823 lines
20 KiB
C
823 lines
20 KiB
C
/*
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* Helpers for floating point instructions.
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*
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* Copyright (c) 2007 Jocelyn Mayer
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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 "helper.h"
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#include "fpu/softfloat.h"
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#define FP_STATUS (env->fp_status)
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void helper_setroundmode(CPUAlphaState *env, uint32_t val)
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{
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set_float_rounding_mode(val, &FP_STATUS);
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}
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void helper_setflushzero(CPUAlphaState *env, uint32_t val)
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{
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set_flush_to_zero(val, &FP_STATUS);
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}
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void helper_fp_exc_clear(CPUAlphaState *env)
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{
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set_float_exception_flags(0, &FP_STATUS);
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}
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uint32_t helper_fp_exc_get(CPUAlphaState *env)
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{
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return get_float_exception_flags(&FP_STATUS);
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}
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static inline void inline_fp_exc_raise(CPUAlphaState *env, uintptr_t retaddr,
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uint32_t exc, uint32_t regno)
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{
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if (exc) {
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uint32_t hw_exc = 0;
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if (exc & float_flag_invalid) {
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hw_exc |= EXC_M_INV;
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}
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if (exc & float_flag_divbyzero) {
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hw_exc |= EXC_M_DZE;
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}
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if (exc & float_flag_overflow) {
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hw_exc |= EXC_M_FOV;
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}
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if (exc & float_flag_underflow) {
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hw_exc |= EXC_M_UNF;
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}
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if (exc & float_flag_inexact) {
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hw_exc |= EXC_M_INE;
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}
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arith_excp(env, retaddr, hw_exc, 1ull << regno);
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}
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}
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/* Raise exceptions for ieee fp insns without software completion.
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In that case there are no exceptions that don't trap; the mask
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doesn't apply. */
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void helper_fp_exc_raise(CPUAlphaState *env, uint32_t exc, uint32_t regno)
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{
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inline_fp_exc_raise(env, GETPC(), exc, regno);
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}
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/* Raise exceptions for ieee fp insns with software completion. */
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void helper_fp_exc_raise_s(CPUAlphaState *env, uint32_t exc, uint32_t regno)
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{
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if (exc) {
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env->fpcr_exc_status |= exc;
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exc &= ~env->fpcr_exc_mask;
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inline_fp_exc_raise(env, GETPC(), exc, regno);
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}
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}
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/* Input handing without software completion. Trap for all
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non-finite numbers. */
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void helper_ieee_input(CPUAlphaState *env, uint64_t val)
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{
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uint32_t exp = (uint32_t)(val >> 52) & 0x7ff;
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uint64_t frac = val & 0xfffffffffffffull;
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if (exp == 0) {
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/* Denormals without DNZ set raise an exception. */
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if (frac != 0 && !env->fp_status.flush_inputs_to_zero) {
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arith_excp(env, GETPC(), EXC_M_UNF, 0);
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}
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} else if (exp == 0x7ff) {
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/* Infinity or NaN. */
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/* ??? I'm not sure these exception bit flags are correct. I do
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know that the Linux kernel, at least, doesn't rely on them and
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just emulates the insn to figure out what exception to use. */
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arith_excp(env, GETPC(), frac ? EXC_M_INV : EXC_M_FOV, 0);
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}
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}
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/* Similar, but does not trap for infinities. Used for comparisons. */
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void helper_ieee_input_cmp(CPUAlphaState *env, uint64_t val)
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{
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uint32_t exp = (uint32_t)(val >> 52) & 0x7ff;
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uint64_t frac = val & 0xfffffffffffffull;
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if (exp == 0) {
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/* Denormals without DNZ set raise an exception. */
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if (frac != 0 && !env->fp_status.flush_inputs_to_zero) {
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arith_excp(env, GETPC(), EXC_M_UNF, 0);
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}
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} else if (exp == 0x7ff && frac) {
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/* NaN. */
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arith_excp(env, GETPC(), EXC_M_INV, 0);
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}
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}
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/* F floating (VAX) */
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static uint64_t float32_to_f(float32 fa)
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{
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uint64_t r, exp, mant, sig;
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CPU_FloatU a;
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a.f = fa;
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sig = ((uint64_t)a.l & 0x80000000) << 32;
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exp = (a.l >> 23) & 0xff;
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mant = ((uint64_t)a.l & 0x007fffff) << 29;
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if (exp == 255) {
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/* NaN or infinity */
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r = 1; /* VAX dirty zero */
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} else if (exp == 0) {
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if (mant == 0) {
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/* Zero */
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r = 0;
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} else {
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/* Denormalized */
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r = sig | ((exp + 1) << 52) | mant;
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}
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} else {
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if (exp >= 253) {
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/* Overflow */
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r = 1; /* VAX dirty zero */
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} else {
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r = sig | ((exp + 2) << 52);
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}
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}
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return r;
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}
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static float32 f_to_float32(CPUAlphaState *env, uintptr_t retaddr, uint64_t a)
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{
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uint32_t exp, mant_sig;
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CPU_FloatU r;
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exp = ((a >> 55) & 0x80) | ((a >> 52) & 0x7f);
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mant_sig = ((a >> 32) & 0x80000000) | ((a >> 29) & 0x007fffff);
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if (unlikely(!exp && mant_sig)) {
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/* Reserved operands / Dirty zero */
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dynamic_excp(env, retaddr, EXCP_OPCDEC, 0);
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}
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if (exp < 3) {
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/* Underflow */
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r.l = 0;
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} else {
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r.l = ((exp - 2) << 23) | mant_sig;
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}
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return r.f;
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}
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uint32_t helper_f_to_memory(uint64_t a)
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{
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uint32_t r;
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r = (a & 0x00001fffe0000000ull) >> 13;
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r |= (a & 0x07ffe00000000000ull) >> 45;
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r |= (a & 0xc000000000000000ull) >> 48;
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return r;
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}
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uint64_t helper_memory_to_f(uint32_t a)
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{
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uint64_t r;
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r = ((uint64_t)(a & 0x0000c000)) << 48;
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r |= ((uint64_t)(a & 0x003fffff)) << 45;
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r |= ((uint64_t)(a & 0xffff0000)) << 13;
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if (!(a & 0x00004000)) {
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r |= 0x7ll << 59;
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}
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return r;
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}
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/* ??? Emulating VAX arithmetic with IEEE arithmetic is wrong. We should
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either implement VAX arithmetic properly or just signal invalid opcode. */
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uint64_t helper_addf(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = f_to_float32(env, GETPC(), a);
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fb = f_to_float32(env, GETPC(), b);
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fr = float32_add(fa, fb, &FP_STATUS);
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return float32_to_f(fr);
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}
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uint64_t helper_subf(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = f_to_float32(env, GETPC(), a);
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fb = f_to_float32(env, GETPC(), b);
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fr = float32_sub(fa, fb, &FP_STATUS);
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return float32_to_f(fr);
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}
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uint64_t helper_mulf(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = f_to_float32(env, GETPC(), a);
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fb = f_to_float32(env, GETPC(), b);
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fr = float32_mul(fa, fb, &FP_STATUS);
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return float32_to_f(fr);
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}
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uint64_t helper_divf(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = f_to_float32(env, GETPC(), a);
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fb = f_to_float32(env, GETPC(), b);
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fr = float32_div(fa, fb, &FP_STATUS);
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return float32_to_f(fr);
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}
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uint64_t helper_sqrtf(CPUAlphaState *env, uint64_t t)
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{
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float32 ft, fr;
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ft = f_to_float32(env, GETPC(), t);
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fr = float32_sqrt(ft, &FP_STATUS);
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return float32_to_f(fr);
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}
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/* G floating (VAX) */
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static uint64_t float64_to_g(float64 fa)
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{
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uint64_t r, exp, mant, sig;
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CPU_DoubleU a;
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a.d = fa;
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sig = a.ll & 0x8000000000000000ull;
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exp = (a.ll >> 52) & 0x7ff;
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mant = a.ll & 0x000fffffffffffffull;
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if (exp == 2047) {
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/* NaN or infinity */
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r = 1; /* VAX dirty zero */
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} else if (exp == 0) {
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if (mant == 0) {
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/* Zero */
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r = 0;
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} else {
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/* Denormalized */
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r = sig | ((exp + 1) << 52) | mant;
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}
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} else {
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if (exp >= 2045) {
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/* Overflow */
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r = 1; /* VAX dirty zero */
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} else {
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r = sig | ((exp + 2) << 52);
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}
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}
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return r;
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}
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static float64 g_to_float64(CPUAlphaState *env, uintptr_t retaddr, uint64_t a)
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{
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uint64_t exp, mant_sig;
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CPU_DoubleU r;
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exp = (a >> 52) & 0x7ff;
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mant_sig = a & 0x800fffffffffffffull;
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if (!exp && mant_sig) {
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/* Reserved operands / Dirty zero */
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dynamic_excp(env, retaddr, EXCP_OPCDEC, 0);
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}
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if (exp < 3) {
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/* Underflow */
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r.ll = 0;
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} else {
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r.ll = ((exp - 2) << 52) | mant_sig;
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}
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return r.d;
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}
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uint64_t helper_g_to_memory(uint64_t a)
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{
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uint64_t r;
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r = (a & 0x000000000000ffffull) << 48;
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r |= (a & 0x00000000ffff0000ull) << 16;
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r |= (a & 0x0000ffff00000000ull) >> 16;
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r |= (a & 0xffff000000000000ull) >> 48;
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return r;
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}
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uint64_t helper_memory_to_g(uint64_t a)
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{
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uint64_t r;
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r = (a & 0x000000000000ffffull) << 48;
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r |= (a & 0x00000000ffff0000ull) << 16;
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r |= (a & 0x0000ffff00000000ull) >> 16;
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r |= (a & 0xffff000000000000ull) >> 48;
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return r;
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}
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uint64_t helper_addg(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float64 fa, fb, fr;
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fa = g_to_float64(env, GETPC(), a);
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fb = g_to_float64(env, GETPC(), b);
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fr = float64_add(fa, fb, &FP_STATUS);
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return float64_to_g(fr);
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}
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uint64_t helper_subg(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float64 fa, fb, fr;
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fa = g_to_float64(env, GETPC(), a);
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fb = g_to_float64(env, GETPC(), b);
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fr = float64_sub(fa, fb, &FP_STATUS);
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return float64_to_g(fr);
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}
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uint64_t helper_mulg(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float64 fa, fb, fr;
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fa = g_to_float64(env, GETPC(), a);
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fb = g_to_float64(env, GETPC(), b);
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fr = float64_mul(fa, fb, &FP_STATUS);
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return float64_to_g(fr);
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}
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uint64_t helper_divg(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float64 fa, fb, fr;
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fa = g_to_float64(env, GETPC(), a);
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fb = g_to_float64(env, GETPC(), b);
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fr = float64_div(fa, fb, &FP_STATUS);
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return float64_to_g(fr);
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}
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uint64_t helper_sqrtg(CPUAlphaState *env, uint64_t a)
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{
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float64 fa, fr;
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fa = g_to_float64(env, GETPC(), a);
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fr = float64_sqrt(fa, &FP_STATUS);
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return float64_to_g(fr);
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}
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/* S floating (single) */
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/* Taken from linux/arch/alpha/kernel/traps.c, s_mem_to_reg. */
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static inline uint64_t float32_to_s_int(uint32_t fi)
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{
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uint32_t frac = fi & 0x7fffff;
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uint32_t sign = fi >> 31;
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uint32_t exp_msb = (fi >> 30) & 1;
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uint32_t exp_low = (fi >> 23) & 0x7f;
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uint32_t exp;
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exp = (exp_msb << 10) | exp_low;
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if (exp_msb) {
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if (exp_low == 0x7f) {
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exp = 0x7ff;
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}
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} else {
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if (exp_low != 0x00) {
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exp |= 0x380;
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}
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}
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return (((uint64_t)sign << 63)
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| ((uint64_t)exp << 52)
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| ((uint64_t)frac << 29));
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}
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static inline uint64_t float32_to_s(float32 fa)
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{
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CPU_FloatU a;
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a.f = fa;
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return float32_to_s_int(a.l);
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}
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static inline uint32_t s_to_float32_int(uint64_t a)
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{
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return ((a >> 32) & 0xc0000000) | ((a >> 29) & 0x3fffffff);
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}
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static inline float32 s_to_float32(uint64_t a)
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{
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CPU_FloatU r;
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r.l = s_to_float32_int(a);
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return r.f;
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}
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uint32_t helper_s_to_memory(uint64_t a)
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{
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return s_to_float32_int(a);
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}
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uint64_t helper_memory_to_s(uint32_t a)
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{
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return float32_to_s_int(a);
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}
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uint64_t helper_adds(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = s_to_float32(a);
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fb = s_to_float32(b);
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fr = float32_add(fa, fb, &FP_STATUS);
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return float32_to_s(fr);
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}
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uint64_t helper_subs(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = s_to_float32(a);
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fb = s_to_float32(b);
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fr = float32_sub(fa, fb, &FP_STATUS);
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return float32_to_s(fr);
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}
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uint64_t helper_muls(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = s_to_float32(a);
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fb = s_to_float32(b);
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fr = float32_mul(fa, fb, &FP_STATUS);
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return float32_to_s(fr);
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}
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uint64_t helper_divs(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float32 fa, fb, fr;
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fa = s_to_float32(a);
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fb = s_to_float32(b);
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fr = float32_div(fa, fb, &FP_STATUS);
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return float32_to_s(fr);
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}
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uint64_t helper_sqrts(CPUAlphaState *env, uint64_t a)
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{
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float32 fa, fr;
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fa = s_to_float32(a);
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fr = float32_sqrt(fa, &FP_STATUS);
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return float32_to_s(fr);
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}
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/* T floating (double) */
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static inline float64 t_to_float64(uint64_t a)
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{
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/* Memory format is the same as float64 */
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CPU_DoubleU r;
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r.ll = a;
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return r.d;
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}
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static inline uint64_t float64_to_t(float64 fa)
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{
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/* Memory format is the same as float64 */
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CPU_DoubleU r;
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r.d = fa;
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return r.ll;
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}
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uint64_t helper_addt(CPUAlphaState *env, uint64_t a, uint64_t b)
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{
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float64 fa, fb, fr;
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fa = t_to_float64(a);
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fb = t_to_float64(b);
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fr = float64_add(fa, fb, &FP_STATUS);
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return float64_to_t(fr);
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}
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|
|
uint64_t helper_subt(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb, fr;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
fr = float64_sub(fa, fb, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
uint64_t helper_mult(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb, fr;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
fr = float64_mul(fa, fb, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
uint64_t helper_divt(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb, fr;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
fr = float64_div(fa, fb, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
uint64_t helper_sqrtt(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fa, fr;
|
|
|
|
fa = t_to_float64(a);
|
|
fr = float64_sqrt(fa, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
/* Comparisons */
|
|
uint64_t helper_cmptun(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
|
|
if (float64_unordered_quiet(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmpteq(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
|
|
if (float64_eq_quiet(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmptle(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
|
|
if (float64_le(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmptlt(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = t_to_float64(a);
|
|
fb = t_to_float64(b);
|
|
|
|
if (float64_lt(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmpgeq(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = g_to_float64(env, GETPC(), a);
|
|
fb = g_to_float64(env, GETPC(), b);
|
|
|
|
if (float64_eq_quiet(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmpgle(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = g_to_float64(env, GETPC(), a);
|
|
fb = g_to_float64(env, GETPC(), b);
|
|
|
|
if (float64_le(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t helper_cmpglt(CPUAlphaState *env, uint64_t a, uint64_t b)
|
|
{
|
|
float64 fa, fb;
|
|
|
|
fa = g_to_float64(env, GETPC(), a);
|
|
fb = g_to_float64(env, GETPC(), b);
|
|
|
|
if (float64_lt(fa, fb, &FP_STATUS)) {
|
|
return 0x4000000000000000ULL;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Floating point format conversion */
|
|
uint64_t helper_cvtts(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fa;
|
|
float32 fr;
|
|
|
|
fa = t_to_float64(a);
|
|
fr = float64_to_float32(fa, &FP_STATUS);
|
|
return float32_to_s(fr);
|
|
}
|
|
|
|
uint64_t helper_cvtst(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float32 fa;
|
|
float64 fr;
|
|
|
|
fa = s_to_float32(a);
|
|
fr = float32_to_float64(fa, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
uint64_t helper_cvtqs(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float32 fr = int64_to_float32(a, &FP_STATUS);
|
|
return float32_to_s(fr);
|
|
}
|
|
|
|
/* Implement float64 to uint64 conversion without saturation -- we must
|
|
supply the truncated result. This behaviour is used by the compiler
|
|
to get unsigned conversion for free with the same instruction.
|
|
|
|
The VI flag is set when overflow or inexact exceptions should be raised. */
|
|
|
|
static inline uint64_t inline_cvttq(CPUAlphaState *env, uint64_t a,
|
|
int roundmode, int VI)
|
|
{
|
|
uint64_t frac, ret = 0;
|
|
uint32_t exp, sign, exc = 0;
|
|
int shift;
|
|
|
|
sign = (a >> 63);
|
|
exp = (uint32_t)(a >> 52) & 0x7ff;
|
|
frac = a & 0xfffffffffffffull;
|
|
|
|
if (exp == 0) {
|
|
if (unlikely(frac != 0)) {
|
|
goto do_underflow;
|
|
}
|
|
} else if (exp == 0x7ff) {
|
|
exc = (frac ? float_flag_invalid : VI ? float_flag_overflow : 0);
|
|
} else {
|
|
/* Restore implicit bit. */
|
|
frac |= 0x10000000000000ull;
|
|
|
|
shift = exp - 1023 - 52;
|
|
if (shift >= 0) {
|
|
/* In this case the number is so large that we must shift
|
|
the fraction left. There is no rounding to do. */
|
|
if (shift < 63) {
|
|
ret = frac << shift;
|
|
if (VI && (ret >> shift) != frac) {
|
|
exc = float_flag_overflow;
|
|
}
|
|
}
|
|
} else {
|
|
uint64_t round;
|
|
|
|
/* In this case the number is smaller than the fraction as
|
|
represented by the 52 bit number. Here we must think
|
|
about rounding the result. Handle this by shifting the
|
|
fractional part of the number into the high bits of ROUND.
|
|
This will let us efficiently handle round-to-nearest. */
|
|
shift = -shift;
|
|
if (shift < 63) {
|
|
ret = frac >> shift;
|
|
round = frac << (64 - shift);
|
|
} else {
|
|
/* The exponent is so small we shift out everything.
|
|
Leave a sticky bit for proper rounding below. */
|
|
do_underflow:
|
|
round = 1;
|
|
}
|
|
|
|
if (round) {
|
|
exc = (VI ? float_flag_inexact : 0);
|
|
switch (roundmode) {
|
|
case float_round_nearest_even:
|
|
if (round == (1ull << 63)) {
|
|
/* Fraction is exactly 0.5; round to even. */
|
|
ret += (ret & 1);
|
|
} else if (round > (1ull << 63)) {
|
|
ret += 1;
|
|
}
|
|
break;
|
|
case float_round_to_zero:
|
|
break;
|
|
case float_round_up:
|
|
ret += 1 - sign;
|
|
break;
|
|
case float_round_down:
|
|
ret += sign;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (sign) {
|
|
ret = -ret;
|
|
}
|
|
}
|
|
if (unlikely(exc)) {
|
|
float_raise(exc, &FP_STATUS);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
uint64_t helper_cvttq(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
return inline_cvttq(env, a, FP_STATUS.float_rounding_mode, 1);
|
|
}
|
|
|
|
uint64_t helper_cvttq_c(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
return inline_cvttq(env, a, float_round_to_zero, 0);
|
|
}
|
|
|
|
uint64_t helper_cvttq_svic(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
return inline_cvttq(env, a, float_round_to_zero, 1);
|
|
}
|
|
|
|
uint64_t helper_cvtqt(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fr = int64_to_float64(a, &FP_STATUS);
|
|
return float64_to_t(fr);
|
|
}
|
|
|
|
uint64_t helper_cvtqf(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float32 fr = int64_to_float32(a, &FP_STATUS);
|
|
return float32_to_f(fr);
|
|
}
|
|
|
|
uint64_t helper_cvtgf(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fa;
|
|
float32 fr;
|
|
|
|
fa = g_to_float64(env, GETPC(), a);
|
|
fr = float64_to_float32(fa, &FP_STATUS);
|
|
return float32_to_f(fr);
|
|
}
|
|
|
|
uint64_t helper_cvtgq(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fa = g_to_float64(env, GETPC(), a);
|
|
return float64_to_int64_round_to_zero(fa, &FP_STATUS);
|
|
}
|
|
|
|
uint64_t helper_cvtqg(CPUAlphaState *env, uint64_t a)
|
|
{
|
|
float64 fr;
|
|
fr = int64_to_float64(a, &FP_STATUS);
|
|
return float64_to_g(fr);
|
|
}
|