Merge pull request #422 from WebAssembly/ref.i31

rossberg · web-flow · commit 5d2313b3467f · 2023-09-12T08:24:49.000+02:00
Rename i31.new mnemonic to ref.i31
diff --git a/document/core/appendix/changes.rst b/document/core/appendix/changes.rst
@@ -182,15 +182,15 @@ Added managed reference types [#proposal-gc]_.
 
 * New generic :ref:`reference instructions <syntax-instr-ref>`: |REFEQ|, |REFTEST|, |REFCAST|, |BRONCAST|, |BRONCASTFAIL|
 
-* New :ref:`reference instructions <syntax-instr-ref>` for :ref:`unboxed scalars <syntax-i31>`: |I31NEW|, :math:`\I31GET\K{\_}\sx`
+* New :ref:`reference instructions <syntax-instr-ref>` for :ref:`unboxed scalars <syntax-i31>`: |REFI31|, :math:`\I31GET\K{\_}\sx`
 
 * New :ref:`reference instructions <syntax-instr-ref>` for :ref:`structure types <syntax-structtype>`: |STRUCTNEW|, |STRUCTNEWDEFAULT|, :math:`\STRUCTGET\K{\_}\sx^?`, |STRUCTSET|
 
 * 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>`: |EXTERNINTERNALIZE|, |EXTERNEXTERNALIZE|
 
-* Extended set of :ref:`constant instructions <valid-const>` with |I31NEW|, |STRUCTNEW|, |STRUCTNEWDEFAULT|, |ARRAYNEW|, |ARRAYNEWDEFAULT|, |ARRAYNEWFIXED|, |EXTERNINTERNALIZE|, |EXTERNEXTERNALIZE|, and |GLOBALGET| for any previously declared immutable :ref:`global <syntax-global>`
+* Extended set of :ref:`constant instructions <valid-const>` with |REFI31|, |STRUCTNEW|, |STRUCTNEWDEFAULT|, |ARRAYNEW|, |ARRAYNEWDEFAULT|, |ARRAYNEWFIXED|, |EXTERNINTERNALIZE|, |EXTERNEXTERNALIZE|, and |GLOBALGET| for any previously declared immutable :ref:`global <syntax-global>`
 
 
 .. [#proposal-signext]
diff --git a/document/core/appendix/index-instructions.py b/document/core/appendix/index-instructions.py
@@ -348,7 +348,7 @@ def Instruction(name, opcode, type=None, validation=None, execution=None, operat
     Instruction(r'\BRONCASTFAIL~t_1~t_2', r'\hex{FB}~\hex{19}', r'[t_1] \to [t_2]', r'valid-br_on_cast_fail', r'exec-br_on_cast_fail'),
     Instruction(r'\EXTERNINTERNALIZE', r'\hex{FB}~\hex{1A}', r'[\EXTERNREF] \to [\ANYREF]', r'valid-extern.internalize', r'exec-extern.internalize'),
     Instruction(r'\EXTERNEXTERNALIZE', r'\hex{FB}~\hex{1B}', r'[\ANYREF] \to [\EXTERNREF]', r'valid-extern.externalize', r'exec-extern.externalize'),
-    Instruction(r'\I31NEW', r'\hex{FB}~\hex{1C}', r'[\I32] \to [\I31REF]', r'valid-i31.new', r'exec-i31.new'),
+    Instruction(r'\REFI31', r'\hex{FB}~\hex{1C}', r'[\I32] \to [\I31REF]', r'valid-ref.i31', r'exec-ref.i31'),
     Instruction(r'\I31GETS', r'\hex{FB}~\hex{1D}', r'[\I31REF] \to [\I32]', r'valid-i31.get_sx', r'exec-i31.get_sx'),
     Instruction(r'\I31GETU', r'\hex{FB}~\hex{1E}', r'[\I31REF] \to [\I32]', r'valid-i31.get_sx', r'exec-i31.get_sx'),
     Instruction(None, r'\hex{FB}~\hex{1E} \dots'),
diff --git a/document/core/binary/instructions.rst b/document/core/binary/instructions.rst
@@ -126,7 +126,7 @@ Generic :ref:`reference instructions <syntax-instr-ref>` are represented by sing
 .. _binary-array.copy:
 .. _binary-array.init_data:
 .. _binary-array.init_elem:
-.. _binary-i31.new:
+.. _binary-ref.i31:
 .. _binary-i31.get_s:
 .. _binary-i31.get_u:
 .. _binary-ref.test:
@@ -168,7 +168,7 @@ Generic :ref:`reference instructions <syntax-instr-ref>` are represented by sing
      \hex{FB}~~23{:}\Bu32~~\X{ht}{:}\Bheaptype &\Rightarrow& \REFCAST~(\REF~\NULL~\X{ht}) \\ &&|&
      \hex{FB}~~26{:}\Bu32 &\Rightarrow& \EXTERNINTERNALIZE \\ &&|&
      \hex{FB}~~27{:}\Bu32 &\Rightarrow& \EXTERNEXTERNALIZE \\ &&|&
-     \hex{FB}~~28{:}\Bu32 &\Rightarrow& \I31NEW \\ &&|&
+     \hex{FB}~~28{:}\Bu32 &\Rightarrow& \REFI31 \\ &&|&
      \hex{FB}~~29{:}\Bu32 &\Rightarrow& \I31GETS \\ &&|&
      \hex{FB}~~30{:}\Bu32 &\Rightarrow& \I31GETU \\
    \end{array}
diff --git a/document/core/exec/instructions.rst b/document/core/exec/instructions.rst
@@ -375,22 +375,22 @@ Reference Instructions
 
 
 
-.. _exec-i31.new:
+.. _exec-ref.i31:
 
-:math:`\I31NEW`
+:math:`\REFI31`
 ...............
 
-1. Assert: due to :ref:`validation <valid-i31.new>`, a :ref:`value <syntax-val>` of :ref:`type <syntax-valtype>` |I32| is on the top of the stack.
+1. Assert: due to :ref:`validation <valid-ref.i31>`, a :ref:`value <syntax-val>` of :ref:`type <syntax-valtype>` |I32| is on the top of the stack.
 
 2. Pop the value :math:`\I32.\CONST~i` from the stack.
 
 3. Let :math:`j` be the result of computing :math:`\wrap_{32,31}(i)`.
 
-4. Push the reference value :math:`(\REFI31~j)` to the stack.
+4. Push the reference value :math:`(\REFI31NUM~j)` to the stack.
 
 .. math::
    \begin{array}{lcl@{\qquad}l}
-   (\I32.\CONST~i)~\I31NEW &\stepto& (\REFI31~\wrap_{32,31}(i))
+   (\I32.\CONST~i)~\REFI31 &\stepto& (\REFI31NUM~\wrap_{32,31}(i))
    \end{array}
 
 
@@ -409,16 +409,16 @@ Reference Instructions
 
 4. Assert: due to :ref:`validation <valid-i31.get_sx>`, a :math:`\reff` is a :ref:`scalar reference <syntax-ref.i31>`.
 
-5. Let :math:`\REFI31~i` be the reference value :math:`\reff`.
+5. Let :math:`\REFI31NUM~i` be the reference value :math:`\reff`.
 
 6. Let :math:`j` be the result of computing :math:`\extend^{\sx}_{31,32}(i)`.
 
 7. Push the value :math:`\I32.\CONST~j` to the stack.
 
 .. math::
    \begin{array}{lcl@{\qquad}l}
-   (\REFI31~i)~\I31NEW &\stepto& (\I32.\CONST~\extend^{\sx}_{31,32}(i)) \\
-   (\REFNULL~t)~\I31NEW &\stepto& \TRAP
+   (\REFI31NUM~i)~\I31GET\K{\_}\sx &\stepto& (\I32.\CONST~\extend^{\sx}_{31,32}(i)) \\
+   (\REFNULL~t)~\I31GET\K{\_}\sx &\stepto& \TRAP
    \end{array}
 
 
diff --git a/document/core/exec/runtime.rst b/document/core/exec/runtime.rst
@@ -12,7 +12,7 @@ Runtime Structure
 .. _syntax-num:
 .. _syntax-vecc:
 .. _syntax-ref:
-.. _syntax-ref.i31:
+.. _syntax-ref.i31num:
 .. _syntax-ref.struct:
 .. _syntax-ref.array:
 .. _syntax-ref.host:
@@ -48,7 +48,7 @@ Any of the aformentioned references can furthermore be wrapped up as an *externa
      \V128.\CONST~\i128 \\
    \production{reference} & \reff &::=&
      \REFNULL~t \\&&|&
-     \REFI31~\u31 \\&&|&
+     \REFI31NUM~\u31 \\&&|&
      \REFSTRUCTADDR~\structaddr \\&&|&
      \REFARRAYADDR~\arrayaddr \\&&|&
      \REFFUNCADDR~\funcaddr \\&&|&
@@ -634,7 +634,7 @@ In order to express the reduction of :ref:`traps <trap>`, :ref:`calls <syntax-ca
    \production{administrative instruction} & \instr &::=&
      \dots \\ &&|&
      \TRAP \\ &&|&
-     \REFI31~\u31 \\&&|&
+     \REFI31NUM~\u31 \\&&|&
      \REFSTRUCTADDR~\structaddr \\&&|&
      \REFARRAYADDR~\arrayaddr \\&&|&
      \REFFUNCADDR~\funcaddr \\&&|&
@@ -649,7 +649,7 @@ In order to express the reduction of :ref:`traps <trap>`, :ref:`calls <syntax-ca
 The |TRAP| instruction represents the occurrence of a trap.
 Traps are bubbled up through nested instruction sequences, ultimately reducing the entire program to a single |TRAP| instruction, signalling abrupt termination.
 
-The |REFI31| instruction represents :ref:`unboxed scalar <syntax-ref.i31>` reference values,
+The |REFI31NUM| instruction represents :ref:`unboxed scalar <syntax-ref.i31>` reference values,
 |REFSTRUCTADDR| and |REFARRAYADDR| represent :ref:`structure <syntax-ref.struct>` and :ref:`array <syntax-ref.array>` reference values, respectively,
 and |REFFUNCADDR| instruction represents :ref:`function reference <syntax-ref.func>` values.
 Similarly, |REFHOSTADDR| represents :ref:`host references <syntax-ref.host>`
diff --git a/document/core/exec/values.rst b/document/core/exec/values.rst
@@ -66,17 +66,17 @@ The following auxiliary typing rules specify this typing relation relative to a
    That ensures that it is compatible with any nullable type in that hierarchy.
 
 
-.. _valid-ref.i31:
+.. _valid-ref.i31num:
 
-:ref:`Scalar References <syntax-ref>` :math:`\REFI31~i`
-.......................................................
+:ref:`Scalar References <syntax-ref>` :math:`\REFI31NUM~i`
+..........................................................
 
 * The value is valid with :ref:`reference type <syntax-reftype>` :math:`(\REF~\I31)`.
 
 .. math::
    \frac{
    }{
-     S \vdashval \REFI31~i : \REF~\I31
+     S \vdashval \REFI31NUM~i : \REF~\I31
    }
 
 
diff --git a/document/core/syntax/instructions.rst b/document/core/syntax/instructions.rst
@@ -482,7 +482,7 @@ while the latter performs a downcast and :ref:`traps <trap>` if the operand's ty
 .. _syntax-array.copy:
 .. _syntax-array.init_data:
 .. _syntax-array.init_elem:
-.. _syntax-i31.new:
+.. _syntax-ref.i31:
 .. _syntax-i31.get_s:
 .. _syntax-i31.get_u:
 .. _syntax-extern.internalize:
@@ -519,7 +519,7 @@ Instructions in this group are concerned with creating and accessing :ref:`refer
      \ARRAYCOPY~\typeidx~\typeidx \\&&|&
      \ARRAYINITDATA~\typeidx~\dataidx \\&&|&
      \ARRAYINITELEM~\typeidx~\elemidx \\&&|&
-     \I31NEW \\&&|&
+     \REFI31 \\&&|&
      \I31GET\K{\_}\sx \\&&|&
      \EXTERNINTERNALIZE \\&&|&
      \EXTERNEXTERNALIZE \\
@@ -537,7 +537,7 @@ again allowing for different sign extension modes in the case of a :ref:`packed
 |ARRAYLEN| produces the length of an array.
 |ARRAYFILL| fills a specified slice of an array with a given value and |ARRAYCOPY|, |ARRAYINITDATA|, and |ARRAYINITELEM| copy elements to a specified slice of an array from a given array, data segment, or element segment, respectively.
 
-The instructions |I31NEW| and :math:`\I31GET\K{\_}\sx` convert between type |I31| and an unboxed :ref:`scalar <syntax-i31>`.
+The instructions |REFI31| and :math:`\I31GET\K{\_}\sx` convert between type |I31| and an unboxed :ref:`scalar <syntax-i31>`.
 
 The instructions |EXTERNINTERNALIZE| and |EXTERNEXTERNALIZE| allow lossless conversion between references represented as type :math:`(\REF~\NULL~\EXTERN)`| and as :math:`(\REF~\NULL~\ANY)`.
 
diff --git a/document/core/text/instructions.rst b/document/core/text/instructions.rst
@@ -199,7 +199,7 @@ Reference Instructions
 .. _text-array.copy:
 .. _text-array.init_data:
 .. _text-array.init_elem:
-.. _text-i31.new:
+.. _text-ref.i31:
 .. _text-i31.get_s:
 .. _text-i31.get_u:
 .. _text-ref.test:
@@ -237,7 +237,7 @@ Reference Instructions
      \text{array.copy}~~x{:}\Ttypeidx_I~~y{:}\Ttypeidx_I &\Rightarrow& \ARRAYCOPY~x~y \\ &&|&
      \text{array.init\_data}~~x{:}\Ttypeidx_I~~y{:}\Tdataidx_I &\Rightarrow& \ARRAYINITDATA~x~y \\ &&|&
      \text{array.init\_elem}~~x{:}\Ttypeidx_I~~y{:}\Telemidx_I &\Rightarrow& \ARRAYINITELEM~x~y \\ &&|&
-     \text{i31.new} &\Rightarrow& \I31NEW \\ &&|&
+     \text{ref.i31} &\Rightarrow& \REFI31 \\ &&|&
      \text{i31.get\_u} &\Rightarrow& \I31GETU \\ &&|&
      \text{i31.get\_s} &\Rightarrow& \I31GETS \\ &&|&
      \text{extern.internalize} &\Rightarrow& \EXTERNINTERNALIZE \\ &&|&
diff --git a/document/core/util/macros.def b/document/core/util/macros.def
@@ -504,7 +504,7 @@
 .. |ARRAYINITDATA| mathdef:: \xref{syntax/instructions}{syntax-instr-aray}{\K{array.init\_data}}
 .. |ARRAYINITELEM| mathdef:: \xref{syntax/instructions}{syntax-instr-aray}{\K{array.init\_elem}}
 
-.. |I31NEW| mathdef:: \xref{syntax/instructions}{syntax-instr-i31}{\K{i31.new}}
+.. |REFI31| mathdef:: \xref{syntax/instructions}{syntax-instr-i31}{\K{ref.i31}}
 .. |I31GET| mathdef:: \xref{syntax/instructions}{syntax-instr-i31}{\K{i31.get}}
 .. |I31GETS| mathdef:: \xref{syntax/instructions}{syntax-instr-i31}{\K{i31.get\_s}}
 .. |I31GETU| mathdef:: \xref{syntax/instructions}{syntax-instr-i31}{\K{i31.get\_u}}
@@ -1302,7 +1302,7 @@
 
 .. Administrative Instructions, terminals
 
-.. |REFI31| mathdef:: \xref{exec/runtime}{syntax-ref}{\K{ref{.}i31}}
+.. |REFI31NUM| mathdef:: \xref{exec/runtime}{syntax-ref}{\K{ref{.}i31}}
 .. |REFFUNCADDR| mathdef:: \xref{exec/runtime}{syntax-ref}{\K{ref{.}func}}
 .. |REFSTRUCTADDR| mathdef:: \xref{exec/runtime}{syntax-ref}{\K{ref{.}struct}}
 .. |REFARRAYADDR| mathdef:: \xref{exec/runtime}{syntax-ref}{\K{ref{.}array}}
diff --git a/document/core/valid/instructions.rst b/document/core/valid/instructions.rst
@@ -729,17 +729,17 @@ Aggregate Reference Instructions
 Scalar Reference Instructions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-.. _valid-i31.new:
+.. _valid-ref.i31:
 
-:math:`\I31NEW`
+:math:`\REFI31`
 ...............
 
 * The instruction is valid with type :math:`[\I32] \to [(\REF~\I31)]`.
 
 .. math::
    \frac{
    }{
-     C \vdashinstr \I31NEW : [\I32] \to [(\REF~\I31)]
+     C \vdashinstr \REFI31 : [\I32] \to [(\REF~\I31)]
    }
 
 .. _valid-i31.get_sx:
diff --git a/interpreter/binary/decode.ml b/interpreter/binary/decode.ml
@@ -625,7 +625,7 @@ let rec instr s =
     | 0x1al -> extern_internalize
     | 0x1bl -> extern_externalize
 
-    | 0x1cl -> i31_new
+    | 0x1cl -> ref_i31
     | 0x1dl -> i31_get_s
     | 0x1el -> i31_get_u
 
diff --git a/interpreter/binary/encode.ml b/interpreter/binary/encode.ml
@@ -385,7 +385,7 @@ struct
     | RefCast (NoNull, t) -> op 0xfb; op 0x16; heap_type t
     | RefCast (Null, t) -> op 0xfb; op 0x17; heap_type t
 
-    | I31New -> op 0xfb; op 0x1c
+    | RefI31 -> op 0xfb; op 0x1c
     | I31Get SX -> op 0xfb; op 0x1d
     | I31Get ZX -> op 0xfb; op 0x1e
 
diff --git a/interpreter/exec/eval.ml b/interpreter/exec/eval.ml
@@ -609,7 +609,7 @@ let rec step (c : config) : config =
       | RefEq, Ref r1 :: Ref r2 :: vs' ->
         value_of_bool (eq_ref r1 r2) :: vs', []
 
-      | I31New, Num (I32 i) :: vs' ->
+      | RefI31, Num (I32 i) :: vs' ->
         Ref (I31.I31Ref (I31.of_i32 i)) :: vs', []
 
       | I31Get ext, Ref (NullRef _) :: vs' ->
diff --git a/interpreter/syntax/ast.ml b/interpreter/syntax/ast.ml
@@ -201,7 +201,7 @@ and instr' =
   | RefTest of ref_type               (* type test *)
   | RefCast of ref_type               (* type cast *)
   | RefEq                             (* reference equality *)
-  | I31New                            (* allocate scalar *)
+  | RefI31                            (* scalar reference *)
   | I31Get of extension               (* read scalar *)
   | StructNew of idx * initop         (* allocate structure *)
   | StructGet of idx * idx * extension option  (* read structure field *)
diff --git a/interpreter/syntax/free.ml b/interpreter/syntax/free.ml
@@ -139,7 +139,7 @@ let rec instr (e : instr) =
   | RefEq -> empty
   | RefNull t -> heap_type t
   | RefFunc x -> funcs (idx x)
-  | I31New | I31Get _ -> empty
+  | RefI31 | I31Get _ -> empty
   | StructNew (x, _) | ArrayNew (x, _) | ArrayNewFixed (x, _) -> types (idx x)
   | ArrayNewElem (x, y) -> types (idx x) ++ elems (idx y)
   | ArrayNewData (x, y) -> types (idx x) ++ datas (idx y)
diff --git a/interpreter/syntax/operators.ml b/interpreter/syntax/operators.ml
@@ -108,7 +108,7 @@ let ref_test t = RefTest t
 let ref_cast t = RefCast t
 let ref_eq = RefEq
 
-let i31_new = I31New
+let ref_i31 = RefI31
 let i31_get_u = I31Get ZX
 let i31_get_s = I31Get SX
 let struct_new x = StructNew (x, Explicit)
diff --git a/interpreter/text/arrange.ml b/interpreter/text/arrange.ml
@@ -545,7 +545,7 @@ let rec instr e =
     | RefTest t -> "ref.test", [Atom (ref_type t)]
     | RefCast t -> "ref.cast", [Atom (ref_type t)]
     | RefEq -> "ref.eq", []
-    | I31New -> "i31.new", []
+    | RefI31 -> "ref.i31", []
     | I31Get ext -> "i31.get" ^ extension ext, []
     | StructNew (x, op) -> "struct.new" ^ initop op ^ " " ^ var x, []
     | StructGet (x, y, exto) ->
diff --git a/interpreter/text/lexer.mll b/interpreter/text/lexer.mll
@@ -308,7 +308,6 @@ rule token = parse
 
       | "ref.null" -> REF_NULL
       | "ref.func" -> REF_FUNC
-      | "ref.i31" -> REF_I31
       | "ref.struct" -> REF_STRUCT
       | "ref.array" -> REF_ARRAY
       | "ref.extern" -> REF_EXTERN
@@ -320,7 +319,7 @@ rule token = parse
       | "ref.cast" -> REF_CAST
       | "ref.eq" -> REF_EQ
 
-      | "i31.new" -> I31_NEW
+      | "ref.i31" -> REF_I31
       | "i31.get_u" -> I31_GET i31_get_u
       | "i31.get_s" -> I31_GET i31_get_s
 
diff --git a/interpreter/text/parser.mly b/interpreter/text/parser.mly
@@ -275,7 +275,7 @@ let inline_func_type_explicit (c : context) x ft at =
 %token<Ast.instr'> UNARY BINARY TEST COMPARE CONVERT
 %token REF_NULL REF_FUNC REF_I31 REF_STRUCT REF_ARRAY REF_EXTERN REF_HOST
 %token REF_EQ REF_IS_NULL REF_AS_NON_NULL REF_TEST REF_CAST
-%token I31_NEW
+%token REF_I31
 %token<Ast.instr'> I31_GET
 %token<Ast.idx -> Ast.instr'> STRUCT_NEW ARRAY_NEW ARRAY_GET
 %token STRUCT_SET
@@ -565,7 +565,7 @@ plain_instr :
   | REF_TEST ref_type { fun c -> ref_test ($2 c) }
   | REF_CAST ref_type { fun c -> ref_cast ($2 c) }
   | REF_EQ { fun c -> ref_eq }
-  | I31_NEW { fun c -> i31_new }
+  | REF_I31 { fun c -> ref_i31 }
   | I31_GET { fun c -> $1 }
   | STRUCT_NEW var { fun c -> $1 ($2 c type_) }
   | STRUCT_GET var var { fun c -> let x = $2 c type_ in $1 x ($3 c (field x.it)) }
diff --git a/interpreter/valid/valid.ml b/interpreter/valid/valid.ml
@@ -676,7 +676,7 @@ let rec check_instr (c : context) (e : instr) (s : infer_result_type) : infer_in
   | RefEq ->
     [RefT (Null, EqHT); RefT (Null, EqHT)] --> [NumT I32T], []
 
-  | I31New ->
+  | RefI31 ->
     [NumT I32T] --> [RefT (NoNull, I31HT)], []
 
   | I31Get ext ->
@@ -944,7 +944,7 @@ let is_const (c : context) (e : instr) =
   match e.it with
   | Const _ | VecConst _
   | RefNull _ | RefFunc _
-  | I31New | StructNew _ | ArrayNew _ | ArrayNewFixed _ -> true
+  | RefI31 | StructNew _ | ArrayNew _ | ArrayNewFixed _ -> true
   | GlobalGet x -> let GlobalT (mut, _t) = global c x in mut = Cons
   | _ -> false
 
diff --git a/proposals/gc/MVP.md b/proposals/gc/MVP.md
@@ -630,8 +630,8 @@ In particular, `ref.null` is typed as before, despite the introduction of `none`
 
 #### Unboxed Scalars
 
-* `i31.new` creates an `i31ref` from a 32 bit value, truncating high bit
-  - `i31.new : [i32] -> [(ref i31)]`
+* `ref.i31` creates an `i31ref` from a 32 bit value, truncating high bit
+  - `ref.i31 : [i32] -> [(ref i31)]`
   - this is a *constant instruction*
 
 * `i31.get_<sx>` extracts the value, zero- or sign-extending
@@ -703,7 +703,7 @@ Note: The [reference types](https://github.com/WebAssembly/reference-types) and
 
 In order to allow RTTs to be initialised as globals, the following extensions are made to the definition of *constant expressions*:
 
-* `i31.new` is a constant instruction
+* `ref.i31` is a constant instruction
 * `struct.new` and `struct.new_default` are constant instructions
 * `array.new`, `array.new_default`, and `array.new_fixed` are constant instructions
   - Note: `array.new_data` and `array.new_elem` are not for the time being, see above
@@ -834,7 +834,7 @@ The opcode for heap types is encoded as an `s33`.
 | 0xfb19 | `br_on_cast_fail $l (ref null1? ht1) (ref null2? ht2)` | `flags : u8`, $l : labelidx`, `ht1 : heaptype`, `ht2 : heaptype` |
 | 0xfb1a | `extern.internalize` |
 | 0xfb1b | `extern.externalize` |
-| 0xfb1c | `i31.new` |
+| 0xfb1c | `ref.i31` |
 | 0xfb1d | `i31.get_s` |
 | 0xfb1e | `i31.get_u` |
 
diff --git a/proposals/gc/Overview.md b/proposals/gc/Overview.md
@@ -350,7 +350,7 @@ However, compilation with a uniform representation can still be achieved in this
 (func $new_C (result (ref $C)) ...)
 (func $f
   ...
-  (call $make_pair (i31.new 1) (i31.new 0))
+  (call $make_pair (ref.i31 1) (ref.i31 0))
   ...
   (call $make_pair (call $new_C) (call $new_C))
   ...
@@ -607,7 +607,7 @@ To implement any such language efficiently, Wasm needs to provide such a mechani
 
 There are only three instructions for converting from and to this reference type:
 ```
-i31.new : [i32] -> [i31ref]
+ref.i31 : [i32] -> [i31ref]
 i31.get_u : [i31ref] -> [i32]
 i31.get_s : [i31ref] -> [i32]
 ```
diff --git a/test/core/gc/br_on_cast.wast b/test/core/gc/br_on_cast.wast
diff --git a/test/core/gc/br_on_cast_fail.wast b/test/core/gc/br_on_cast_fail.wast
diff --git a/test/core/gc/extern.wast b/test/core/gc/extern.wast
diff --git a/test/core/gc/i31.wast b/test/core/gc/i31.wast
diff --git a/test/core/gc/ref_cast.wast b/test/core/gc/ref_cast.wast
diff --git a/test/core/gc/ref_eq.wast b/test/core/gc/ref_eq.wast
diff --git a/test/core/gc/ref_test.wast b/test/core/gc/ref_test.wast
