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Lines 32-37
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#include "config-host.h" |
33 |
#include "config-host.h" |
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35 |
//#define DEBUG_OP |
| 36 |
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| 35 |
/* NOTE: we test CONFIG_WIN32 instead of _WIN32 to enabled cross |
37 |
/* NOTE: we test CONFIG_WIN32 instead of _WIN32 to enabled cross |
| 36 |
compilation */ |
38 |
compilation */ |
| 37 |
#if defined(CONFIG_WIN32) |
39 |
#if defined(CONFIG_WIN32) |
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Lines 1343-1348
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| 1343 |
#endif |
1345 |
#endif |
| 1344 |
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1346 |
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| 1345 |
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1347 |
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1348 |
#if defined(HOST_I386) || defined(HOST_X86_64) |
| 1349 |
|
| 1350 |
/* This byte is the first byte of an instruction. */ |
| 1351 |
#define FLAG_INSN (1 << 0) |
| 1352 |
/* This byte has been processed as part of an instruction. */ |
| 1353 |
#define FLAG_SCANNED (1 << 1) |
| 1354 |
/* This instruction is a return instruction. Gcc cometimes generates prefix |
| 1355 |
bytes, so may be more than one byte long. */ |
| 1356 |
#define FLAG_RET (1 << 2) |
| 1357 |
/* This is either the target of a jump, or the preceeding instruction uses |
| 1358 |
a pc-relative offset. */ |
| 1359 |
#define FLAG_TARGET (1 << 3) |
| 1360 |
/* This is a magic instruction that needs fixing up. */ |
| 1361 |
#define FLAG_EXIT (1 << 4) |
| 1362 |
/* This instruction clobbers the stack pointer. */ |
| 1363 |
/* XXX only supports push, pop, add/sub $imm,%esp */ |
| 1364 |
#define FLAG_STACK (1 << 5) |
| 1365 |
#define MAX_EXITS 5 |
| 1366 |
|
| 1367 |
static void |
| 1368 |
bad_opcode(const char *name, uint32_t op) |
| 1369 |
{ |
| 1370 |
error("Unsupported opcode %0*x in %s", (op > 0xff) ? 4 : 2, op, name); |
| 1371 |
} |
| 1372 |
|
| 1373 |
/* Mark len bytes as scanned, Returns insn_size + len. Reports an error |
| 1374 |
if these bytes have already been scanned. */ |
| 1375 |
static int |
| 1376 |
eat_bytes(const char *name, char *flags, int insn, int insn_size, int len) |
| 1377 |
{ |
| 1378 |
while (len > 0) { |
| 1379 |
/* This should never occur in sane code. */ |
| 1380 |
if (flags[insn + insn_size] & FLAG_SCANNED) |
| 1381 |
error ("Overlapping instructions in %s", name); |
| 1382 |
flags[insn + insn_size] |= FLAG_SCANNED; |
| 1383 |
insn_size++; |
| 1384 |
len--; |
| 1385 |
} |
| 1386 |
return insn_size; |
| 1387 |
} |
| 1388 |
|
| 1389 |
static void |
| 1390 |
trace_i386_insn (const char *name, uint8_t *start_p, char *flags, int insn, |
| 1391 |
int len) |
| 1392 |
{ |
| 1393 |
uint8_t *ptr; |
| 1394 |
uint8_t op; |
| 1395 |
int modrm; |
| 1396 |
int is_prefix; |
| 1397 |
int op_size; |
| 1398 |
int addr_size; |
| 1399 |
int insn_size; |
| 1400 |
int is_ret; |
| 1401 |
int is_condjmp; |
| 1402 |
int is_jmp; |
| 1403 |
int is_exit; |
| 1404 |
int is_pcrel; |
| 1405 |
int is_stack; |
| 1406 |
int immed; |
| 1407 |
int seen_rexw; |
| 1408 |
int32_t disp; |
| 1409 |
|
| 1410 |
ptr = start_p + insn; |
| 1411 |
/* nonzero if this insn has a ModR/M byte. */ |
| 1412 |
modrm = 1; |
| 1413 |
/* The size of the immediate value in this instruction. */ |
| 1414 |
immed = 0; |
| 1415 |
/* The operand size. */ |
| 1416 |
op_size = 4; |
| 1417 |
/* The address size */ |
| 1418 |
addr_size = 4; |
| 1419 |
/* The total length of this instruction. */ |
| 1420 |
insn_size = 0; |
| 1421 |
is_prefix = 1; |
| 1422 |
is_ret = 0; |
| 1423 |
is_condjmp = 0; |
| 1424 |
is_jmp = 0; |
| 1425 |
is_exit = 0; |
| 1426 |
seen_rexw = 0; |
| 1427 |
is_pcrel = 0; |
| 1428 |
is_stack = 0; |
| 1429 |
|
| 1430 |
while (is_prefix) { |
| 1431 |
op = ptr[insn_size]; |
| 1432 |
insn_size = eat_bytes(name, flags, insn, insn_size, 1); |
| 1433 |
is_prefix = 0; |
| 1434 |
switch (op >> 4) { |
| 1435 |
case 0: |
| 1436 |
case 1: |
| 1437 |
case 2: |
| 1438 |
case 3: |
| 1439 |
if (op == 0x0f) { |
| 1440 |
/* two-byte opcode. */ |
| 1441 |
op = ptr[insn_size]; |
| 1442 |
insn_size = eat_bytes(name, flags, insn, insn_size, 1); |
| 1443 |
switch (op >> 4) { |
| 1444 |
case 0: |
| 1445 |
if ((op & 0xf) > 3) |
| 1446 |
modrm = 0; |
| 1447 |
break; |
| 1448 |
case 1: /* vector move or prefetch */ |
| 1449 |
case 2: /* various moves and vector compares. */ |
| 1450 |
case 4: /* cmov */ |
| 1451 |
case 5: /* vector instructions */ |
| 1452 |
case 6: |
| 1453 |
case 13: |
| 1454 |
case 14: |
| 1455 |
case 15: |
| 1456 |
break; |
| 1457 |
case 7: /* mmx */ |
| 1458 |
if (op & 0x77) /* emms */ |
| 1459 |
modrm = 0; |
| 1460 |
break; |
| 1461 |
case 3: /* wrmsr, rdtsc, rdmsr, rdpmc, sysenter, sysexit */ |
| 1462 |
modrm = 0; |
| 1463 |
break; |
| 1464 |
case 8: /* long conditional jump */ |
| 1465 |
is_condjmp = 1; |
| 1466 |
immed = op_size; |
| 1467 |
modrm = 0; |
| 1468 |
break; |
| 1469 |
case 9: /* setcc */ |
| 1470 |
break; |
| 1471 |
case 10: |
| 1472 |
switch (op & 0x7) { |
| 1473 |
case 0: /* push fs/gs */ |
| 1474 |
case 1: /* pop fs/gs */ |
| 1475 |
is_stack = 1; |
| 1476 |
case 2: /* cpuid/rsm */ |
| 1477 |
modrm = 0; |
| 1478 |
break; |
| 1479 |
case 4: /* shld/shrd immediate */ |
| 1480 |
immed = 1; |
| 1481 |
break; |
| 1482 |
default: /* Normal instructions with a ModR/M byte. */ |
| 1483 |
break; |
| 1484 |
} |
| 1485 |
break; |
| 1486 |
case 11: |
| 1487 |
switch (op & 0xf) { |
| 1488 |
case 10: /* bt, bts, btr, btc */ |
| 1489 |
immed = 1; |
| 1490 |
break; |
| 1491 |
default: |
| 1492 |
/* cmpxchg, lss, btr, lfs, lgs, movzx, btc, bsf, bsr |
| 1493 |
undefined, and movsx */ |
| 1494 |
break; |
| 1495 |
} |
| 1496 |
break; |
| 1497 |
case 12: |
| 1498 |
if (op & 8) { |
| 1499 |
/* bswap */ |
| 1500 |
modrm = 0; |
| 1501 |
} else { |
| 1502 |
switch (op & 0x7) { |
| 1503 |
case 2: |
| 1504 |
case 4: |
| 1505 |
case 5: |
| 1506 |
case 6: |
| 1507 |
immed = 1; |
| 1508 |
break; |
| 1509 |
default: |
| 1510 |
break; |
| 1511 |
} |
| 1512 |
} |
| 1513 |
break; |
| 1514 |
} |
| 1515 |
} else if ((op & 0x07) <= 0x3) { |
| 1516 |
/* General arithmentic ax. */ |
| 1517 |
} else if ((op & 0x07) <= 0x5) { |
| 1518 |
/* General arithmetic ax, immediate. */ |
| 1519 |
if (op & 0x01) |
| 1520 |
immed = op_size; |
| 1521 |
else |
| 1522 |
immed = 1; |
| 1523 |
modrm = 0; |
| 1524 |
} else if ((op & 0x23) == 0x22) { |
| 1525 |
/* Segment prefix. */ |
| 1526 |
is_prefix = 1; |
| 1527 |
} else { |
| 1528 |
/* Segment register push/pop or DAA/AAA/DAS/AAS. */ |
| 1529 |
modrm = 0; |
| 1530 |
} |
| 1531 |
break; |
| 1532 |
|
| 1533 |
#if defined(HOST_X86_64) |
| 1534 |
case 4: /* rex prefix. */ |
| 1535 |
is_prefix = 1; |
| 1536 |
/* The address/operand size is actually 64-bit, but the immediate |
| 1537 |
values in the instruction are still 32-bit. */ |
| 1538 |
op_size = 4; |
| 1539 |
addr_size = 4; |
| 1540 |
if (op & 8) |
| 1541 |
seen_rexw = 1; |
| 1542 |
break; |
| 1543 |
#else |
| 1544 |
case 4: /* inc/dec register. */ |
| 1545 |
#endif |
| 1546 |
case 5: /* push/pop general register. */ |
| 1547 |
modrm = 0; |
| 1548 |
is_stack = 1; |
| 1549 |
break; |
| 1550 |
|
| 1551 |
case 6: |
| 1552 |
switch (op & 0x0f) { |
| 1553 |
case 0: /* pusha */ |
| 1554 |
case 1: /* popa */ |
| 1555 |
modrm = 0; |
| 1556 |
is_stack = 1; |
| 1557 |
break; |
| 1558 |
case 2: /* bound */ |
| 1559 |
case 3: /* arpl */ |
| 1560 |
break; |
| 1561 |
case 4: /* FS */ |
| 1562 |
case 5: /* GS */ |
| 1563 |
is_prefix = 1; |
| 1564 |
break; |
| 1565 |
case 6: /* opcode size prefix. */ |
| 1566 |
op_size = 2; |
| 1567 |
is_prefix = 1; |
| 1568 |
break; |
| 1569 |
case 7: /* Address size prefix. */ |
| 1570 |
addr_size = 2; |
| 1571 |
is_prefix = 1; |
| 1572 |
break; |
| 1573 |
case 8: /* push immediate */ |
| 1574 |
immed = op_size; |
| 1575 |
modrm = 0; |
| 1576 |
is_stack = 1; |
| 1577 |
break; |
| 1578 |
case 10: /* push 8-bit immediate */ |
| 1579 |
immed = 1; |
| 1580 |
modrm = 0; |
| 1581 |
is_stack = 1; |
| 1582 |
break; |
| 1583 |
case 9: /* imul immediate */ |
| 1584 |
immed = op_size; |
| 1585 |
break; |
| 1586 |
case 11: /* imul 8-bit immediate */ |
| 1587 |
immed = 1; |
| 1588 |
break; |
| 1589 |
case 12: /* insb */ |
| 1590 |
case 13: /* insw */ |
| 1591 |
case 14: /* outsb */ |
| 1592 |
case 15: /* outsw */ |
| 1593 |
modrm = 0; |
| 1594 |
break; |
| 1595 |
} |
| 1596 |
break; |
| 1597 |
|
| 1598 |
case 7: /* Short conditional jump. */ |
| 1599 |
is_condjmp = 1; |
| 1600 |
immed = 1; |
| 1601 |
modrm = 0; |
| 1602 |
break; |
| 1603 |
|
| 1604 |
case 8: |
| 1605 |
if ((op & 0xf) <= 3) { |
| 1606 |
/* arithmetic immediate. */ |
| 1607 |
if ((op & 3) == 1) |
| 1608 |
immed = op_size; |
| 1609 |
else |
| 1610 |
immed = 1; |
| 1611 |
if (op == 0x81 || op == 0x83) { |
| 1612 |
/* add, sub */ |
| 1613 |
op = ptr[insn_size]; |
| 1614 |
switch ((op >> 3) & 7) { |
| 1615 |
case 0: |
| 1616 |
case 5: |
| 1617 |
is_stack = (op & 7) == 4; |
| 1618 |
break; |
| 1619 |
} |
| 1620 |
} |
| 1621 |
} |
| 1622 |
else if ((op & 0xf) == 0xf) { |
| 1623 |
/* pop general. */ |
| 1624 |
is_stack = 1; |
| 1625 |
} |
| 1626 |
/* else test, xchg, mov, lea. */ |
| 1627 |
break; |
| 1628 |
|
| 1629 |
case 9: |
| 1630 |
/* Various single-byte opcodes with no modrm byte. */ |
| 1631 |
modrm = 0; |
| 1632 |
if (op == 10) { |
| 1633 |
/* Call */ |
| 1634 |
immed = 4; |
| 1635 |
} |
| 1636 |
break; |
| 1637 |
|
| 1638 |
case 10: |
| 1639 |
switch ((op & 0xe) >> 1) { |
| 1640 |
case 0: /* mov absoliute immediate. */ |
| 1641 |
case 1: |
| 1642 |
if (seen_rexw) |
| 1643 |
immed = 8; |
| 1644 |
else |
| 1645 |
immed = addr_size; |
| 1646 |
break; |
| 1647 |
case 4: /* test immediate. */ |
| 1648 |
if (op & 1) |
| 1649 |
immed = op_size; |
| 1650 |
else |
| 1651 |
immed = 1; |
| 1652 |
break; |
| 1653 |
default: /* Various string ops. */ |
| 1654 |
break; |
| 1655 |
} |
| 1656 |
modrm = 0; |
| 1657 |
break; |
| 1658 |
|
| 1659 |
case 11: /* move immediate to register */ |
| 1660 |
if (op & 8) { |
| 1661 |
if (seen_rexw) |
| 1662 |
immed = 8; |
| 1663 |
else |
| 1664 |
immed = op_size; |
| 1665 |
} else { |
| 1666 |
immed = 1; |
| 1667 |
} |
| 1668 |
modrm = 0; |
| 1669 |
break; |
| 1670 |
|
| 1671 |
case 12: |
| 1672 |
switch (op & 0xf) { |
| 1673 |
case 0: /* shift immediate */ |
| 1674 |
case 1: |
| 1675 |
immed = 1; |
| 1676 |
break; |
| 1677 |
case 2: /* ret immediate */ |
| 1678 |
immed = 2; |
| 1679 |
modrm = 0; |
| 1680 |
bad_opcode(name, op); |
| 1681 |
break; |
| 1682 |
case 3: /* ret */ |
| 1683 |
modrm = 0; |
| 1684 |
is_ret = 1; |
| 1685 |
case 4: /* les */ |
| 1686 |
case 5: /* lds */ |
| 1687 |
break; |
| 1688 |
case 6: /* mov immediate byte */ |
| 1689 |
immed = 1; |
| 1690 |
break; |
| 1691 |
case 7: /* mov immediate */ |
| 1692 |
immed = op_size; |
| 1693 |
break; |
| 1694 |
case 8: /* enter */ |
| 1695 |
/* TODO: Is this right? */ |
| 1696 |
immed = 3; |
| 1697 |
modrm = 0; |
| 1698 |
break; |
| 1699 |
case 10: /* retf immediate */ |
| 1700 |
immed = 2; |
| 1701 |
modrm = 0; |
| 1702 |
bad_opcode(name, op); |
| 1703 |
break; |
| 1704 |
case 13: /* int */ |
| 1705 |
immed = 1; |
| 1706 |
modrm = 0; |
| 1707 |
break; |
| 1708 |
case 11: /* retf */ |
| 1709 |
case 15: /* iret */ |
| 1710 |
modrm = 0; |
| 1711 |
bad_opcode(name, op); |
| 1712 |
break; |
| 1713 |
default: /* leave, int3 or into */ |
| 1714 |
modrm = 0; |
| 1715 |
break; |
| 1716 |
} |
| 1717 |
break; |
| 1718 |
|
| 1719 |
case 13: |
| 1720 |
if ((op & 0xf) >= 8) { |
| 1721 |
/* Coprocessor escape. For our purposes this is just a normal |
| 1722 |
instruction with a ModR/M byte. */ |
| 1723 |
} else if ((op & 0xf) >= 4) { |
| 1724 |
/* AAM, AAD or XLAT */ |
| 1725 |
modrm = 0; |
| 1726 |
} |
| 1727 |
/* else shift instruction */ |
| 1728 |
break; |
| 1729 |
|
| 1730 |
case 14: |
| 1731 |
switch ((op & 0xc) >> 2) { |
| 1732 |
case 0: /* loop or jcxz */ |
| 1733 |
is_condjmp = 1; |
| 1734 |
immed = 1; |
| 1735 |
break; |
| 1736 |
case 1: /* in/out immed */ |
| 1737 |
immed = 1; |
| 1738 |
break; |
| 1739 |
case 2: /* call or jmp */ |
| 1740 |
switch (op & 3) { |
| 1741 |
case 0: /* call */ |
| 1742 |
immed = op_size; |
| 1743 |
break; |
| 1744 |
case 1: /* long jump */ |
| 1745 |
immed = 4; |
| 1746 |
is_jmp = 1; |
| 1747 |
break; |
| 1748 |
case 2: /* far jmp */ |
| 1749 |
bad_opcode(name, op); |
| 1750 |
break; |
| 1751 |
case 3: /* short jmp */ |
| 1752 |
immed = 1; |
| 1753 |
is_jmp = 1; |
| 1754 |
break; |
| 1755 |
} |
| 1756 |
break; |
| 1757 |
case 3: /* in/out register */ |
| 1758 |
break; |
| 1759 |
} |
| 1760 |
modrm = 0; |
| 1761 |
break; |
| 1762 |
|
| 1763 |
case 15: |
| 1764 |
switch ((op & 0xe) >> 1) { |
| 1765 |
case 0: |
| 1766 |
case 1: |
| 1767 |
is_prefix = 1; |
| 1768 |
break; |
| 1769 |
case 2: |
| 1770 |
case 4: |
| 1771 |
case 5: |
| 1772 |
case 6: |
| 1773 |
modrm = 0; |
| 1774 |
/* Some privileged insns are used as markers. */ |
| 1775 |
switch (op) { |
| 1776 |
case 0xf4: /* hlt: Exit translation block. */ |
| 1777 |
is_exit = 1; |
| 1778 |
break; |
| 1779 |
case 0xfa: /* cli: Jump to label. */ |
| 1780 |
is_exit = 1; |
| 1781 |
immed = 4; |
| 1782 |
break; |
| 1783 |
case 0xfb: /* sti: TB patch jump. */ |
| 1784 |
/* Mark the insn for patching, but continue sscanning. */ |
| 1785 |
flags[insn] |= FLAG_EXIT; |
| 1786 |
immed = 4; |
| 1787 |
break; |
| 1788 |
} |
| 1789 |
break; |
| 1790 |
case 3: /* unary grp3 */ |
| 1791 |
if ((ptr[insn_size] & 0x38) == 0) { |
| 1792 |
if (op == 0xf7) |
| 1793 |
immed = op_size; |
| 1794 |
else |
| 1795 |
immed = 1; /* test immediate */ |
| 1796 |
} |
| 1797 |
break; |
| 1798 |
case 7: /* inc/dec grp4/5 */ |
| 1799 |
/* TODO: This includes indirect jumps. We should fail if we |
| 1800 |
encounter one of these. */ |
| 1801 |
break; |
| 1802 |
} |
| 1803 |
break; |
| 1804 |
} |
| 1805 |
} |
| 1806 |
|
| 1807 |
if (modrm) { |
| 1808 |
if (addr_size != 4) |
| 1809 |
error("16-bit addressing mode used in %s", name); |
| 1810 |
|
| 1811 |
disp = 0; |
| 1812 |
modrm = ptr[insn_size]; |
| 1813 |
insn_size = eat_bytes(name, flags, insn, insn_size, 1); |
| 1814 |
modrm &= 0xc7; |
| 1815 |
switch ((modrm & 0xc0) >> 6) { |
| 1816 |
case 0: |
| 1817 |
if (modrm == 5) |
| 1818 |
disp = 4; |
| 1819 |
break; |
| 1820 |
case 1: |
| 1821 |
disp = 1; |
| 1822 |
break; |
| 1823 |
case 2: |
| 1824 |
disp = 4; |
| 1825 |
break; |
| 1826 |
} |
| 1827 |
if ((modrm & 0xc0) != 0xc0 && (modrm & 0x7) == 4) { |
| 1828 |
/* SIB byte */ |
| 1829 |
if (modrm == 4 && (ptr[insn_size] & 0x7) == 5) { |
| 1830 |
disp = 4; |
| 1831 |
is_pcrel = 1; |
| 1832 |
} |
| 1833 |
insn_size = eat_bytes(name, flags, insn, insn_size, 1); |
| 1834 |
} |
| 1835 |
insn_size = eat_bytes(name, flags, insn, insn_size, disp); |
| 1836 |
} |
| 1837 |
insn_size = eat_bytes(name, flags, insn, insn_size, immed); |
| 1838 |
if (is_condjmp || is_jmp) { |
| 1839 |
if (immed == 1) { |
| 1840 |
disp = (int8_t)*(ptr + insn_size - 1); |
| 1841 |
} else { |
| 1842 |
disp = (((int32_t)*(ptr + insn_size - 1)) << 24) |
| 1843 |
| (((int32_t)*(ptr + insn_size - 2)) << 16) |
| 1844 |
| (((int32_t)*(ptr + insn_size - 3)) << 8) |
| 1845 |
| *(ptr + insn_size - 4); |
| 1846 |
} |
| 1847 |
disp += insn_size; |
| 1848 |
/* Jumps to external symbols point to the address of the offset |
| 1849 |
before relocation. */ |
| 1850 |
/* ??? These are probably a tailcall. We could fix them up by |
| 1851 |
replacing them with jmp to EOB + call, but it's easier to just |
| 1852 |
prevent the compiler generating them. */ |
| 1853 |
if (disp == 1) |
| 1854 |
error("Unconditional jump (sibcall?) in %s", name); |
| 1855 |
disp += insn; |
| 1856 |
if (disp < 0 || disp > len) |
| 1857 |
error("Jump outside instruction in %s", name); |
| 1858 |
|
| 1859 |
if ((flags[disp] & (FLAG_INSN | FLAG_SCANNED)) == FLAG_SCANNED) |
| 1860 |
error("Overlapping instructions in %s", name); |
| 1861 |
|
| 1862 |
flags[disp] |= (FLAG_INSN | FLAG_TARGET); |
| 1863 |
is_pcrel = 1; |
| 1864 |
} |
| 1865 |
if (is_pcrel) { |
| 1866 |
/* Mark the following insn as a jump target. This will stop |
| 1867 |
this instruction being moved. */ |
| 1868 |
flags[insn + insn_size] |= FLAG_TARGET; |
| 1869 |
} |
| 1870 |
if (is_ret) |
| 1871 |
flags[insn] |= FLAG_RET; |
| 1872 |
|
| 1873 |
if (is_exit) |
| 1874 |
flags[insn] |= FLAG_EXIT; |
| 1875 |
|
| 1876 |
if (is_stack) |
| 1877 |
flags[insn] |= FLAG_STACK; |
| 1878 |
|
| 1879 |
if (!(is_jmp || is_ret || is_exit)) |
| 1880 |
flags[insn + insn_size] |= FLAG_INSN; |
| 1881 |
} |
| 1882 |
|
| 1883 |
/* Scan a function body. Returns the position of the return sequence. |
| 1884 |
Sets *patch_bytes to the number of bytes that need to be copied from that |
| 1885 |
location. If no patching is required (ie. the return is the last insn) |
| 1886 |
*patch_bytes will be set to -1. *plen is the number of code bytes to copy. |
| 1887 |
*/ |
| 1888 |
static int trace_i386_op(const char * name, uint8_t *start_p, int *plen, |
| 1889 |
int *patch_bytes, int *exit_addrs) |
| 1890 |
{ |
| 1891 |
char *flags; |
| 1892 |
int more; |
| 1893 |
int insn; |
| 1894 |
int retpos; |
| 1895 |
int bytes; |
| 1896 |
int num_exits; |
| 1897 |
int len; |
| 1898 |
int last_insn; |
| 1899 |
int stack_clobbered; |
| 1900 |
|
| 1901 |
len = *plen; |
| 1902 |
flags = malloc(len + 1); |
| 1903 |
memset(flags, 0, len + 1); |
| 1904 |
flags[0] |= FLAG_INSN; |
| 1905 |
more = 1; |
| 1906 |
while (more) { |
| 1907 |
more = 0; |
| 1908 |
for (insn = 0; insn < len; insn++) { |
| 1909 |
if ((flags[insn] & (FLAG_INSN | FLAG_SCANNED)) == FLAG_INSN) { |
| 1910 |
trace_i386_insn(name, start_p, flags, insn, len); |
| 1911 |
more = 1; |
| 1912 |
} |
| 1913 |
} |
| 1914 |
} |
| 1915 |
|
| 1916 |
/* Strip any unused code at the end of the function. */ |
| 1917 |
while (len > 0 && flags[len - 1] == 0) |
| 1918 |
len--; |
| 1919 |
|
| 1920 |
retpos = -1; |
| 1921 |
num_exits = 0; |
| 1922 |
last_insn = 0; |
| 1923 |
stack_clobbered = 0; |
| 1924 |
for (insn = 0; insn < len; insn++) { |
| 1925 |
if (flags[insn] & FLAG_RET) { |
| 1926 |
/* ??? In theory it should be possible to handle multiple return |
| 1927 |
points. In practice it's not worth the effort. */ |
| 1928 |
if (retpos != -1) |
| 1929 |
error("Multiple return instructions in %s", name); |
| 1930 |
retpos = insn; |
| 1931 |
} |
| 1932 |
if (flags[insn] & FLAG_EXIT) { |
| 1933 |
if (stack_clobbered) |
| 1934 |
error("Stack clobbered in %s", name); |
| 1935 |
if (num_exits == MAX_EXITS) |
| 1936 |
error("Too many block exits in %s", name); |
| 1937 |
exit_addrs[num_exits] = insn; |
| 1938 |
num_exits++; |
| 1939 |
} |
| 1940 |
if (flags[insn] & FLAG_INSN) |
| 1941 |
last_insn = insn; |
| 1942 |
if (flags[insn] & FLAG_STACK) |
| 1943 |
stack_clobbered = 1; |
| 1944 |
} |
| 1945 |
|
| 1946 |
exit_addrs[num_exits] = -1; |
| 1947 |
if (retpos == -1) { |
| 1948 |
if (num_exits == 0) { |
| 1949 |
error ("No return instruction found in %s", name); |
| 1950 |
} else { |
| 1951 |
retpos = len; |
| 1952 |
last_insn = len; |
| 1953 |
} |
| 1954 |
} |
| 1955 |
|
| 1956 |
/* If the return instruction is the last instruction we can just |
| 1957 |
remove it. */ |
| 1958 |
if (retpos == last_insn) |
| 1959 |
*patch_bytes = -1; |
| 1960 |
else |
| 1961 |
*patch_bytes = 0; |
| 1962 |
|
| 1963 |
/* Back up over any nop instructions. */ |
| 1964 |
while (retpos > 0 |
| 1965 |
&& (flags[retpos] & FLAG_TARGET) == 0 |
| 1966 |
&& (flags[retpos - 1] & FLAG_INSN) != 0 |
| 1967 |
&& start_p[retpos - 1] == 0x90) { |
| 1968 |
retpos--; |
| 1969 |
} |
| 1970 |
|
| 1971 |
if (*patch_bytes == -1) { |
| 1972 |
*plen = retpos; |
| 1973 |
free (flags); |
| 1974 |
return retpos; |
| 1975 |
} |
| 1976 |
*plen = len; |
| 1977 |
|
| 1978 |
/* The ret is in the middle of the function. Find four more bytes that |
| 1979 |
so the ret can be replaced by a jmp. */ |
| 1980 |
/* ??? Use a short jump where possible. */ |
| 1981 |
bytes = 4; |
| 1982 |
insn = retpos + 1; |
| 1983 |
/* We can clobber everything up to the next jump target. */ |
| 1984 |
while (insn < len && bytes > 0 && (flags[insn] & FLAG_TARGET) == 0) { |
| 1985 |
insn++; |
| 1986 |
bytes--; |
| 1987 |
} |
| 1988 |
if (bytes > 0) { |
| 1989 |
/* ???: Strip out nop blocks. */ |
| 1990 |
/* We can't do the replacement without clobbering anything important. |
| 1991 |
Copy preceeding instructions(s) to give us some space. */ |
| 1992 |
while (retpos > 0) { |
| 1993 |
/* If this byte is the target of a jmp we can't move it. */ |
| 1994 |
if (flags[retpos] & FLAG_TARGET) |
| 1995 |
break; |
| 1996 |
|
| 1997 |
(*patch_bytes)++; |
| 1998 |
bytes--; |
| 1999 |
retpos--; |
| 2000 |
|
| 2001 |
/* Break out of the loop if we have enough space and this is either |
| 2002 |
the first byte of an instruction or a pad byte. */ |
| 2003 |
if ((flags[retpos] & (FLAG_INSN | FLAG_SCANNED)) != FLAG_SCANNED |
| 2004 |
&& bytes <= 0) { |
| 2005 |
break; |
| 2006 |
} |
| 2007 |
} |
| 2008 |
} |
| 2009 |
|
| 2010 |
if (bytes > 0) |
| 2011 |
error("Unable to replace ret with jmp in %s\n", name); |
| 2012 |
|
| 2013 |
free(flags); |
| 2014 |
return retpos; |
| 2015 |
} |
| 2016 |
|
| 2017 |
#endif |
| 2018 |
|
| 1346 |
#define MAX_ARGS 3 |
2019 |
#define MAX_ARGS 3 |
| 1347 |
|
2020 |
|
| 1348 |
/* generate op code */ |
2021 |
/* generate op code */ |
|
Lines 1356-1361
Link Here
|
| 1356 |
uint8_t args_present[MAX_ARGS]; |
2029 |
uint8_t args_present[MAX_ARGS]; |
| 1357 |
const char *sym_name, *p; |
2030 |
const char *sym_name, *p; |
| 1358 |
EXE_RELOC *rel; |
2031 |
EXE_RELOC *rel; |
|
|
2032 |
#if defined(HOST_I386) || defined(HOST_X86_64) |
| 2033 |
int patch_bytes; |
| 2034 |
int retpos; |
| 2035 |
int exit_addrs[MAX_EXITS]; |
| 2036 |
#endif |
| 1359 |
|
2037 |
|
| 1360 |
/* Compute exact size excluding prologue and epilogue instructions. |
2038 |
/* Compute exact size excluding prologue and epilogue instructions. |
| 1361 |
* Increment start_offset to skip epilogue instructions, then compute |
2039 |
* Increment start_offset to skip epilogue instructions, then compute |
|
Lines 1366-1398
Link Here
|
| 1366 |
p_end = p_start + size; |
2044 |
p_end = p_start + size; |
| 1367 |
start_offset = offset; |
2045 |
start_offset = offset; |
| 1368 |
#if defined(HOST_I386) || defined(HOST_X86_64) |
2046 |
#if defined(HOST_I386) || defined(HOST_X86_64) |
| 1369 |
#ifdef CONFIG_FORMAT_COFF |
|
|
| 1370 |
{ |
| 1371 |
uint8_t *p; |
| 1372 |
p = p_end - 1; |
| 1373 |
if (p == p_start) |
| 1374 |
error("empty code for %s", name); |
| 1375 |
while (*p != 0xc3) { |
| 1376 |
p--; |
| 1377 |
if (p <= p_start) |
| 1378 |
error("ret or jmp expected at the end of %s", name); |
| 1379 |
} |
| 1380 |
copy_size = p - p_start; |
| 1381 |
} |
| 1382 |
#else |
| 1383 |
{ |
2047 |
{ |
| 1384 |
int len; |
2048 |
int len; |
| 1385 |
len = p_end - p_start; |
2049 |
len = p_end - p_start; |
| 1386 |
if (len == 0) |
2050 |
retpos = trace_i386_op(name, p_start, &len, &patch_bytes, exit_addrs); |
| 1387 |
error("empty code for %s", name); |
|
|
| 1388 |
if (p_end[-1] == 0xc3) { |
| 1389 |
len--; |
| 1390 |
} else { |
| 1391 |
error("ret or jmp expected at the end of %s", name); |
| 1392 |
} |
| 1393 |
copy_size = len; |
2051 |
copy_size = len; |
| 1394 |
} |
2052 |
} |
| 1395 |
#endif |
|
|
| 1396 |
#elif defined(HOST_PPC) |
2053 |
#elif defined(HOST_PPC) |
| 1397 |
{ |
2054 |
{ |
| 1398 |
uint8_t *p; |
2055 |
uint8_t *p; |
|
Lines 1596-1601
Link Here
|
| 1596 |
} |
2253 |
} |
| 1597 |
|
2254 |
|
| 1598 |
if (gen_switch == 2) { |
2255 |
if (gen_switch == 2) { |
|
|
2256 |
#if defined(HOST_I386) || defined(HOST_X86_64) |
| 2257 |
if (patch_bytes != -1) |
| 2258 |
copy_size += patch_bytes; |
| 2259 |
#ifdef DEBUG_OP |
| 2260 |
copy_size += 2; |
| 2261 |
#endif |
| 2262 |
#endif |
| 1599 |
fprintf(outfile, "DEF(%s, %d, %d)\n", name + 3, nb_args, copy_size); |
2263 |
fprintf(outfile, "DEF(%s, %d, %d)\n", name + 3, nb_args, copy_size); |
| 1600 |
} else if (gen_switch == 1) { |
2264 |
} else if (gen_switch == 1) { |
| 1601 |
|
2265 |
|
|
Lines 1800-1806
Link Here
|
| 1800 |
#error unsupport object format |
2464 |
#error unsupport object format |
| 1801 |
#endif |
2465 |
#endif |
| 1802 |
} |
2466 |
} |
|
|
2467 |
} |
| 2468 |
/* Replace the marker instructions with the actual opcodes. */ |
| 2469 |
for (i = 0; exit_addrs[i] != -1; i++) { |
| 2470 |
int op; |
| 2471 |
switch (p_start[exit_addrs[i]]) |
| 2472 |
{ |
| 2473 |
case 0xf4: op = 0xc3; break; /* hlt -> ret */ |
| 2474 |
case 0xfa: op = 0xe9; break; /* cli -> jmp */ |
| 2475 |
case 0xfb: op = 0xe9; break; /* sti -> jmp */ |
| 2476 |
default: error("Internal error"); |
| 2477 |
} |
| 2478 |
fprintf(outfile, |
| 2479 |
" *(uint8_t *)(gen_code_ptr + %d) = 0x%x;\n", |
| 2480 |
exit_addrs[i], op); |
| 1803 |
} |
2481 |
} |
|
|
2482 |
/* Fix up the return instruction. */ |
| 2483 |
if (patch_bytes != -1) { |
| 2484 |
if (patch_bytes) { |
| 2485 |
fprintf(outfile, " memcpy(gen_code_ptr + %d," |
| 2486 |
"gen_code_ptr + %d, %d);\n", |
| 2487 |
copy_size, retpos, patch_bytes); |
| 2488 |
} |
| 2489 |
fprintf(outfile, |
| 2490 |
" *(uint8_t *)(gen_code_ptr + %d) = 0xe9;\n", |
| 2491 |
retpos); |
| 2492 |
fprintf(outfile, |
| 2493 |
" *(uint32_t *)(gen_code_ptr + %d) = 0x%x;\n", |
| 2494 |
retpos + 1, copy_size - (retpos + 5)); |
| 2495 |
|
| 2496 |
copy_size += patch_bytes; |
| 2497 |
} |
| 2498 |
#ifdef DEBUG_OP |
| 2499 |
fprintf(outfile, |
| 2500 |
" *(uint16_t *)(gen_code_ptr + %d) = 0x9090;\n", |
| 2501 |
copy_size); |
| 2502 |
copy_size += 2; |
| 2503 |
#endif |
| 1804 |
} |
2504 |
} |
| 1805 |
#elif defined(HOST_X86_64) |
2505 |
#elif defined(HOST_X86_64) |
| 1806 |
{ |
2506 |
{ |
|
Lines 1834-1839
Link Here
|
| 1834 |
} |
2534 |
} |
| 1835 |
} |
2535 |
} |
| 1836 |
} |
2536 |
} |
|
|
2537 |
/* Replace the marker instructions with the actual opcodes. */ |
| 2538 |
for (i = 0; exit_addrs[i] != -1; i++) { |
| 2539 |
int op; |
| 2540 |
switch (p_start[exit_addrs[i]]) |
| 2541 |
{ |
| 2542 |
case 0xf4: op = 0xc3; break; /* hlt -> ret */ |
| 2543 |
case 0xfa: op = 0xe9; break; /* cli -> jmp */ |
| 2544 |
case 0xfb: op = 0xe9; break; /* sti -> jmp */ |
| 2545 |
default: error("Internal error"); |
| 2546 |
} |
| 2547 |
fprintf(outfile, |
| 2548 |
" *(uint8_t *)(gen_code_ptr + %d) = 0x%x;\n", |
| 2549 |
exit_addrs[i], op); |
| 2550 |
} |
| 2551 |
/* Fix up the return instruction. */ |
| 2552 |
if (patch_bytes != -1) { |
| 2553 |
if (patch_bytes) { |
| 2554 |
fprintf(outfile, " memcpy(gen_code_ptr + %d," |
| 2555 |
"gen_code_ptr + %d, %d);\n", |
| 2556 |
copy_size, retpos, patch_bytes); |
| 2557 |
} |
| 2558 |
fprintf(outfile, |
| 2559 |
" *(uint8_t *)(gen_code_ptr + %d) = 0xe9;\n", |
| 2560 |
retpos); |
| 2561 |
fprintf(outfile, |
| 2562 |
" *(uint32_t *)(gen_code_ptr + %d) = 0x%x;\n", |
| 2563 |
retpos + 1, copy_size - (retpos + 5)); |
| 2564 |
|
| 2565 |
copy_size += patch_bytes; |
| 2566 |
} |
| 2567 |
#ifdef DEBUG_OP |
| 2568 |
fprintf(outfile, |
| 2569 |
" *(uint16_t *)(gen_code_ptr + %d) = 0x9090;\n", |
| 2570 |
copy_size); |
| 2571 |
copy_size += 2; |
| 2572 |
#endif |
| 1837 |
} |
2573 |
} |
| 1838 |
#elif defined(HOST_PPC) |
2574 |
#elif defined(HOST_PPC) |
| 1839 |
{ |
2575 |
{ |
