optimize loadfile again, decreate 98% startup time

2 files changed, 16 insertions, 8 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4b345629d..f1f3ad3e9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,7 +16,7 @@
 
 * Improve remote package manager
 * Improve `target:on_xxx` scripts to support to match `android|armv7-a@macosx,linux|x86_64` pattern
-* Improve loadfile to optimize startup speed
+* Improve loadfile to optimize startup speed, decrease 98% time
 
 ### Bugs fixed
 
@@ -596,7 +596,7 @@
 
 * 改进远程依赖包管理，丰富包仓库
 * 改进`target:on_xxx`自定义脚本，去支持匹配`android|armv7-a@macosx,linux|x86_64`模式
-* 改进loadfile，优化启动速度，windows上启动xmake提速30%
+* 改进loadfile，优化启动速度，windows上启动xmake时间提速98%
 
 ### Bugs修复
 
diff --git a/xmake/core/_xmake_main.lua b/xmake/core/_xmake_main.lua
index 760ea4dc8..7833e1687 100644
--- a/xmake/core/_xmake_main.lua
+++ b/xmake/core/_xmake_main.lua
@@ -34,14 +34,22 @@ xmake._PROJECT_FILE     = "xmake.lua"
 local _loadfile = _loadfile or loadfile
 local _loadcache = {}
 function loadfile(filepath)
-    local errors = nil
-    local script = _loadcache[filepath]
-    if script == nil then
-        script, errors = _loadfile(filepath)
-        if script and filepath:startswith(_PROGRAM_DIR) then
-            _loadcache[filepath] = script
+
+    -- attempt to load script from cache first
+    local mtime = nil
+    local cache = _loadcache[filepath]
+    if cache and cache.script then
+        mtime = os.mtime(filepath)
+        if mtime > 0 and cache.mtime == mtime then
+            return cache.script, nil
         end
     end
+
+    -- load script from file
+    local script, errors = _loadfile(filepath)
+    if script then
+        _loadcache[filepath] = {script = script, mtime = mtime or os.mtime(filepath)}
+    end
     return script, errors
 end