From 2c01333d03153a2d3cc2622fa18a9ad323dd9edb Mon Sep 17 00:00:00 2001 From: Piotr Caban Date: Thu, 16 Sep 2021 13:51:58 +0200 Subject: [PATCH] msvcrt: Use unaligned data types in memset. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This fixes a regression in memset on ARM described by Martin: ARM can do 64 bit writes with the STRD instruction, but that instruction requires a 32 bit aligned address - while these stores are unaligned. Signed-off-by: Piotr Caban Signed-off-by: Martin Storsjö Signed-off-by: Alexandre Julliard --- dlls/msvcrt/string.c | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) diff --git a/dlls/msvcrt/string.c b/dlls/msvcrt/string.c index f2b1b4a5b11..5655fbfe68a 100644 --- a/dlls/msvcrt/string.c +++ b/dlls/msvcrt/string.c @@ -2872,21 +2872,25 @@ static inline void memset_aligned_32(unsigned char *d, uint64_t v, size_t n) */ void *__cdecl memset(void *dst, int c, size_t n) { + typedef uint64_t DECLSPEC_ALIGN(1) unaligned_ui64; + typedef uint32_t DECLSPEC_ALIGN(1) unaligned_ui32; + typedef uint16_t DECLSPEC_ALIGN(1) unaligned_ui16; + uint64_t v = 0x101010101010101ull * (unsigned char)c; unsigned char *d = (unsigned char *)dst; size_t a = 0x20 - ((uintptr_t)d & 0x1f); if (n >= 16) { - *(uint64_t *)(d + 0) = v; - *(uint64_t *)(d + 8) = v; - *(uint64_t *)(d + n - 16) = v; - *(uint64_t *)(d + n - 8) = v; + *(unaligned_ui64 *)(d + 0) = v; + *(unaligned_ui64 *)(d + 8) = v; + *(unaligned_ui64 *)(d + n - 16) = v; + *(unaligned_ui64 *)(d + n - 8) = v; if (n <= 32) return dst; - *(uint64_t *)(d + 16) = v; - *(uint64_t *)(d + 24) = v; - *(uint64_t *)(d + n - 32) = v; - *(uint64_t *)(d + n - 24) = v; + *(unaligned_ui64 *)(d + 16) = v; + *(unaligned_ui64 *)(d + 24) = v; + *(unaligned_ui64 *)(d + n - 32) = v; + *(unaligned_ui64 *)(d + n - 24) = v; if (n <= 64) return dst; n = (n - a) & ~0x1f; @@ -2895,20 +2899,20 @@ void *__cdecl memset(void *dst, int c, size_t n) } if (n >= 8) { - *(uint64_t *)d = v; - *(uint64_t *)(d + n - 8) = v; + *(unaligned_ui64 *)d = v; + *(unaligned_ui64 *)(d + n - 8) = v; return dst; } if (n >= 4) { - *(uint32_t *)d = v; - *(uint32_t *)(d + n - 4) = v; + *(unaligned_ui32 *)d = v; + *(unaligned_ui32 *)(d + n - 4) = v; return dst; } if (n >= 2) { - *(uint16_t *)d = v; - *(uint16_t *)(d + n - 2) = v; + *(unaligned_ui16 *)d = v; + *(unaligned_ui16 *)(d + n - 2) = v; return dst; } if (n >= 1)