Yasm Assembler mainline development tree (ffmpeg 依赖)
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/*
* LC-3b bytecode utility functions
*
* Copyright (C) 2003 Peter Johnson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND OTHER CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR OTHER CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <util.h>
/*@unused@*/ RCSID("$Id$");
#define YASM_LIB_INTERNAL
#define YASM_BC_INTERNAL
#include <libyasm.h>
#include "lc3barch.h"
/* Bytecode callback function prototypes */
static void lc3b_bc_insn_destroy(void *contents);
static void lc3b_bc_insn_print(const void *contents, FILE *f,
int indent_level);
static yasm_bc_resolve_flags lc3b_bc_insn_resolve
(yasm_bytecode *bc, int save, yasm_calc_bc_dist_func calc_bc_dist);
static int lc3b_bc_insn_tobytes(yasm_bytecode *bc, unsigned char **bufp,
void *d, yasm_output_expr_func output_expr,
/*@null@*/ yasm_output_reloc_func output_reloc);
/* Bytecode callback structures */
static const yasm_bytecode_callback lc3b_bc_callback_insn = {
lc3b_bc_insn_destroy,
lc3b_bc_insn_print,
yasm_bc_finalize_common,
lc3b_bc_insn_resolve,
lc3b_bc_insn_tobytes
};
void
yasm_lc3b__bc_transform_insn(yasm_bytecode *bc, lc3b_insn *insn)
{
yasm_bc_transform(bc, &lc3b_bc_callback_insn, insn);
}
static void
lc3b_bc_insn_destroy(void *contents)
{
lc3b_insn *insn = (lc3b_insn *)contents;
if (insn->imm)
yasm_expr_destroy(insn->imm);
yasm_xfree(contents);
}
static void
lc3b_bc_insn_print(const void *contents, FILE *f, int indent_level)
{
const lc3b_insn *insn = (const lc3b_insn *)contents;
fprintf(f, "%*s_Instruction_\n", indent_level, "");
fprintf(f, "%*sImmediate Value:", indent_level, "");
if (!insn->imm)
fprintf(f, " (nil)\n");
else {
indent_level++;
fprintf(f, "\n%*sVal=", indent_level, "");
yasm_expr_print(insn->imm, f);
fprintf(f, "\n%*sType=", indent_level, "");
switch (insn->imm_type) {
case LC3B_IMM_NONE:
fprintf(f, "NONE-SHOULDN'T HAPPEN");
break;
case LC3B_IMM_4:
fprintf(f, "4-bit");
break;
case LC3B_IMM_5:
fprintf(f, "5-bit");
break;
case LC3B_IMM_6_WORD:
fprintf(f, "6-bit, word-multiple");
break;
case LC3B_IMM_6_BYTE:
fprintf(f, "6-bit, byte-multiple");
break;
case LC3B_IMM_8:
fprintf(f, "8-bit, word-multiple");
break;
case LC3B_IMM_9:
fprintf(f, "9-bit, signed, word-multiple");
break;
case LC3B_IMM_9_PC:
fprintf(f, "9-bit, signed, word-multiple, PC-relative");
break;
}
indent_level--;
}
fprintf(f, "\n%*sOrigin=", indent_level, "");
if (insn->origin) {
fprintf(f, "\n");
yasm_symrec_print(insn->origin, f, indent_level+1);
} else
fprintf(f, "(nil)\n");
fprintf(f, "%*sOpcode: %04x\n", indent_level, "",
(unsigned int)insn->opcode);
}
static yasm_bc_resolve_flags
lc3b_bc_insn_resolve(yasm_bytecode *bc, int save,
yasm_calc_bc_dist_func calc_bc_dist)
{
lc3b_insn *insn = (lc3b_insn *)bc->contents;
/*@null@*/ yasm_expr *temp;
/*@dependent@*/ /*@null@*/ const yasm_intnum *num;
long rel;
/* Fixed size instruction length */
bc->len = 2;
/* Only need to worry about out-of-range to PC-relative, and only if we're
* saving.
*/
if (insn->imm_type != LC3B_IMM_9_PC || !save)
return YASM_BC_RESOLVE_MIN_LEN;
temp = yasm_expr_copy(insn->imm);
temp = yasm_expr_create(YASM_EXPR_SUB, yasm_expr_expr(temp),
yasm_expr_sym(insn->origin), bc->line);
num = yasm_expr_get_intnum(&temp, calc_bc_dist);
if (!num) {
yasm__error(bc->line, N_("target external or out of segment"));
yasm_expr_destroy(temp);
return YASM_BC_RESOLVE_ERROR | YASM_BC_RESOLVE_UNKNOWN_LEN;
}
rel = yasm_intnum_get_int(num);
rel -= 2;
yasm_expr_destroy(temp);
/* 9-bit signed, word-multiple displacement */
if (rel < -512 || rel > 511) {
yasm__error(bc->line, N_("target out of range"));
return YASM_BC_RESOLVE_ERROR | YASM_BC_RESOLVE_UNKNOWN_LEN;
}
return YASM_BC_RESOLVE_MIN_LEN;
}
static int
lc3b_bc_insn_tobytes(yasm_bytecode *bc, unsigned char **bufp, void *d,
yasm_output_expr_func output_expr,
/*@unused@*/ yasm_output_reloc_func output_reloc)
{
lc3b_insn *insn = (lc3b_insn *)bc->contents;
/* Output opcode */
YASM_SAVE_16_L(*bufp, insn->opcode);
/* Insert immediate into opcode. */
switch (insn->imm_type) {
case LC3B_IMM_NONE:
break;
case LC3B_IMM_4:
if (output_expr(&insn->imm, *bufp, 2, 4, 0, 0, bc, 0, 1, d))
return 1;
break;
case LC3B_IMM_5:
if (output_expr(&insn->imm, *bufp, 2, 5, 0, 0, bc, 0, 1, d))
return 1;
break;
case LC3B_IMM_6_WORD:
if (output_expr(&insn->imm, *bufp, 2, 6, -1, 0, bc, 0, 1, d))
return 1;
break;
case LC3B_IMM_6_BYTE:
if (output_expr(&insn->imm, *bufp, 2, 6, 0, 0, bc, 0, 1, d))
return 1;
break;
case LC3B_IMM_8:
if (output_expr(&insn->imm, *bufp, 2, 8, -1, 0, bc, 0, 1, d))
return 1;
break;
case LC3B_IMM_9_PC:
insn->imm = yasm_expr_create(YASM_EXPR_SUB,
yasm_expr_expr(insn->imm), yasm_expr_sym(insn->origin),
bc->line);
if (output_expr(&insn->imm, *bufp, 2, 9, -1, 0, bc, 1, 1, d))
return 1;
break;
case LC3B_IMM_9:
if (output_expr(&insn->imm, *bufp, 2, 9, -1, 0, bc, 0, 1, d))
return 1;
break;
default:
yasm_internal_error(N_("Unrecognized immediate type"));
}
*bufp += 2; /* all instructions are 2 bytes in size */
return 0;
}
int
yasm_lc3b__intnum_fixup_rel(yasm_arch *arch, yasm_intnum *intn,
size_t valsize, const yasm_bytecode *bc,
unsigned long line)
{
yasm_intnum *delta;
if (valsize != 9)
yasm_internal_error(
N_("tried to do PC-relative offset from invalid sized value"));
delta = yasm_intnum_create_uint(bc->len);
yasm_intnum_calc(intn, YASM_EXPR_SUB, delta, line);
yasm_intnum_destroy(delta);
return 0;
}
int
yasm_lc3b__intnum_tobytes(yasm_arch *arch, const yasm_intnum *intn,
unsigned char *buf, size_t destsize, size_t valsize,
int shift, const yasm_bytecode *bc, int warn,
unsigned long line)
{
/* Write value out. */
yasm_intnum_get_sized(intn, buf, destsize, valsize, shift, 0, warn,
line);
return 0;
}