[xsimd] Add new port (microsoft#5194)

* [xsimd] Add new port

* Add a header include guard to xsimd's algorithm.hpp

algorithm.hpp is not guarded by a header include guard, which can cause
difficulty for users. xhihaoy asked that we be sure to include this
patch because it caused a lot of pain.

ports/xsimd/CONTROL

@@ -0,0 +1,7 @@
+Source: xsimd
+Version: 7.1.2
+Description: Modern, portable C++ wrappers for SIMD intrinsics
+
+Feature: xcomplex
+Description: xtl complex support
+Build-Depends: xtl

ports/xsimd/PatchHeaderIncludeGuard.patch

@@ -0,0 +1,24 @@
+diff --git a/include/xsimd/stl/algorithms.hpp b/include/xsimd/stl/algorithms.hpp
+index 4cb2b79..1590b89 100644
+--- a/include/xsimd/stl/algorithms.hpp
++++ b/include/xsimd/stl/algorithms.hpp
+@@ -6,6 +6,9 @@
+ * The full license is in the file LICENSE, distributed with this software. *
+ ****************************************************************************/
+
++#ifndef XSIMD_ALGORITHMS_HPP
++#define XSIMD_ALGORITHMS_HPP
++
+ #include "xsimd/memory/xsimd_load_store.hpp"
+
+ namespace xsimd
+@@ -126,4 +129,6 @@ namespace xsimd
+
+         #undef XSIMD_LOOP_MACRO
+     }
+-}
+\ No newline at end of file
++}
++
++#endif
+\ No newline at end of file

ports/xsimd/portfile.cmake

@@ -0,0 +1,40 @@
+# header-only library
+
+include(vcpkg_common_functions)
+
+vcpkg_from_github(
+    OUT_SOURCE_PATH SOURCE_PATH
+    REPO QuantStack/xsimd
+    REF 7.1.2
+    SHA512 9479eb6188a68388d470e38ec7b08aaeeb03a1028a574258b52e1c39ce0b1b1aaf97a5cb898447f68c989badd23903ba7a059f5daf59160c660ba751d668c0eb
+    HEAD_REF master
+    PATCHES PatchHeaderIncludeGuard.patch
+)
+
+if("xcomplex" IN_LIST FEATURES)
+    set(ENABLE_XTL_COMPLEX ON)
+else()
+    set(ENABLE_XTL_COMPLEX OFF)
+endif()
+
+vcpkg_configure_cmake(
+    SOURCE_PATH ${SOURCE_PATH}
+    PREFER_NINJA
+    OPTIONS
+        -DENABLE_FALLBACK=OFF
+        -DENABLE_XTL_COMPLEX=${ENABLE_XTL_COMPLEX}
+        -DBUILD_TESTS=OFF
+        -DDOWNLOAD_GTEST=OFF
+)
+
+vcpkg_install_cmake()
+
+vcpkg_fixup_cmake_targets(CONFIG_PATH lib/cmake/${PORT})
+
+file(REMOVE_RECURSE ${CURRENT_PACKAGES_DIR}/debug ${CURRENT_PACKAGES_DIR}/lib)
+
+# Handle copyright
+configure_file(${SOURCE_PATH}/LICENSE ${CURRENT_PACKAGES_DIR}/share/${PORT}/copyright COPYONLY)
+
+# CMake integration test
+vcpkg_test_cmake(PACKAGE_NAME ${PORT})