bp2build: arch-specific exclude_srcs and srcs.

OS-specific exclude_srcs and srcs will be done in a follow-up, due to
complexities from merging multiple select statements together.

Test: TH
Bug: 186153868
Change-Id: I01b881e9a5a7cd41b4a507f8be7e9e65eab37bdc

android/bazel.go

@@ -220,8 +220,7 @@ var (
 	// Per-module denylist to opt modules out of mixed builds. Such modules will
 	// still be generated via bp2build.
 	mixedBuildsDisabledList = []string{
-		"libc_gdtoa",   // ruperts@, cc_library_static, OK for bp2build but undefined symbol: __strtorQ for mixed builds
+		"libc_gdtoa", // ruperts@, cc_library_static, OK for bp2build but undefined symbol: __strtorQ for mixed builds
-		"libc_openbsd", // ruperts@, cc_library_static, OK for bp2build but error: duplicate symbol: strcpy for mixed builds
 	}
 
 	// Used for quicker lookups

bazel/properties.go

@@ -183,6 +183,15 @@ const (
 	OS_LINUX        = "linux_glibc"
 	OS_LINUX_BIONIC = "linux_bionic"
 	OS_WINDOWS      = "windows"
+
+	// This is the string representation of the default condition wherever a
+	// configurable attribute is used in a select statement, i.e.
+	// //conditions:default for Bazel.
+	//
+	// This is consistently named "conditions_default" to mirror the Soong
+	// config variable default key in an Android.bp file, although there's no
+	// integration with Soong config variables (yet).
+	CONDITIONS_DEFAULT = "conditions_default"
 )
 
 var (
@@ -194,21 +203,23 @@ var (
 	// A map of architectures to the Bazel label of the constraint_value
 	// for the @platforms//cpu:cpu constraint_setting
 	PlatformArchMap = map[string]string{
-		ARCH_ARM:    "//build/bazel/platforms/arch:arm",
+		ARCH_ARM:           "//build/bazel/platforms/arch:arm",
-		ARCH_ARM64:  "//build/bazel/platforms/arch:arm64",
+		ARCH_ARM64:         "//build/bazel/platforms/arch:arm64",
-		ARCH_X86:    "//build/bazel/platforms/arch:x86",
+		ARCH_X86:           "//build/bazel/platforms/arch:x86",
-		ARCH_X86_64: "//build/bazel/platforms/arch:x86_64",
+		ARCH_X86_64:        "//build/bazel/platforms/arch:x86_64",
+		CONDITIONS_DEFAULT: "//conditions:default", // The default condition of as arch select map.
 	}
 
 	// A map of target operating systems to the Bazel label of the
 	// constraint_value for the @platforms//os:os constraint_setting
 	PlatformOsMap = map[string]string{
-		OS_ANDROID:      "//build/bazel/platforms/os:android",
+		OS_ANDROID:         "//build/bazel/platforms/os:android",
-		OS_DARWIN:       "//build/bazel/platforms/os:darwin",
+		OS_DARWIN:          "//build/bazel/platforms/os:darwin",
-		OS_FUCHSIA:      "//build/bazel/platforms/os:fuchsia",
+		OS_FUCHSIA:         "//build/bazel/platforms/os:fuchsia",
-		OS_LINUX:        "//build/bazel/platforms/os:linux",
+		OS_LINUX:           "//build/bazel/platforms/os:linux",
-		OS_LINUX_BIONIC: "//build/bazel/platforms/os:linux_bionic",
+		OS_LINUX_BIONIC:    "//build/bazel/platforms/os:linux_bionic",
-		OS_WINDOWS:      "//build/bazel/platforms/os:windows",
+		OS_WINDOWS:         "//build/bazel/platforms/os:windows",
+		CONDITIONS_DEFAULT: "//conditions:default", // The default condition of an os select map.
 	}
 )
 
@@ -224,6 +235,8 @@ type labelListArchValues struct {
 	Arm    LabelList
 	Arm64  LabelList
 	Common LabelList
+
+	ConditionsDefault LabelList
 }
 
 type labelListOsValues struct {
@@ -233,6 +246,8 @@ type labelListOsValues struct {
 	Linux       LabelList
 	LinuxBionic LabelList
 	Windows     LabelList
+
+	ConditionsDefault LabelList
 }
 
 // LabelListAttribute is used to represent a list of Bazel labels as an
@@ -296,10 +311,11 @@ func (attrs LabelListAttribute) HasConfigurableValues() bool {
 
 func (attrs *LabelListAttribute) archValuePtrs() map[string]*LabelList {
 	return map[string]*LabelList{
-		ARCH_X86:    &attrs.ArchValues.X86,
+		ARCH_X86:           &attrs.ArchValues.X86,
-		ARCH_X86_64: &attrs.ArchValues.X86_64,
+		ARCH_X86_64:        &attrs.ArchValues.X86_64,
-		ARCH_ARM:    &attrs.ArchValues.Arm,
+		ARCH_ARM:           &attrs.ArchValues.Arm,
-		ARCH_ARM64:  &attrs.ArchValues.Arm64,
+		ARCH_ARM64:         &attrs.ArchValues.Arm64,
+		CONDITIONS_DEFAULT: &attrs.ArchValues.ConditionsDefault,
 	}
 }
 
@@ -323,12 +339,13 @@ func (attrs *LabelListAttribute) SetValueForArch(arch string, value LabelList) {
 
 func (attrs *LabelListAttribute) osValuePtrs() map[string]*LabelList {
 	return map[string]*LabelList{
-		OS_ANDROID:      &attrs.OsValues.Android,
+		OS_ANDROID:         &attrs.OsValues.Android,
-		OS_DARWIN:       &attrs.OsValues.Darwin,
+		OS_DARWIN:          &attrs.OsValues.Darwin,
-		OS_FUCHSIA:      &attrs.OsValues.Fuchsia,
+		OS_FUCHSIA:         &attrs.OsValues.Fuchsia,
-		OS_LINUX:        &attrs.OsValues.Linux,
+		OS_LINUX:           &attrs.OsValues.Linux,
-		OS_LINUX_BIONIC: &attrs.OsValues.LinuxBionic,
+		OS_LINUX_BIONIC:    &attrs.OsValues.LinuxBionic,
-		OS_WINDOWS:      &attrs.OsValues.Windows,
+		OS_WINDOWS:         &attrs.OsValues.Windows,
+		CONDITIONS_DEFAULT: &attrs.OsValues.ConditionsDefault,
 	}
 }
 
@@ -381,6 +398,8 @@ type stringListArchValues struct {
 	Arm    []string
 	Arm64  []string
 	Common []string
+
+	ConditionsDefault []string
 }
 
 type stringListOsValues struct {
@@ -390,6 +409,8 @@ type stringListOsValues struct {
 	Linux       []string
 	LinuxBionic []string
 	Windows     []string
+
+	ConditionsDefault []string
 }
 
 // HasConfigurableValues returns true if the attribute contains
@@ -411,10 +432,11 @@ func (attrs StringListAttribute) HasConfigurableValues() bool {
 
 func (attrs *StringListAttribute) archValuePtrs() map[string]*[]string {
 	return map[string]*[]string{
-		ARCH_X86:    &attrs.ArchValues.X86,
+		ARCH_X86:           &attrs.ArchValues.X86,
-		ARCH_X86_64: &attrs.ArchValues.X86_64,
+		ARCH_X86_64:        &attrs.ArchValues.X86_64,
-		ARCH_ARM:    &attrs.ArchValues.Arm,
+		ARCH_ARM:           &attrs.ArchValues.Arm,
-		ARCH_ARM64:  &attrs.ArchValues.Arm64,
+		ARCH_ARM64:         &attrs.ArchValues.Arm64,
+		CONDITIONS_DEFAULT: &attrs.ArchValues.ConditionsDefault,
 	}
 }
 
@@ -438,12 +460,13 @@ func (attrs *StringListAttribute) SetValueForArch(arch string, value []string) {
 
 func (attrs *StringListAttribute) osValuePtrs() map[string]*[]string {
 	return map[string]*[]string{
-		OS_ANDROID:      &attrs.OsValues.Android,
+		OS_ANDROID:         &attrs.OsValues.Android,
-		OS_DARWIN:       &attrs.OsValues.Darwin,
+		OS_DARWIN:          &attrs.OsValues.Darwin,
-		OS_FUCHSIA:      &attrs.OsValues.Fuchsia,
+		OS_FUCHSIA:         &attrs.OsValues.Fuchsia,
-		OS_LINUX:        &attrs.OsValues.Linux,
+		OS_LINUX:           &attrs.OsValues.Linux,
-		OS_LINUX_BIONIC: &attrs.OsValues.LinuxBionic,
+		OS_LINUX_BIONIC:    &attrs.OsValues.LinuxBionic,
-		OS_WINDOWS:      &attrs.OsValues.Windows,
+		OS_WINDOWS:         &attrs.OsValues.Windows,
+		CONDITIONS_DEFAULT: &attrs.OsValues.ConditionsDefault,
 	}
 }
 

bp2build/cc_library_static_conversion_test.go

@@ -524,6 +524,201 @@ cc_library_static {
     name = "static_dep4",
     copts = ["-I."],
     linkstatic = True,
+)`},
+		},
+		{
+			description:                        "cc_library_static simple exclude_srcs",
+			moduleTypeUnderTest:                "cc_library_static",
+			moduleTypeUnderTestFactory:         cc.LibraryStaticFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryStaticBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem: map[string]string{
+				"common.c":       "",
+				"foo-a.c":        "",
+				"foo-excluded.c": "",
+			},
+			bp: soongCcLibraryStaticPreamble + `
+cc_library_static {
+    name: "foo_static",
+    srcs: ["common.c", "foo-*.c"],
+    exclude_srcs: ["foo-excluded.c"],
+}`,
+			expectedBazelTargets: []string{`cc_library_static(
+    name = "foo_static",
+    copts = ["-I."],
+    linkstatic = True,
+    srcs = [
+        "common.c",
+        "foo-a.c",
+    ],
+)`},
+		},
+		{
+			description:                        "cc_library_static one arch specific srcs",
+			moduleTypeUnderTest:                "cc_library_static",
+			moduleTypeUnderTestFactory:         cc.LibraryStaticFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryStaticBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem: map[string]string{
+				"common.c":  "",
+				"foo-arm.c": "",
+			},
+			bp: soongCcLibraryStaticPreamble + `
+cc_library_static {
+    name: "foo_static",
+    srcs: ["common.c"],
+    arch: { arm: { srcs: ["foo-arm.c"] } }
+}`,
+			expectedBazelTargets: []string{`cc_library_static(
+    name = "foo_static",
+    copts = ["-I."],
+    linkstatic = True,
+    srcs = ["common.c"] + select({
+        "//build/bazel/platforms/arch:arm": ["foo-arm.c"],
+        "//conditions:default": [],
+    }),
+)`},
+		},
+		{
+			description:                        "cc_library_static one arch specific srcs and exclude_srcs",
+			moduleTypeUnderTest:                "cc_library_static",
+			moduleTypeUnderTestFactory:         cc.LibraryStaticFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryStaticBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem: map[string]string{
+				"common.c":           "",
+				"for-arm.c":          "",
+				"not-for-arm.c":      "",
+				"not-for-anything.c": "",
+			},
+			bp: soongCcLibraryStaticPreamble + `
+cc_library_static {
+    name: "foo_static",
+    srcs: ["common.c", "not-for-*.c"],
+    exclude_srcs: ["not-for-anything.c"],
+    arch: {
+        arm: { srcs: ["for-arm.c"], exclude_srcs: ["not-for-arm.c"] },
+    },
+}`,
+			expectedBazelTargets: []string{`cc_library_static(
+    name = "foo_static",
+    copts = ["-I."],
+    linkstatic = True,
+    srcs = ["common.c"] + select({
+        "//build/bazel/platforms/arch:arm": ["for-arm.c"],
+        "//conditions:default": ["not-for-arm.c"],
+    }),
+)`},
+		},
+		{
+			description:                        "cc_library_static arch specific exclude_srcs for 2 architectures",
+			moduleTypeUnderTest:                "cc_library_static",
+			moduleTypeUnderTestFactory:         cc.LibraryStaticFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryStaticBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem: map[string]string{
+				"common.c":      "",
+				"for-arm.c":     "",
+				"for-x86.c":     "",
+				"not-for-arm.c": "",
+				"not-for-x86.c": "",
+			},
+			bp: soongCcLibraryStaticPreamble + `
+cc_library_static {
+    name: "foo_static",
+    srcs: ["common.c", "not-for-*.c"],
+    exclude_srcs: ["not-for-everything.c"],
+    arch: {
+        arm: { srcs: ["for-arm.c"], exclude_srcs: ["not-for-arm.c"] },
+        x86: { srcs: ["for-x86.c"], exclude_srcs: ["not-for-x86.c"] },
+    },
+} `,
+			expectedBazelTargets: []string{`cc_library_static(
+    name = "foo_static",
+    copts = ["-I."],
+    linkstatic = True,
+    srcs = ["common.c"] + select({
+        "//build/bazel/platforms/arch:arm": [
+            "for-arm.c",
+            "not-for-x86.c",
+        ],
+        "//build/bazel/platforms/arch:x86": [
+            "for-x86.c",
+            "not-for-arm.c",
+        ],
+        "//conditions:default": [
+            "not-for-arm.c",
+            "not-for-x86.c",
+        ],
+    }),
+)`},
+		},
+		{
+			description:                        "cc_library_static arch specific exclude_srcs for 4 architectures",
+			moduleTypeUnderTest:                "cc_library_static",
+			moduleTypeUnderTestFactory:         cc.LibraryStaticFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryStaticBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem: map[string]string{
+				"common.c":             "",
+				"for-arm.c":            "",
+				"for-arm64.c":          "",
+				"for-x86.c":            "",
+				"for-x86_64.c":         "",
+				"not-for-arm.c":        "",
+				"not-for-arm64.c":      "",
+				"not-for-x86.c":        "",
+				"not-for-x86_64.c":     "",
+				"not-for-everything.c": "",
+			},
+			bp: soongCcLibraryStaticPreamble + `
+cc_library_static {
+    name: "foo_static",
+    srcs: ["common.c", "not-for-*.c"],
+    exclude_srcs: ["not-for-everything.c"],
+    arch: {
+        arm: { srcs: ["for-arm.c"], exclude_srcs: ["not-for-arm.c"] },
+        arm64: { srcs: ["for-arm64.c"], exclude_srcs: ["not-for-arm64.c"] },
+        x86: { srcs: ["for-x86.c"], exclude_srcs: ["not-for-x86.c"] },
+        x86_64: { srcs: ["for-x86_64.c"], exclude_srcs: ["not-for-x86_64.c"] },
+	},
+} `,
+			expectedBazelTargets: []string{`cc_library_static(
+    name = "foo_static",
+    copts = ["-I."],
+    linkstatic = True,
+    srcs = ["common.c"] + select({
+        "//build/bazel/platforms/arch:arm": [
+            "for-arm.c",
+            "not-for-arm64.c",
+            "not-for-x86.c",
+            "not-for-x86_64.c",
+        ],
+        "//build/bazel/platforms/arch:arm64": [
+            "for-arm64.c",
+            "not-for-arm.c",
+            "not-for-x86.c",
+            "not-for-x86_64.c",
+        ],
+        "//build/bazel/platforms/arch:x86": [
+            "for-x86.c",
+            "not-for-arm.c",
+            "not-for-arm64.c",
+            "not-for-x86_64.c",
+        ],
+        "//build/bazel/platforms/arch:x86_64": [
+            "for-x86_64.c",
+            "not-for-arm.c",
+            "not-for-arm64.c",
+            "not-for-x86.c",
+        ],
+        "//conditions:default": [
+            "not-for-arm.c",
+            "not-for-arm64.c",
+            "not-for-x86.c",
+            "not-for-x86_64.c",
+        ],
+    }),
 )`},
 		},
 	}

bp2build/configurability.go

@@ -99,8 +99,15 @@ func prettyPrintSelectMap(selectMap map[string]reflect.Value, defaultValue strin
 		return "", nil
 	}
 
+	// addConditionsDefault := false
+	conditionsDefaultKey := bazel.PlatformArchMap[bazel.CONDITIONS_DEFAULT]
+
 	var selects string
 	for _, selectKey := range android.SortedStringKeys(selectMap) {
+		if selectKey == conditionsDefaultKey {
+			// Handle default condition later.
+			continue
+		}
 		value := selectMap[selectKey]
 		if isZero(value) {
 			// Ignore zero values to not generate empty lists.
@@ -125,8 +132,22 @@ func prettyPrintSelectMap(selectMap map[string]reflect.Value, defaultValue strin
 	// Create the map.
 	ret := "select({\n"
 	ret += selects
-	// default condition comes last.
+
-	ret += fmt.Sprintf("%s\"%s\": %s,\n", makeIndent(indent+1), "//conditions:default", defaultValue)
+	// Handle the default condition
+	s, err := prettyPrintSelectEntry(selectMap[conditionsDefaultKey], conditionsDefaultKey, indent)
+	if err != nil {
+		return "", err
+	}
+	if s == "" {
+		// Print an explicit empty list (the default value) even if the value is
+		// empty, to avoid errors about not finding a configuration that matches.
+		ret += fmt.Sprintf("%s\"%s\": %s,\n", makeIndent(indent+1), "//conditions:default", defaultValue)
+	} else {
+		// Print the custom default value.
+		ret += s
+		ret += ",\n"
+	}
+
 	ret += makeIndent(indent)
 	ret += "})"
 

cc/bp2build.go

@@ -90,11 +90,6 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 		return "-I" + filepath.Join(ctx.ModuleDir(), dir)
 	}
 
-	// Parse the list of srcs, excluding files from exclude_srcs.
-	parseSrcs := func(baseCompilerProps *BaseCompilerProperties) bazel.LabelList {
-		return android.BazelLabelForModuleSrcExcludes(ctx, baseCompilerProps.Srcs, baseCompilerProps.Exclude_srcs)
-	}
-
 	// Parse the list of module-relative include directories (-I).
 	parseLocalIncludeDirs := func(baseCompilerProps *BaseCompilerProperties) []string {
 		// include_dirs are root-relative, not module-relative.
@@ -111,14 +106,40 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 		return copts
 	}
 
+	// baseSrcs contain the list of src files that are used for every configuration.
+	var baseSrcs []string
+	// baseExcludeSrcs contain the list of src files that are excluded for every configuration.
+	var baseExcludeSrcs []string
+	// baseSrcsLabelList is a clone of the base srcs LabelList, used for computing the
+	// arch or os specific srcs later.
+	var baseSrcsLabelList bazel.LabelList
+
+	// Parse srcs from an arch or OS's props value, taking the base srcs and
+	// exclude srcs into account.
+	parseSrcs := func(baseCompilerProps *BaseCompilerProperties) bazel.LabelList {
+		// Combine the base srcs and arch-specific srcs
+		allSrcs := append(baseSrcs, baseCompilerProps.Srcs...)
+		// Combine the base exclude_srcs and configuration-specific exclude_srcs
+		allExcludeSrcs := append(baseExcludeSrcs, baseCompilerProps.Exclude_srcs...)
+		return android.BazelLabelForModuleSrcExcludes(ctx, allSrcs, allExcludeSrcs)
+	}
+
 	for _, props := range module.compiler.compilerProps() {
 		if baseCompilerProps, ok := props.(*BaseCompilerProperties); ok {
 			srcs.Value = parseSrcs(baseCompilerProps)
 			copts.Value = parseCopts(baseCompilerProps)
+
+			// Used for arch-specific srcs later.
+			baseSrcs = baseCompilerProps.Srcs
+			baseExcludeSrcs = baseCompilerProps.Exclude_srcs
+			baseSrcsLabelList = parseSrcs(baseCompilerProps)
 			break
 		}
 	}
 
+	// Handle include_build_directory prop. If the property is true, then the
+	// 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("."))
 	} else if c, ok := module.compiler.(*libraryDecorator); ok && c.includeBuildDirectory() {
@@ -127,16 +148,40 @@ func bp2BuildParseCompilerProps(ctx android.TopDownMutatorContext, module *Modul
 
 	for arch, props := range module.GetArchProperties(&BaseCompilerProperties{}) {
 		if baseCompilerProps, ok := props.(*BaseCompilerProperties); ok {
-			srcsList := parseSrcs(baseCompilerProps)
+			// If there's arch specific srcs or exclude_srcs, generate a select entry for it.
-			srcs.SetValueForArch(arch.Name, bazel.SubtractBazelLabelList(srcsList, srcs.Value))
+			// TODO(b/186153868): do this for OS specific srcs and exclude_srcs too.
+			if len(baseCompilerProps.Srcs) > 0 || len(baseCompilerProps.Exclude_srcs) > 0 {
+				srcsList := parseSrcs(baseCompilerProps)
+				srcs.SetValueForArch(arch.Name, srcsList)
+				// The base srcs value should not contain any arch-specific excludes.
+				srcs.Value = bazel.SubtractBazelLabelList(srcs.Value, bazel.LabelList{Includes: srcsList.Excludes})
+			}
+
 			copts.SetValueForArch(arch.Name, parseCopts(baseCompilerProps))
 		}
 	}
 
+	// After going through all archs, delete the duplicate files in the arch
+	// values that are already in the base srcs.Value.
+	for arch, props := range module.GetArchProperties(&BaseCompilerProperties{}) {
+		if _, ok := props.(*BaseCompilerProperties); ok {
+			srcs.SetValueForArch(arch.Name, bazel.SubtractBazelLabelList(srcs.GetValueForArch(arch.Name), srcs.Value))
+		}
+	}
+
+	// Now that the srcs.Value list is finalized, compare it with the original
+	// list, and put the difference into the default condition for the arch
+	// select.
+	defaultsSrcs := bazel.SubtractBazelLabelList(baseSrcsLabelList, srcs.Value)
+	// TODO(b/186153868): handle the case with multiple variant types, e.g. when arch and os are both used.
+	srcs.SetValueForArch(bazel.CONDITIONS_DEFAULT, defaultsSrcs)
+
+	// Handle OS specific props.
 	for os, props := range module.GetTargetProperties(&BaseCompilerProperties{}) {
 		if baseCompilerProps, ok := props.(*BaseCompilerProperties); ok {
 			srcsList := parseSrcs(baseCompilerProps)
-			srcs.SetValueForOS(os.Name, bazel.SubtractBazelLabelList(srcsList, srcs.Value))
+			// TODO(b/186153868): add support for os-specific srcs and exclude_srcs
+			srcs.SetValueForOS(os.Name, bazel.SubtractBazelLabelList(srcsList, baseSrcsLabelList))
 			copts.SetValueForOS(os.Name, parseCopts(baseCompilerProps))
 		}
 	}