#include <string.h>
#include <mruby.h>
#include <mruby/irep.h>
#include <mruby/debug.h>
static mrb_irep_debug_info_file*
get_file(mrb_irep_debug_info *info, uint32_t pc)
{
mrb_irep_debug_info_file **ret;
int32_t count;
if (pc >= info->pc_count) { return NULL; }
ret = info->files;
count = info->flen;
while (count > 0) {
int32_t step = count / 2;
mrb_irep_debug_info_file **it = ret + step;
if (!(pc < (*it)->start_pos)) {
ret = it + 1;
count -= step + 1;
}
else { count = step; }
}
--ret;
mrb_assert(info->files <= ret && ret < (info->files + info->flen));
mrb_assert((*ret)->start_pos <= pc &&
pc < (((ret + 1 - info->files) < info->flen)
? (*(ret+1))->start_pos : info->pc_count));
return *ret;
}
size_t
mrb_packed_int_len(uint32_t num)
{
size_t llen = 0;
do {
llen++;
} while (num >>= 7);
return llen;
}
size_t
mrb_packed_int_encode(uint32_t num, uint8_t *p, uint8_t *pend)
{
size_t llen = 0;
do {
uint8_t byte = num & 0x7f;
num >>= 7;
if (num != 0) byte |= 0x80;
if (p < pend) *p++ = byte;
llen++;
} while (num != 0);
return llen;
}
uint32_t
mrb_packed_int_decode(const uint8_t *p, const uint8_t **newpos)
{
size_t i = 0, shift = 0;
uint32_t n = 0;
do {
n |= ((uint32_t)(p[i] & 0x7f)) << shift;
i++;
shift += 7;
} while (shift < sizeof(uint32_t) * 8 && (p[i - 1] & 0x80));
if (newpos) *newpos = p + i;
return n;
}
MRB_API char const*
mrb_debug_get_filename(mrb_state *mrb, const mrb_irep *irep, uint32_t pc)
{
if (irep && pc < irep->ilen) {
mrb_irep_debug_info_file* f = NULL;
if (!irep->debug_info) return NULL;
else if ((f = get_file(irep->debug_info, pc))) {
return mrb_sym_name_len(mrb, f->filename_sym, NULL);
}
}
return NULL;
}
MRB_API int32_t
mrb_debug_get_line(mrb_state *mrb, const mrb_irep *irep, uint32_t pc)
{
if (irep && pc < irep->ilen) {
mrb_irep_debug_info_file* f = NULL;
if (!irep->debug_info) {
return -1;
}
else if ((f = get_file(irep->debug_info, pc))) {
switch (f->line_type) {
case mrb_debug_line_ary:
mrb_assert(f->start_pos <= pc && pc < (f->start_pos + f->line_entry_count));
return f->lines.ary[pc - f->start_pos];
case mrb_debug_line_flat_map: {
const mrb_irep_debug_info_line *ret = f->lines.flat_map;
uint32_t count = f->line_entry_count;
while (count > 0) {
int32_t step = count / 2;
const mrb_irep_debug_info_line *it = ret + step;
if (!(pc < it->start_pos)) {
ret = it + 1;
count -= step + 1;
}
else { count = step; }
}
--ret;
mrb_assert(f->lines.flat_map <= ret && ret < (f->lines.flat_map + f->line_entry_count));
mrb_assert(ret->start_pos <= pc &&
pc < (((uint32_t)(ret + 1 - f->lines.flat_map) < f->line_entry_count)
? (ret+1)->start_pos : irep->debug_info->pc_count));
return ret->line;
}
case mrb_debug_line_packed_map: {
const uint8_t *p = f->lines.packed_map;
const uint8_t *pend = p + f->line_entry_count;
uint32_t pos = 0, line = 0, line_diff;
while (p < pend) {
pos += mrb_packed_int_decode(p, &p);
line_diff = mrb_packed_int_decode(p, &p);
if (pc < pos) break;
line += line_diff;
}
return line;
}
}
}
}
return -1;
}
MRB_API mrb_irep_debug_info*
mrb_debug_info_alloc(mrb_state *mrb, mrb_irep *irep)
{
static const mrb_irep_debug_info initial = { 0, 0, NULL };
mrb_irep_debug_info *ret;
mrb_assert(!irep->debug_info);
ret = (mrb_irep_debug_info *)mrb_malloc(mrb, sizeof(*ret));
*ret = initial;
irep->debug_info = ret;
return ret;
}
MRB_API mrb_irep_debug_info_file*
mrb_debug_info_append_file(mrb_state *mrb, mrb_irep_debug_info *d,
const char *filename, uint16_t *lines,
uint32_t start_pos, uint32_t end_pos)
{
mrb_irep_debug_info_file *f;
uint32_t file_pc_count;
size_t fn_len;
uint32_t i;
if (!d) return NULL;
if (start_pos == end_pos) return NULL;
mrb_assert(filename);
mrb_assert(lines);
if (d->flen > 0) {
const char *fn = mrb_sym_name_len(mrb, d->files[d->flen - 1]->filename_sym, NULL);
if (strcmp(filename, fn) == 0)
return NULL;
}
f = (mrb_irep_debug_info_file*)mrb_malloc(mrb, sizeof(*f));
d->files = (mrb_irep_debug_info_file**)mrb_realloc(mrb, d->files, sizeof(mrb_irep_debug_info_file*) * (d->flen + 1));
d->files[d->flen++] = f;
file_pc_count = end_pos - start_pos;
f->start_pos = start_pos;
d->pc_count = end_pos;
fn_len = strlen(filename);
f->filename_sym = mrb_intern(mrb, filename, fn_len);
f->line_type = mrb_debug_line_packed_map;
f->lines.ptr = NULL;
uint16_t prev_line = 0;
uint32_t prev_pc = 0;
size_t packed_size = 0;
uint8_t *p, *pend;
for (i = 0; i < file_pc_count; i++) {
if (lines[start_pos + i] == prev_line) continue;
packed_size += mrb_packed_int_len(start_pos+i-prev_pc);
prev_pc = start_pos+i;
packed_size += mrb_packed_int_len(lines[start_pos+i]-prev_line);
prev_line = lines[start_pos + i];
}
f->lines.packed_map = p = (uint8_t*)mrb_malloc(mrb, packed_size);
pend = p + packed_size;
prev_line = 0; prev_pc = 0;
for (i = 0; i < file_pc_count; i++) {
if (lines[start_pos + i] == prev_line) continue;
p += mrb_packed_int_encode(start_pos+i-prev_pc, p, pend);
prev_pc = start_pos + i;
p += mrb_packed_int_encode(lines[start_pos + i]-prev_line, p, pend);
prev_line = lines[start_pos + i];
}
f->line_entry_count = (uint32_t)packed_size;
return f;
}
MRB_API void
mrb_debug_info_free(mrb_state *mrb, mrb_irep_debug_info *d)
{
uint32_t i;
if (!d) { return; }
if (d->files) {
for (i = 0; i < d->flen; i++) {
if (d->files[i]) {
mrb_free(mrb, d->files[i]->lines.ptr);
mrb_free(mrb, d->files[i]);
}
}
mrb_free(mrb, d->files);
}
mrb_free(mrb, d);
}