unicorn/qemu/target/arm/vfp-uncond.decode
Peter Maydell eae621098d target/arm: Implement VFP fp16 for VFP_BINOP operations
Implmeent VFP fp16 support for simple binary-operator VFP insns VADD,
VSUB, VMUL, VDIV, VMINNM and VMAXNM:

* make the VFP_BINOP() macro generate float16 helpers as well as
float32 and float64
* implement a do_vfp_3op_hp() function similar to the existing
do_vfp_3op_sp()
* add decode for the half-precision insn patterns

Note that the VFP_BINOP macro use creates a couple of unused helper
functions vfp_maxh and vfp_minh, but they're small so it's not worth
splitting the BINOP operations into "needs halfprec" and "no
halfprec" groups.

Backports commit 120a0eb3ea23a5b06fae2f3daebd46a4035864cf
2021-02-28 04:24:39 -05:00

71 lines
2.8 KiB
Plaintext

# AArch32 VFP instruction descriptions (unconditional insns)
#
# 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 processed by scripts/decodetree.py
#
# Encodings for the unconditional VFP instructions are here:
# generally anything matching A32
# 1111 1110 .... .... .... 101. ...0 ....
# and T32
# 1111 110. .... .... .... 101. .... ....
# 1111 1110 .... .... .... 101. .... ....
# (but those patterns might also cover some Neon instructions,
# which do not live in this file.)
# VFP registers have an odd encoding with a four-bit field
# and a one-bit field which are assembled in different orders
# depending on whether the register is double or single precision.
# Each individual instruction function must do the checks for
# "double register selected but CPU does not have double support"
# and "double register number has bit 4 set but CPU does not
# support D16-D31" (which should UNDEF).
%vm_dp 5:1 0:4
%vm_sp 0:4 5:1
%vn_dp 7:1 16:4
%vn_sp 16:4 7:1
%vd_dp 22:1 12:4
%vd_sp 12:4 22:1
@vfp_dnm_s ................................ vm=%vm_sp vn=%vn_sp vd=%vd_sp
@vfp_dnm_d ................................ vm=%vm_dp vn=%vn_dp vd=%vd_dp
VSEL 1111 1110 0. cc:2 .... .... 1010 .0.0 .... \
vm=%vm_sp vn=%vn_sp vd=%vd_sp dp=0
VSEL 1111 1110 0. cc:2 .... .... 1011 .0.0 .... \
vm=%vm_dp vn=%vn_dp vd=%vd_dp dp=1
VMAXNM_hp 1111 1110 1.00 .... .... 1001 .0.0 .... @vfp_dnm_s
VMINNM_hp 1111 1110 1.00 .... .... 1001 .1.0 .... @vfp_dnm_s
VMAXNM_sp 1111 1110 1.00 .... .... 1010 .0.0 .... @vfp_dnm_s
VMINNM_sp 1111 1110 1.00 .... .... 1010 .1.0 .... @vfp_dnm_s
VMAXNM_dp 1111 1110 1.00 .... .... 1011 .0.0 .... @vfp_dnm_d
VMINNM_dp 1111 1110 1.00 .... .... 1011 .1.0 .... @vfp_dnm_d
VRINT 1111 1110 1.11 10 rm:2 .... 1010 01.0 .... \
vm=%vm_sp vd=%vd_sp dp=0
VRINT 1111 1110 1.11 10 rm:2 .... 1011 01.0 .... \
vm=%vm_dp vd=%vd_dp dp=1
# VCVT float to int with specified rounding mode; Vd is always single-precision
VCVT 1111 1110 1.11 11 rm:2 .... 1010 op:1 1.0 .... \
vm=%vm_sp vd=%vd_sp dp=0
VCVT 1111 1110 1.11 11 rm:2 .... 1011 op:1 1.0 .... \
vm=%vm_dp vd=%vd_sp dp=1