through 'abstract'. In 4.1 Latex.
Not quite half of the first page of index entries
done once these committed.
Working through the abstract instance examples it was
natural to do some of the
concrete instance example indexing too.
Explained in READMEindexing how to get < and > characters to print.
\addtoindexi{address selection}{address selection|see{base address selection}}
+Use \textgreater and \textless to represent < and >
+in indexes (and other contexts). For example
+ \textless caf\textgreater results in <caf>
+oddly enough.
---Linking
\subsection{Inlining and out-of-line-instances}
\label{app:inliningandoutoflineinstances}
-Abstract instances and concrete-out-of-line instances may be
+Abstract instances
+\addtoindexx{abstract instance}
+\addtoindexx{concrete out-of-line instance}
+and concrete-out-of-line instances may be
put in distinct compilation units using section groups. This
makes possible some useful duplicate DWARF elimination.
\section{32-Bit and 64-Bit DWARF Formats}
\label{datarep:32bitand64bitdwarfformats}
+\addtoindexx{32-bit DWARF format}
+\addtoindexx{64-bit DWARF format}
There are two closely related file formats. In the 32\dash bit DWARF
format, all values that represent lengths of DWARF sections
and offsets relative to the beginning of DWARF sections are
its children.
Each debugging information entry begins with a code that
-represents an entry in a separate abbreviations table. This
+represents an entry in a separate
+\addtoindex{abbreviations table}. This
code is followed directly by a series of attribute values.
-The appropriate entry in the abbreviations table guides the
+The appropriate entry in the
+\addtoindex{abbreviations table} guides the
interpretation of the information contained directly in the
\addtoindex{.debug\_info} or
\addtoindex{.debug\_types} section.
\addtoindex{.debug\_types}
section begins with an unsigned
LEB128 number that represents its form. This allows producers
-to choose forms for particular attributes dynamically,
+to choose forms for particular attributes
+\addtoindexx{abbreviations table!dynamic forms in}
+dynamically,
without having to add a new entry to the abbreviations table.
The abbreviations for a given compilation unit end with an
Figure \refersec{fig:compilationunitsandabbreviationstable}
depicts the relationship of the abbreviations tables contained
+\addtoindexx{abbreviations table!example}
\addtoindexx{.debug\_abbrev example}
\addtoindexx{.debug\_info example}
in the \addtoindex{.debug\_abbrev}
\label{app:inliningexample1abstractinstance}
\begin{alltt}
! Abstract instance for OUTER
- !
+ ! \addtoindexx{abstract instance!example}
OUTER.AI.1.1:
\livelink{chap:DWTAGsubprogram}{DW\-\_TAG\-\_subprogram}
\livelink{chap:DWATname}{DW\-\_AT\-\_name}("OUTER")
\label{app:inliningexample1concreteinstance}
\begin{alltt}
! Concrete instance for call "OUTER(7)"
-!
+! \addtoindexx{concrete instance!example}
OUTER.CI.1.1:
\livelink{chap:DWTAGinlinedsubroutine}{DW\-\_TAG\-\_inlined\-\_subroutine}
! No name
In the second alternative we assume that subprogram INNER
is not inlinable for some reason, but subprogram OUTER is
-inlinable. Each concrete inlined instance of OUTER has its
-own normal instance of INNER. The abstract instance for OUTER,
+inlinable.
+\addtoindexx{concrete instance!example}
+Each concrete inlined instance of OUTER has its
+own normal instance of INNER.
+The abstract instance for OUTER,
+\addtoindexx{abstract instance!example}
which includes INNER, is shown in
Section \refersec{app:inliningexample2abstractinstance}.
Note that the debugging information in this Figure differs from
that in
Section \refersec{app:inliningexample1abstractinstance}
-in that INNER lacks a \livelink{chap:DWATinline}{DW\-\_AT\-\_inline} attribute
+in that INNER lacks a
+\livelink{chap:DWATinline}{DW\-\_AT\-\_inline} attribute
and therefore is not a distinct abstract instance. INNER
is merely an out\dash of\dash line routine that is part of OUTER’s
abstract instance. This is reflected in the Figure 70 by
+\addtoindexx{abstract instance!example}
the fact that the labels for INNER use the substring OUTER
instead of INNER.
-A resulting concrete inlined instance of OUTER is shown in
+A resulting
+\addtoindexx{concrete instance!example}
+concrete inlined instance of OUTER is shown in
Section \refersec{app:inliningexample2concreteinstance}.
Notice in
Section \refersec{app:inliningexample2concreteinstance}.
that OUTER is expanded as a concrete
+\addtoindexx{concrete instance!example}
inlined instance, and that INNER is nested within it as a
concrete out\dash of\dash line subprogram. Because INNER is cloned
for each inline expansion of OUTER, only the invariant
attributes of INNER
(for example, \livelink{chap:DWATname}{DW\-\_AT\-\_name}) are specified
in the abstract instance of OUTER, and the low\dash level,
+\addtoindexx{abstract instance!example}
instance\dash specific attributes of INNER (for example,
-\livelink{chap:DWATlowpc}{DW\-\_AT\-\_low\-\_pc}) are specified in each concrete instance of OUTER.
+\livelink{chap:DWATlowpc}{DW\-\_AT\-\_low\-\_pc}) are specified in
+each concrete instance of OUTER.
+\addtoindexx{concrete instance!example}
The several calls of INNER within OUTER are compiled as normal
calls to the instance of INNER that is specific to the same
instance of OUTER that contains the calls.
\label{app:inliningexample2abstractinstance}
\begin{alltt}
! Abstract instance for OUTER
- !
+ ! \addtoindex{abstract instance}
OUTER.AI.2.1:
\livelink{chap:DWTAGsubprogram}{DW\-\_TAG\-\_subprogram}
\livelink{chap:DWATname}{DW\-\_AT\-\_name}("OUTER")
In the third approach, one normal subprogram for INNER is
compiled which is called from all concrete inlined instances of
+\addtoindexx{concrete instance!example}
+\addtoindexx{abstract instance!example}
OUTER. The abstract instance for OUTER is shown in
Section \refersec{app:inliningexample3abstractinstance}.
The most distinctive aspect of that Figure is that subprogram
INNER exists only within the abstract instance of OUTER,
and not in OUTER’s concrete instance. In the abstract
+\addtoindexx{concrete instance!example}
+\addtoindexx{abstract instance!example}
instance of OUTER, the description of INNER has the full
complement of attributes that would be expected for a
normal subprogram. While attributes such as \livelink{chap:DWATlowpc}{DW\-\_AT\-\_low\-\_pc},
instances of OUTER and the abstract instance of OUTER includes
the complete description of INNER, so that the description of
INNER may be (and for reasons of space efficiency, should be)
-omitted from each concrete instance of OUTER.
+omitted from each
+\addtoindexx{concrete instance!example}
+concrete instance of OUTER.
There is one aspect of this approach that is problematical from
the DWARF perspective. The single compiled instance of INNER
is assumed to access up\dash level variables of OUTER; however,
those variables may well occur at varying positions within
-the frames that contain the concrete inlined instances. A
+the frames that contain the
+\addtoindexx{concrete instance!example}
+concrete inlined instances. A
compiler might implement this in several ways, including the
use of additional compiler generated parameters that provide
reference parameters for the up\dash level variables, or a compiler
\label{app:inliningexample3abstractinstance}
\begin{alltt}
! Abstract instance for OUTER
- !
+ ! \addtoindexx{abstract instance!example}
OUTER.AI.3.1:
\livelink{chap:DWTAGsubprogram}{DW\-\_TAG\-\_subprogram}
\livelink{chap:DWATname}{DW\-\_AT\-\_name}("OUTER")
\label{app:inliningexample3concreteinstance}
\begin{alltt}
! Concrete instance for call "OUTER(7)"
- !
+ ! \addtoindexx{concrete instance!example}
OUTER.CI.3.1:
\livelink{chap:DWTAGinlinedsubroutine}{DW\-\_TAG\-\_inlined\-\_subroutine}
! No name
\livelink{chap:DWATname}{DW\-\_AT\-\_name}("x")
\livelink{chap:DWATtype}{DW\-\_AT\-\_type}(reference to "int")
! Concrete instance for square(9)
- !
+ ! \addtoindexx{concrete instance!example}
20\$: \livelink{chap:DWTAGinlinedsubroutine}{DW\-\_TAG\-\_inlined\-\_subroutine}
\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin}(reference to 10\$)
\livelink{chap:DWATconstexpr}{DW\-\_AT\-\_const\-\_expr}(present)
&\livelink{chap:DWATimportnamespaceusingdeclaration}{Namespace using declaration} \\
&\livelink{chap:DWATimportnamespaceusingdirective}{Namespace using directive} \\
\livetarg{chap:DWATinline}{DW\-\_AT\-\_inline}
-&\livelink{chap:DWATinlineabstracttinstance}{Abstract instance} \\
+&\livelinki{chap:DWATinlineabstracttinstance}{Abstract instance}{abstract instance} \\
&\livelink{chap:DWATinlineinlinedsubroutine}{Inlined subroutine} \\
\livetarg{chap:DWATisoptional}{DW\-\_AT\-\_is\-\_optional}
&\livelink{chap:DWATisoptionaloptionalparameter}{Optional parameter} \\
The size of a segment selector in this CIE and any FDEs that
use it, in bytes.
-\item code\_alignment\_factor (unsigned LEB128) \\
-A constant that is factored out of all advance location
+\item \addtoindex{code\_alignment\_factor} (unsigned LEB128) \\
+\addtoindex{code alignment factor}
+A
+\addtoindexx{\textless caf\textgreater|see{code alignment factor}}
+constant that is factored out of all advance location
instructions (see
Section \refersec{chap:rowcreationinstructions}).
-\item data\_alignment\_factor (signed LEB128) \\
-A constant that is factored out of certain offset instructions
+\item \addtoindex{data\_alignment\_factor} (signed LEB128) \\
+\addtoindexx{data alignment factor}
+A
+\addtoindexx{\textless daf\textgreater|see{data alignment factor}}
+constant that is factored out of certain offset instructions
(see below). The resulting value is \textit{(operand *
data\_alignment\_factor)}.
action is to create a new table row with a location value that
is computed by taking the current entry’s location value
and adding the value of
-\textit{delta * code\_alignment\_factor}. All
+\textit{delta * \addtoindex{code\_alignment\_factor}}.
+All
other values in the new row are initially identical to the
current row
signed LEB128 factored offset. This instruction is identical
to \livelink{chap:DWCFAdefcfa}{DW\-\_CFA\-\_def\-\_cfa} except that the second operand is signed
and factored. The resulting offset is factored\_offset *
-data\_alignment\_factor.
+\addtoindex{data\_alignment\_factor}.
\item \textbf{DW\-\_CFA\-\_def\-\_cfa\-\_register} \\
LEB128 operand representing a factored offset. This instruction
is identical to \livelink{chap:DWCFAdefcfaoffset}{DW\-\_CFA\-\_def\-\_cfa\-\_offset} except that the
operand is signed and factored. The resulting offset is
-factored\_offset * data\_alignment\_factor. This operation
+factored\_offset * \addtoindex{data\_alignment\_factor}.
+This operation
is valid only if the current CFA rule is defined to use a
register and offset.
is to change the rule for the register indicated by the
register number to be an offset(N) rule where the value of
N is
-\textit{factored offset * data\_alignment\_factor.}
+\textit{factored offset * \addtoindex{data\_alignment\_factor}}.
\item \textbf{DW\-\_CFA\-\_offset\-\_extended} \\
The \livetarg{chap:DWCFAoffsetextended}{DW\-\_CFA\-\_offset\-\_extended} instruction takes two unsigned
signed LEB128 factored offset. This instruction is identical
to \livelink{chap:DWCFAoffsetextended}{DW\-\_CFA\-\_offset\-\_extended} except that the second operand is
signed and factored. The resulting offset is
-\textit{factored\_offset * data\_alignment\_factor}.
+\textit{factored\_offset * \addtoindex{data\_alignment\_factor}}.
\item \textbf{DW\-\_CFA\-\_val\-\_offset} \\
The \livetarg{chap:DWCFAvaloffset}{DW\-\_CFA\-\_val\-\_offset} instruction takes two unsigned
factored offset. The required action is to change the rule
for the register indicated by the register number to be a
val\_offset(N) rule where the value of N is
-\textit{factored\_offset * data\_alignment\_factor}.
+\textit{factored\_offset * \addtoindex{data\_alignment\_factor}}.
\item \textbf{DW\-\_CFA\-\_val\-\_offset\-\_sf} \\
The \livetarg{chap:DWCFAvaloffsetsf}{DW\-\_CFA\-\_val\-\_offset\-\_sf} instruction takes two operands: an
signed LEB128 factored offset. This instruction is identical
to \livelink{chap:DWCFAvaloffset}{DW\-\_CFA\-\_val\-\_offset} except that the second operand is signed
and factored. The resulting offset is
-\textit{factored\_offset * data\_alignment\_factor}.
+\textit{factored\_offset * \addtoindex{data\_alignment\_factor}}.
\item \textbf{DW\-\_CFA\-\_register} \\
The \livetarg{chap:DWCFAregister}{DW\-\_CFA\-\_register} instruction takes two unsigned LEB128
directly or indirectly) by a debugging information entry
that contains the
\livelink{chap:DWATinline}{DW\-\_AT\-\_inline} attribute is referred to
-as an ``abstract instance entry.'' Any subroutine entry
+\addtoindexx{abstract instance!entry}
+as an ``abstract instance entry.''
+Any subroutine entry
that contains a \livelink{chap:DWATinline}{DW\-\_AT\-\_inline} attribute whose value is other
-than \livelink{chap:DWINLnotinlined}{DW\-\_INL\-\_not\-\_inlined} is known as
+than \livelink{chap:DWINLnotinlined}{DW\-\_INL\-\_not\-\_inlined}
+is known as
+\addtoindexx{abstract instance!root}
an ``abstract instance root.''
Any set of abstract instance entries that are all
children (either directly or indirectly) of some abstract
instance root, together with the root itself, is known as
+\addtoindexx{abstract instance!tree}
an ``abstract instance tree.'' However, in the case where
an abstract instance tree is nested within another abstract
instance tree, the entries in the nested abstract instance
instance tree.
Each abstract instance root is either part of a larger
+\addtoindexx{abstract instance!root}
tree (which gives a context for the root) or uses
\livelink{chap:DWATspecification}{DW\-\_AT\-\_specification} to refer to the declaration in context.
abstract instance). In place of these omitted attributes, each
\hypertarget{chap:DWATabstractorigininlineinstance}
concrete inlined instance entry
+\addtoindexx{abstract origin attribute}
has a
\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin}
attribute that may be used to obtain the missing information
origin attribute.
For each pair of entries that are associated via a
+\addtoindexx{abstract origin attribute}
\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin} attribute, both members of the pair
have the same tag. So, for example, an entry with the tag
\livelink{chap:DWTAGvariable}{DW\-\_TAG\-\_variable} can only be associated with another entry
\begin{enumerate}[1.]
\item An entry in the concrete instance tree may be omitted if
-it contains only a \livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin} attribute and either
+it contains only a
+\addtoindexx{abstract origin attribute}
+\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin} attribute and either
has no children, or its children are omitted. Such entries
would provide no useful information. In C\dash like languages,
such entries frequently include types, including structure,
to describe new entities that are specific to a particular
inlined expansion. In that case, they will not have associated
entries in the abstract instance tree, should not contain
+\addtoindexx{abstract origin attribute}
\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin} attributes, and must contain all their
own attributes directly. This allows an abstract instance tree
to omit debugging information entries for anonymous entities
the preceding section). The representation of such a concrete
% It is critical that the hypertarget and livelink be
% separated to avoid problems with latex.
-out\dash of\dash line instance
+out\dash of\dash line
+\addtoindexx{abstract origin attribute}
+instance
\hypertarget{chap:DWATabstractoriginoutoflineinstance}
makes use of
\livelink{chap:DWATabstractorigin}{DW\-\_AT\-\_abstract\-\_origin}
For an inlined subroutine nested within another inlined
subroutine, the following rules apply to their abstract and
+\addtoindexx{abstract instance!nested}
+\addtoindexx{concrete instance!nested}
concrete instance trees:
\begin{enumerate}[1.]
DWARF Git Projects / dwarf-doc.git / commitdiff