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qemu/target/arm/vfp-uncond.decode

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target/arm: Add stubs for AArch32 VFP decodetree Add the infrastructure for building and invoking a decodetree decoder for the AArch32 VFP encodings. At the moment the new decoder covers nothing, so we always fall back to the existing hand-written decode. We need to have one decoder for the unconditional insns and one for the conditional insns, as otherwise the patterns for conditional insns would incorrectly match against the unconditional ones too. Since translate.c is over 14,000 lines long and we're going to be touching pretty much every line of the VFP code as part of the decodetree conversion, we create a new translate-vfp.inc.c to hold the code which deals with VFP in the new scheme. It should be possible to convert this into a standalone translation unit eventually, but the conversion process will be much simpler if we simply #include it midway through translate.c to start with. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 18:39:41 +03:00
# 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.)
target/arm: Convert the VSEL instructions to decodetree Convert the VSEL instructions to decodetree. We leave trans_VSEL() in translate.c for now as this allows the patch to show just the changes from the old handle_vsel(). In the old code the check for "do D16-D31 exist" was hidden in the VFP_DREG macro, and assumed that VFPv3 always implied that D16-D31 exist. In the new code we do the correct ID register test. This gives identical behaviour for most of our CPUs, and fixes previously incorrect handling for Cortex-R5F, Cortex-M4 and Cortex-M33, which all implement VFPv3 or better with only 16 double-precision registers. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 18:39:42 +03:00
# 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
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
target/arm: Convert VMINNM, VMAXNM to decodetree Convert the VMINNM and VMAXNM instructions to decodetree. As with VSEL, we leave the trans_VMINMAXNM() function in translate.c for the moment. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 18:39:43 +03:00
VMINMAXNM 1111 1110 1.00 .... .... 1010 . op:1 .0 .... \
vm=%vm_sp vn=%vn_sp vd=%vd_sp dp=0
VMINMAXNM 1111 1110 1.00 .... .... 1011 . op:1 .0 .... \
vm=%vm_dp vn=%vn_dp vd=%vd_dp dp=1
target/arm: Convert VRINTA/VRINTN/VRINTP/VRINTM to decodetree Convert the VRINTA/VRINTN/VRINTP/VRINTM instructions to decodetree. Again, trans_VRINT() is temporarily left in translate.c. Signed-off-by: Peter Maydell <peter.maydell@linaro.org>Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 18:39:43 +03:00
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
target/arm: Convert VCVTA/VCVTN/VCVTP/VCVTM to decodetree Convert the VCVTA/VCVTN/VCVTP/VCVTM instructions to decodetree. trans_VCVT() is temporarily left in translate.c. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 18:39:43 +03:00
# 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
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