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/*
* Bytecode utility functions
*
* Copyright (C) 2001-2007 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"
#include "libyasm-stdint.h"
#include "coretype.h"
#include "errwarn.h"
#include "intnum.h"
#include "expr.h"
#include "value.h"
#include "symrec.h"
#include "bytecode.h"
void
yasm_bc_set_multiple(yasm_bytecode *bc, yasm_expr *e)
{
if (bc->multiple)
bc->multiple = yasm_expr_create_tree(bc->multiple, YASM_EXPR_MUL, e,
e->line);
else
bc->multiple = e;
}
void
yasm_bc_finalize_common(yasm_bytecode *bc, yasm_bytecode *prev_bc)
{
}
int
yasm_bc_calc_len_common(yasm_bytecode *bc, yasm_bc_add_span_func add_span,
void *add_span_data)
{
yasm_internal_error(N_("bytecode length cannot be calculated"));
/*@unreached@*/
return 0;
}
int
yasm_bc_expand_common(yasm_bytecode *bc, int span, long old_val, long new_val,
/*@out@*/ long *neg_thres, /*@out@*/ long *pos_thres)
{
yasm_internal_error(N_("bytecode does not have any dependent spans"));
/*@unreached@*/
return 0;
}
int
yasm_bc_tobytes_common(yasm_bytecode *bc, unsigned char **buf,
unsigned char *bufstart, void *d,
yasm_output_value_func output_value,
/*@null@*/ yasm_output_reloc_func output_reloc)
{
yasm_internal_error(N_("bytecode cannot be converted to bytes"));
/*@unreached@*/
return 0;
}
void
yasm_bc_transform(yasm_bytecode *bc, const yasm_bytecode_callback *callback,
void *contents)
{
if (bc->callback)
bc->callback->destroy(bc->contents);
bc->callback = callback;
bc->contents = contents;
}
yasm_bytecode *
yasm_bc_create_common(const yasm_bytecode_callback *callback, void *contents,
unsigned long line)
{
yasm_bytecode *bc = yasm_xmalloc(sizeof(yasm_bytecode));
bc->callback = callback;
bc->section = NULL;
bc->multiple = (yasm_expr *)NULL;
bc->len = 0;
bc->mult_int = 1;
bc->line = line;
bc->offset = ~0UL; /* obviously incorrect / uninitialized value */
bc->symrecs = NULL;
bc->contents = contents;
return bc;
}
yasm_section *
yasm_bc_get_section(yasm_bytecode *bc)
{
return bc->section;
}
void
yasm_bc__add_symrec(yasm_bytecode *bc, yasm_symrec *sym)
{
if (!bc->symrecs) {
bc->symrecs = yasm_xmalloc(2*sizeof(yasm_symrec *));
bc->symrecs[0] = sym;
bc->symrecs[1] = NULL;
} else {
/* Very inefficient implementation for large numbers of symbols. But
* that would be very unusual, so use the simple algorithm instead.
*/
size_t count = 1;
while (bc->symrecs[count])
count++;
bc->symrecs = yasm_xrealloc(bc->symrecs,
(count+2)*sizeof(yasm_symrec *));
bc->symrecs[count] = sym;
bc->symrecs[count+1] = NULL;
}
}
void
yasm_bc_destroy(yasm_bytecode *bc)
{
if (!bc)
return;
if (bc->callback)
bc->callback->destroy(bc->contents);
yasm_expr_destroy(bc->multiple);
if (bc->symrecs)
yasm_xfree(bc->symrecs);
yasm_xfree(bc);
}
void
yasm_bc_print(const yasm_bytecode *bc, FILE *f, int indent_level)
{
if (!bc->callback)
fprintf(f, "%*s_Empty_\n", indent_level, "");
else
bc->callback->print(bc->contents, f, indent_level);
fprintf(f, "%*sMultiple=", indent_level, "");
if (!bc->multiple)
fprintf(f, "nil (1)");
else
yasm_expr_print(bc->multiple, f);
fprintf(f, "\n%*sLength=%lu\n", indent_level, "", bc->len);
fprintf(f, "%*sLine Index=%lu\n", indent_level, "", bc->line);
fprintf(f, "%*sOffset=%lx\n", indent_level, "", bc->offset);
}
void
yasm_bc_finalize(yasm_bytecode *bc, yasm_bytecode *prev_bc)
{
if (bc->callback)
bc->callback->finalize(bc, prev_bc);
if (bc->multiple) {
yasm_value val;
if (yasm_value_finalize_expr(&val, bc->multiple, prev_bc, 0))
yasm_error_set(YASM_ERROR_TOO_COMPLEX,
N_("multiple expression too complex"));
else if (val.rel)
yasm_error_set(YASM_ERROR_NOT_ABSOLUTE,
N_("multiple expression not absolute"));
/* Finalize creates NULL output if value=0, but bc->multiple is NULL
* if value=1 (this difference is to make the common case small).
* However, this means we need to set bc->multiple explicitly to 0
* here if val.abs is NULL.
*/
if (val.abs)
bc->multiple = val.abs;
else
bc->multiple = yasm_expr_create_ident(
yasm_expr_int(yasm_intnum_create_uint(0)), bc->line);
}
}
/*@null@*/ yasm_intnum *
yasm_calc_bc_dist(yasm_bytecode *precbc1, yasm_bytecode *precbc2)
{
unsigned long dist2, dist1;
yasm_intnum *intn;
if (precbc1->section != precbc2->section)
return NULL;
dist1 = yasm_bc_next_offset(precbc1);
dist2 = yasm_bc_next_offset(precbc2);
if (dist2 < dist1) {
intn = yasm_intnum_create_uint(dist1 - dist2);
yasm_intnum_calc(intn, YASM_EXPR_NEG, NULL);
return intn;
}
dist2 -= dist1;
return yasm_intnum_create_uint(dist2);
}
unsigned long
yasm_bc_next_offset(yasm_bytecode *precbc)
{
return precbc->offset + precbc->len*precbc->mult_int;
}
int
yasm_bc_elem_size(yasm_bytecode *bc)
{
if (!bc->callback) {
yasm_internal_error(N_("got empty bytecode in yasm_bc_elem_size"));
return 0;
} else if (!bc->callback->elem_size)
return 0;
else
return bc->callback->elem_size(bc);
}
int
yasm_bc_calc_len(yasm_bytecode *bc, yasm_bc_add_span_func add_span,
void *add_span_data)
{
int retval = 0;
bc->len = 0;
if (!bc->callback)
yasm_internal_error(N_("got empty bytecode in yasm_bc_calc_len"));
else
retval = bc->callback->calc_len(bc, add_span, add_span_data);
/* Check for multiples */
bc->mult_int = 1;
if (bc->multiple) {
/*@dependent@*/ /*@null@*/ const yasm_intnum *num;
num = yasm_expr_get_intnum(&bc->multiple, 0);
if (num) {
if (yasm_intnum_sign(num) < 0) {
yasm_error_set(YASM_ERROR_VALUE, N_("multiple is negative"));
retval = -1;
} else
bc->mult_int = yasm_intnum_get_int(num);
} else {
if (yasm_expr__contains(bc->multiple, YASM_EXPR_FLOAT)) {
yasm_error_set(YASM_ERROR_VALUE,
N_("expression must not contain floating point value"));
retval = -1;
} else {
yasm_value value;
yasm_value_initialize(&value, bc->multiple, 0);
add_span(add_span_data, bc, 0, &value, 0, 0);
bc->mult_int = 0; /* assume 0 to start */
}
}
}
/* If we got an error somewhere along the line, clear out any calc len */
if (retval < 0)
bc->len = 0;
return retval;
}
int
yasm_bc_expand(yasm_bytecode *bc, int span, long old_val, long new_val,
/*@out@*/ long *neg_thres, /*@out@*/ long *pos_thres)
{
if (span == 0) {
bc->mult_int = new_val;
return 1;
}
if (!bc->callback) {
yasm_internal_error(N_("got empty bytecode in yasm_bc_expand"));
/*@unreached@*/
return -1;
} else
return bc->callback->expand(bc, span, old_val, new_val, neg_thres,
pos_thres);
}
/*@null@*/ /*@only@*/ unsigned char *
yasm_bc_tobytes(yasm_bytecode *bc, unsigned char *buf, unsigned long *bufsize,
/*@out@*/ int *gap, void *d,
yasm_output_value_func output_value,
/*@null@*/ yasm_output_reloc_func output_reloc)
/*@sets *buf@*/
{
/*@only@*/ /*@null@*/ unsigned char *mybuf = NULL;
unsigned char *bufstart;
unsigned char *origbuf, *destbuf;
long i;
int error = 0;
long mult;
if (yasm_bc_get_multiple(bc, &mult, 1) || mult == 0) {
*bufsize = 0;
return NULL;
}
bc->mult_int = mult;
/* special case for reserve bytecodes */
if (bc->callback->special == YASM_BC_SPECIAL_RESERVE) {
*bufsize = bc->len*bc->mult_int;
*gap = 1;
return NULL; /* we didn't allocate a buffer */
}
*gap = 0;
if (*bufsize < bc->len*bc->mult_int) {
mybuf = yasm_xmalloc(bc->len*bc->mult_int);
destbuf = mybuf;
} else
destbuf = buf;
bufstart = destbuf;
*bufsize = bc->len*bc->mult_int;
if (!bc->callback)
yasm_internal_error(N_("got empty bytecode in bc_tobytes"));
else for (i=0; i<bc->mult_int; i++) {
origbuf = destbuf;
error = bc->callback->tobytes(bc, &destbuf, bufstart, d, output_value,
output_reloc);
if (!error && ((unsigned long)(destbuf - origbuf) != bc->len))
yasm_internal_error(
N_("written length does not match optimized length"));
}
return mybuf;
}
int
yasm_bc_get_multiple(yasm_bytecode *bc, long *multiple, int calc_bc_dist)
{
/*@dependent@*/ /*@null@*/ const yasm_intnum *num;
*multiple = 1;
if (bc->multiple) {
num = yasm_expr_get_intnum(&bc->multiple, calc_bc_dist);
if (!num) {
yasm_error_set(YASM_ERROR_VALUE,
N_("could not determine multiple"));
return 1;
}
if (yasm_intnum_sign(num) < 0) {
yasm_error_set(YASM_ERROR_VALUE, N_("multiple is negative"));
return 1;
}
*multiple = yasm_intnum_get_int(num);
}
return 0;
}
const yasm_expr *
yasm_bc_get_multiple_expr(const yasm_bytecode *bc)
{
return bc->multiple;
}
yasm_insn *
yasm_bc_get_insn(yasm_bytecode *bc)
{
if (bc->callback->special != YASM_BC_SPECIAL_INSN)
return NULL;
return (yasm_insn *)bc->contents;
}
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