Add (obj|tidy)-*_os, and (obj|tidy)-*_subset targets

* The obj-* targets only call clang or clang++ to compile
  C/C++ files, like the tidy-* targets only call clang-tidy.
* Add (obj|tidy)-dir_os and module_os-(obj|tidy) phony targets
  to include only targets of the specified OS.
* Add (obj|tidy)-dir_os_subset and module_os_subset-(obj|tidy) phony targets
  to include only a subset of that OS target group.
  * Most clang-tidy runs produce the same warnings for all variants
    of an OS. The *_subset targets reduce runs over multiple variants.
  * The obj-*subset targets are useful for a quick test to compile
    at least one variant of every C/C++ file for each OS.
* The (obj|tidy)-soong phony target is changed to include only
  (obj|tidy)-top_level_directory targets instead of ALL
  module-(obj|tidy) targets in all subdirectories.
* For aosp_arm64-eng make tidy-* targets; count NINJA commands:
    tidy-soong                     381K
    tidy-soong_subset              106K
    tidy-soong_android             294K
    tidy-soong_android_subset       73K
    tidy-soong_linux_glibc          84K
    tidy-soong_windows              12K
    tidy-bionic                     12K
    tidy-bionic_subset               2.4K
    tidy-bionic_android             11.5K
    tidy-bionic_android_subset       2.1K
    tidy-bionic_linux_glibc          1K
    tidy-device_android              7K
    tidy-device_android_subset       5K
    tidy-hardware_android            3K
    tidy-hardware_android_subset     9K
    libfec_rs-tidy                   33
    libfec_rs_subset-tidy             9
    libfec_rs_android-tidy           18
    libfec_rs_android_subset-tidy     3
* For aosp_arm64-eng make obj-* targets; count NINJA commands:
    obj-soong                      399K
    obj-soong_subset               112K
    obj-soong_android              305K
    obj-soong_android_subset        75K
    obj-soong_linux_glibc           90K
    obj-soong_linux_glibc_subset    38K
    obj-soong_windows               12K
    obj-bionic                      15K
    obj-bionic_subset                3K
    obj-bionic_android              14K
    obj-bionic_android_subset        2.3K
    obj-bionic_linux_glibc           1.3K
    obj-system-core                  6K
    obj-system-core_subset           3K
    obj-frameworks-base             16K
    obj-frameworks-base_subset       6K
    libfec_rs-obj                    33
    libfec_rs_subset-obj              9
    libfec_rs_android-obj            18
    libfec_rs_android_subset-obj      3

Test: NINJA_ARGS="-n" WITH_TIDY=1 make some_obj_tidy_target;
      compare output commands from various phony targets
Bug: 199169329
Bug: 202769240
Change-Id: I186c45dc07c5884888c1063dfc09cf212ffb0ebf

cc/builder.go

@@ -413,7 +413,7 @@ type StripFlags struct {
 // Objects is a collection of file paths corresponding to outputs for C++ related build statements.
 type Objects struct {
 	objFiles      android.Paths
-	tidyFiles     android.WritablePaths
+	tidyFiles     android.Paths
 	coverageFiles android.Paths
 	sAbiDumpFiles android.Paths
 	kytheFiles    android.Paths
@@ -422,7 +422,7 @@ type Objects struct {
 func (a Objects) Copy() Objects {
 	return Objects{
 		objFiles:      append(android.Paths{}, a.objFiles...),
-		tidyFiles:     append(android.WritablePaths{}, a.tidyFiles...),
+		tidyFiles:     append(android.Paths{}, a.tidyFiles...),
 		coverageFiles: append(android.Paths{}, a.coverageFiles...),
 		sAbiDumpFiles: append(android.Paths{}, a.sAbiDumpFiles...),
 		kytheFiles:    append(android.Paths{}, a.kytheFiles...),
@@ -451,11 +451,11 @@ func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles, no
 
 	// Source files are one-to-one with tidy, coverage, or kythe files, if enabled.
 	objFiles := make(android.Paths, len(srcFiles))
-	var tidyFiles android.WritablePaths
+	var tidyFiles android.Paths
 	noTidySrcsMap := make(map[android.Path]bool)
 	var tidyVars string
 	if flags.tidy {
-		tidyFiles = make(android.WritablePaths, 0, len(srcFiles))
+		tidyFiles = make(android.Paths, 0, len(srcFiles))
 		for _, path := range noTidySrcs {
 			noTidySrcsMap[path] = true
 		}
@@ -665,7 +665,6 @@ func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles, no
 				rule = clangTidyRE
 			}
 
-			ctx.TidyFile(tidyFile)
 			ctx.Build(pctx, android.BuildParams{
 				Rule:        rule,
 				Description: "clang-tidy " + srcFile.Rel(),
@@ -719,7 +718,7 @@ func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles, no
 // Generate a rule for compiling multiple .o files to a static library (.a)
 func transformObjToStaticLib(ctx android.ModuleContext,
 	objFiles android.Paths, wholeStaticLibs android.Paths,
-	flags builderFlags, outputFile android.ModuleOutPath, deps android.Paths, validations android.WritablePaths) {
+	flags builderFlags, outputFile android.ModuleOutPath, deps android.Paths, validations android.Paths) {
 
 	arCmd := "${config.ClangBin}/llvm-ar"
 	arFlags := ""
@@ -734,7 +733,7 @@ func transformObjToStaticLib(ctx android.ModuleContext,
 			Output:      outputFile,
 			Inputs:      objFiles,
 			Implicits:   deps,
-			Validations: validations.Paths(),
+			Validations: validations,
 			Args: map[string]string{
 				"arFlags": "crsPD" + arFlags,
 				"arCmd":   arCmd,
@@ -764,7 +763,7 @@ func transformObjToStaticLib(ctx android.ModuleContext,
 func transformObjToDynamicBinary(ctx android.ModuleContext,
 	objFiles, sharedLibs, staticLibs, lateStaticLibs, wholeStaticLibs, deps, crtBegin, crtEnd android.Paths,
 	groupLate bool, flags builderFlags, outputFile android.WritablePath,
-	implicitOutputs android.WritablePaths, validations android.WritablePaths) {
+	implicitOutputs android.WritablePaths, validations android.Paths) {
 
 	ldCmd := "${config.ClangBin}/clang++"
 
@@ -831,7 +830,7 @@ func transformObjToDynamicBinary(ctx android.ModuleContext,
 		Inputs:          objFiles,
 		Implicits:       deps,
 		OrderOnly:       sharedLibs,
-		Validations:     validations.Paths(),
+		Validations:     validations,
 		Args:            args,
 	})
 }