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Update JS-API for resizable buffer integration #1961

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Merged
merged 6 commits into from
Sep 11, 2025
Merged

Update JS-API for resizable buffer integration #1961

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f172c2a
[js-api] Set the implementation limit for memory types
eqrion Aug 19, 2025
9b9c70c
[js-api] Don't allow memories without max in toResizableBuffer
eqrion Aug 19, 2025
9f0898b
[js-api] Remove unnecessary guard on maxsize
eqrion Aug 19, 2025
8c5737f
[js-api] Fix ordering of instructions
eqrion Aug 19, 2025
aba5735
[js-api] Fix units
eqrion Aug 19, 2025
c8b83b7
Fix Assert in memory.grow
eqrion Sep 10, 2025
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13 changes: 7 additions & 6 deletions document/js-api/index.bs
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Expand Up @@ -754,8 +754,6 @@ which can be simultaneously referenced by multiple {{Instance}} objects. Each

1. Let |block| be a [=Data Block=] which is [=identified with=] the underlying memory of |memaddr|.
1. Let |length| be the length of |block|.
1. If |maxsize| > (65536 × 65536),
1. Throw a {{RangeError}} exception.
1. Let |buffer| be a new {{ArrayBuffer}} with the internal slots \[[ArrayBufferData]], \[[ArrayBufferByteLength]], \[[ArrayBufferMaxByteLength]], and \[[ArrayBufferDetachKey]].
1. Set |buffer|.\[[ArrayBufferData]] to |block|.
1. Set |buffer|.\[[ArrayBufferByteLength]] to |length|.
Expand Down Expand Up @@ -860,15 +858,15 @@ Immediately after a WebAssembly [=memory.grow=] instruction executes, perform th

<div algorithm=dom-Memory-toResizableBuffer>
The <dfn method for="Memory">toResizableBuffer()</dfn> method, when invoked, performs the following steps:
1. If |memtype| does not have a max,
1. [=Throw=] a {{TypeError}} exception.
1. Let |buffer| be **this**.\[[BufferObject]].
1. If [=IsFixedLengthArrayBuffer=](|buffer|) is false, return |buffer|.
1. Let |memaddr| be **this**.\[[Memory]].
1. Let |store| be the [=surrounding agent=]'s [=associated store=].
1. Let |memtype| be [=mem_type=](|store|, |memaddr|).
1. If |memtype| has a max,
1. Let |maxsize| be the max value in |memtype|.
1. Otherwise,
1. Let |maxsize| be 65536 &times; 65536.
1. Assert |memtype| has a max.
1. Let |maxsize| be the max value in |memtype|.
1. Let |resizableBuffer| be the result of [=create a resizable memory buffer|creating a resizable memory buffer=] from |memaddr| and |maxsize|.
1. Perform [=!=] [$DetachArrayBuffer$](|buffer|, "WebAssembly.Memory").
1. Set **this**.\[[BufferObject]] to |resizableBuffer|.
Expand Down Expand Up @@ -1805,7 +1803,10 @@ In practice, an implementation may run out of resources for valid modules below
<li>The maximum number of tables, including declared or imported tables, is 100,000.</li>
<li>The maximum size of a table is 10,000,000.</li>
<li>The maximum number of table entries in any table initialization is 10,000,000.</li>

<li>The maximum number of memories, including defined and imported memories, is 100.</li>
<li>The maximum `min` or `max` field of a 32-bit memory is 65,536 pages (4 GiB).</li>
<li>The maximum `min` or `max` field of a 64-bit memory is 2^37-1 pages (2^53 - 2^16 bytes).</li>

<li>The maximum number of parameters to any function or block is 1,000.</li>
<li>The maximum number of return values for any function or block is 1,000.</li>
Expand Down