From: Yurii Hordiienko <45203053+hordi@users.noreply.github.com>
Date: Thu, 24 Nov 2022 13:51:40 +0000 (-0500)
Subject: Update unicoder.cpp (#1584)
X-Git-Tag: 2.16.24+jp-2~2^2~5
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=c966793684f79c2de6f1a33b12416759d54f19f5;p=winmerge-jp%2Fwinmerge-jp.git

Update unicoder.cpp (#1584)

CheckForInvalidUtf8 performance improvement
---

diff --git a/Src/Common/unicoder.cpp b/Src/Common/unicoder.cpp
index e499db296..37f2381ec 100644
--- a/Src/Common/unicoder.cpp
+++ b/Src/Common/unicoder.cpp
@@ -1134,18 +1134,19 @@ bool CheckForInvalidUtf8(const char* pBuffer, size_t size)
 	for (unsigned char* pb = (unsigned char*)pBuffer, *end = pb + size; pb < end;)
 	{
 		unsigned c = *pb++;
-		if ((c == 0xC0) || (c == 0xC1) || (c >= 0xF5))
-			return true;
-
+		
 		if (!(c & 0x80)) continue;
+		
+		if ((c >= 0xF5) || (c == 0xC0) || (c == 0xC1))
+			return true;
 
-		uint32_t v = 0x80808080;
+		uint32_t v = 0x80808000; //1st 0-byte covers scenario if no any next "if" fired at all
 
 		if ((c & 0xE0) == 0xC0)
 		{
 			if (pb == end)
 				return true;
-			reinterpret_cast<unsigned char*>(&v)[0] = *pb++;
+			*reinterpret_cast<unsigned char*>(&v) = *pb++;
 		}
 		else if ((c & 0xF0) == 0xE0)
 		{
@@ -1164,8 +1165,6 @@ bool CheckForInvalidUtf8(const char* pBuffer, size_t size)
 			reinterpret_cast<uint8_t*>(&v)[2] = pb[2];
 			pb += 3;
 		}
-		else
-			return true;
 
 		if ((v & (0xC0C0C0C0)) != 0x80808080)
 			return true;