mirror of https://gitlab.com/qemu-project/qemu
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
78 lines
2.6 KiB
C
78 lines
2.6 KiB
C
/*
|
|
* MIPS SIMD Architecture Module Instruction emulation helpers for QEMU.
|
|
*
|
|
* Copyright (c) 2014 Imagination Technologies
|
|
*
|
|
* 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 "internal.h"
|
|
#include "fpu/softfloat.h"
|
|
#include "fpu_helper.h"
|
|
|
|
void msa_reset(CPUMIPSState *env)
|
|
{
|
|
if (!ase_msa_available(env)) {
|
|
return;
|
|
}
|
|
|
|
#ifdef CONFIG_USER_ONLY
|
|
/* MSA access enabled */
|
|
env->CP0_Config5 |= 1 << CP0C5_MSAEn;
|
|
env->CP0_Status |= (1 << CP0St_CU1) | (1 << CP0St_FR);
|
|
#endif
|
|
|
|
/*
|
|
* MSA CSR:
|
|
* - non-signaling floating point exception mode off (NX bit is 0)
|
|
* - Cause, Enables, and Flags are all 0
|
|
* - round to nearest / ties to even (RM bits are 0)
|
|
*/
|
|
env->active_tc.msacsr = 0;
|
|
|
|
restore_msa_fp_status(env);
|
|
|
|
/* tininess detected after rounding.*/
|
|
set_float_detect_tininess(float_tininess_after_rounding,
|
|
&env->active_tc.msa_fp_status);
|
|
|
|
/*
|
|
* According to MIPS specifications, if one of the two operands is
|
|
* a sNaN, a new qNaN has to be generated. This is done in
|
|
* floatXX_silence_nan(). For qNaN inputs the specifications
|
|
* says: "When possible, this QNaN result is one of the operand QNaN
|
|
* values." In practice it seems that most implementations choose
|
|
* the first operand if both operands are qNaN. In short this gives
|
|
* the following rules:
|
|
* 1. A if it is signaling
|
|
* 2. B if it is signaling
|
|
* 3. A (quiet)
|
|
* 4. B (quiet)
|
|
* A signaling NaN is always silenced before returning it.
|
|
*/
|
|
set_float_2nan_prop_rule(float_2nan_prop_s_ab,
|
|
&env->active_tc.msa_fp_status);
|
|
|
|
/* clear float_status exception flags */
|
|
set_float_exception_flags(0, &env->active_tc.msa_fp_status);
|
|
|
|
/* clear float_status nan mode */
|
|
set_default_nan_mode(0, &env->active_tc.msa_fp_status);
|
|
|
|
/* set proper signanling bit meaning ("1" means "quiet") */
|
|
set_snan_bit_is_one(0, &env->active_tc.msa_fp_status);
|
|
}
|