qemu-e2k/target/hexagon/gen_trans_funcs.py
Taylor Simpson f6c01009b5 Hexagon (target/hexagon) Use QEMU decodetree (16-bit instructions)
Section 10.3 of the Hexagon V73 Programmer's Reference Manual

A duplex is encoded as a 32-bit instruction with bits [15:14] set to 00.
The sub-instructions that comprise a duplex are encoded as 13-bit fields
in the duplex.

Create a decoder for each subinstruction class (a, l1, l2, s1, s2).

Extend gen_trans_funcs.py to handle all instructions rather than
filter by instruction class.

There is a g_assert_not_reached() in decode_insns() in decode.c to
verify we never try to use the old decoder on 16-bit instructions.

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240115221443.365287-3-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
2024-01-21 22:02:40 -08:00

125 lines
3.7 KiB
Python
Executable File

#!/usr/bin/env python3
##
## Copyright (c) 2024 Taylor Simpson <ltaylorsimpson@gmail.com>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This program 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 General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
import io
import re
import sys
import textwrap
import iset
import hex_common
encs = {
tag: "".join(reversed(iset.iset[tag]["enc"].replace(" ", "")))
for tag in iset.tags
if iset.iset[tag]["enc"] != "MISSING ENCODING"
}
regre = re.compile(r"((?<!DUP)[MNORCPQXSGVZA])([stuvwxyzdefg]+)([.]?[LlHh]?)(\d+S?)")
immre = re.compile(r"[#]([rRsSuUm])(\d+)(?:[:](\d+))?")
def ordered_unique(l):
return sorted(set(l), key=l.index)
def code_fmt(txt):
return textwrap.indent(textwrap.dedent(txt), " ")
open_curly = "{"
close_curly = "}"
def mark_which_imm_extended(f, tag):
immre = re.compile(r"IMMEXT\([rRsSuUm]")
imm = immre.findall(hex_common.semdict[tag])
if len(imm) == 0:
# No extended operand found
return
letter = re.split("\\(", imm[0])[1]
f.write(code_fmt(f"""\
insn->which_extended = {0 if letter.islower() else 1};
"""))
##
## Generate the QEMU decodetree trans_<tag> function for each instruction
## For A2_add: Rd32=add(Rs32,Rt32)
## We produce:
## static bool trans_A2_add(DisasContext *ctx, arg_A2_add *args)
## {
## Insn *insn = ctx->insn;
## insn->opcode = A2_add;
## insn->regno[0] = args->Rd;
## insn->regno[1] = args->Rs;
## insn->regno[2] = args->Rt;
## return true;
## }
##
def gen_trans_funcs(f):
f.write(f"/* DO NOT MODIFY - This file is generated by {sys.argv[0]} */\n\n")
for tag in sorted(encs.keys(), key=iset.tags.index):
regs = ordered_unique(regre.findall(iset.iset[tag]["syntax"]))
imms = ordered_unique(immre.findall(iset.iset[tag]["syntax"]))
f.write(textwrap.dedent(f"""\
static bool trans_{tag}(DisasContext *ctx, arg_{tag} *args)
{open_curly}
Insn *insn = ctx->insn;
insn->opcode = {tag};
"""))
regno = 0
for reg in regs:
reg_type = reg[0]
reg_id = reg[1]
f.write(code_fmt(f"""\
insn->regno[{regno}] = args->{reg_type}{reg_id};
"""))
regno += 1
if len(imms) != 0:
mark_which_imm_extended(f, tag)
for imm in imms:
imm_type = imm[0]
imm_letter = "i" if imm_type.islower() else "I"
immno = 0 if imm_type.islower() else 1
imm_shift = int(imm[2]) if imm[2] else 0
if imm_shift:
f.write(code_fmt(f"""\
insn->immed[{immno}] =
shift_left(ctx, args->{imm_type}{imm_letter},
{imm_shift}, {immno});
"""))
else:
f.write(code_fmt(f"""\
insn->immed[{immno}] = args->{imm_type}{imm_letter};
"""))
f.write(textwrap.dedent(f"""\
return true;
{close_curly}
"""))
if __name__ == "__main__":
hex_common.read_semantics_file(sys.argv[1])
with open(sys.argv[2], "w") as f:
gen_trans_funcs(f)