diff options
Diffstat (limited to 'output.c')
| -rw-r--r-- | output.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/output.c b/output.c new file mode 100644 index 0000000..ff22956 --- /dev/null +++ b/output.c @@ -0,0 +1,203 @@ +#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; + uint16_t imm = 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 + + printf("output: have %d instructions\n", insts_count); + + for (i = 0; i < insts_count; i++) + if (output_single(fout, labels, label_count, insts[i])) + return 1; + + return 0; +} |