[spec] Runtime format of element and data segments (#91)

This is copied and modified from this closed PR:

WebAssembly/bulk-memory-operations#19

document/core/exec/modules.rst

@@ -371,6 +371,58 @@ New instances of :ref:`functions <syntax-funcinst>`, :ref:`tables <syntax-tablei
    \end{array}
 
 
+.. index:: element, element instance, element address
+.. _alloc-elem:
+
+:ref:`Element segments <syntax-eleminst>`
+.........................................
+
+1. Let :math:`\funcelem^\ast` be the vector of :ref:`function elements <syntax-funcelem>` to allocate.
+
+2. Let :math:`a` be the first free :ref:`element address <syntax-elemaddr>` in :math:`S`.
+
+3. Let :math:`\eleminst` be the :ref:`element instance <syntax-eleminst>` :math:`\{ \EIINIT~\funcelem^\ast \}`.
+
+4. Append :math:`\eleminst` to the |SELEM| of :math:`S`.
+
+5. Return :math:`a`.
+
+.. math::
+  \begin{array}{rlll}
+  \allocelem(S, \funcelem^\ast) &=& S', \elemaddr \\[1ex]
+  \mbox{where:} \hfill \\
+  \elemaddr &=& |S.\SELEM| \\
+  \eleminst &=& \{ \EIINIT~\funcelem^\ast \} \\
+  S' &=& S \compose \{\SELEM~\eleminst\} \\
+  \end{array}
+
+
+.. index:: data, data instance, data address
+.. _alloc-data:
+
+:ref:`Data segments <syntax-datainst>`
+......................................
+
+1. Let :math:`\bytes` be the vector of :ref:`bytes <syntax-byte>` to allocate.
+
+2. Let :math:`a` be the first free :ref:`data address <syntax-dataaddr>` in :math:`S`.
+
+3. Let :math:`\datainst` be the :ref:`data instance <syntax-datainst>` :math:`\{ \DIINIT~\bytes \}`.
+
+4. Append :math:`\datainst` to the |SDATA| of :math:`S`.
+
+5. Return :math:`a`.
+
+.. math::
+  \begin{array}{rlll}
+  \allocdata(S, \bytes) &=& S', \dataaddr \\[1ex]
+  \mbox{where:} \hfill \\
+  \dataaddr &=& |S.\SDATA| \\
+  \datainst &=& \{ \DIINIT~\bytes \} \\
+  S' &=& S \compose \{\SDATA~\datainst\} \\
+  \end{array}
+
+
 .. index:: table, table instance, table address, grow, limits
 .. _grow-table:
 

document/core/exec/runtime.rst

@@ -60,7 +60,7 @@ Store
 ~~~~~
 
 The *store* represents all global state that can be manipulated by WebAssembly programs.
-It consists of the runtime representation of all *instances* of :ref:`functions <syntax-funcinst>`, :ref:`tables <syntax-tableinst>`, :ref:`memories <syntax-meminst>`, and :ref:`globals <syntax-globalinst>` that have been :ref:`allocated <alloc>` during the life time of the abstract machine. [#gc]_
+It consists of the runtime representation of all *instances* of :ref:`functions <syntax-funcinst>`, :ref:`tables <syntax-tableinst>`, :ref:`memories <syntax-meminst>`, and :ref:`globals <syntax-globalinst>`, :ref:`element segments <syntax-eleminst>`, and :ref:`data segments <syntax-datainst>` that have been :ref:`allocated <alloc>` during the life time of the abstract machine. [#gc]_
 
 Syntactically, the store is defined as a :ref:`record <notation-record>` listing the existing instances of each category:
 
@@ -71,7 +71,9 @@ Syntactically, the store is defined as a :ref:`record <notation-record>` listing
      \SFUNCS & \funcinst^\ast, \\
      \STABLES & \tableinst^\ast, \\
      \SMEMS & \meminst^\ast, \\
-     \SGLOBALS & \globalinst^\ast ~\} \\
+     \SGLOBALS & \globalinst^\ast, \\
+     \SELEM & (\eleminst^?)^\ast, \\
+     \SDATA & (\datainst^?)^\ast ~\} \\
      \end{array}
    \end{array}
 
@@ -87,25 +89,31 @@ Convention
 * The meta variable :math:`S` ranges over stores where clear from context.
 
 
-.. index:: ! address, store, function instance, table instance, memory instance, global instance, embedder
+.. index:: ! address, store, function instance, table instance, memory instance, global instance, element instance, data instance, embedder
    pair: abstract syntax; function address
    pair: abstract syntax; table address
    pair: abstract syntax; memory address
    pair: abstract syntax; global address
+   pair: abstract syntax; element address
+   pair: abstract syntax; data address
    pair: function; address
    pair: table; address
    pair: memory; address
    pair: global; address
+   pair: element; address
+   pair: data; address
 .. _syntax-funcaddr:
 .. _syntax-tableaddr:
 .. _syntax-memaddr:
 .. _syntax-globaladdr:
+.. _syntax-elemaddr:
+.. _syntax-dataaddr:
 .. _syntax-addr:
 
 Addresses
 ~~~~~~~~~
 
-:ref:`Function instances <syntax-funcinst>`, :ref:`table instances <syntax-tableinst>`, :ref:`memory instances <syntax-meminst>`, and :ref:`global instances <syntax-globalinst>` in the :ref:`store <syntax-store>` are referenced with abstract *addresses*.
+:ref:`Function instances <syntax-funcinst>`, :ref:`table instances <syntax-tableinst>`, :ref:`memory instances <syntax-meminst>`, and :ref:`global instances <syntax-globalinst>`, :ref:`element instances <syntax-eleminst>`, and :ref:`data instances <syntax-datainst>` in the :ref:`store <syntax-store>` are referenced with abstract *addresses*.
 These are simply indices into the respective store component.
 
 .. math::
@@ -120,6 +128,10 @@ These are simply indices into the respective store component.
      \addr \\
    \production{(global address)} & \globaladdr &::=&
      \addr \\
+   \production{(element address)} & \elemaddr &::=&
+     \addr \\
+   \production{(data address)} & \dataaddr &::=&
+     \addr \\
    \end{array}
 
 An :ref:`embedder <embedder>` may assign identity to :ref:`exported <syntax-export>` store objects corresponding to their addresses,
@@ -137,7 +149,7 @@ even where this identity is not observable from within WebAssembly code itself
    hence logical addresses can be arbitrarily large natural numbers.
 
 
-.. index:: ! instance, function type, function instance, table instance, memory instance, global instance, export instance, table address, memory address, global address, index, name
+.. index:: ! instance, function type, function instance, table instance, memory instance, global instance, element instance, data instance, export instance, table address, memory address, global address, element address, data address, index, name
    pair: abstract syntax; module instance
    pair: module; instance
 .. _syntax-moduleinst:
@@ -158,6 +170,8 @@ and collects runtime representations of all entities that are imported, defined,
      \MITABLES & \tableaddr^\ast, \\
      \MIMEMS & \memaddr^\ast, \\
      \MIGLOBALS & \globaladdr^\ast, \\
+     \MIELEMS & (\elemaddr^?)^\ast, \\
+     \MIDATAS & (\dataaddr^?)^\ast, \\
      \MIEXPORTS & \exportinst^\ast ~\} \\
      \end{array}
    \end{array}
@@ -275,6 +289,42 @@ It holds an individual :ref:`value <syntax-val>` and a flag indicating whether i
 The value of mutable globals can be mutated through :ref:`variable instructions <syntax-instr-variable>` or by external means provided by the :ref:`embedder <embedder>`.
 
 
+.. index:: ! element instance, element segment, embedder, element expression
+   pair: abstract syntax; element instance
+   pair: element; instance
+.. _syntax-eleminst:
+
+Element Instances
+~~~~~~~~~~~~~~~~~
+
+An *element instance* is the runtime representation of an :ref:`element segment <syntax-elem>`.
+Like table instances, an element instance holds a vector of function elements.
+
+.. math::
+  \begin{array}{llll}
+  \production{(element instance)} & \eleminst &::=&
+    \{ \EIINIT~\vec(\funcelem) \} \\
+  \end{array}
+
+
+.. index:: ! data instance, data segment, embedder, byte
+  pair: abstract syntax; data instance
+  pair: data; instance
+.. _syntax-datainst:
+
+Data Instances
+~~~~~~~~~~~~~~
+
+An *data instance* is the runtime representation of a :ref:`data segment <syntax-data>`.
+It holds a vector of :ref:`bytes <syntax-byte>`.
+
+.. math::
+  \begin{array}{llll}
+  \production{(data instance)} & \datainst &::=&
+    \{ \DIINIT~\vec(\byte) \} \\
+  \end{array}
+
+
 .. index:: ! export instance, export, name, external value
    pair: abstract syntax; export instance
    pair: export; instance

document/core/util/macros.def

@@ -806,6 +806,8 @@
 .. |alloctable| mathdef:: \xref{exec/modules}{alloc-table}{\F{alloctable}}
 .. |allocmem| mathdef:: \xref{exec/modules}{alloc-mem}{\F{allocmem}}
 .. |allocglobal| mathdef:: \xref{exec/modules}{alloc-global}{\F{allocglobal}}
+.. |allocelem| mathdef:: \xref{exec/modules}{alloc-elem}{\F{allocelem}}
+.. |allocdata| mathdef:: \xref{exec/modules}{alloc-data}{\F{allocdata}}
 .. |allocmodule| mathdef:: \xref{exec/modules}{alloc-module}{\F{allocmodule}}
 
 .. |growtable| mathdef:: \xref{exec/modules}{grow-table}{\F{growtable}}
@@ -819,7 +821,8 @@
 .. |tableaddr| mathdef:: \xref{exec/runtime}{syntax-tableaddr}{\X{tableaddr}}
 .. |memaddr| mathdef:: \xref{exec/runtime}{syntax-memaddr}{\X{memaddr}}
 .. |globaladdr| mathdef:: \xref{exec/runtime}{syntax-globaladdr}{\X{globaladdr}}
-
+.. |elemaddr| mathdef:: \xref{exec/runtime}{syntax-elemaddr}{\X{elemaddr}}
+.. |dataaddr| mathdef:: \xref{exec/runtime}{syntax-dataaddr}{\X{dataaddr}}
 
 .. Instances, terminals
 
@@ -837,6 +840,10 @@
 .. |GIVALUE| mathdef:: \xref{exec/runtime}{syntax-globalinst}{\K{value}}
 .. |GIMUT| mathdef:: \xref{exec/runtime}{syntax-globalinst}{\K{mut}}
 
+.. |EIINIT| mathdef:: \xref{exec/runtime}{syntax-eleminst}{\K{init}}
+
+.. |DIINIT| mathdef:: \xref{exec/runtime}{syntax-datainst}{\K{init}}
+
 .. |EINAME| mathdef:: \xref{exec/runtime}{syntax-exportinst}{\K{name}}
 .. |EIVALUE| mathdef:: \xref{exec/runtime}{syntax-exportinst}{\K{value}}
 
@@ -850,6 +857,8 @@
 .. |MITABLES| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{tableaddrs}}
 .. |MIMEMS| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{memaddrs}}
 .. |MIGLOBALS| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{globaladdrs}}
+.. |MIELEMS| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{elemaddrs}}
+.. |MIDATAS| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{dataaddrs}}
 .. |MIEXPORTS| mathdef:: \xref{exec/runtime}{syntax-moduleinst}{\K{exports}}
 
 
@@ -863,6 +872,8 @@
 .. |funcelem| mathdef:: \xref{exec/runtime}{syntax-funcelem}{\X{funcelem}}
 .. |meminst| mathdef:: \xref{exec/runtime}{syntax-meminst}{\X{meminst}}
 .. |globalinst| mathdef:: \xref{exec/runtime}{syntax-globalinst}{\X{globalinst}}
+.. |eleminst| mathdef:: \xref{exec/runtime}{syntax-eleminst}{\X{eleminst}}
+.. |datainst| mathdef:: \xref{exec/runtime}{syntax-datainst}{\X{datainst}}
 .. |exportinst| mathdef:: \xref{exec/runtime}{syntax-exportinst}{\X{exportinst}}
 
 .. |hostfunc| mathdef:: \xref{exec/runtime}{syntax-hostfunc}{\X{hostfunc}}
@@ -882,7 +893,8 @@
 .. |STABLES| mathdef:: \xref{exec/runtime}{syntax-store}{\K{tables}}
 .. |SMEMS| mathdef:: \xref{exec/runtime}{syntax-store}{\K{mems}}
 .. |SGLOBALS| mathdef:: \xref{exec/runtime}{syntax-store}{\K{globals}}
-
+.. |SELEM| mathdef:: \xref{exec/runtime}{syntax-store}{\K{elem}}
+.. |SDATA| mathdef:: \xref{exec/runtime}{syntax-store}{\K{data}}
 
 .. Store, non-terminals