bp2build: support generated sources and hdrs

There are two pieces to make this work:
1. Local include paths must include $(BINDIR)-relative paths, to support
generated headers in those directories.
2. The srcs that bp2build outputs for BUILD targets must include labels
for targets given in generated_hdrs and generated_srcs.

Support for exported_generated_hdrs intentionally deferred.

This allows us to remove several targets from the bp2build denylist.
Some are moved to the mixed build denylist, because genreated headers are
still unsupported in mixed builds.
Test: bp2build.sh CI script

Change-Id: Ib4f9dac20f6445487b8dad53b91eac01f437a590

cc/bp2build.go

@@ -14,10 +14,11 @@
 package cc
 
 import (
-	"android/soong/android"
-	"android/soong/bazel"
 	"path/filepath"
 	"strings"
+
+	"android/soong/android"
+	"android/soong/bazel"
 )
 
 // bp2build functions and helpers for converting cc_* modules to Bazel.
@@ -49,6 +50,22 @@ func depsBp2BuildMutator(ctx android.BottomUpMutatorContext) {
 
 	var allDeps []string
 
+	for _, p := range module.GetTargetProperties(ctx, &BaseCompilerProperties{}) {
+		// base compiler props
+		if baseCompilerProps, ok := p.(*BaseCompilerProperties); ok {
+			allDeps = append(allDeps, baseCompilerProps.Generated_headers...)
+			allDeps = append(allDeps, baseCompilerProps.Generated_sources...)
+		}
+	}
+
+	for _, p := range module.GetArchProperties(ctx, &BaseCompilerProperties{}) {
+		// arch specific compiler props
+		if baseCompilerProps, ok := p.(*BaseCompilerProperties); ok {
+			allDeps = append(allDeps, baseCompilerProps.Generated_headers...)
+			allDeps = append(allDeps, baseCompilerProps.Generated_sources...)
+		}
+	}
+
 	for _, p := range module.GetTargetProperties(ctx, &BaseLinkerProperties{}) {
 		// arch specific linker props
 		if baseLinkerProps, ok := p.(*BaseLinkerProperties); ok {
@@ -173,11 +190,19 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 	var srcs bazel.LabelListAttribute
 	var copts bazel.StringListAttribute
 
-	// Creates the -I flag for a directory, while making the directory relative
+	// Creates the -I flags for a directory, while making the directory relative
 	// to the exec root for Bazel to work.
-	includeFlag := func(dir string) string {
+	includeFlags := func(dir string) []string {
 		// filepath.Join canonicalizes the path, i.e. it takes care of . or .. elements.
-		return "-I" + filepath.Join(ctx.ModuleDir(), dir)
+		moduleDirRootedPath := filepath.Join(ctx.ModuleDir(), dir)
+		return []string{
+			"-I" + moduleDirRootedPath,
+			// Include the bindir-rooted path (using make variable substitution). This most
+			// closely matches Bazel's native include path handling, which allows for dependency
+			// on generated headers in these directories.
+			// TODO(b/188084383): Handle local include directories in Bazel.
+			"-I$(BINDIR)/" + moduleDirRootedPath,
+		}
 	}
 
 	// Parse the list of module-relative include directories (-I).
@@ -197,7 +222,7 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 			copts = append(copts, strings.Split(flag, " ")...)
 		}
 		for _, dir := range parseLocalIncludeDirs(baseCompilerProps) {
-			copts = append(copts, includeFlag(dir))
+			copts = append(copts, includeFlags(dir)...)
 		}
 		return copts
 	}
@@ -215,9 +240,17 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 	parseSrcs := func(baseCompilerProps *BaseCompilerProperties) bazel.LabelList {
 		// Combine the base srcs and arch-specific srcs
 		allSrcs := append(baseSrcs, baseCompilerProps.Srcs...)
+		// Add srcs-like dependencies such as generated files.
+		// First create a LabelList containing these dependencies, then merge the values with srcs.
+		generatedHdrsAndSrcs := baseCompilerProps.Generated_headers
+		generatedHdrsAndSrcs = append(generatedHdrsAndSrcs, baseCompilerProps.Generated_sources...)
+
+		generatedHdrsAndSrcsLabelList := android.BazelLabelForModuleDeps(ctx, generatedHdrsAndSrcs)
+
 		// Combine the base exclude_srcs and configuration-specific exclude_srcs
 		allExcludeSrcs := append(baseExcludeSrcs, baseCompilerProps.Exclude_srcs...)
-		return android.BazelLabelForModuleSrcExcludes(ctx, allSrcs, allExcludeSrcs)
+		allSrcsLabelList := android.BazelLabelForModuleSrcExcludes(ctx, allSrcs, allExcludeSrcs)
+		return bazel.AppendBazelLabelLists(allSrcsLabelList, generatedHdrsAndSrcsLabelList)
 	}
 
 	for _, props := range module.compiler.compilerProps() {
@@ -227,8 +260,8 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 
 			// Used for arch-specific srcs later.
 			baseSrcs = baseCompilerProps.Srcs
-			baseExcludeSrcs = baseCompilerProps.Exclude_srcs
 			baseSrcsLabelList = parseSrcs(baseCompilerProps)
+			baseExcludeSrcs = baseCompilerProps.Exclude_srcs
 			break
 		}
 	}
@@ -237,9 +270,9 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 	// target has access to all headers recursively in the package, and has
 	// "-I<module-dir>" in its copts.
 	if c, ok := module.compiler.(*baseCompiler); ok && c.includeBuildDirectory() {
-		copts.Value = append(copts.Value, includeFlag("."))
+		copts.Value = append(copts.Value, includeFlags(".")...)
 	} else if c, ok := module.compiler.(*libraryDecorator); ok && c.includeBuildDirectory() {
-		copts.Value = append(copts.Value, includeFlag("."))
+		copts.Value = append(copts.Value, includeFlags(".")...)
 	}
 
 	for arch, props := range module.GetArchProperties(ctx, &BaseCompilerProperties{}) {