gn build: Rebase clang-tblgen include path against root_build_dir instead of root_out_dir.

Fixes clang cross-compilation.

Also remove some redundant include path arguments.

llvm/utils/gn/secondary/clang/include/clang/Basic/BUILD.gn

@@ -63,29 +63,17 @@ clang_tablegen("DiagnosticIndexName") {
 # Attributes
 
 clang_tablegen("AttrList") {
-  args = [
-    "-gen-clang-attr-list",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-list" ]
   td_file = "Attr.td"
 }
 
 clang_tablegen("AttrSubMatchRulesList") {
-  args = [
-    "-gen-clang-attr-subject-match-rule-list",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-subject-match-rule-list" ]
   td_file = "Attr.td"
 }
 
 clang_tablegen("AttrHasAttributeImpl") {
-  args = [
-    "-gen-clang-attr-has-attribute-impl",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-has-attribute-impl" ]
   td_file = "Attr.td"
 }
 

llvm/utils/gn/secondary/clang/include/clang/Parse/BUILD.gn

@@ -1,19 +1,11 @@
 import("//clang/utils/TableGen/clang_tablegen.gni")
 
 clang_tablegen("AttrParserStringSwitches") {
-  args = [
-    "-gen-clang-attr-parser-string-switches",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-parser-string-switches" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrSubMatchRulesParserStringSwitches") {
-  args = [
-    "-gen-clang-attr-subject-match-rules-parser-string-switches",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-subject-match-rules-parser-string-switches" ]
   td_file = "../Basic/Attr.td"
 }

llvm/utils/gn/secondary/clang/include/clang/Sema/BUILD.gn

@@ -1,46 +1,26 @@
 import("//clang/utils/TableGen/clang_tablegen.gni")
 
 clang_tablegen("AttrTemplateInstantiate") {
-  args = [
-    "-gen-clang-attr-template-instantiate",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-template-instantiate" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrParsedAttrList") {
-  args = [
-    "-gen-clang-attr-parsed-attr-list",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-parsed-attr-list" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrParsedAttrKinds") {
-  args = [
-    "-gen-clang-attr-parsed-attr-kinds",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-parsed-attr-kinds" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrSpellingListIndex") {
-  args = [
-    "-gen-clang-attr-spelling-index",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-spelling-index" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrParsedAttrImpl") {
-  args = [
-    "-gen-clang-attr-parsed-attr-impl",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-parsed-attr-impl" ]
   td_file = "../Basic/Attr.td"
 }

llvm/utils/gn/secondary/clang/include/clang/Serialization/BUILD.gn

@@ -1,19 +1,11 @@
 import("//clang/utils/TableGen/clang_tablegen.gni")
 
 clang_tablegen("AttrPCHRead") {
-  args = [
-    "-gen-clang-attr-pch-read",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-pch-read" ]
   td_file = "../Basic/Attr.td"
 }
 
 clang_tablegen("AttrPCHWrite") {
-  args = [
-    "-gen-clang-attr-pch-write",
-    "-I",
-    rebase_path("../..", root_out_dir),
-  ]
+  args = [ "-gen-clang-attr-pch-write" ]
   td_file = "../Basic/Attr.td"
 }

llvm/utils/gn/secondary/clang/utils/TableGen/clang_tablegen.gni

@@ -36,7 +36,7 @@ template("clang_tablegen") {
 
     args = [
              "-I",
-             rebase_path("//clang/include", root_out_dir),
+             rebase_path("//clang/include", root_build_dir),
            ] + invoker.args
     tblgen_target = "//clang/utils/TableGen:clang-tblgen"
   }