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#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include "parse.h"
static size_t cur_byte;
int generate_single_r_type(uint32_t *dest, struct r_type inst)
{
uint32_t i = 0;
i |= MASK_INST_RTYPE;
i |= MASK_OPER(inst.oper);
i |= MASK_REG_DEST(inst.dest);
i |= MASK_REG_LEFT(inst.left);
i |= MASK_REG_RIGHT(inst.right);
*dest = i;
return 1;
}
int generate_single_ni_type(uint32_t *dest, struct i_type inst)
{
uint32_t i = 0;
i |= MASK_INST_NITYPE;
i |= MASK_OPER(inst.oper);
i |= MASK_REG_DEST(inst.dest);
i |= MASK_REG_LEFT(inst.left);
i |= MASK_NI_IMM(inst.imm.value);
*dest = i;
return 1;
}
int generate_single_wi_type(uint32_t *dest, struct i_type inst)
{
uint32_t i = 0;
i |= MASK_INST_WITYPE;
i |= MASK_OPER(inst.oper);
i |= MASK_REG_DEST(inst.dest);
i |= MASK_REG_LEFT(inst.left);
/* two-word instruction - make room for the immediate */
i <<= 16;
i |= inst.imm.value;
*dest = i;
return 2;
}
int generate_single_ji_type(uint32_t *dest, struct ji_type inst)
{
uint32_t i = 0;
i |= MASK_INST_JTYPE;
i |= MASK_IS_JUMP;
i |= MASK_JB_COND(inst.cond);
i |= MASK_JI;
/* two-word instruction - make room for the immediate */
i <<= 16;
i |= inst.imm.value;
*dest = i;
return 2;
}
int generate_single_jr_type(uint32_t *dest, struct jr_type inst)
{
uint32_t i = 0;
i |= MASK_INST_JTYPE;
i |= MASK_IS_JUMP;
i |= MASK_JB_COND(inst.cond);
i |= MASK_JR;
i |= MASK_JUMP_REGISTER(inst.reg);
*dest = i;
return 1;
}
int generate_single_b_type(uint32_t *dest, struct b_type inst)
{
uint32_t i = 0;
i |= MASK_INST_JTYPE;
i |= MASK_IS_BRANCH;
i |= MASK_JB_COND(inst.cond);
i |= MASK_B_OFFSET(inst.imm.value);
*dest = i;
return 1;
}
int look_up_label(struct label *labels, size_t labels_count, uint16_t *val, const char *label)
{
size_t i = 0;
for (i = 0; i < labels_count; i++) {
if (strcmp(labels[i].name, label) == 0) {
*val = labels[i].byte_offset;
return 0;
}
}
/* FIXME emit */
fprintf(stderr, "Reference to undefined label `%s'\n", label);
return 1;
}
int output_single(FILE *f, struct label *labels, size_t labels_count, struct instruction inst)
{
int len = 0;
uint32_t i = 0;
switch (inst.type) {
case INST_TYPE_R:
len = generate_single_r_type(&i, inst.inst.r);
break;
case INST_TYPE_NI:
if ( inst.inst.i.imm_is_ident
&& look_up_label(labels, labels_count, &inst.inst.i.imm.value, inst.inst.i.imm.label))
return 1;
len = generate_single_ni_type(&i, inst.inst.i);
break;
case INST_TYPE_WI:
if ( inst.inst.i.imm_is_ident
&& look_up_label(labels, labels_count, &inst.inst.i.imm.value, inst.inst.i.imm.label))
return 1;
len = generate_single_wi_type(&i, inst.inst.i);
break;
case INST_TYPE_JR:
len = generate_single_jr_type(&i, inst.inst.jr);
break;
case INST_TYPE_JI:
if ( inst.inst.ji.imm_is_ident
&& look_up_label(labels, labels_count, &inst.inst.ji.imm.value, inst.inst.ji.imm.label))
return 1;
len = generate_single_ji_type(&i, inst.inst.ji);
break;
case INST_TYPE_B:
if ( inst.inst.b.imm_is_ident
&& look_up_label(labels, labels_count, &inst.inst.b.imm.value, inst.inst.b.imm.label))
return 1;
inst.inst.b.imm.value -= cur_byte;
if (inst.inst.b.imm.value % 2 != 0) {
fprintf(stderr, "Internal error: branch offset %d not a multiple of 2\n", inst.inst.b.imm.value);
}
inst.inst.b.imm.value /= 2;
len = generate_single_b_type(&i, inst.inst.b);
break;
default:
fprintf(stderr, "Internal error: unhandled instruction type\n");
break;
}
if (len == 2) {
#define RAW
#ifdef RAW
fputc(0xFF & (i >> 24), f);
fputc(0xFF & (i >> 16), f);
#else
fprintf(f, "%04x ", i >> 16);
#endif
}
#ifdef RAW
fputc(0xFF & (i >> 8), f);
fputc(0xFF & (i >> 0), f);
#else
fprintf(f, "%04x ", 0xFFFF & i);
#endif
cur_byte += 2 * len;
return 0;
}
int output(FILE *fout, struct label *labels, size_t label_count, struct instruction *insts, size_t insts_count)
{
size_t i = 0;
cur_byte = 0;
#ifndef RAW
fprintf(fout, "v2.0 raw\n");
#endif
for (i = 0; i < insts_count; i++)
if (output_single(fout, labels, label_count, insts[i]))
return 1;
return 0;
}
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