// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/***************************************************************************
x86log.c
x86/x64 code logging helpers.
***************************************************************************/
#include <cstdint>
#include <cassert>
#include "emu.h"
#include "x86log.h"
#include "cpu/i386/i386dasm.h"
/***************************************************************************
FUNCTION PROTOTYPES
***************************************************************************/
static void reset_log(x86log_context *log) noexcept;
/***************************************************************************
EXTERNAL INTERFACES
***************************************************************************/
/*-------------------------------------------------
x86log_create_context - create a new context
-------------------------------------------------*/
x86log_context *x86log_create_context(const char *filename)
{
x86log_context *log;
/* allocate the log */
log = global_alloc_clear<x86log_context>();
/* allocate the filename */
log->filename.assign(filename);
/* reset things */
reset_log(log);
return log;
}
/*-------------------------------------------------
x86log_free_context - release a context
-------------------------------------------------*/
void x86log_free_context(x86log_context *log) noexcept
{
/* close any open files */
if (log->file != nullptr)
fclose(log->file);
/* free the structure */
global_free(log);
}
/*-------------------------------------------------
x86log_mark_as_data - mark a given range as
data for logging purposes
-------------------------------------------------*/
void x86log_mark_as_data(x86log_context *log, x86code *base, x86code *end, int size) noexcept
{
data_range_t *data;
assert(log->data_range_count < MAX_DATA_RANGES);
assert(end >= base);
assert(size == 1 || size == 2 || size == 4 || size == 8);
/* we assume data ranges are registered in order; enforce this */
assert(log->data_range_count == 0 || base > log->data_range[log->data_range_count - 1].end);
/* if we exceed the maxima, skip it */
if (log->data_range_count >= MAX_DATA_RANGES)
return;
/* fill in the new range */
data = &log->data_range[log->data_range_count++];
data->base = base;
data->end = end;
data->size = size;
}
/*-------------------------------------------------
x86log_disasm_code_range - disassemble a range
of code and reset accumulated information
-------------------------------------------------*/
namespace {
class x86_buf : public util::disasm_interface::data_buffer {
public:
x86_buf(offs_t _base_pc, const u8 *_buf) : base_pc(_base_pc), buf(_buf) {}
~x86_buf() = default;
// We know we're on a x86, so we can go short
virtual u8 r8 (offs_t pc) const override { return *(u8 *)(buf + pc - base_pc); }
virtual u16 r16(offs_t pc) const override { return *(u16 *)(buf + pc - base_pc); }
virtual u32 r32(offs_t pc) const override { return *(u32 *)(buf + pc - base_pc); }
virtual u64 r64(offs_t pc) const override { return *(u64 *)(buf + pc - base_pc); }
private:
offs_t base_pc;
const u8 *buf;
};
class x86_config : public i386_disassembler::config {
public:
~x86_config() = default;
virtual int get_mode() const override { return sizeof(void *) * 8; };
};
}
void x86log_disasm_code_range(x86log_context *log, const char *label, x86code *start, x86code *stop)
{
const log_comment *lastcomment = &log->comment_list[log->comment_count];
const log_comment *curcomment = &log->comment_list[0];
const data_range_t *lastdata = &log->data_range[log->data_range_count];
const data_range_t *curdata = &log->data_range[0];
x86code *cur = start;
/* print the optional label */
if (label != nullptr)
x86log_printf(log, "\n%s\n", label);
/* loop from the start until the cache top */
while (cur < stop)
{
std::string buffer;
int bytes;
/* skip past any past data ranges */
while (curdata < lastdata && cur > curdata->end)
curdata++;
/* skip past any past comments */
while (curcomment < lastcomment && cur > curcomment->base)
curcomment++;
/* if we're in a data range, output the next chunk and continue */
if (cur >= curdata->base && cur <= curdata->end)
{
bytes = curdata->size;
switch (curdata->size)
{
default:
case 1: buffer = string_format("db %02X", *cur); break;
case 2: buffer = string_format("dw %04X", *(uint16_t *)cur); break;
case 4: buffer = string_format("dd %08X", *(uint32_t *)cur); break;
case 8: buffer = string_format("dq %08X%08X", ((uint32_t *)cur)[1], ((uint32_t *)cur)[0]); break;
}
}
/* if we're not in the data range, skip filler opcodes */
else if (*cur == 0xcc)
{
cur++;
continue;
}
/* otherwise, do a disassembly of the current instruction */
else
{
std::stringstream strbuffer;
offs_t pc = (uintptr_t)cur;
x86_buf buf(pc, cur);
x86_config conf;
i386_disassembler dis(&conf);
bytes = dis.disassemble(strbuffer, pc, buf, buf) & util::disasm_interface::LENGTHMASK;
buffer = strbuffer.str();
}
/* if we have a matching comment, output it */
if (curcomment < lastcomment && cur == curcomment->base)
{
/* if we have additional matching comments at the same address, output them first */
for ( ; curcomment + 1 < lastcomment && cur == curcomment[1].base; curcomment++)
x86log_printf(log, "%p: %-50s; %s\n", cur, "", curcomment->string);
x86log_printf(log, "%p: %-50s; %s\n", cur, buffer.c_str(), curcomment->string);
}
/* if we don't, just print the disassembly and move on */
else
x86log_printf(log, "%p: %s\n", cur, buffer.c_str());
/* advance past this instruction */
cur += bytes;
}
/* reset our state */
reset_log(log);
}
/***************************************************************************
LOCAL FUNCTIONS
***************************************************************************/
/*-------------------------------------------------
reset_log - reset the state of the log
-------------------------------------------------*/
static void reset_log(x86log_context *log) noexcept
{
log->data_range_count = 0;
log->comment_count = 0;
log->comment_pool_next = log->comment_pool;
}