| /* xgate-dis.c -- Freescale XGATE disassembly |
| Copyright (C) 2009-2025 Free Software Foundation, Inc. |
| Written by Sean Keys (skeys@ipdatasys.com) |
| |
| This file is part of the GNU opcodes library. |
| |
| This library 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 3, or (at your option) |
| any later version. |
| |
| It 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, write to the Free Software |
| Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| #include "sysdep.h" |
| #include <assert.h> |
| #include "disassemble.h" |
| #include "opintl.h" |
| #include "libiberty.h" |
| #include "ansidecl.h" |
| #include "opcode/xgate.h" |
| |
| #define XGATE_TWO_BYTES 0x02 |
| #define XGATE_NINE_BITS 0x1FF |
| #define XGATE_TEN_BITS 0x3FF |
| #define XGATE_NINE_SIGNBIT 0x100 |
| #define XGATE_TEN_SIGNBIT 0x200 |
| |
| /* Structures. */ |
| struct decodeInfo |
| { |
| unsigned int operMask; |
| unsigned int operMasksRegisterBits; |
| struct xgate_opcode *opcodePTR; |
| }; |
| |
| /* Prototypes for local functions. */ |
| static int print_insn (bfd_vma, struct disassemble_info *); |
| static int read_memory (bfd_vma, bfd_byte*, int, struct disassemble_info *); |
| static int ripBits (unsigned int *, int, |
| struct xgate_opcode *, unsigned int); |
| static int macro_search (char *, char *); |
| static struct decodeInfo * find_match (unsigned int); |
| |
| /* Statics. */ |
| static struct decodeInfo *decodeTable; |
| static int initialized; |
| static char previousOpName[10]; |
| static unsigned int perviousBin; |
| |
| /* Disassemble one instruction at address 'memaddr'. Returns the number |
| of bytes used by that instruction. */ |
| |
| static int |
| print_insn (bfd_vma memaddr, struct disassemble_info* info) |
| { |
| int status; |
| unsigned int raw_code; |
| char *s = 0; |
| long bytesRead = 0; |
| int i = 0; |
| struct xgate_opcode *opcodePTR = (struct xgate_opcode*) xgate_opcodes; |
| struct decodeInfo *decodeTablePTR = 0; |
| struct decodeInfo *decodePTR = 0; |
| unsigned int operandRegisterBits = 0; |
| signed int relAddr = 0; |
| signed int operandOne = 0; |
| signed int operandTwo = 0; |
| bfd_byte buffer[4]; |
| bfd_vma absAddress; |
| |
| unsigned int operMaskReg = 0; |
| /* Initialize our array of opcode masks and check them against our constant |
| table. */ |
| if (!initialized) |
| { |
| decodeTable = xmalloc (sizeof (struct decodeInfo) * xgate_num_opcodes); |
| for (i = 0, decodeTablePTR = decodeTable; i < xgate_num_opcodes; |
| i++, decodeTablePTR++, opcodePTR++) |
| { |
| unsigned int bin = 0; |
| unsigned int mask = 0; |
| for (s = opcodePTR->format; *s; s++) |
| { |
| bin <<= 1; |
| mask <<= 1; |
| operandRegisterBits <<= 1; |
| bin |= (*s == '1'); |
| mask |= (*s == '0' || *s == '1'); |
| operandRegisterBits |= (*s == 'r'); |
| } |
| /* Asserting will uncover inconsistencies in our table. */ |
| assert ((s - opcodePTR->format) == 16 || (s - opcodePTR->format) == 32); |
| assert (opcodePTR->bin_opcode == bin); |
| |
| decodeTablePTR->operMask = mask; |
| decodeTablePTR->operMasksRegisterBits = operandRegisterBits; |
| decodeTablePTR->opcodePTR = opcodePTR; |
| } |
| initialized = 1; |
| } |
| |
| /* Read 16 bits. */ |
| bytesRead += XGATE_TWO_BYTES; |
| status = read_memory (memaddr, buffer, XGATE_TWO_BYTES, info); |
| if (status == 0) |
| { |
| raw_code = buffer[0]; |
| raw_code <<= 8; |
| raw_code += buffer[1]; |
| |
| decodePTR = find_match (raw_code); |
| if (decodePTR) |
| { |
| operMaskReg = decodePTR->operMasksRegisterBits; |
| (*info->fprintf_func)(info->stream, "%s", decodePTR->opcodePTR->name); |
| |
| /* First we compare the shorthand format of the constraints. If we |
| still are unable to pinpoint the operands |
| we analyze the opcodes constraint string. */ |
| if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_MON_R_C)) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, CCR", |
| (raw_code >> 8) & 0x7); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_MON_C_R)) |
| { |
| (*info->fprintf_func)(info->stream, " CCR, R%x", |
| (raw_code >> 8) & 0x7); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_MON_R_P)) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, PC", |
| (raw_code >> 8) & 0x7); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_TRI)) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, R%x, R%x", |
| (raw_code >> 8) & 0x7, (raw_code >> 5) & 0x7, |
| (raw_code >> 2) & 0x7); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_IDR)) |
| { |
| if (raw_code & 0x01) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, (R%x, R%x+)", |
| (raw_code >> 8) & 0x7, (raw_code >> 5) & 0x7, |
| (raw_code >> 2) & 0x7); |
| } |
| else if (raw_code & 0x02) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, (R%x, -R%x)", |
| (raw_code >> 8) & 0x7, (raw_code >> 5) & 0x7, |
| (raw_code >> 2) & 0x7); |
| } |
| else |
| { |
| (*info->fprintf_func)(info->stream, " R%x, (R%x, R%x)", |
| (raw_code >> 8) & 0x7, (raw_code >> 5) & 0x7, |
| (raw_code >> 2) & 0x7); |
| } |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_DYA)) |
| { |
| operandOne = ripBits (&operMaskReg, 3, decodePTR->opcodePTR, raw_code); |
| operandTwo = ripBits (&operMaskReg, 3, decodePTR->opcodePTR, raw_code); |
| ( *info->fprintf_func)(info->stream, " R%x, R%x", operandOne, |
| operandTwo); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_IDO5)) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, (R%x, #0x%x)", |
| (raw_code >> 8) & 0x7, (raw_code >> 5) & 0x7, raw_code & 0x1f); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_MON)) |
| { |
| operandOne = ripBits (&operMaskReg, 3, decodePTR->opcodePTR, |
| raw_code); |
| (*info->fprintf_func)(info->stream, " R%x", operandOne); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_REL9)) |
| { |
| /* If address is negative handle it accordingly. */ |
| if (raw_code & XGATE_NINE_SIGNBIT) |
| { |
| relAddr = XGATE_NINE_BITS >> 1; /* Clip sign bit. */ |
| relAddr = ~relAddr; /* Make signed. */ |
| relAddr |= (raw_code & 0xFF) + 1; /* Apply our value. */ |
| relAddr *= 2; /* Multiply by two as per processor docs. */ |
| } |
| else |
| { |
| relAddr = raw_code & 0xff; |
| relAddr = relAddr * 2 + 2; |
| } |
| (*info->fprintf_func)(info->stream, " *%d", relAddr); |
| (*info->fprintf_func)(info->stream, " Abs* 0x"); |
| (*info->print_address_func)(memaddr + relAddr, info); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_REL10)) |
| { |
| /* If address is negative handle it accordingly. */ |
| if (raw_code & XGATE_TEN_SIGNBIT) |
| { |
| relAddr = XGATE_TEN_BITS >> 1; /* Clip sign bit. */ |
| relAddr = ~relAddr; /* Make signed. */ |
| relAddr |= (raw_code & 0x1FF) + 1; /* Apply our value. */ |
| relAddr *= 2; /* Multiply by two as per processor docs. */ |
| } |
| else |
| { |
| relAddr = raw_code & 0x1FF; |
| relAddr = relAddr * 2 + 2; |
| } |
| (*info->fprintf_func)(info->stream, " *%d", relAddr); |
| (*info->fprintf_func)(info->stream, " Abs* 0x"); |
| (*info->print_address_func)(memaddr + relAddr, info); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_IMM4)) |
| { |
| (*info->fprintf_func)(info->stream, " R%x, #0x%02x", |
| (raw_code >> 8) & 0x7, (raw_code >> 4) & 0xF); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_IMM8)) |
| { |
| if (macro_search (decodePTR->opcodePTR->name, previousOpName) && |
| previousOpName[0]) |
| { |
| absAddress = (0xFF & raw_code) << 8; |
| absAddress |= perviousBin & 0xFF; |
| (*info->fprintf_func)(info->stream, " R%x, #0x%02x Abs* 0x", |
| (raw_code >> 8) & 0x7, raw_code & 0xff); |
| (*info->print_address_func)(absAddress, info); |
| previousOpName[0] = 0; |
| } |
| else |
| { |
| strcpy (previousOpName, decodePTR->opcodePTR->name); |
| (*info->fprintf_func)(info->stream, " R%x, #0x%02x", |
| (raw_code >> 8) & 0x7, raw_code & 0xff); |
| } |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_IMM3)) |
| { |
| (*info->fprintf_func)(info->stream, " #0x%x", |
| (raw_code >> 8) & 0x7); |
| } |
| else if (!strcmp (decodePTR->opcodePTR->constraints, XGATE_OP_INH)) |
| { |
| } |
| else |
| { |
| (*info->fprintf_func)(info->stream, " unhandled mode %s", |
| decodePTR->opcodePTR->constraints); |
| } |
| perviousBin = raw_code; |
| } |
| else |
| { |
| (*info->fprintf_func)(info->stream, |
| " unable to find opcode match #0%x", raw_code); |
| } |
| } |
| return bytesRead; |
| } |
| |
| int |
| print_insn_xgate (bfd_vma memaddr, struct disassemble_info* info) |
| { |
| return print_insn (memaddr, info); |
| } |
| |
| static int |
| read_memory (bfd_vma memaddr, bfd_byte* buffer, int size, |
| struct disassemble_info* info) |
| { |
| int status; |
| status = (*info->read_memory_func) (memaddr, buffer, size, info); |
| if (status != 0) |
| { |
| (*info->memory_error_func) (status, memaddr, info); |
| return -1; |
| } |
| return 0; |
| } |
| |
| static int |
| ripBits (unsigned int *operandBitsRemaining, |
| int numBitsRequested, |
| struct xgate_opcode *opcodePTR, |
| unsigned int memory) |
| { |
| unsigned int currentBit; |
| unsigned int operand = 0; |
| int numBitsFound; |
| |
| for (numBitsFound = 0, currentBit = 1u << ((opcodePTR->size * 8) - 1); |
| numBitsFound < numBitsRequested && currentBit != 0; |
| currentBit >>= 1) |
| { |
| if (currentBit & *operandBitsRemaining) |
| { |
| *operandBitsRemaining &= ~(currentBit); /* Consume the current bit. */ |
| operand <<= 1; /* Make room for our next bit. */ |
| numBitsFound++; |
| operand |= (currentBit & memory) > 0; |
| } |
| } |
| return operand; |
| } |
| |
| static int |
| macro_search (char *currentName, char *lastName) |
| { |
| int i; |
| int length = 0; |
| char *where; |
| |
| for (i = 0; i < xgate_num_opcodes; i++) |
| { |
| where = strstr (xgate_opcodes[i].constraints, lastName); |
| |
| if (where) |
| { |
| length = strlen (where); |
| } |
| if (length) |
| { |
| where = strstr (xgate_opcodes[i].constraints, currentName); |
| if (where) |
| { |
| length = strlen (where); |
| return 1; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| static struct decodeInfo * |
| find_match (unsigned int raw_code) |
| { |
| struct decodeInfo *decodeTablePTR = 0; |
| int i; |
| |
| for (i = 0, decodeTablePTR = decodeTable; i < xgate_num_opcodes; |
| i++, decodeTablePTR++) |
| { |
| if ((raw_code & decodeTablePTR->operMask) |
| == decodeTablePTR->opcodePTR->bin_opcode) |
| { |
| /* Make sure we didn't run into a macro or alias. */ |
| if (decodeTablePTR->opcodePTR->cycles_min != 0) |
| { |
| return decodeTablePTR; |
| break; |
| } |
| else |
| continue; |
| } |
| } |
| return 0; |
| } |
