...
}
-<a name="LLVMDebugVersion">The first field of a descriptor is always an
-``i32`` containing a tag value identifying the content of the descriptor.
-The remaining fields are specific to the descriptor. The values of tags are
-loosely bound to the tag values of DWARF information entries. However, that
-does not restrict the use of the information supplied to DWARF targets.
+Most of the string and integer fields in descriptors are packed into a single,
+null-separated ``mdstring``. The first field of the header is always an
+``i32`` containing the DWARF tag value identifying the content of the
+descriptor.
+
+For clarity of definition in this document, these header fields are described
+below split inside an imaginary ``DIHeader`` construct. This is invalid
+assembly syntax. In valid IR, these fields are stringified and concatenated,
+separated by ``\00``.
The details of the various descriptors follow.
.. code-block:: llvm
!0 = metadata !{
- i32, ;; Tag = 17 (DW_TAG_compile_unit)
+ DIHeader(
+ i32, ;; Tag = 17 (DW_TAG_compile_unit)
+ i32, ;; DWARF language identifier (ex. DW_LANG_C89)
+ mdstring, ;; Producer (ex. "4.0.1 LLVM (LLVM research group)")
+ i1, ;; True if this is optimized.
+ mdstring, ;; Flags
+ i32, ;; Runtime version
+ mdstring, ;; Split debug filename
+ i32 ;; Debug info emission kind (1 = Full Debug Info, 2 = Line Tables Only)
+ ),
metadata, ;; Source directory (including trailing slash) & file pair
- i32, ;; DWARF language identifier (ex. DW_LANG_C89)
- metadata ;; Producer (ex. "4.0.1 LLVM (LLVM research group)")
- i1, ;; True if this is optimized.
- metadata, ;; Flags
- i32 ;; Runtime version
- metadata ;; List of enums types
- metadata ;; List of retained types
- metadata ;; List of subprograms
- metadata ;; List of global variables
+ metadata, ;; List of enums types
+ metadata, ;; List of retained types
+ metadata, ;; List of subprograms
+ metadata, ;; List of global variables
metadata ;; List of imported entities
- metadata ;; Split debug filename
- i32 ;; Debug info emission kind (1 = Full Debug Info, 2 = Line Tables Only)
}
These descriptors contain a source language ID for the file (we use the DWARF
.. code-block:: llvm
!0 = metadata !{
- i32, ;; Tag = 41 (DW_TAG_file_type)
- metadata, ;; Source directory (including trailing slash) & file pair
+ DIHeader(
+ i32 ;; Tag = 41 (DW_TAG_file_type)
+ ),
+ metadata ;; Source directory (including trailing slash) & file pair
}
These descriptors contain information for a file. Global variables and top
.. code-block:: llvm
!1 = metadata !{
- i32, ;; Tag = 52 (DW_TAG_variable)
- i32, ;; Unused field.
+ DIHeader(
+ i32, ;; Tag = 52 (DW_TAG_variable)
+ mdstring, ;; Name
+ mdstring, ;; Display name (fully qualified C++ name)
+ mdstring, ;; MIPS linkage name (for C++)
+ i32, ;; Line number where defined
+ i1, ;; True if the global is local to compile unit (static)
+ i1 ;; True if the global is defined in the compile unit (not extern)
+ ),
metadata, ;; Reference to context descriptor
- metadata, ;; Name
- metadata, ;; Display name (fully qualified C++ name)
- metadata, ;; MIPS linkage name (for C++)
metadata, ;; Reference to file where defined
- i32, ;; Line number where defined
metadata, ;; Reference to type descriptor
- i1, ;; True if the global is local to compile unit (static)
- i1, ;; True if the global is defined in the compile unit (not extern)
{}*, ;; Reference to the global variable
metadata, ;; The static member declaration, if any
}
.. code-block:: llvm
!2 = metadata !{
- i32, ;; Tag = 46 (DW_TAG_subprogram)
+ DIHeader(
+ i32, ;; Tag = 46 (DW_TAG_subprogram)
+ mdstring, ;; Name
+ mdstring, ;; Display name (fully qualified C++ name)
+ mdstring, ;; MIPS linkage name (for C++)
+ i32, ;; Line number where defined
+ i1, ;; True if the global is local to compile unit (static)
+ i1, ;; True if the global is defined in the compile unit (not extern)
+ i32, ;; Virtuality, e.g. dwarf::DW_VIRTUALITY__virtual
+ i32, ;; Index into a virtual function
+ i32, ;; Flags - Artificial, Private, Protected, Explicit, Prototyped.
+ i1, ;; isOptimized
+ i32 ;; Line number where the scope of the subprogram begins
+ ),
metadata, ;; Source directory (including trailing slash) & file pair
metadata, ;; Reference to context descriptor
- metadata, ;; Name
- metadata, ;; Display name (fully qualified C++ name)
- metadata, ;; MIPS linkage name (for C++)
- i32, ;; Line number where defined
metadata, ;; Reference to type descriptor
- i1, ;; True if the global is local to compile unit (static)
- i1, ;; True if the global is defined in the compile unit (not extern)
- i32, ;; Virtuality, e.g. dwarf::DW_VIRTUALITY__virtual
- i32, ;; Index into a virtual function
metadata, ;; indicates which base type contains the vtable pointer for the
;; derived class
- i32, ;; Flags - Artificial, Private, Protected, Explicit, Prototyped.
- i1, ;; isOptimized
{}*, ;; Reference to the LLVM function
metadata, ;; Lists function template parameters
metadata, ;; Function declaration descriptor
- metadata, ;; List of function variables
- i32 ;; Line number where the scope of the subprogram begins
+ metadata ;; List of function variables
}
These descriptors provide debug information about functions, methods and
.. code-block:: llvm
!3 = metadata !{
- i32, ;; Tag = 11 (DW_TAG_lexical_block)
+ DIHeader(
+ i32, ;; Tag = 11 (DW_TAG_lexical_block)
+ i32, ;; Line number
+ i32, ;; Column number
+ i32 ;; Unique ID to identify blocks from a template function
+ ),
metadata, ;; Source directory (including trailing slash) & file pair
- metadata, ;; Reference to context descriptor
- i32, ;; Line number
- i32, ;; Column number
- i32 ;; Unique ID to identify blocks from a template function
+ metadata ;; Reference to context descriptor
}
This descriptor provides debug information about nested blocks within a
.. code-block:: llvm
!3 = metadata !{
- i32, ;; Tag = 11 (DW_TAG_lexical_block)
+ DIHeader(
+ i32, ;; Tag = 11 (DW_TAG_lexical_block)
+ i32 ;; DWARF path discriminator value
+ ),
metadata, ;; Source directory (including trailing slash) & file pair
metadata ;; Reference to the scope we're annotating with a file change
- i32, ;; DWARF path discriminator value
}
This descriptor provides a wrapper around a lexical scope to handle file
.. code-block:: llvm
!4 = metadata !{
- i32, ;; Tag = 36 (DW_TAG_base_type)
+ DIHeader(
+ i32, ;; Tag = 36 (DW_TAG_base_type)
+ mdstring, ;; Name (may be "" for anonymous types)
+ i32, ;; Line number where defined (may be 0)
+ i64, ;; Size in bits
+ i64, ;; Alignment in bits
+ i64, ;; Offset in bits
+ i32, ;; Flags
+ i32 ;; DWARF type encoding
+ ),
metadata, ;; Source directory (including trailing slash) & file pair (may be null)
- metadata, ;; Reference to context
- metadata, ;; Name (may be "" for anonymous types)
- i32, ;; Line number where defined (may be 0)
- i64, ;; Size in bits
- i64, ;; Alignment in bits
- i64, ;; Offset in bits
- i32, ;; Flags
- i32 ;; DWARF type encoding
+ metadata ;; Reference to context
}
These descriptors define primitive types used in the code. Example ``int``,
.. code-block:: llvm
!5 = metadata !{
- i32, ;; Tag (see below)
+ DIHeader(
+ i32, ;; Tag (see below)
+ mdstring, ;; Name (may be "" for anonymous types)
+ i32, ;; Line number where defined (may be 0)
+ i64, ;; Size in bits
+ i64, ;; Alignment in bits
+ i64, ;; Offset in bits
+ i32 ;; Flags to encode attributes, e.g. private
+ ),
metadata, ;; Source directory (including trailing slash) & file pair (may be null)
metadata, ;; Reference to context
- metadata, ;; Name (may be "" for anonymous types)
- i32, ;; Line number where defined (may be 0)
- i64, ;; Size in bits
- i64, ;; Alignment in bits
- i64, ;; Offset in bits
- i32, ;; Flags to encode attributes, e.g. private
metadata, ;; Reference to type derived from
- metadata, ;; (optional) Name of the Objective C property associated with
- ;; Objective-C an ivar, or the type of which this
- ;; pointer-to-member is pointing to members of.
- metadata, ;; (optional) Name of the Objective C property getter selector.
- metadata, ;; (optional) Name of the Objective C property setter selector.
- i32 ;; (optional) Objective C property attributes.
+ metadata ;; (optional) Objective C property node
}
These descriptors are used to define types derived from other types. The value
.. code-block:: llvm
!6 = metadata !{
- i32, ;; Tag (see below)
+ DIHeader(
+ i32, ;; Tag (see below)
+ mdstring, ;; Name (may be "" for anonymous types)
+ i32, ;; Line number where defined (may be 0)
+ i64, ;; Size in bits
+ i64, ;; Alignment in bits
+ i64, ;; Offset in bits
+ i32, ;; Flags
+ i32 ;; Runtime languages
+ ),
metadata, ;; Source directory (including trailing slash) & file pair (may be null)
metadata, ;; Reference to context
- metadata, ;; Name (may be "" for anonymous types)
- i32, ;; Line number where defined (may be 0)
- i64, ;; Size in bits
- i64, ;; Alignment in bits
- i64, ;; Offset in bits
- i32, ;; Flags
metadata, ;; Reference to type derived from
metadata, ;; Reference to array of member descriptors
- i32, ;; Runtime languages
metadata, ;; Base type containing the vtable pointer for this type
metadata, ;; Template parameters
- metadata ;; A unique identifier for type uniquing purpose (may be null)
+ mdstring ;; A unique identifier for type uniquing purpose (may be null)
}
These descriptors are used to define types that are composed of 0 or more
.. code-block:: llvm
!42 = metadata !{
- i32, ;; Tag = 33 (DW_TAG_subrange_type)
- i64, ;; Low value
- i64 ;; High value
+ DIHeader(
+ i32, ;; Tag = 33 (DW_TAG_subrange_type)
+ i64, ;; Low value
+ i64 ;; High value
+ )
}
These descriptors are used to define ranges of array subscripts for an array
.. code-block:: llvm
!6 = metadata !{
- i32, ;; Tag = 40 (DW_TAG_enumerator)
- metadata, ;; Name
- i64 ;; Value
+ DIHeader(
+ i32, ;; Tag = 40 (DW_TAG_enumerator)
+ mdstring, ;; Name
+ i64 ;; Value
+ )
}
These descriptors are used to define members of an enumeration :ref:`composite
.. code-block:: llvm
!7 = metadata !{
- i32, ;; Tag (see below)
+ DIHeader(
+ i32, ;; Tag (see below)
+ mdstring, ;; Name
+ i32, ;; 24 bit - Line number where defined
+ ;; 8 bit - Argument number. 1 indicates 1st argument.
+ i32 ;; flags
+ ),
metadata, ;; Context
- metadata, ;; Name
metadata, ;; Reference to file where defined
- i32, ;; 24 bit - Line number where defined
- ;; 8 bit - Argument number. 1 indicates 1st argument.
metadata, ;; Reference to the type descriptor
- i32, ;; flags
metadata ;; (optional) Reference to inline location
- metadata ;; (optional) Reference to a complex expression.
}
These descriptors are used to define variables local to a sub program. The
projects / oota-llvm.git / blobdiff