mirror of
https://github.com/RPCS3/llvm.git
synced 2025-04-15 04:20:27 +00:00
c4ffb0705d
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358197 91177308-0d34-0410-b5e6-96231b3b80d8
262 lines
7.3 KiB
ReStructuredText
262 lines
7.3 KiB
ReStructuredText
=====================================
|
|
CodeView Type Records
|
|
=====================================
|
|
|
|
|
|
.. contents::
|
|
:local:
|
|
|
|
.. _types_intro:
|
|
|
|
Introduction
|
|
============
|
|
|
|
This document describes the usage and serialization format of the various
|
|
CodeView type records that LLVM understands. This document does not describe
|
|
every single CodeView type record that is defined. In some cases, this is
|
|
because the records are clearly deprecated and can only appear in very old
|
|
software (e.g. the 16-bit types). On other cases, it is because the records
|
|
have never been observed in practice. This could be because they are only
|
|
generated for non-C++ code (e.g. Visual Basic, C#), or because they have been
|
|
made obsolete by newer records, or any number of other reasons. However, the
|
|
records we describe here should cover 99% of type records that one can expect
|
|
to encounter when dealing with modern C++ toolchains.
|
|
|
|
Record Categories
|
|
=================
|
|
|
|
We can think of a sequence of CodeView type records as an array of variable length
|
|
`leaf records`. Each such record describes its own length as part of a fixed-size
|
|
header, as well as the kind of record it is. Leaf records are either padded to 4
|
|
bytes (if this type stream appears in a TPI/IPI stream of a PDB) or not padded at
|
|
all (if this type stream appears in the ``.debug$T`` section of an object file).
|
|
Padding is implemented by inserting a decreasing sequence of `<_padding_records>`
|
|
that terminates with ``LF_PAD0``.
|
|
|
|
The final category of record is a ``member record``. One particular leaf type --
|
|
``LF_FIELDLIST`` -- contains a series of embedded records. While the outer
|
|
``LF_FIELDLIST`` describes its length (like any other leaf record), the embedded
|
|
records -- called ``member records`` do not.
|
|
|
|
.. _leaf_types:
|
|
|
|
Leaf Records
|
|
------------
|
|
|
|
All leaf records begin with the following 4 byte prefix:
|
|
|
|
.. code-block:: c++
|
|
|
|
struct RecordHeader {
|
|
uint16_t RecordLen; // Record length, not including this 2 byte field.
|
|
uint16_t RecordKind; // Record kind enum.
|
|
};
|
|
|
|
LF_POINTER (0x1002)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
**Usage:** Describes a pointer to another type.
|
|
|
|
**Layout:**
|
|
|
|
.. code-block:: none
|
|
|
|
.--------------------.-- +0
|
|
| Referent Type |
|
|
.--------------------.-- +4
|
|
| Attributes |
|
|
.--------------------.-- +8
|
|
| Member Ptr Info | Only present if |Attributes| indicates this is a member pointer.
|
|
.--------------------.-- +E
|
|
|
|
Attributes is a bitfield with the following layout:
|
|
|
|
.. code-block:: none
|
|
|
|
.-----------------------------------------------------------------------------------------------------.
|
|
| Unused | Flags | Size | Modifiers | Mode | Kind |
|
|
.-----------------------------------------------------------------------------------------------------.
|
|
| | | | | | |
|
|
0x100 +0x16 +0x13 +0xD +0x8 +0x5 +0x0
|
|
|
|
where the various fields are defined by the following enums:
|
|
|
|
.. code-block:: c++
|
|
|
|
enum class PointerKind : uint8_t {
|
|
Near16 = 0x00, // 16 bit pointer
|
|
Far16 = 0x01, // 16:16 far pointer
|
|
Huge16 = 0x02, // 16:16 huge pointer
|
|
BasedOnSegment = 0x03, // based on segment
|
|
BasedOnValue = 0x04, // based on value of base
|
|
BasedOnSegmentValue = 0x05, // based on segment value of base
|
|
BasedOnAddress = 0x06, // based on address of base
|
|
BasedOnSegmentAddress = 0x07, // based on segment address of base
|
|
BasedOnType = 0x08, // based on type
|
|
BasedOnSelf = 0x09, // based on self
|
|
Near32 = 0x0a, // 32 bit pointer
|
|
Far32 = 0x0b, // 16:32 pointer
|
|
Near64 = 0x0c // 64 bit pointer
|
|
};
|
|
enum class PointerMode : uint8_t {
|
|
Pointer = 0x00, // "normal" pointer
|
|
LValueReference = 0x01, // "old" reference
|
|
PointerToDataMember = 0x02, // pointer to data member
|
|
PointerToMemberFunction = 0x03, // pointer to member function
|
|
RValueReference = 0x04 // r-value reference
|
|
};
|
|
enum class PointerModifiers : uint8_t {
|
|
None = 0x00, // "normal" pointer
|
|
Flat32 = 0x01, // "flat" pointer
|
|
Volatile = 0x02, // pointer is marked volatile
|
|
Const = 0x04, // pointer is marked const
|
|
Unaligned = 0x08, // pointer is marked unaligned
|
|
Restrict = 0x10, // pointer is marked restrict
|
|
};
|
|
enum class PointerFlags : uint8_t {
|
|
WinRTSmartPointer = 0x01, // pointer is a WinRT smart pointer
|
|
LValueRefThisPointer = 0x02, // pointer is a 'this' pointer of a member function with ref qualifier (e.g. void X::foo() &)
|
|
RValueRefThisPointer = 0x04 // pointer is a 'this' pointer of a member function with ref qualifier (e.g. void X::foo() &&)
|
|
};
|
|
|
|
The ``Size`` field of the Attributes bitmask is a 1-byte value indicating the
|
|
pointer size. For example, a `void*` would have a size of either 4 or 8 depending
|
|
on the target architecture. On the other hand, if ``Mode`` indicates that this is
|
|
a pointer to member function or pointer to data member, then the size can be any
|
|
implementation defined number.
|
|
|
|
The ``Member Ptr Info`` field of the ``LF_POINTER`` record is only present if the
|
|
attributes indicate that this is a pointer to member.
|
|
|
|
Note that "plain" pointers to primitive types are not represented by ``LF_POINTER``
|
|
records, they are indicated by special reserved :ref:`TypeIndex values <type_indices>`.
|
|
|
|
|
|
|
|
LF_MODIFIER (0x1001)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_PROCEDURE (0x1008)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_MFUNCTION (0x1009)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_LABEL (0x000e)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ARGLIST (0x1201)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_FIELDLIST (0x1203)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ARRAY (0x1503)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
LF_CLASS (0x1504)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
LF_STRUCTURE (0x1505)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_INTERFACE (0x1519)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_UNION (0x1506)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ENUM (0x1507)
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
LF_TYPESERVER2 (0x1515)
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_VFTABLE (0x151d)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_VTSHAPE (0x000a)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_BITFIELD (0x1205)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_FUNC_ID (0x1601)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_MFUNC_ID (0x1602)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_BUILDINFO (0x1603)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_SUBSTR_LIST (0x1604)
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_STRING_ID (0x1605)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_UDT_SRC_LINE (0x1606)
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_UDT_MOD_SRC_LINE (0x1607)
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_METHODLIST (0x1206)
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_PRECOMP (0x1509)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ENDPRECOMP (0x0014)
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
.. _member_types:
|
|
|
|
Member Records
|
|
--------------
|
|
|
|
LF_BCLASS (0x1400)
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_BINTERFACE (0x151a)
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_VBCLASS (0x1401)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_IVBCLASS (0x1402)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_VFUNCTAB (0x1409)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_STMEMBER (0x150e)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_METHOD (0x150f)
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_MEMBER (0x150d)
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_NESTTYPE (0x1510)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ONEMETHOD (0x1511)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_ENUMERATE (0x1502)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
LF_INDEX (0x1404)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
.. _padding_records:
|
|
|
|
Padding Records
|
|
---------------
|
|
|
|
LF_PADn (0xf0 + n)
|
|
^^^^^^^^^^^^^^^^^^
|