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deps: V8: cherry-pick 1b3a4f0c34a1
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Original commit message:

    [msvc] fix build with neon intrinsics

    This compilation error was found by NodeJS when updating V8:
    #240

    MSVC reports an error with "too many initializer" for type uint32x4_t.

    ---

    Under gcc/clang, this is a typedef to a builtin type.

    For MSVC, it is a typedef to this union:
    typedef union __n128
    {
         unsigned __int64   n128_u64[2];
         unsigned __int32   n128_u32[4];
         ...
    } __n128;

    C++ mandates that only first member of union can be initialized at
    declaration. Thus, it can only be initialized with {uint64_t, uint64_t}.

    VS people proposed to use designated initializer instead:
    var = {.n128_u32={1, 2, 3, 8}}
    https://developercommunity.visualstudio.com/t/error-c2078-too-many-initializers-when-using-arm-n/402911
    But, you need to use /std:c++20 for this, which is not the case in v8.

    ---

    Thus, the only solution is to implement a hack specifically for MSVC,
    where you build two uint64, from four uint32.

    ---------------------------------------

    Once solved, another error is reported:
    templated function extract_first_nonzero_index is specialized twice.

    This is because, with MSVC, uint32x4_t and uint64x2_t are typedef to the
    same __n128 union. The fix is to drop templates, and use explicit
    function names instead.

    Bug: v8:13312
    Change-Id: I231d8cf01c05af01af319d56d5666c415f8b989b
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3913035
    Reviewed-by: Igor Sheludko <ishell@chromium.org>
    Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
    Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#83404}

Refs: v8/v8@1b3a4f0
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targos authored and nodejs-github-bot committed Sep 29, 2022
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2 changes: 1 addition & 1 deletion common.gypi
Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@

# Reset this number to 0 on major V8 upgrades.
# Increment by one for each non-official patch applied to deps/v8.
'v8_embedder_string': '-node.8',
'v8_embedder_string': '-node.9',

##### V8 defaults for Node.js #####

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