1// Copyright 2016 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package cc
16
17import (
18	"fmt"
19
20	"android/soong/android"
21	"android/soong/bazel"
22)
23
24//
25// Objects (for crt*.o)
26//
27
28func init() {
29	android.RegisterModuleType("cc_object", ObjectFactory)
30	android.RegisterSdkMemberType(ccObjectSdkMemberType)
31
32	android.RegisterBp2BuildMutator("cc_object", ObjectBp2Build)
33}
34
35var ccObjectSdkMemberType = &librarySdkMemberType{
36	SdkMemberTypeBase: android.SdkMemberTypeBase{
37		PropertyName: "native_objects",
38		SupportsSdk:  true,
39	},
40	prebuiltModuleType: "cc_prebuilt_object",
41	linkTypes:          nil,
42}
43
44type objectLinker struct {
45	*baseLinker
46	Properties ObjectLinkerProperties
47}
48
49type objectBazelHandler struct {
50	bazelHandler
51
52	module *Module
53}
54
55func (handler *objectBazelHandler) generateBazelBuildActions(ctx android.ModuleContext, label string) bool {
56	bazelCtx := ctx.Config().BazelContext
57	objPaths, ok := bazelCtx.GetOutputFiles(label, ctx.Arch().ArchType)
58	if ok {
59		if len(objPaths) != 1 {
60			ctx.ModuleErrorf("expected exactly one object file for '%s', but got %s", label, objPaths)
61			return false
62		}
63
64		handler.module.outputFile = android.OptionalPathForPath(android.PathForBazelOut(ctx, objPaths[0]))
65	}
66	return ok
67}
68
69type ObjectLinkerProperties struct {
70	// list of modules that should only provide headers for this module.
71	Header_libs []string `android:"arch_variant,variant_prepend"`
72
73	// names of other cc_object modules to link into this module using partial linking
74	Objs []string `android:"arch_variant"`
75
76	// if set, add an extra objcopy --prefix-symbols= step
77	Prefix_symbols *string
78
79	// if set, the path to a linker script to pass to ld -r when combining multiple object files.
80	Linker_script *string `android:"path,arch_variant"`
81
82	// Indicates that this module is a CRT object. CRT objects will be split
83	// into a variant per-API level between min_sdk_version and current.
84	Crt *bool
85}
86
87func newObject() *Module {
88	module := newBaseModule(android.HostAndDeviceSupported, android.MultilibBoth)
89	module.sanitize = &sanitize{}
90	module.stl = &stl{}
91	return module
92}
93
94// cc_object runs the compiler without running the linker. It is rarely
95// necessary, but sometimes used to generate .s files from .c files to use as
96// input to a cc_genrule module.
97func ObjectFactory() android.Module {
98	module := newObject()
99	module.linker = &objectLinker{
100		baseLinker: NewBaseLinker(module.sanitize),
101	}
102	module.compiler = NewBaseCompiler()
103	module.bazelHandler = &objectBazelHandler{module: module}
104
105	// Clang's address-significance tables are incompatible with ld -r.
106	module.compiler.appendCflags([]string{"-fno-addrsig"})
107
108	module.sdkMemberTypes = []android.SdkMemberType{ccObjectSdkMemberType}
109
110	return module.Init()
111}
112
113// For bp2build conversion.
114type bazelObjectAttributes struct {
115	Srcs    bazel.LabelListAttribute
116	Hdrs    bazel.LabelListAttribute
117	Deps    bazel.LabelListAttribute
118	Copts   bazel.StringListAttribute
119	Asflags []string
120}
121
122type bazelObject struct {
123	android.BazelTargetModuleBase
124	bazelObjectAttributes
125}
126
127func (m *bazelObject) Name() string {
128	return m.BaseModuleName()
129}
130
131func (m *bazelObject) GenerateAndroidBuildActions(ctx android.ModuleContext) {}
132
133func BazelObjectFactory() android.Module {
134	module := &bazelObject{}
135	module.AddProperties(&module.bazelObjectAttributes)
136	android.InitBazelTargetModule(module)
137	return module
138}
139
140// ObjectBp2Build is the bp2build converter from cc_object modules to the
141// Bazel equivalent target, plus any necessary include deps for the cc_object.
142func ObjectBp2Build(ctx android.TopDownMutatorContext) {
143	m, ok := ctx.Module().(*Module)
144	if !ok || !m.ConvertWithBp2build(ctx) {
145		return
146	}
147
148	// a Module can be something other than a cc_object.
149	if ctx.ModuleType() != "cc_object" {
150		return
151	}
152
153	if m.compiler == nil {
154		// a cc_object must have access to the compiler decorator for its props.
155		ctx.ModuleErrorf("compiler must not be nil for a cc_object module")
156	}
157
158	// Set arch-specific configurable attributes
159	compilerAttrs := bp2BuildParseCompilerProps(ctx, m)
160	var asFlags []string
161
162	var deps bazel.LabelListAttribute
163	for _, props := range m.linker.linkerProps() {
164		if objectLinkerProps, ok := props.(*ObjectLinkerProperties); ok {
165			deps = bazel.MakeLabelListAttribute(
166				android.BazelLabelForModuleDeps(ctx, objectLinkerProps.Objs))
167		}
168	}
169
170	productVariableProps := android.ProductVariableProperties(ctx)
171	if props, exists := productVariableProps["Asflags"]; exists {
172		// TODO(b/183595873): consider deduplicating handling of product variable properties
173		for _, prop := range props {
174			flags, ok := prop.Property.([]string)
175			if !ok {
176				ctx.ModuleErrorf("Could not convert product variable asflag property")
177				return
178			}
179			// TODO(b/183595873) handle other product variable usages -- as selects?
180			if newFlags, subbed := bazel.TryVariableSubstitutions(flags, prop.ProductConfigVariable); subbed {
181				asFlags = append(asFlags, newFlags...)
182			}
183		}
184	}
185	// TODO(b/183595872) warn/error if we're not handling product variables
186
187	attrs := &bazelObjectAttributes{
188		Srcs:    compilerAttrs.srcs,
189		Deps:    deps,
190		Copts:   compilerAttrs.copts,
191		Asflags: asFlags,
192	}
193
194	props := bazel.BazelTargetModuleProperties{
195		Rule_class:        "cc_object",
196		Bzl_load_location: "//build/bazel/rules:cc_object.bzl",
197	}
198
199	ctx.CreateBazelTargetModule(BazelObjectFactory, m.Name(), props, attrs)
200}
201
202func (object *objectLinker) appendLdflags(flags []string) {
203	panic(fmt.Errorf("appendLdflags on objectLinker not supported"))
204}
205
206func (object *objectLinker) linkerProps() []interface{} {
207	return []interface{}{&object.Properties}
208}
209
210func (*objectLinker) linkerInit(ctx BaseModuleContext) {}
211
212func (object *objectLinker) linkerDeps(ctx DepsContext, deps Deps) Deps {
213	deps.HeaderLibs = append(deps.HeaderLibs, object.Properties.Header_libs...)
214	deps.ObjFiles = append(deps.ObjFiles, object.Properties.Objs...)
215	return deps
216}
217
218func (object *objectLinker) linkerFlags(ctx ModuleContext, flags Flags) Flags {
219	flags.Global.LdFlags = append(flags.Global.LdFlags, ctx.toolchain().ToolchainClangLdflags())
220
221	if lds := android.OptionalPathForModuleSrc(ctx, object.Properties.Linker_script); lds.Valid() {
222		flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-T,"+lds.String())
223		flags.LdFlagsDeps = append(flags.LdFlagsDeps, lds.Path())
224	}
225	return flags
226}
227
228func (object *objectLinker) link(ctx ModuleContext,
229	flags Flags, deps PathDeps, objs Objects) android.Path {
230
231	objs = objs.Append(deps.Objs)
232
233	var outputFile android.Path
234	builderFlags := flagsToBuilderFlags(flags)
235
236	if len(objs.objFiles) == 1 && String(object.Properties.Linker_script) == "" {
237		outputFile = objs.objFiles[0]
238
239		if String(object.Properties.Prefix_symbols) != "" {
240			output := android.PathForModuleOut(ctx, ctx.ModuleName()+objectExtension)
241			transformBinaryPrefixSymbols(ctx, String(object.Properties.Prefix_symbols), outputFile,
242				builderFlags, output)
243			outputFile = output
244		}
245	} else {
246		output := android.PathForModuleOut(ctx, ctx.ModuleName()+objectExtension)
247		outputFile = output
248
249		if String(object.Properties.Prefix_symbols) != "" {
250			input := android.PathForModuleOut(ctx, "unprefixed", ctx.ModuleName()+objectExtension)
251			transformBinaryPrefixSymbols(ctx, String(object.Properties.Prefix_symbols), input,
252				builderFlags, output)
253			output = input
254		}
255
256		transformObjsToObj(ctx, objs.objFiles, builderFlags, output, flags.LdFlagsDeps)
257	}
258
259	ctx.CheckbuildFile(outputFile)
260	return outputFile
261}
262
263func (object *objectLinker) unstrippedOutputFilePath() android.Path {
264	return nil
265}
266
267func (object *objectLinker) nativeCoverage() bool {
268	return true
269}
270
271func (object *objectLinker) coverageOutputFilePath() android.OptionalPath {
272	return android.OptionalPath{}
273}
274
275func (object *objectLinker) object() bool {
276	return true
277}
278
279func (object *objectLinker) isCrt() bool {
280	return Bool(object.Properties.Crt)
281}
282