Merge pull request #38530 from akien-mga/jpgd-fix-msvc-sse2-detection

jpgd: Fix detection of SSE2 support with MSVC

thirdparty/jpeg-compressor/jpgd.cpp

@@ -37,16 +37,14 @@
 
 #ifndef JPGD_USE_SSE2
 
-	#if defined(__GNUC__) 
-
-		#if (defined(__x86_64__) || defined(_M_X64)) 
-			#if defined(__SSE2__)
-				#define JPGD_USE_SSE2 (1)
-			#endif
+	#if defined(__GNUC__)
+		#if defined(__SSE2__)
+			#define JPGD_USE_SSE2 (1)
+		#endif
+	#elif defined(_MSC_VER)
+		#if defined(_M_X64)
+			#define JPGD_USE_SSE2 (1)
 		#endif
-
-	#else
-		#define JPGD_USE_SSE2 (1)
 	#endif
 
 #endif

thirdparty/jpeg-compressor/patches/fix-msvc-sse2-detection.patch

@@ -0,0 +1,44 @@
+From ae74fa2fcdef8ec44b925a649f66e8cbefce8315 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?R=C3=A9mi=20Verschelde?= <[email protected]>
+Date: Thu, 7 May 2020 12:14:09 +0200
+Subject: [PATCH] Fix detection of SSE2 with Visual Studio
+
+The previous code assumed that SSE2 is available when building with
+Visual Studio, but that's not accurate on ARM with UWP.
+
+SSE2 could also be enabled on x86 if `_M_IX86_FP == 2`, but it requires
+checking first that it's not actually set to 2 for AVX, AVX2 or AVX512
+(see https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros?view=vs-2019),
+so I left it out for this quick fix.
+---
+ jpgd.cpp | 16 +++++++---------
+ 1 file changed, 7 insertions(+), 9 deletions(-)
+
+diff --git a/jpgd.cpp b/jpgd.cpp
+index 91e66ad..db1f3b4 100644
+--- a/jpgd.cpp
++++ b/jpgd.cpp
+@@ -37,16 +37,14 @@
+ 
+ #ifndef JPGD_USE_SSE2
+ 
+-	#if defined(__GNUC__) 
+-
+-		#if (defined(__x86_64__) || defined(_M_X64)) 
+-			#if defined(__SSE2__)
+-				#define JPGD_USE_SSE2 (1)
+-			#endif
++	#if defined(__GNUC__)
++		#if defined(__SSE2__)
++			#define JPGD_USE_SSE2 (1)
++		#endif
++	#elif defined(_MSC_VER)
++		#if defined(_M_X64)
++			#define JPGD_USE_SSE2 (1)
+ 		#endif
+-
+-	#else
+-		#define JPGD_USE_SSE2 (1)
+ 	#endif
+ 
+ #endif