| 1 | #!/usr/bin/env python3 |
| 2 | |
| 3 | ## |
| 4 | ## Copyright (c) 2024 Taylor Simpson <ltaylorsimpson@gmail.com> |
| 5 | ## |
| 6 | ## This program is free software; you can redistribute it and/or modify |
| 7 | ## it under the terms of the GNU General Public License as published by |
| 8 | ## the Free Software Foundation; either version 2 of the License, or |
| 9 | ## (at your option) any later version. |
| 10 | ## |
| 11 | ## This program is distributed in the hope that it will be useful, |
| 12 | ## but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | ## GNU General Public License for more details. |
| 15 | ## |
| 16 | ## You should have received a copy of the GNU General Public License |
| 17 | ## along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 18 | ## |
| 19 | |
| 20 | import io |
| 21 | import re |
| 22 | |
| 23 | import sys |
| 24 | import textwrap |
| 25 | import iset |
| 26 | import hex_common |
| 27 | import argparse |
| 28 | |
| 29 | encs = { |
| 30 | tag: "".join(reversed(iset.iset[tag]["enc"].replace(" ", ""))) |
| 31 | for tag in iset.tags |
| 32 | if iset.iset[tag]["enc"] != "MISSING ENCODING" |
| 33 | } |
| 34 | |
| 35 | |
| 36 | regre = re.compile(r"((?<!DUP)[MNORCPQXSGVZA])([stuvwxyzdefg]+)([.]?[LlHh]?)(\d+S?)") |
| 37 | immre = re.compile(r"[#]([rRsSuUm])(\d+)(?:[:](\d+))?") |
| 38 | |
| 39 | |
| 40 | def ordered_unique(l): |
| 41 | return sorted(set(l), key=l.index) |
| 42 | |
| 43 | |
| 44 | def code_fmt(txt): |
| 45 | return textwrap.indent(textwrap.dedent(txt), " ") |
| 46 | |
| 47 | open_curly = "{" |
| 48 | close_curly = "}" |
| 49 | |
| 50 | def mark_which_imm_extended(f, tag): |
| 51 | immre = re.compile(r"IMMEXT\([rRsSuUm]") |
| 52 | imm = immre.findall(hex_common.semdict[tag]) |
| 53 | if len(imm) == 0: |
| 54 | # No extended operand found |
| 55 | return |
| 56 | letter = re.split("\\(", imm[0])[1] |
| 57 | f.write(code_fmt(f"""\ |
| 58 | insn->which_extended = {0 if letter.islower() else 1}; |
| 59 | """)) |
| 60 | |
| 61 | ## |
| 62 | ## Generate the QEMU decodetree trans_<tag> function for each instruction |
| 63 | ## For A2_add: Rd32=add(Rs32,Rt32) |
| 64 | ## We produce: |
| 65 | ## static bool trans_A2_add(DisasContext *ctx, arg_A2_add *args) |
| 66 | ## { |
| 67 | ## Insn *insn = ctx->insn; |
| 68 | ## insn->opcode = A2_add; |
| 69 | ## insn->regno[0] = args->Rd; |
| 70 | ## insn->regno[1] = args->Rs; |
| 71 | ## insn->regno[2] = args->Rt; |
| 72 | ## insn->new_read_idx = -1; |
| 73 | ## insn->dest_idx = 0; |
| 74 | ## insn->has_pred_dest = false; |
| 75 | ## return true; |
| 76 | ## } |
| 77 | ## |
| 78 | def gen_trans_funcs(f): |
| 79 | f.write(f"/* DO NOT MODIFY - This file is generated by {sys.argv[0]} */\n\n") |
| 80 | for tag in sorted(encs.keys(), key=iset.tags.index): |
| 81 | regs = ordered_unique(regre.findall(iset.iset[tag]["syntax"])) |
| 82 | imms = ordered_unique(immre.findall(iset.iset[tag]["syntax"])) |
| 83 | |
| 84 | f.write(textwrap.dedent(f"""\ |
| 85 | static bool trans_{tag}(DisasContext *ctx, arg_{tag} *args) |
| 86 | {open_curly} |
| 87 | Insn *insn = ctx->insn; |
| 88 | insn->opcode = {tag}; |
| 89 | """)) |
| 90 | |
| 91 | new_read_idx = -1 |
| 92 | dest_idx = -1 |
| 93 | dest_idx_reg_id = None |
| 94 | dest_is_pair = "false" |
| 95 | dest_is_gpr = "false" |
| 96 | has_pred_dest = "false" |
| 97 | for regno, (reg_type, reg_id, *_) in enumerate(regs): |
| 98 | reg = hex_common.get_register(tag, reg_type, reg_id) |
| 99 | f.write(code_fmt(f"""\ |
| 100 | insn->regno[{regno}] = args->{reg_type}{reg_id}; |
| 101 | """)) |
| 102 | if reg.is_read() and reg.is_new(): |
| 103 | new_read_idx = regno |
| 104 | if reg.is_written(): |
| 105 | # dest_idx should be the first destination alphabetically |
| 106 | if dest_idx_reg_id is None or reg_id < dest_idx_reg_id: |
| 107 | dest_idx = regno |
| 108 | dest_idx_reg_id = reg_id |
| 109 | dest_is_pair = ("true" |
| 110 | if isinstance(reg, hex_common.Pair) |
| 111 | else "false") |
| 112 | dest_is_gpr = ("true" |
| 113 | if reg_type == "R" |
| 114 | else "false") |
| 115 | if reg_type == "P" and reg.is_written() and not reg.is_read(): |
| 116 | has_pred_dest = "true" |
| 117 | |
| 118 | if len(imms) != 0: |
| 119 | mark_which_imm_extended(f, tag) |
| 120 | |
| 121 | for imm in imms: |
| 122 | imm_type = imm[0] |
| 123 | imm_letter = "i" if imm_type.islower() else "I" |
| 124 | immno = 0 if imm_type.islower() else 1 |
| 125 | imm_shift = int(imm[2]) if imm[2] else 0 |
| 126 | if imm_shift: |
| 127 | f.write(code_fmt(f"""\ |
| 128 | insn->immed[{immno}] = |
| 129 | shift_left(ctx, args->{imm_type}{imm_letter}, |
| 130 | {imm_shift}, {immno}); |
| 131 | """)) |
| 132 | else: |
| 133 | f.write(code_fmt(f"""\ |
| 134 | insn->immed[{immno}] = args->{imm_type}{imm_letter}; |
| 135 | """)) |
| 136 | |
| 137 | f.write(code_fmt(f"""\ |
| 138 | insn->new_read_idx = {new_read_idx}; |
| 139 | insn->dest_idx = {dest_idx}; |
| 140 | insn->dest_is_pair = {dest_is_pair}; |
| 141 | insn->dest_is_gpr = {dest_is_gpr}; |
| 142 | insn->has_pred_dest = {has_pred_dest}; |
| 143 | """)) |
| 144 | f.write(textwrap.dedent(f"""\ |
| 145 | return true; |
| 146 | {close_curly} |
| 147 | """)) |
| 148 | |
| 149 | |
| 150 | def main(): |
| 151 | parser = argparse.ArgumentParser( |
| 152 | description="Emit trans_*() functions to be called by " \ |
| 153 | "instruction decoder" |
| 154 | ) |
| 155 | parser.add_argument("semantics", help="semantics file") |
| 156 | parser.add_argument("out", help="output file") |
| 157 | args = parser.parse_args() |
| 158 | hex_common.read_semantics_file(args.semantics) |
| 159 | hex_common.init_registers() |
| 160 | with open(args.out, "w") as f: |
| 161 | gen_trans_funcs(f) |
| 162 | |
| 163 | |
| 164 | if __name__ == "__main__": |
| 165 | main() |