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-rw-r--r--startop/view_compiler/Android.bp10
-rw-r--r--startop/view_compiler/TEST_MAPPING7
-rw-r--r--startop/view_compiler/dex_builder.cc193
-rw-r--r--startop/view_compiler/dex_builder.h171
-rw-r--r--startop/view_compiler/dex_builder_test.cc60
5 files changed, 390 insertions, 51 deletions
diff --git a/startop/view_compiler/Android.bp b/startop/view_compiler/Android.bp
index 3681529643bc..c39688cb8f2d 100644
--- a/startop/view_compiler/Android.bp
+++ b/startop/view_compiler/Android.bp
@@ -16,10 +16,15 @@
cc_defaults {
name: "viewcompiler_defaults",
+ header_libs: [
+ "libbase_headers",
+ ],
shared_libs: [
+ "libbase",
"libdexfile",
"slicer",
],
+ cppflags: ["-std=c++17"],
}
cc_library_host_static {
@@ -30,9 +35,6 @@ cc_library_host_static {
"java_lang_builder.cc",
"util.cc",
],
- static_libs: [
- "libbase",
- ],
}
cc_binary_host {
@@ -42,7 +44,6 @@ cc_binary_host {
"main.cc",
],
static_libs: [
- "libbase",
"libtinyxml2",
"libgflags",
"libviewcompiler",
@@ -59,4 +60,5 @@ cc_test_host {
static_libs: [
"libviewcompiler",
],
+ test_suites: ["general-tests"],
}
diff --git a/startop/view_compiler/TEST_MAPPING b/startop/view_compiler/TEST_MAPPING
deleted file mode 100644
index cc4b17a7a65a..000000000000
--- a/startop/view_compiler/TEST_MAPPING
+++ /dev/null
@@ -1,7 +0,0 @@
-{
- "presubmit": [
- {
- "name": "view-compiler-tests"
- }
- ]
-}
diff --git a/startop/view_compiler/dex_builder.cc b/startop/view_compiler/dex_builder.cc
index 7a9f41fd8f38..13e7f73e6713 100644
--- a/startop/view_compiler/dex_builder.cc
+++ b/startop/view_compiler/dex_builder.cc
@@ -22,14 +22,16 @@
#include <fstream>
#include <memory>
+#define DCHECK_NOT_NULL(p) DCHECK((p) != nullptr)
+
namespace startop {
namespace dex {
using std::shared_ptr;
using std::string;
-using art::Instruction;
using ::dex::kAccPublic;
+using Op = Instruction::Op;
const TypeDescriptor TypeDescriptor::Int() { return TypeDescriptor{"I"}; };
const TypeDescriptor TypeDescriptor::Void() { return TypeDescriptor{"V"}; };
@@ -43,6 +45,20 @@ constexpr size_t kMaxEncodedStringLength{5};
} // namespace
+std::ostream& operator<<(std::ostream& out, const Instruction::Op& opcode) {
+ switch (opcode) {
+ case Instruction::Op::kReturn:
+ out << "kReturn";
+ return out;
+ case Instruction::Op::kMove:
+ out << "kMove";
+ return out;
+ case Instruction::Op::kInvokeVirtual:
+ out << "kInvokeVirtual";
+ return out;
+ }
+}
+
void* TrackingAllocator::Allocate(size_t size) {
std::unique_ptr<uint8_t[]> buffer = std::make_unique<uint8_t[]>(size);
void* raw_buffer = buffer.get();
@@ -56,7 +72,7 @@ void TrackingAllocator::Free(void* ptr) { allocations_.erase(allocations_.find(p
//
// package dextest;
// public class DexTest {
-// public static int foo() { return 5; }
+// public static int foo(String s) { return s.length(); }
// }
void WriteTestDexFile(const string& filename) {
DexBuilder dex_file;
@@ -64,11 +80,17 @@ void WriteTestDexFile(const string& filename) {
ClassBuilder cbuilder{dex_file.MakeClass("dextest.DexTest")};
cbuilder.set_source_file("dextest.java");
- MethodBuilder method{cbuilder.CreateMethod("foo", Prototype{TypeDescriptor::Int()})};
+ TypeDescriptor string_type = TypeDescriptor::FromClassname("java.lang.String");
+
+ MethodBuilder method{cbuilder.CreateMethod("foo", Prototype{TypeDescriptor::Int(), string_type})};
+
+ Value result = method.MakeRegister();
- MethodBuilder::Register r = method.MakeRegister();
- method.BuildConst4(r, 5);
- method.BuildReturn(r);
+ MethodDeclData string_length =
+ dex_file.GetOrDeclareMethod(string_type, "length", Prototype{TypeDescriptor::Int()});
+
+ method.AddInstruction(Instruction::InvokeVirtual(string_length.id, result, Value::Parameter(0)));
+ method.BuildReturn(result);
method.Encode();
@@ -78,6 +100,10 @@ void WriteTestDexFile(const string& filename) {
out_file.write(image.ptr<const char>(), image.size());
}
+TypeDescriptor TypeDescriptor::FromClassname(const std::string& name) {
+ return TypeDescriptor{art::DotToDescriptor(name.c_str())};
+}
+
DexBuilder::DexBuilder() : dex_file_{std::make_shared<ir::DexFile>()} {
dex_file_->magic = slicer::MemView{kDexFileMagic, sizeof(kDexFileMagic)};
}
@@ -119,10 +145,9 @@ ClassBuilder DexBuilder::MakeClass(const std::string& name) {
class_def->type = type_def;
class_def->super_class = GetOrAddType(art::DotToDescriptor("java.lang.Object"));
class_def->access_flags = kAccPublic;
- return ClassBuilder{this, class_def};
+ return ClassBuilder{this, name, class_def};
}
-// TODO(eholk): we probably want GetOrAddString() also
ir::Type* DexBuilder::GetOrAddType(const std::string& descriptor) {
if (types_by_descriptor_.find(descriptor) != types_by_descriptor_.end()) {
return types_by_descriptor_[descriptor];
@@ -158,16 +183,11 @@ std::string Prototype::Shorty() const {
return shorty;
}
-ClassBuilder::ClassBuilder(DexBuilder* parent, ir::Class* class_def)
- : parent_(parent), class_(class_def) {}
+ClassBuilder::ClassBuilder(DexBuilder* parent, const std::string& name, ir::Class* class_def)
+ : parent_(parent), type_descriptor_{TypeDescriptor::FromClassname(name)}, class_(class_def) {}
MethodBuilder ClassBuilder::CreateMethod(const std::string& name, Prototype prototype) {
- ir::String* dex_name{parent_->GetOrAddString(name)};
-
- auto* decl = parent_->Alloc<ir::MethodDecl>();
- decl->name = dex_name;
- decl->parent = class_->type;
- decl->prototype = prototype.Encode(parent_);
+ ir::MethodDecl* decl = parent_->GetOrDeclareMethod(type_descriptor_, name, prototype).decl;
return MethodBuilder{parent_, class_, decl};
}
@@ -187,8 +207,13 @@ ir::EncodedMethod* MethodBuilder::Encode() {
method->access_flags = kAccPublic | ::dex::kAccStatic;
auto* code = dex_->Alloc<ir::Code>();
- code->registers = num_registers_;
- // TODO: support ins and outs
+ DCHECK_NOT_NULL(decl_->prototype);
+ size_t const num_args =
+ decl_->prototype->param_types != nullptr ? decl_->prototype->param_types->types.size() : 0;
+ code->registers = num_registers_ + num_args;
+ code->ins_count = num_args;
+ code->outs_count = decl_->prototype->return_type == dex_->GetOrAddType("V") ? 0 : 1;
+ EncodeInstructions();
code->instructions = slicer::ArrayView<const ::dex::u2>(buffer_.data(), buffer_.size());
method->code = code;
@@ -197,17 +222,135 @@ ir::EncodedMethod* MethodBuilder::Encode() {
return method;
}
-MethodBuilder::Register MethodBuilder::MakeRegister() { return num_registers_++; }
+Value MethodBuilder::MakeRegister() { return Value::Local(num_registers_++); }
+
+void MethodBuilder::AddInstruction(Instruction instruction) {
+ instructions_.push_back(instruction);
+}
-void MethodBuilder::BuildReturn() { buffer_.push_back(Instruction::RETURN_VOID); }
+void MethodBuilder::BuildReturn() { AddInstruction(Instruction::OpNoArgs(Op::kReturn)); }
-void MethodBuilder::BuildReturn(Register src) { buffer_.push_back(Instruction::RETURN | src << 8); }
+void MethodBuilder::BuildReturn(Value src) {
+ AddInstruction(Instruction::OpWithArgs(Op::kReturn, /*destination=*/{}, src));
+}
-void MethodBuilder::BuildConst4(Register target, int value) {
+void MethodBuilder::BuildConst4(Value target, int value) {
DCHECK_LT(value, 16);
- // TODO: support more registers
- DCHECK_LT(target, 16);
- buffer_.push_back(Instruction::CONST_4 | (value << 12) | (target << 8));
+ AddInstruction(Instruction::OpWithArgs(Op::kMove, target, Value::Immediate(value)));
+}
+
+void MethodBuilder::EncodeInstructions() {
+ buffer_.clear();
+ for (const auto& instruction : instructions_) {
+ EncodeInstruction(instruction);
+ }
+}
+
+void MethodBuilder::EncodeInstruction(const Instruction& instruction) {
+ switch (instruction.opcode()) {
+ case Instruction::Op::kReturn:
+ return EncodeReturn(instruction);
+ case Instruction::Op::kMove:
+ return EncodeMove(instruction);
+ case Instruction::Op::kInvokeVirtual:
+ return EncodeInvokeVirtual(instruction);
+ }
+}
+
+void MethodBuilder::EncodeReturn(const Instruction& instruction) {
+ DCHECK_EQ(Instruction::Op::kReturn, instruction.opcode());
+ DCHECK(!instruction.dest().has_value());
+ if (instruction.args().size() == 0) {
+ buffer_.push_back(art::Instruction::RETURN_VOID);
+ } else {
+ DCHECK(instruction.args().size() == 1);
+ size_t source = RegisterValue(instruction.args()[0]);
+ buffer_.push_back(art::Instruction::RETURN | source << 8);
+ }
+}
+
+void MethodBuilder::EncodeMove(const Instruction& instruction) {
+ DCHECK_EQ(Instruction::Op::kMove, instruction.opcode());
+ DCHECK(instruction.dest().has_value());
+ DCHECK(instruction.dest()->is_register() || instruction.dest()->is_parameter());
+ DCHECK_EQ(1, instruction.args().size());
+
+ const Value& source = instruction.args()[0];
+
+ if (source.is_immediate()) {
+ // TODO: support more registers
+ DCHECK_LT(RegisterValue(*instruction.dest()), 16);
+ DCHECK_LT(source.value(), 16);
+ buffer_.push_back(art::Instruction::CONST_4 | (source.value() << 12) |
+ (RegisterValue(*instruction.dest()) << 8));
+ } else {
+ UNIMPLEMENTED(FATAL);
+ }
+}
+
+void MethodBuilder::EncodeInvokeVirtual(const Instruction& instruction) {
+ DCHECK_EQ(Instruction::Op::kInvokeVirtual, instruction.opcode());
+
+ // TODO: support more than one argument (i.e. the this argument) and change this to DCHECK_GE
+ DCHECK_EQ(1, instruction.args().size());
+
+ const Value& this_arg = instruction.args()[0];
+
+ size_t real_reg = RegisterValue(this_arg) & 0xf;
+ buffer_.push_back(1 << 12 | art::Instruction::INVOKE_VIRTUAL);
+ buffer_.push_back(instruction.method_id());
+ buffer_.push_back(real_reg);
+
+ if (instruction.dest().has_value()) {
+ real_reg = RegisterValue(*instruction.dest());
+ buffer_.push_back(real_reg << 8 | art::Instruction::MOVE_RESULT);
+ }
+}
+
+size_t MethodBuilder::RegisterValue(Value value) const {
+ if (value.is_register()) {
+ return value.value();
+ } else if (value.is_parameter()) {
+ return value.value() + num_registers_;
+ }
+ DCHECK(false && "Must be either a parameter or a register");
+ return 0;
+}
+
+const MethodDeclData& DexBuilder::GetOrDeclareMethod(TypeDescriptor type, const std::string& name,
+ Prototype prototype) {
+ MethodDeclData& entry = method_id_map_[{type, name, prototype}];
+
+ if (entry.decl == nullptr) {
+ // This method has not already been declared, so declare it.
+ ir::MethodDecl* decl = dex_file_->Alloc<ir::MethodDecl>();
+ // The method id is the last added method.
+ size_t id = dex_file_->methods.size() - 1;
+
+ ir::String* dex_name{GetOrAddString(name)};
+ decl->name = dex_name;
+ decl->parent = GetOrAddType(type.descriptor());
+ decl->prototype = GetOrEncodeProto(prototype);
+
+ // update the index -> ir node map (see tools/dexter/slicer/dex_ir_builder.cc)
+ auto new_index = dex_file_->methods_indexes.AllocateIndex();
+ auto& ir_node = dex_file_->methods_map[new_index];
+ SLICER_CHECK(ir_node == nullptr);
+ ir_node = decl;
+ decl->orig_index = new_index;
+
+ entry = {id, decl};
+ }
+
+ return entry;
+}
+
+ir::Proto* DexBuilder::GetOrEncodeProto(Prototype prototype) {
+ ir::Proto*& ir_proto = proto_map_[prototype];
+ if (ir_proto == nullptr) {
+ ir_proto = prototype.Encode(this);
+ }
+ return ir_proto;
}
} // namespace dex
diff --git a/startop/view_compiler/dex_builder.h b/startop/view_compiler/dex_builder.h
index d280abce21f5..e46655e0d429 100644
--- a/startop/view_compiler/dex_builder.h
+++ b/startop/view_compiler/dex_builder.h
@@ -17,7 +17,9 @@
#define DEX_BUILDER_H_
#include <map>
+#include <optional>
#include <string>
+#include <unordered_map>
#include <vector>
#include "slicer/dex_ir.h"
@@ -45,7 +47,7 @@ class TrackingAllocator : public ::dex::Writer::Allocator {
virtual void Free(void* ptr);
private:
- std::map<void*, std::unique_ptr<uint8_t[]>> allocations_;
+ std::unordered_map<void*, std::unique_ptr<uint8_t[]>> allocations_;
};
// Represents a DEX type descriptor.
@@ -57,11 +59,17 @@ class TypeDescriptor {
static const TypeDescriptor Int();
static const TypeDescriptor Void();
+ // Creates a type descriptor from a fully-qualified class name. For example, it turns the class
+ // name java.lang.Object into the descriptor Ljava/lang/Object.
+ static TypeDescriptor FromClassname(const std::string& name);
+
// Return the full descriptor, such as I or Ljava/lang/Object
const std::string& descriptor() const { return descriptor_; }
// Return the shorty descriptor, such as I or L
std::string short_descriptor() const { return descriptor().substr(0, 1); }
+ bool operator<(const TypeDescriptor& rhs) const { return descriptor_ < rhs.descriptor_; }
+
private:
TypeDescriptor(std::string descriptor) : descriptor_{descriptor} {}
@@ -82,11 +90,98 @@ class Prototype {
// Get the shorty descriptor, such as VII for (Int, Int) -> Void
std::string Shorty() const;
+ bool operator<(const Prototype& rhs) const {
+ return std::make_tuple(return_type_, param_types_) <
+ std::make_tuple(rhs.return_type_, rhs.param_types_);
+ }
+
private:
const TypeDescriptor return_type_;
const std::vector<TypeDescriptor> param_types_;
};
+// Represents a DEX register or constant. We separate regular registers and parameters
+// because we will not know the real parameter id until after all instructions
+// have been generated.
+class Value {
+ public:
+ static constexpr Value Local(size_t id) { return Value{id, Kind::kLocalRegister}; }
+ static constexpr Value Parameter(size_t id) { return Value{id, Kind::kParameter}; }
+ static constexpr Value Immediate(size_t value) { return Value{value, Kind::kImmediate}; }
+
+ bool is_register() const { return kind_ == Kind::kLocalRegister; }
+ bool is_parameter() const { return kind_ == Kind::kParameter; }
+ bool is_immediate() const { return kind_ == Kind::kImmediate; }
+
+ size_t value() const { return value_; }
+
+ private:
+ enum class Kind { kLocalRegister, kParameter, kImmediate };
+
+ const size_t value_;
+ const Kind kind_;
+
+ constexpr Value(size_t value, Kind kind) : value_{value}, kind_{kind} {}
+};
+
+// A virtual instruction. We convert these to real instructions in MethodBuilder::Encode.
+// Virtual instructions are needed to keep track of information that is not known until all of the
+// code is generated. This information includes things like how many local registers are created and
+// branch target locations.
+class Instruction {
+ public:
+ // The operation performed by this instruction. These are virtual instructions that do not
+ // correspond exactly to DEX instructions.
+ enum class Op { kReturn, kMove, kInvokeVirtual };
+
+ ////////////////////////
+ // Named Constructors //
+ ////////////////////////
+
+ // For instructions with no return value and no arguments.
+ static inline Instruction OpNoArgs(Op opcode) {
+ return Instruction{opcode, /*method_id*/ 0, /*dest*/ {}};
+ }
+ // For most instructions, which take some number of arguments and have an optional return value.
+ template <typename... T>
+ static inline Instruction OpWithArgs(Op opcode, std::optional<const Value> dest, T... args) {
+ return Instruction{opcode, /*method_id*/ 0, dest, args...};
+ }
+ // For method calls.
+ template <typename... T>
+ static inline Instruction InvokeVirtual(size_t method_id, std::optional<const Value> dest,
+ Value this_arg, T... args) {
+ return Instruction{Op::kInvokeVirtual, method_id, dest, this_arg, args...};
+ }
+
+ ///////////////
+ // Accessors //
+ ///////////////
+
+ Op opcode() const { return opcode_; }
+ size_t method_id() const { return method_id_; }
+ const std::optional<const Value>& dest() const { return dest_; }
+ const std::vector<const Value>& args() const { return args_; }
+
+ private:
+ inline Instruction(Op opcode, size_t method_id, std::optional<const Value> dest)
+ : opcode_{opcode}, method_id_{method_id}, dest_{dest}, args_{} {}
+
+ template <typename... T>
+ inline constexpr Instruction(Op opcode, size_t method_id, std::optional<const Value> dest,
+ T... args)
+ : opcode_{opcode}, method_id_{method_id}, dest_{dest}, args_{args...} {}
+
+ const Op opcode_;
+ // The index of the method to invoke, for kInvokeVirtual and similar opcodes.
+ const size_t method_id_{0};
+ const std::optional<const Value> dest_;
+ const std::vector<const Value> args_;
+};
+
+// Needed for CHECK_EQ, DCHECK_EQ, etc.
+std::ostream& operator<<(std::ostream& out, const Instruction::Op& opcode);
+
// Tools to help build methods and their bodies.
class MethodBuilder {
public:
@@ -95,42 +190,53 @@ class MethodBuilder {
// Encode the method into DEX format.
ir::EncodedMethod* Encode();
- // Registers are just represented by their number.
- using Register = size_t;
-
// Create a new register to be used to storing values. Note that these are not SSA registers, like
// might be expected in similar code generators. This does no liveness tracking or anything, so
// it's up to the caller to reuse registers as appropriate.
- Register MakeRegister();
+ Value MakeRegister();
/////////////////////////////////
// Instruction builder methods //
/////////////////////////////////
+ void AddInstruction(Instruction instruction);
+
// return-void
void BuildReturn();
- void BuildReturn(Register src);
+ void BuildReturn(Value src);
// const/4
- void BuildConst4(Register target, int value);
+ void BuildConst4(Value target, int value);
// TODO: add builders for more instructions
private:
+ void EncodeInstructions();
+ void EncodeInstruction(const Instruction& instruction);
+ void EncodeReturn(const Instruction& instruction);
+ void EncodeMove(const Instruction& instruction);
+ void EncodeInvokeVirtual(const Instruction& instruction);
+
+ // Converts a register or parameter to its DEX register number.
+ size_t RegisterValue(Value value) const;
+
DexBuilder* dex_;
ir::Class* class_;
ir::MethodDecl* decl_;
- // A buffer to hold instructions we are generating.
+ // A list of the instructions we will eventually encode.
+ std::vector<Instruction> instructions_;
+
+ // A buffer to hold instructions that have been encoded.
std::vector<::dex::u2> buffer_;
// How many registers we've allocated
- size_t num_registers_;
+ size_t num_registers_{0};
};
// A helper to build class definitions.
class ClassBuilder {
public:
- ClassBuilder(DexBuilder* parent, ir::Class* class_def);
+ ClassBuilder(DexBuilder* parent, const std::string& name, ir::Class* class_def);
void set_source_file(const std::string& source);
@@ -139,8 +245,15 @@ class ClassBuilder {
MethodBuilder CreateMethod(const std::string& name, Prototype prototype);
private:
- DexBuilder* parent_;
- ir::Class* class_;
+ DexBuilder* const parent_;
+ const TypeDescriptor type_descriptor_;
+ ir::Class* const class_;
+};
+
+// Keeps track of information needed to manipulate or call a method.
+struct MethodDeclData {
+ size_t id;
+ ir::MethodDecl* decl;
};
// Builds Dex files from scratch.
@@ -163,10 +276,19 @@ class DexBuilder {
ClassBuilder MakeClass(const std::string& name);
// Add a type for the given descriptor, or return the existing one if it already exists.
- // See the TypeDescriptor class for help generating these.
+ // See the TypeDescriptor class for help generating these. GetOrAddType can be used to declare
+ // imported classes.
ir::Type* GetOrAddType(const std::string& descriptor);
+ // Returns the method id for the method, creating it if it has not been created yet.
+ const MethodDeclData& GetOrDeclareMethod(TypeDescriptor type, const std::string& name,
+ Prototype prototype);
+
private:
+ // Looks up the ir::Proto* corresponding to this given prototype, or creates one if it does not
+ // exist.
+ ir::Proto* GetOrEncodeProto(Prototype prototype);
+
std::shared_ptr<ir::DexFile> dex_file_;
// allocator_ is needed to be able to encode the image.
@@ -177,10 +299,29 @@ class DexBuilder {
std::vector<std::unique_ptr<uint8_t[]>> string_data_;
// Keep track of what types we've defined so we can look them up later.
- std::map<std::string, ir::Type*> types_by_descriptor_;
+ std::unordered_map<std::string, ir::Type*> types_by_descriptor_;
+
+ struct MethodDescriptor {
+ TypeDescriptor type;
+ std::string name;
+ Prototype prototype;
+
+ inline bool operator<(const MethodDescriptor& rhs) const {
+ return std::make_tuple(type, name, prototype) <
+ std::make_tuple(rhs.type, rhs.name, rhs.prototype);
+ }
+ };
+
+ // Maps method declarations to their method index. This is needed to encode references to them.
+ // When we go to actually write the DEX file, slicer will re-assign these after correctly sorting
+ // the methods list.
+ std::map<MethodDescriptor, MethodDeclData> method_id_map_;
// Keep track of what strings we've defined so we can look them up later.
- std::map<std::string, ir::String*> strings_;
+ std::unordered_map<std::string, ir::String*> strings_;
+
+ // Keep track of already-encoded protos.
+ std::map<Prototype, ir::Proto*> proto_map_;
};
} // namespace dex
diff --git a/startop/view_compiler/dex_builder_test.cc b/startop/view_compiler/dex_builder_test.cc
index 0d8b8541caeb..61c86b4091b3 100644
--- a/startop/view_compiler/dex_builder_test.cc
+++ b/startop/view_compiler/dex_builder_test.cc
@@ -40,6 +40,12 @@ bool EncodeAndVerify(DexBuilder* dex_file) {
return loaded_dex_file != nullptr;
}
+// Write out and verify a DEX file that corresponds to:
+//
+// package dextest;
+// public class DexTest {
+// public static void foo() {}
+// }
TEST(DexBuilderTest, VerifyDexWithClassMethod) {
DexBuilder dex_file;
@@ -67,6 +73,12 @@ TEST(DexBuilderTest, VerifyBadDexWithClassMethod) {
EXPECT_FALSE(EncodeAndVerify(&dex_file));
}
+// Write out and verify a DEX file that corresponds to:
+//
+// package dextest;
+// public class DexTest {
+// public static int foo() { return 5; }
+// }
TEST(DexBuilderTest, VerifyDexReturn5) {
DexBuilder dex_file;
@@ -80,3 +92,51 @@ TEST(DexBuilderTest, VerifyDexReturn5) {
EXPECT_TRUE(EncodeAndVerify(&dex_file));
}
+
+// Write out and verify a DEX file that corresponds to:
+//
+// package dextest;
+// public class DexTest {
+// public static int foo(int x) { return x; }
+// }
+TEST(DexBuilderTest, VerifyDexReturnIntParam) {
+ DexBuilder dex_file;
+
+ auto cbuilder{dex_file.MakeClass("dextest.DexTest")};
+
+ auto method{
+ cbuilder.CreateMethod("foo", Prototype{TypeDescriptor::Int(), TypeDescriptor::Int()})};
+ method.BuildReturn(Value::Parameter(0));
+ method.Encode();
+
+ EXPECT_TRUE(EncodeAndVerify(&dex_file));
+}
+
+// Write out and verify a DEX file that corresponds to:
+//
+// package dextest;
+// public class DexTest {
+// public static int foo(String s) { return s.length(); }
+// }
+TEST(DexBuilderTest, VerifyDexCallStringLength) {
+ DexBuilder dex_file;
+
+ auto cbuilder{dex_file.MakeClass("dextest.DexTest")};
+
+ MethodBuilder method{cbuilder.CreateMethod(
+ "foo", Prototype{TypeDescriptor::Int(), TypeDescriptor::FromClassname("java.lang.String")})};
+
+ Value result = method.MakeRegister();
+
+ MethodDeclData string_length =
+ dex_file.GetOrDeclareMethod(TypeDescriptor::FromClassname("java.lang.String"),
+ "length",
+ Prototype{TypeDescriptor::Int()});
+
+ method.AddInstruction(Instruction::InvokeVirtual(string_length.id, result, Value::Parameter(0)));
+ method.BuildReturn(result);
+
+ method.Encode();
+
+ EXPECT_TRUE(EncodeAndVerify(&dex_file));
+}