Merge pull request #7262 from xmake-io/pch

Improve pch concurrently to the other targets

3 files changed, 52 insertions, 10 deletions

diff --git a/xmake/modules/private/action/build/pcheader.lua b/xmake/modules/private/action/build/pcheader.lua
index 2e3210dca..4e984f62b 100644
--- a/xmake/modules/private/action/build/pcheader.lua
+++ b/xmake/modules/private/action/build/pcheader.lua
@@ -51,6 +51,9 @@ function config(target, langkind, opt)
                 target:pcheaderfile_set(langkind, headerfile)
             end
         end
+
+        -- enable precompiled header?
+        return true
     end
 end
 
diff --git a/xmake/rules/c++/precompiled_header/xmake.lua b/xmake/rules/c++/precompiled_header/xmake.lua
index a2b08fe46..8bfdd09dd 100644
--- a/xmake/rules/c++/precompiled_header/xmake.lua
+++ b/xmake/rules/c++/precompiled_header/xmake.lua
@@ -20,21 +20,46 @@
 
 rule("c.build.pcheader")
     on_config(function (target, opt)
-        import("private.action.build.pcheader").config(target, "c", opt)
+        import("private.action.build.pcheader")
+        if not pcheader.config(target, "c", opt) then
+            target:rule_enable("c.build.pcheader", false)
+        end
     end)
-    before_prepare(function (target, jobgraph, opt)
+
+    before_build(function (target, jobgraph, opt)
         if not os.getenv("XMAKE_IN_COMPILE_COMMANDS_PROJECT_GENERATOR") then
             import("private.action.build.pcheader").build(target, jobgraph, "c", opt)
         end
     end, {jobgraph = true})
 
 rule("c++.build.pcheader")
-    add_orders("c++.build.modules.scanner", "c++.build.pcheader", "c++.build.modules.builder")
     on_config(function (target, opt)
-        import("private.action.build.pcheader").config(target, "cxx", opt)
+        import("private.action.build.pcheader")
+        if not pcheader.config(target, "cxx", opt) then
+            target:rule_enable("c++.build.pcheader", false)
+        end
     end)
+
+    -- If the current target has a C++ modules file,
+    -- we can only compile it earlier in the before_prepare stage,
+    -- because the C++ modules will perform a complete dependency scan of
+    -- the C++ files in on_prepare and then build the dependency graph.
+    -- At this time, the pch header file must have already been generated.
     before_prepare(function (target, jobgraph, opt)
-        if not os.getenv("XMAKE_IN_COMPILE_COMMANDS_PROJECT_GENERATOR") then
+        local has_modules = target:data("cxx.has_modules")
+        if has_modules and not os.getenv("XMAKE_IN_COMPILE_COMMANDS_PROJECT_GENERATOR") then
+            import("private.action.build.pcheader").build(target, jobgraph, "cxx", opt)
+        end
+    end, {jobgraph = true})
+
+    -- To enable parallel compilation across targets
+    -- without blocking the compilation of other cpp files,
+    -- we perform this as much as possible during the before_build stage.
+    --
+    -- @see: https://github.com/xmake-io/xmake/issues/4167
+    before_build(function (target, jobgraph, opt)
+        local has_modules = target:data("cxx.has_modules")
+        if not has_modules then
             import("private.action.build.pcheader").build(target, jobgraph, "cxx", opt)
         end
     end, {jobgraph = true})
diff --git a/xmake/rules/objc++/precompiled_header/xmake.lua b/xmake/rules/objc++/precompiled_header/xmake.lua
index ed0eda0a4..5dafb0e84 100644
--- a/xmake/rules/objc++/precompiled_header/xmake.lua
+++ b/xmake/rules/objc++/precompiled_header/xmake.lua
@@ -20,18 +20,32 @@
 
 rule("objc.build.pcheader")
     on_config(function (target, opt)
-        import("private.action.build.pcheader").config(target, "m", opt)
+        import("private.action.build.pcheader")
+        if not pcheader.config(target, "m", opt) then
+            target:rule_enable("objc.build.pcheader", false)
+        end
     end)
-    before_prepare(function (target, jobgraph, opt)
-        import("private.action.build.pcheader").build(target, jobgraph, "m", opt)
+
+    before_build(function (target, jobgraph, opt)
+        if not os.getenv("XMAKE_IN_COMPILE_COMMANDS_PROJECT_GENERATOR") then
+            import("private.action.build.pcheader").build(target, jobgraph, "m", opt)
+        end
     end, {jobgraph = true})
 
 rule("objc++.build.pcheader")
     add_orders("objc++.build.pcheader", "c++.build.modules.builder")
     on_config(function (target, opt)
-        import("private.action.build.pcheader").config(target, "mxx", opt)
+        import("private.action.build.pcheader")
+        if not pcheader.config(target, "mxx", opt) then
+            target:rule_enable("objc++.build.pcheader", false)
+        end
     end)
-    before_prepare(function (target, jobgraph, opt)
+
+    -- Since Objective-C typically does not have C++ modules,
+    -- we can always enable parallel compilation across targets
+    -- without blocking the compilation of other cpp files,
+    -- we perform this as much as possible during the before_build stage.
+    before_build(function (target, jobgraph, opt)
         import("private.action.build.pcheader").build(target, jobgraph, "mxx", opt)
     end, {jobgraph = true})