Add tidy_disabled_srcs property.

Used as a supplement to C/C++ srcs to disable
clang-tidy for selected srcs, when a library
contains many files in srcs and only some of them
are too large to compile with clang-tidy.

Test: WITH_TIDY=1 TIDY_TIMEOUT=90 make tidy-soong
Bug: 198098397
Change-Id: Ib32eb0e46ddbc717999797717bfd8c57e182ee88

cc/builder.go

@@ -454,15 +454,19 @@ func escapeSingleQuotes(s string) string {
 }
 
 // Generate rules for compiling multiple .c, .cpp, or .S files to individual .o files
-func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles android.Paths,
+func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles, noTidySrcs android.Paths,
 	flags builderFlags, pathDeps android.Paths, cFlagsDeps android.Paths) Objects {
 
 	// Source files are one-to-one with tidy, coverage, or kythe files, if enabled.
 	objFiles := make(android.Paths, len(srcFiles))
 	var tidyFiles android.Paths
+	noTidySrcsMap := make(map[android.Path]bool)
 	var tidyVars string
 	if flags.tidy {
 		tidyFiles = make(android.Paths, 0, len(srcFiles))
+		for _, path := range noTidySrcs {
+			noTidySrcsMap[path] = true
+		}
 		tidyTimeout := ctx.Config().Getenv("TIDY_TIMEOUT")
 		if len(tidyTimeout) > 0 {
 			tidyVars += "TIDY_TIMEOUT=" + tidyTimeout
@@ -673,7 +677,8 @@ func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles and
 			kytheFiles = append(kytheFiles, kytheFile)
 		}
 
-		if tidy {
+		//  Even with tidy, some src file could be skipped by noTidySrcsMap.
+		if tidy && !noTidySrcsMap[srcFile] {
 			tidyFile := android.ObjPathWithExt(ctx, subdir, srcFile, "tidy")
 			tidyFiles = append(tidyFiles, tidyFile)