From 52cd98769ea0425346320d9d8e6671f46ea1d12f Mon Sep 17 00:00:00 2001
From: Attila Afra <attila.t.afra@intel.com>
Date: Fri, 1 Feb 2019 12:42:57 +0200
Subject: [PATCH] lowered the ISA requirement from SSE4.2 to SSE4.1

---
 CHANGELOG.md     | 1 +
 CMakeLists.txt   | 6 +++---
 core/device.cpp  | 4 ++--
 doc/api.md       | 2 +-
 doc/downloads.md | 2 +-
 doc/overview.md  | 2 +-
 mkl-dnn          | 2 +-
 7 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a1f604f2..f54534d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ Version History
 
 -   Fixed wrong path in the generated CMake config
 -   Fixed wrong rpath in the binaries
+-   Lowered the CPU requirement to SSE4.1
 
 ### Changes in v0.8.0:
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f0f0073d..90c9ff8c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -141,12 +141,12 @@ generate_cpp_resources(WEIGHTS_SOURCES "oidn::weights"
 
 add_library(${PROJECT_NAME} SHARED ${CORE_SOURCES} ${WEIGHTS_SOURCES})
 
-add_library("${PROJECT_NAME}_sse42" STATIC ${CORE_SOURCES_SSE42})
-set_target_properties("${PROJECT_NAME}_sse42" PROPERTIES COMPILE_FLAGS "${ISA_FLAGS_SSE42}")
+add_library("${PROJECT_NAME}_sse41" STATIC ${CORE_SOURCES_SSE42})
+set_target_properties("${PROJECT_NAME}_sse41" PROPERTIES COMPILE_FLAGS "${ISA_FLAGS_SSE41}")
 
 target_link_libraries(${PROJECT_NAME}
   PRIVATE
-    "${PROJECT_NAME}_sse42"
+    "${PROJECT_NAME}_sse41"
     common mkldnn
     ${TBB_LIBRARIES}
 )
diff --git a/core/device.cpp b/core/device.cpp
index ffd02b30..608f94a1 100644
--- a/core/device.cpp
+++ b/core/device.cpp
@@ -23,8 +23,8 @@ namespace oidn {
 
   Device::Device()
   {
-    if (!mayiuse(sse42))
-      throw Exception(Error::UnsupportedHardware, "SSE4.2 support is required at minimum");
+    if (!mayiuse(sse41))
+      throw Exception(Error::UnsupportedHardware, "SSE4.1 support is required at minimum");
   }
 
   Device::~Device()
diff --git a/doc/api.md b/doc/api.md
index 774094cd..c3ac1ff5 100644
--- a/doc/api.md
+++ b/doc/api.md
@@ -99,7 +99,7 @@ can be one of the following:
 Name                     Description
 ------------------------ ------------------------------------------------------
 OIDN_DEVICE_TYPE_DEFAULT select the approximately fastest device
-OIDN_DEVICE_TYPE_CPU     CPU device (requires SSE4.2 support)
+OIDN_DEVICE_TYPE_CPU     CPU device (requires SSE4.1 support)
 ------------------------ ------------------------------------------------------
 : Supported device types, i.e., valid constants of type `OIDNDeviceType`.
 
diff --git a/doc/downloads.md b/doc/downloads.md
index ccbb59f1..eedbc38e 100644
--- a/doc/downloads.md
+++ b/doc/downloads.md
@@ -4,7 +4,7 @@ Download Precompiled Open Image Denoise Binary Packages
 Prerequisites
 -------------
 
-Your CPU must support at least SSE4.2 to run Open Image Denoise, and you need
+Your CPU must support at least SSE4.1 to run Open Image Denoise, and you need
 a 64-bit operating system as well. The TGZ/ZIP packages contain most needed
 3rd party dependencies.
 
diff --git a/doc/overview.md b/doc/overview.md
index 81cd9612..b0765f44 100644
--- a/doc/overview.md
+++ b/doc/overview.md
@@ -24,7 +24,7 @@ ray tracing.
 Open Image Denoise internally builds on top of
 [Intel® Math Kernel Library for Deep Neural Networks (MKL-DNN)](https://github.com/intel/mkl-dnn),
 and fully exploits modern instruction sets like Intel SSE4, AVX2, and AVX-512
-to achieve high denoising performance. A CPU with support for at least SSE4.2
+to achieve high denoising performance. A CPU with support for at least SSE4.1
 is required to run Open Image Denoise.
 
 
diff --git a/mkl-dnn b/mkl-dnn
index ad659f03..cdbcddd5 160000
--- a/mkl-dnn
+++ b/mkl-dnn
@@ -1 +1 @@
-Subproject commit ad659f033920724f8bc9ab5f6ba367c0b8697b8a
+Subproject commit cdbcddd53b3b83ef72d6a1bf6ea513c1598211b5