/*
* ARM translation: AArch32 VFP instructions
*
* Copyright (c) 2003 Fabrice Bellard
* Copyright (c) 2005-2007 CodeSourcery
* Copyright (c) 2007 OpenedHand, Ltd.
* Copyright (c) 2019 Linaro, Ltd.
*
* 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/>.
*/
/*
* This file is intended to be included from translate.c; it uses
* some macros and definitions provided by that file.
* It might be possible to convert it to a standalone .c file eventually.
*/
/* Include the generated VFP decoder */
#include "decode-vfp.inc.c"
#include "decode-vfp-uncond.inc.c"
/*
* Check that VFP access is enabled. If it is, do the necessary
* M-profile lazy-FP handling and then return true.
* If not, emit code to generate an appropriate exception and
* return false.
* The ignore_vfp_enabled argument specifies that we should ignore
* whether VFP is enabled via FPEXC[EN]: this should be true for FMXR/FMRX
* accesses to FPSID, FPEXC, MVFR0, MVFR1, MVFR2, and false for all other insns.
*/
static bool full_vfp_access_check(DisasContext *s, bool ignore_vfp_enabled)
{
if (s->fp_excp_el) {
if (arm_dc_feature(s, ARM_FEATURE_M)) {
gen_exception_insn(s, 4, EXCP_NOCP, syn_uncategorized(),
s->fp_excp_el);
} else {
gen_exception_insn(s, 4, EXCP_UDEF,
syn_fp_access_trap(1, 0xe, false),
s->fp_excp_el);
}
return false;
}
if (!s->vfp_enabled && !ignore_vfp_enabled) {
assert(!arm_dc_feature(s, ARM_FEATURE_M));
gen_exception_insn(s, 4, EXCP_UDEF, syn_uncategorized(),
default_exception_el(s));
return false;
}
if (arm_dc_feature(s, ARM_FEATURE_M)) {
/* Handle M-profile lazy FP state mechanics */
/* Trigger lazy-state preservation if necessary */
if (s->v7m_lspact) {
/*
* Lazy state saving affects external memory and also the NVIC,
* so we must mark it as an IO operation for icount.
*/
if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
gen_io_start();
}
gen_helper_v7m_preserve_fp_state(cpu_env);
if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
gen_io_end();
}
/*
* If the preserve_fp_state helper doesn't throw an exception
* then it will clear LSPACT; we don't need to repeat this for
* any further FP insns in this TB.
*/
s->v7m_lspact = false;
}
/* Update ownership of FP context: set FPCCR.S to match current state */
if (s->v8m_fpccr_s_wrong) {
TCGv_i32 tmp;
tmp = load_cpu_field(v7m.fpccr[M_REG_S]);
if (s->v8m_secure) {
tcg_gen_ori_i32(tmp, tmp, R_V7M_FPCCR_S_MASK);
} else {
tcg_gen_andi_i32(tmp, tmp, ~R_V7M_FPCCR_S_MASK);
}
store_cpu_field(tmp, v7m.fpccr[M_REG_S]);
/* Don't need to do this for any further FP insns in this TB */
s->v8m_fpccr_s_wrong = false;
}
if (s->v7m_new_fp_ctxt_needed) {
/*
* Create new FP context by updating CONTROL.FPCA, CONTROL.SFPA
* and the FPSCR.
*/
TCGv_i32 control, fpscr;
uint32_t bits = R_V7M_CONTROL_FPCA_MASK;
fpscr = load_cpu_field(v7m.fpdscr[s->v8m_secure]);
gen_helper_vfp_set_fpscr(cpu_env, fpscr);
tcg_temp_free_i32(fpscr);
/*
* We don't need to arrange to end the TB, because the only
* parts of FPSCR which we cache in the TB flags are the VECLEN
* and VECSTRIDE, and those don't exist for M-profile.
*/
if (s->v8m_secure) {
bits |= R_V7M_CONTROL_SFPA_MASK;
}
control = load_cpu_field(v7m.control[M_REG_S]);
tcg_gen_ori_i32(control, control, bits);
store_cpu_field(control, v7m.control[M_REG_S]);
/* Don't need to do this for any further FP insns in this TB */
s->v7m_new_fp_ctxt_needed = false;
}
}
return true;
}
