Merge exception handling

Author: rossberg

README.md

@@ -3,18 +3,11 @@
 
 # spec
 
-This repository holds a prototypical reference implementation for WebAssembly,
-which is currently serving as the official specification. Eventually, we expect
-to produce a specification either written in human-readable prose or in a formal
-specification language.
+This repository holds the sources for the WebAssembly specification,
+a reference implementation, and the official test suite.
 
-It also holds the WebAssembly testsuite, which tests numerous aspects of
-conformance to the spec.
-
-View the work-in-progress spec at [webassembly.github.io/spec](https://webassembly.github.io/spec/).
-
-At this time, the contents of this repository are under development and known
-to be "incomplet and inkorrect".
+A formatted version of the spec is available here:
+[webassembly.github.io/spec](https://webassembly.github.io/spec/),
 
 Participation is welcome. Discussions about new features, significant semantic
 changes, or any specification change likely to generate substantial discussion

deploy_key

@@ -12,7 +12,7 @@ Release 2.0
 
 .. index:: instruction, integer
 
-Sign extension instructions
+Sign Extension Instructions
 ...........................
 
 Added new numeric instructions for performing sign extension within integer representations. [#proposal-signext]_
@@ -22,7 +22,7 @@ Added new numeric instructions for performing sign extension within integer repr
 
 .. index:: instruction, trap, floating-point, integer
 
-Non-trapping float-to-int conversions
+Non-trapping Float-to-Int Conversions
 .....................................
 
 Added new conversion instructions that avoid trapping when converting a floating-point number to an integer. [#proposal-cvtsat]_
@@ -32,7 +32,7 @@ Added new conversion instructions that avoid trapping when converting a floating
 
 .. index:: block, function, value type, result type
 
-Multiple values
+Multiple Values
 ...............
 
 Generalized the result type of blocks and functions to allow for multiple values; in addition, introduced the ability to have block parameters. [#proposal-multivalue]_
@@ -44,7 +44,7 @@ Generalized the result type of blocks and functions to allow for multiple values
 
 .. index:: value type, reference, reference type, instruction, element segment
 
-Reference types
+Reference Types
 ...............
 
 Added |FUNCREF| and |EXTERNREF| as new value types and respective instructions. [#proposal-reftype]_
@@ -60,7 +60,7 @@ Added |FUNCREF| and |EXTERNREF| as new value types and respective instructions.
 
 .. index:: reference, instruction, table, table type
 
-Table instructions
+Table Instructions
 ..................
 
 Added instructions to directly access and modify tables. [#proposal-reftype]_
@@ -72,7 +72,7 @@ Added instructions to directly access and modify tables. [#proposal-reftype]_
 
 .. index:: table, instruction, table index, element segment, import, export
 
-Multiple tables
+Multiple Tables
 ...............
 
 Added the ability to use multiple tables per module. [#proposal-reftype]_
@@ -86,7 +86,7 @@ Added the ability to use multiple tables per module. [#proposal-reftype]_
 
 .. index:: instruction, table, memory, data segment, element segment
 
-Bulk memory and table instructions
+Bulk Memory and Table Instructions
 ..................................
 
 Added instructions that modify ranges of memory or table entries. [#proposal-reftype]_ [#proposal-bulk]_
@@ -106,7 +106,7 @@ Added instructions that modify ranges of memory or table entries. [#proposal-ref
 
 .. index:: instructions, SIMD, value type, vector type
 
-Vector instructions
+Vector Instructions
 ...................
 
 Added vector type and instructions that manipulate multiple numeric values in parallel (also known as *SIMD*, single instruction multiple data) [#proposal-vectype]_
@@ -160,90 +160,89 @@ Added vector type and instructions that manipulate multiple numeric values in pa
 Release 3.0
 ~~~~~~~~~~~
 
-.. index: instruction, function, call
+.. index: instruction, expression, constant
 
-Tail Calls
-..........
+Extended Constant Expressions
+.............................
 
-Added instructions to perform tail calls [#proposal-tailcall]_.
+Allowed basic numeric computations in constant expressions. [#proposal-extconst]_
 
-* New :ref:`control instructions <syntax-instr-control>`: :math:`RETURNCALL` and :math:`RETURNCALLINDIRECT`
+* Extended set of :ref:`constant instructions <valid-const>` with :math:`\K{i}\X{nn}\K{.add}`, :math:`\K{i}\X{nn}\K{.sub}`, and :math:`\K{i}\X{nn}\K{.mul}`, and |GLOBALGET| for any previously declared immutable :ref:`global <syntax-global>`
 
+.. note::
+   The :ref:`garbage collection <extension-gc>` added further constant instructions.
 
-.. index:: reference, reference type, heap type, value type, local, local type, instruction, instruction type, table, function, function type, matching, subtyping
 
-Typeful References
-..................
-
-Added more precise types for references [#proposal-typedref]_.
+.. index: instruction, function, call
 
-* New generalised form of :ref:`reference types <syntax-reftype>`: :math:`(\REF~\NULL^?~\heaptype)`
+Tail Calls
+..........
 
-* New class of :ref:`heap types <syntax-heaptype>`: |FUNC|, |EXTERN|, :math:`\typeidx`
+Added instructions to perform tail calls. [#proposal-tailcall]_
 
-* Basic :ref:`subtyping <match>` on :ref:`reference <match-reftype>` and :ref:`value <match-valtype>` types
+* New :ref:`control instructions <syntax-instr-control>`: |RETURNCALL| and |RETURNCALLINDIRECT|
 
-* New :ref:`reference instructions <syntax-instr-ref>`: |REFASNONNULL|, |BRONNULL|, |BRONNONNULL|
 
-* New :ref:`control instruction <syntax-instr-control>`: |CALLREF|
+.. index:: instruction, exception, reference type, tag type, tag, handler
 
-* Refined typing of :ref:`reference instruction <syntax-instr-ref>` |REFFUNC| with more precise result type
+Exception Handling
+..................
 
-* Refined typing of :ref:`local instructions <valid-instr-variable>` and :ref:`instruction sequences <valid-instr-seq>` to track the :ref:`initialization status <syntax-init>` of :ref:`locals <syntax-local>` with non-:ref:`defaultable <valid-defaultable>` type
+Added tag definitions, imports, and exports, and instructions to throw and catch exceptions [#proposal-exn]_
 
-* Extended :ref:`table definitions <syntax-table>` with optional initializer expression
+* Modules may :ref:`define <syntax-tagtype>`, :ref:`import <syntax-import>`, and :ref:`export <syntax-export>` tags.
 
+* New :ref:`heap types <syntax-heaptype>`: |EXN|, |NOEXN|
 
-.. index:: reference, reference type, heap type, field type, storage type, structure type, array type, composite type, sub type, recursive type
+* New :ref:`reference type <syntax-reftype>` short-hands: |EXNREF|, |NULLEXNREF|
 
-Garbage Collection
-..................
+* New :ref:`control instructions <syntax-instr-control>`: |THROW|, |THROWREF|, and |TRYTABLE|.
 
-Added managed reference types [#proposal-gc]_.
+* New :ref:`tag section <binary-tagsec>` in binary format.
 
-* New forms of :ref:`heap types <syntax-heaptype>`: |ANY|, |EQT|, |I31|, |STRUCT|, |ARRAY|, |NONE|, |NOFUNC|, |NOEXTERN|
 
-* New :ref:`reference type <syntax-reftype>` short-hands: |ANYREF|, |EQREF|, |I31REF|, |STRUCTREF|, |ARRAYREF|, |NULLREF|, |NULLFUNCREF|, |NULLEXTERNREF|
+.. index: instruction, memory, memory index, data segment, import, export
 
-* New forms of type definitions: :ref:`structure <syntax-structtype>` and :ref:`array types <syntax-arraytype>`, :ref:`sub types <syntax-subtype>`, and :ref:`recursive types <syntax-rectype>`
+Multiple Memories
+.................
 
-* Enriched :ref:`subtyping <match>` based on explicitly declared :ref:`sub types <syntax-subtype>` and the new heap types
+Added the ability to use multiple memories per module. [#proposal-multimem]_
 
-* New generic :ref:`reference instructions <syntax-instr-ref>`: |REFEQ|, |REFTEST|, |REFCAST|, |BRONCAST|, |BRONCASTFAIL|
+* :ref:`Modules <syntax-module>` may :ref:`define <syntax-mem>`, :ref:`import <syntax-import>`, and :ref:`export <syntax-export>` multiple memories
 
-* New :ref:`reference instructions <syntax-instr-ref>` for :ref:`unboxed scalars <syntax-i31>`: |REFI31|, :math:`\I31GET\K{\_}\sx`
+* :ref:`Memory instructions <syntax-instr-memory>` take a :ref:`memory index <syntax-memidx>` immediate: |MEMORYSIZE|, |MEMORYGROW|, |MEMORYFILL|, |MEMORYCOPY|, |MEMORYINIT|, :math:`t\K{.load}`, :math:`t\K{.store}`, :math:`t\K{.load}\!N\!\K{\_}\sx`, :math:`t\K{.store}\!N`, :math:`\K{v128.load}\!N\!\K{x}\!M\!\K{\_}\sx`, :math:`\K{v128.load}\!N\!\K{\_zero}`, :math:`\K{v128.load}\!N\!\K{\_splat}`, :math:`\K{v128.load}\!N\!\K{\_lane}`, :math:`\K{v128.store}\!N\!\K{\_lane}`
 
-* New :ref:`reference instructions <syntax-instr-ref>` for :ref:`structure types <syntax-structtype>`: |STRUCTNEW|, |STRUCTNEWDEFAULT|, :math:`\STRUCTGET\K{\_}\sx^?`, |STRUCTSET|
+* :ref:`Data segments <syntax-elem>` take a :ref:`memory index <syntax-memidx>`
 
-* New :ref:`reference instructions <syntax-instr-ref>` for :ref:`array types <syntax-structtype>`: |ARRAYNEW|, |ARRAYNEWDEFAULT|, |ARRAYNEWFIXED|, |ARRAYNEWDATA|, |ARRAYNEWELEM|, :math:`\ARRAYGET\K{\_}\sx^?`, |ARRAYSET|, |ARRAYLEN|, |ARRAYFILL|, |ARRAYCOPY|, |ARRAYINITDATA|, |ARRAYINITELEM|
 
-* New :ref:`reference instructions <syntax-instr-ref>` for converting :ref:`host types <syntax-externtype>`: |ANYCONVERTEXTERN|, |EXTERNCONVERTANY|
+.. index:: reference, reference type, heap type, value type, local, local type, instruction, instruction type, table, function, function type, matching, subtyping
 
-* Extended set of :ref:`constant instructions <valid-const>` with |REFI31|, |STRUCTNEW|, |STRUCTNEWDEFAULT|, |ARRAYNEW|, |ARRAYNEWDEFAULT|, |ARRAYNEWFIXED|, |ANYCONVERTEXTERN|, |EXTERNCONVERTANY|, and |GLOBALGET| for any previously declared immutable :ref:`global <syntax-global>`
+Typeful References
+..................
 
+Added more precise types for references. [#proposal-typedref]_
 
-.. index:: instruction, exception, reference type, tag type, tag, handler
+* New generalised form of :ref:`reference types <syntax-reftype>`: :math:`(\REF~\NULL^?~\heaptype)`
 
-Exception Handling
-..................
+* New class of :ref:`heap types <syntax-heaptype>`: |FUNC|, |EXTERN|, :math:`\typeidx`
 
-Added tag definitions, imports, and exports, and instructions to throw and catch exceptions [#proposal-exn]_
+* Basic :ref:`subtyping <match>` on :ref:`reference <match-reftype>` and :ref:`value <match-valtype>` types
 
-* Modules may :ref:`define <syntax-tagtype>`, :ref:`import <syntax-import>`, and :ref:`export <syntax-export>` tags.
+* New :ref:`reference instructions <syntax-instr-ref>`: |REFASNONNULL|, |BRONNULL|, |BRONNONNULL|
 
-* New :ref:`heap types <syntax-heaptype>`: |EXN|, |NOEXN|
+* New :ref:`control instruction <syntax-instr-control>`: |CALLREF|
 
-* New :ref:`reference type <syntax-reftype>` short-hands: |EXNREF|, |NULLEXNREF|
+* Refined typing of :ref:`reference instruction <syntax-instr-ref>` |REFFUNC| with more precise result type
 
-* New :ref:`control instructions <syntax-instr-control>`: |THROW|, |THROWREF|, and |TRYTABLE|.
+* Refined typing of :ref:`local instructions <valid-instr-variable>` and :ref:`instruction sequences <valid-instr-seq>` to track the :ref:`initialization status <syntax-init>` of :ref:`locals <syntax-local>` with non-:ref:`defaultable <valid-defaultable>` type
 
-* New :ref:`tag section <binary-tagsec>` in binary format.
+* Extended :ref:`table definitions <syntax-table>` with optional initializer expression
 
 
 .. index:: reference, reference type, heap type, field type, storage type, structure type, array type, composite type, sub type, recursive type
 .. _extension-gc:
 
-Garbage collection
+Garbage Collection
 ..................
 
 Added managed reference types. [#proposal-gc]_
@@ -271,7 +270,7 @@ Added managed reference types. [#proposal-gc]_
 
 .. index: text format, annotation, custom section, identifier, module, type, function, local, structure field
 
-Custom annotations
+Custom Annotations
 ..................
 
 Added generic syntax for custom annotations in the text format,
@@ -292,15 +291,15 @@ mirroring the role of custom sections in the binary format. [#proposal-annot]_
 .. [#proposal-tailcall]
    https://github.com/WebAssembly/spec/tree/main/proposals/tail-call/
 
+.. [#proposal-exn]
+   https://github.com/WebAssembly/spec/tree/main/proposals/exception-handling/
+
 .. [#proposal-multimem]
    https://github.com/WebAssembly/multi-memory/blob/main/proposals/multi-memory/
 
 .. [#proposal-typedref]
    https://github.com/WebAssembly/spec/tree/main/proposals/function-references/
 
-.. [#proposal-exn]
-   https://github.com/WebAssembly/spec/tree/main/proposals/exception-handling/
-
 .. [#proposal-gc]
    https://github.com/WebAssembly/spec/tree/main/proposals/gc/