!16 fix alignment code in SSE4.2-optimized CRC32C

From: @ikernel-mryao 
Reviewed-by: @Charlie_li 
Signed-off-by: @Charlie_li

0006-leveldb-Fix-alignment-code-in-SSE4.2-optimized-CRC32.patch

@@ -0,0 +1,40 @@
+From 2964b803b857932ff7499d7bebb61dc5514dab7c Mon Sep 17 00:00:00 2001
+From: costan <costan@google.com>
+Date: Wed, 23 Aug 2017 20:59:46 -0700
+Subject: [PATCH] leveldb: Fix alignment code in SSE4.2-optimized CRC32C.
+
+When faced with a pointer that is misaligned by K bytes (pointer % 8 ==
+K), the code previously moved forward by K bytes. In order to end up
+with an aligned pointer, the code must move by 8 - K bytes.
+
+This lands https://github.com/google/leveldb/pull/488
+
+-------------
+Created by MOE: https://github.com/google/moe
+MOE_MIGRATED_REVID=166295921
+---
+ port/port_posix_sse.cc | 8 ++++++--
+ 1 file changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/port/port_posix_sse.cc b/port/port_posix_sse.cc
+index 1e519ba..08d9aee 100644
+--- a/port/port_posix_sse.cc
++++ b/port/port_posix_sse.cc
+@@ -92,8 +92,12 @@ uint32_t AcceleratedCRC32C(uint32_t crc, const char* buf, size_t size) {
+ } while (0)
+ 
+   if (size > 16) {
+-    // Process unaligned bytes
+-    for (unsigned int i = reinterpret_cast<uintptr_t>(p) % 8; i; --i) {
++    // Point x at first 8-byte aligned byte in string. This must be inside the
++    // string, due to the size check above.
++    const uintptr_t pval = reinterpret_cast<uintptr_t>(p);
++    const uint8_t* x = reinterpret_cast<const uint8_t*>(((pval + 7) >> 3) << 3);
++    // Process bytes until p is 8-byte aligned.
++    while (p != x) {
+       STEP1;
+     }
+ 
+-- 
+2.40.0.windows.1
+

leveldb.spec

@@ -1,6 +1,6 @@
 Name:           leveldb
 Version:        1.20
-Release:        5
+Release:        6
 Summary:        A key/value database library
 License:        BSD
 URL:            https://github.com/google/leveldb
@@ -11,6 +11,7 @@ Patch0002:      0002-Added-a-DB-SuspendCompations-and-DB-ResumeCompaction.patch
 Patch0003:      0003-allow-Get-calls-to-avoid-copies-into-std-string.patch
 Patch0004:      0004-bloom_test-failure-on-big-endian-archs.patch
 Patch0005:      0005-broken-db-fix-assertion-in-leveldb-InternalKey-Encod.patch
+Patch0006:      0006-leveldb-Fix-alignment-code-in-SSE4.2-optimized-CRC32.patch
 
 BuildRequires:  make gcc-c++ snappy-devel
 
@@ -72,6 +73,9 @@ make -j1 check
 %{_libdir}/pkgconfig/leveldb.pc
 
 %changelog
+* Tue Apr 25 2023 yaoguangzhong <yaoguangzhong@xfusion.com> -  1.20-6
+- fix alignment code in SSE4.2-optimized CRC32C
+
 * Tue Apr 18 2023 yaoguangzhong <yaoguangzhong@xfusion.com> -  1.20-5
 - fix assertion in leveldb::InternalKey::Encode, mark base as corrupt