add xbyak (#1000)

* add xbyak

* Update xmake.lua

packages/x/xbyak/xmake.lua

@@ -0,0 +1,27 @@
+package("xbyak")
+
+    set_kind("library", {headeronly = true})
+    set_homepage("https://github.com/herumi/xbyak")
+    set_description("A JIT assembler for x86(IA-32)/x64(AMD64, x86-64) MMX/SSE/SSE2/SSE3/SSSE3/SSE4/FPU/AVX/AVX2/AVX-512 by C++ header")
+
+    set_urls("https://github.com/herumi/xbyak/archive/$(version).zip",
+             "https://github.com/herumi/xbyak.git")
+
+    add_versions("v6.02", "cd3fe5ee15df6bfa73c721584b101c885096551124e6ded31b6f866ecb381cf0")
+
+    on_install(function (package)
+        os.cp("xbyak", package:installdir("include"))
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            void test()
+            {
+                class Sample : public Xbyak::CodeGenerator {
+                    Sample() {
+                      inc(eax);
+                    }
+                };
+            }
+        ]]}, {configs = {languages = "c++17"}, includes = { "xbyak/xbyak.h" } }))
+    end)