fpc >> 24;
if (trap_exc) {
if (trap_exc & S390_IEEE_MASK_INVALID) {
return enr << 4 | VIC_INVALID;
} else if (trap_exc & S390_IEEE_MASK_DIVBYZERO) {
return enr << 4 | VIC_DIVBYZERO;
} else if (trap_exc & S390_IEEE_MASK_OVERFLOW) {
return enr << 4 | VIC_OVERFLOW;
} else if (trap_exc & S390_IEEE_MASK_UNDERFLOW) {
return enr << 4 | VIC_UNDERFLOW;
} else if (!XxC) {
g_assert(trap_exc & S390_IEEE_MASK_INEXACT);
/* inexact has lowest priority on traps */
return enr << 4 | VIC_INEXACT;
}
}
return 0;
}
static void handle_ieee_exc(CPUS390XState *env, uint8_t vxc, uint8_t vec_exc,
uintptr_t retaddr)
{
if (vxc) {
/* on traps, the fpc flags are not updated, instruction is suppressed */
tcg_s390_vector_exception(env, vxc, retaddr);
}
if (vec_exc) {
/* indicate exceptions for all elements combined */
env->fpc |= vec_exc << 16;
}
}
typedef uint64_t (*vop64_3_fn)(uint64_t a, uint64_t b, float_status *s);
static void vop64_3(S390Vector *v1, const S390Vector *v2, const S390Vector *v3,
CPUS390XState *env, bool s, vop64_3_fn fn,
uintptr_t retaddr)
{
uint8_t vxc, vec_exc = 0;
S390Vector tmp = {};
int i;
for (i = 0; i < 2; i++) {
const uint64_t a = s390_vec_read_element64(v2, i);
const uint64_t b = s390_vec_read_element64(v3, i);
s390_vec_write_element64(&tmp, i, fn(a, b, &env->fpu_status));
vxc = check_ieee_exc(env, i, false, &vec_exc);
if (s || vxc) {
break;
}
}
handle_ieee_exc(env, vxc, vec_exc, retaddr);
*v1 = tmp;
}
static uint64_t vfa64(uint64_t a, uint64_t b, float_status *s)
{
return float64_add(a, b, s);
}
void HELPER(gvec_vfa64)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vop64_3(v1, v2, v3, env, false, vfa64, GETPC());
}
void HELPER(gvec_vfa64s)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vop64_3(v1, v2, v3, env, true, vfa64, GETPC());
}
static int wfc64(const S390Vector *v1, const S390Vector *v2,
CPUS390XState *env, bool signal, uintptr_t retaddr)
{
/* only the zero-indexed elements are compared */
const float64 a = s390_vec_read_element64(v1, 0);
const float64 b = s390_vec_read_element64(v2, 0);
uint8_t vxc, vec_exc = 0;
int cmp;
if (signal) {
cmp = float64_compare(a, b, &env->fpu_status);
} else {
cmp = float64_compare_quiet(a, b, &env->fpu_status);
}
vxc = check_ieee_exc(env, 0, false, &vec_exc);
handle_ieee_exc(env, vxc, vec_exc, retaddr);
return float_comp_to_cc(env, cmp);
}
void HELPER(gvec_wfc64)(const void *v1, const void *v2, CPUS390XState *env,
uint32_t desc)
{
env->cc_op = wfc64(v1, v2, env, false, GETPC());
}
void HELPER(gvec_wfk64)(const void *v1, const void *v2, CPUS390XState *env,
uint32_t desc)
{
env->cc_op = wfc64(v1, v2, env, true, GETPC());
}
typedef int (*vfc64_fn)(float64 a, float64 b, float_status *status);
static int vfc64(S390Vector *v1, const S390Vector *v2, const S390Vector *v3,
CPUS390XState *env, bool s, vfc64_fn fn, uintptr_t retaddr)
{
uint8_t vxc, vec_exc = 0;
S390Vector tmp = {};
int match = 0;
int i;
for (i = 0; i < 2; i++) {
const float64 a = s390_vec_read_element64(v2, i);
const float64 b = s390_vec_read_element64(v3, i);
/* swap the order of the parameters, so we can use existing functions */
if (fn(b, a, &env->fpu_status)) {
match++;
s390_vec_write_element64(&tmp, i, -1ull);
}
vxc = check_ieee_exc(env, i, false, &vec_exc);
if (s || vxc) {
break;
}
}
handle_ieee_exc(env, vxc, vec_exc, retaddr);
*v1 = tmp;
if (match) {
return s || match == 2 ? 0 : 1;
}
return 3;
}
void HELPER(gvec_vfce64)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, false, float64_eq_quiet, GETPC());
}
void HELPER(gvec_vfce64s)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, true, float64_eq_quiet, GETPC());
}
void HELPER(gvec_vfce64_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, false, float64_eq_quiet, GETPC());
}
void HELPER(gvec_vfce64s_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, true, float64_eq_quiet, GETPC());
}
void HELPER(gvec_vfch64)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, false, float64_lt_quiet, GETPC());
}
void HELPER(gvec_vfch64s)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, true, float64_lt_quiet, GETPC());
}
void HELPER(gvec_vfch64_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, false, float64_lt_quiet, GETPC());
}
void HELPER(gvec_vfch64s_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, true, float64_lt_quiet, GETPC());
}
void HELPER(gvec_vfche64)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, false, float64_le_quiet, GETPC());
}
void HELPER(gvec_vfche64s)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
vfc64(v1, v2, v3, env, true, float64_le_quiet, GETPC());
}
void HELPER(gvec_vfche64_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, false, float64_le_quiet, GETPC());
}
void HELPER(gvec_vfche64s_cc)(void *v1, const void *v2, const void *v3,
CPUS390XState *env, uint32_t desc)
{
env->cc_op = vfc64(v1, v2, v3, env, true, float64_le_quiet, GETPC());
}