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 20import io 21import re 22 23import sys 24import textwrap 25import iset 26import hex_common 27import argparse 28 29encs = { 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 36regre = re.compile(r"((?<!DUP)[MNORCPQXSGVZA])([stuvwxyzdefg]+)([.]?[LlHh]?)(\d+S?)") 37immre = re.compile(r"[#]([rRsSuUm])(\d+)(?:[:](\d+))?") 38 39 40def ordered_unique(l): 41 return sorted(set(l), key=l.index) 42 43 44def code_fmt(txt): 45 return textwrap.indent(textwrap.dedent(txt), " ") 46 47open_curly = "{" 48close_curly = "}" 49 50def 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## 78def 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 has_pred_dest = "false" 95 for regno, (reg_type, reg_id, *_) in enumerate(regs): 96 reg = hex_common.get_register(tag, reg_type, reg_id) 97 f.write(code_fmt(f"""\ 98 insn->regno[{regno}] = args->{reg_type}{reg_id}; 99 """)) 100 if reg.is_read() and reg.is_new(): 101 new_read_idx = regno 102 if reg.is_written(): 103 # dest_idx should be the first destination alphabetically 104 if dest_idx_reg_id is None or reg_id < dest_idx_reg_id: 105 dest_idx = regno 106 dest_idx_reg_id = reg_id 107 if reg_type == "P" and reg.is_written() and not reg.is_read(): 108 has_pred_dest = "true" 109 110 if len(imms) != 0: 111 mark_which_imm_extended(f, tag) 112 113 for imm in imms: 114 imm_type = imm[0] 115 imm_letter = "i" if imm_type.islower() else "I" 116 immno = 0 if imm_type.islower() else 1 117 imm_shift = int(imm[2]) if imm[2] else 0 118 if imm_shift: 119 f.write(code_fmt(f"""\ 120 insn->immed[{immno}] = 121 shift_left(ctx, args->{imm_type}{imm_letter}, 122 {imm_shift}, {immno}); 123 """)) 124 else: 125 f.write(code_fmt(f"""\ 126 insn->immed[{immno}] = args->{imm_type}{imm_letter}; 127 """)) 128 129 f.write(code_fmt(f"""\ 130 insn->new_read_idx = {new_read_idx}; 131 insn->dest_idx = {dest_idx}; 132 insn->has_pred_dest = {has_pred_dest}; 133 """)) 134 f.write(textwrap.dedent(f"""\ 135 return true; 136 {close_curly} 137 """)) 138 139 140def main(): 141 parser = argparse.ArgumentParser( 142 description="Emit trans_*() functions to be called by " \ 143 "instruction decoder" 144 ) 145 parser.add_argument("semantics", help="semantics file") 146 parser.add_argument("out", help="output file") 147 args = parser.parse_args() 148 hex_common.read_semantics_file(args.semantics) 149 hex_common.init_registers() 150 with open(args.out, "w") as f: 151 gen_trans_funcs(f) 152 153 154if __name__ == "__main__": 155 main() 156