From 26c651c34e65558bbfb850a1a1b7f2e922dcbea9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micha=C3=ABl=20Zasso?= Date: Sun, 25 Sep 2022 17:35:07 +0200 Subject: [PATCH] deps: V8: cherry-pick 1b3a4f0c34a1 Original commit message: [msvc] fix build with neon intrinsics This compilation error was found by NodeJS when updating V8: https://github.com/nodejs/node-v8/issues/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 Reviewed-by: Jakob Kummerow Commit-Queue: Jakob Kummerow Cr-Commit-Position: refs/heads/main@{#83404} Refs: https://github.com/v8/v8/commit/1b3a4f0c34a19ea82958823c400068a7dbc63675 PR-URL: https://github.com/nodejs/node/pull/44741 Reviewed-By: Ben Noordhuis Reviewed-By: Jiawen Geng Reviewed-By: James M Snell --- common.gypi | 2 +- deps/v8/src/objects/simd.cc | 30 +++++++++++++++++++----------- 2 files changed, 20 insertions(+), 12 deletions(-) diff --git a/common.gypi b/common.gypi index af5098d898109d..05b742910325cd 100644 --- a/common.gypi +++ b/common.gypi @@ -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 ##### diff --git a/deps/v8/src/objects/simd.cc b/deps/v8/src/objects/simd.cc index 22467cace00fc2..54dd3a0809bbf9 100644 --- a/deps/v8/src/objects/simd.cc +++ b/deps/v8/src/objects/simd.cc @@ -89,21 +89,29 @@ inline uintptr_t slow_search(T* array, uintptr_t array_len, uintptr_t index, // max(v & mask) = 4 // index of the first match = 4-max = 4-4 = 0 // -template -inline int extract_first_nonzero_index(T v) { - UNREACHABLE(); -} -template <> -V8_ALLOW_UNUSED inline int extract_first_nonzero_index(uint32x4_t v) { - uint32x4_t mask = {4, 3, 2, 1}; +// With MSVC, uint32x4_t and uint64x2_t typedef to a union, where first member +// is uint64_t[2], and not uint32_t[4]. +// C++ standard dictates that a union can only be initialized through its first +// member, which forces us to have uint64_t[2] for definition. +#if defined(_MSC_VER) +#define PACK32x4(w, x, y, z) \ + { ((w) + (uint64_t(x) << 32)), ((y) + (uint64_t(z) << 32)) } +#else +#define PACK32x4(w, x, y, z) \ + { (w), (x), (y), (z) } +#endif // MSVC workaround + +V8_ALLOW_UNUSED inline int extract_first_nonzero_index_uint32x4_t( + uint32x4_t v) { + uint32x4_t mask = PACK32x4(4, 3, 2, 1); mask = vandq_u32(mask, v); return 4 - vmaxvq_u32(mask); } -template <> -inline int extract_first_nonzero_index(uint64x2_t v) { - uint32x4_t mask = {2, 0, 1, 0}; // Could also be {2,2,1,1} or {0,2,0,1} +inline int extract_first_nonzero_index_uint64x2_t(uint64x2_t v) { + uint32x4_t mask = + PACK32x4(2, 0, 1, 0); // Could also be {2,2,1,1} or {0,2,0,1} mask = vandq_u32(mask, vreinterpretq_u32_u64(v)); return 2 - vmaxvq_u32(mask); } @@ -122,7 +130,7 @@ inline int32_t reinterpret_vmaxvq_u64(uint64x2_t v) { type_load vector = *reinterpret_cast(&array[index]); \ type_eq eq = cmp(vector, search_element_vec); \ if (movemask(eq)) { \ - return index + extract_first_nonzero_index(eq); \ + return index + extract_first_nonzero_index_##type_eq(eq); \ } \ } \ }