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// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef V8_CODE_STUBS_H_
#define V8_CODE_STUBS_H_
#include "allocation.h"
#include "globals.h"
#include "codegen.h"
namespace v8 {
namespace internal {
// List of code stubs used on all platforms.
#define CODE_STUB_LIST_ALL_PLATFORMS(V) \
V(CallFunction) \
V(CallConstruct) \
V(UnaryOp) \
V(BinaryOp) \
V(StringAdd) \
V(SubString) \
V(StringCompare) \
V(Compare) \
V(CompareIC) \
V(MathPow) \
V(RecordWrite) \
V(StoreBufferOverflow) \
V(RegExpExec) \
V(TranscendentalCache) \
V(Instanceof) \
V(ConvertToDouble) \
V(WriteInt32ToHeapNumber) \
V(StackCheck) \
V(Interrupt) \
V(FastNewClosure) \
V(FastNewContext) \
V(FastNewBlockContext) \
V(FastCloneShallowArray) \
V(FastCloneShallowObject) \
V(ToBoolean) \
V(ToNumber) \
V(ArgumentsAccess) \
V(RegExpConstructResult) \
V(NumberToString) \
V(CEntry) \
V(JSEntry) \
V(KeyedLoadElement) \
V(KeyedStoreElement) \
V(DebuggerStatement) \
V(StringDictionaryLookup) \
V(ElementsTransitionAndStore) \
V(StoreArrayLiteralElement)
// List of code stubs only used on ARM platforms.
#ifdef V8_TARGET_ARCH_ARM
#define CODE_STUB_LIST_ARM(V) \
V(GetProperty) \
V(SetProperty) \
V(InvokeBuiltin) \
V(RegExpCEntry) \
V(DirectCEntry)
#else
#define CODE_STUB_LIST_ARM(V)
#endif
// List of code stubs only used on MIPS platforms.
#ifdef V8_TARGET_ARCH_MIPS
#define CODE_STUB_LIST_MIPS(V) \
V(RegExpCEntry) \
V(DirectCEntry)
#else
#define CODE_STUB_LIST_MIPS(V)
#endif
// Combined list of code stubs.
#define CODE_STUB_LIST(V) \
CODE_STUB_LIST_ALL_PLATFORMS(V) \
CODE_STUB_LIST_ARM(V) \
CODE_STUB_LIST_MIPS(V)
// Mode to overwrite BinaryExpression values.
enum OverwriteMode { NO_OVERWRITE, OVERWRITE_LEFT, OVERWRITE_RIGHT };
enum UnaryOverwriteMode { UNARY_OVERWRITE, UNARY_NO_OVERWRITE };
// Stub is base classes of all stubs.
class CodeStub BASE_EMBEDDED {
public:
enum Major {
#define DEF_ENUM(name) name,
CODE_STUB_LIST(DEF_ENUM)
#undef DEF_ENUM
NoCache, // marker for stubs that do custom caching
NUMBER_OF_IDS
};
// Retrieve the code for the stub. Generate the code if needed.
Handle<Code> GetCode();
static Major MajorKeyFromKey(uint32_t key) {
return static_cast<Major>(MajorKeyBits::decode(key));
}
static int MinorKeyFromKey(uint32_t key) {
return MinorKeyBits::decode(key);
}
// Gets the major key from a code object that is a code stub or binary op IC.
static Major GetMajorKey(Code* code_stub) {
return static_cast<Major>(code_stub->major_key());
}
static const char* MajorName(Major major_key, bool allow_unknown_keys);
virtual ~CodeStub() {}
bool CompilingCallsToThisStubIsGCSafe() {
bool is_pregenerated = IsPregenerated();
Code* code = NULL;
CHECK(!is_pregenerated || FindCodeInCache(&code));
return is_pregenerated;
}
// See comment above, where Instanceof is defined.
virtual bool IsPregenerated() { return false; }
static void GenerateStubsAheadOfTime();
static void GenerateFPStubs();
// Some stubs put untagged junk on the stack that cannot be scanned by the
// GC. This means that we must be statically sure that no GC can occur while
// they are running. If that is the case they should override this to return
// true, which will cause an assertion if we try to call something that can
// GC or if we try to put a stack frame on top of the junk, which would not
// result in a traversable stack.
virtual bool SometimesSetsUpAFrame() { return true; }
// Lookup the code in the (possibly custom) cache.
bool FindCodeInCache(Code** code_out);
protected:
static const int kMajorBits = 6;
static const int kMinorBits = kBitsPerInt - kSmiTagSize - kMajorBits;
private:
// Nonvirtual wrapper around the stub-specific Generate function. Call
// this function to set up the macro assembler and generate the code.
void GenerateCode(MacroAssembler* masm);
// Generates the assembler code for the stub.
virtual void Generate(MacroAssembler* masm) = 0;
// Perform bookkeeping required after code generation when stub code is
// initially generated.
void RecordCodeGeneration(Code* code, MacroAssembler* masm);
// Finish the code object after it has been generated.
virtual void FinishCode(Handle<Code> code) { }
// Activate newly generated stub. Is called after
// registering stub in the stub cache.
virtual void Activate(Code* code) { }
// Returns information for computing the number key.
virtual Major MajorKey() = 0;
virtual int MinorKey() = 0;
// BinaryOpStub needs to override this.
virtual int GetCodeKind();
// BinaryOpStub needs to override this.
virtual InlineCacheState GetICState() {
return UNINITIALIZED;
}
// Add the code to a specialized cache, specific to an individual
// stub type. Please note, this method must add the code object to a
// roots object, otherwise we will remove the code during GC.
virtual void AddToSpecialCache(Handle<Code> new_object) { }
// Find code in a specialized cache, work is delegated to the specific stub.
virtual bool FindCodeInSpecialCache(Code** code_out) { return false; }
// If a stub uses a special cache override this.
virtual bool UseSpecialCache() { return false; }
// Returns a name for logging/debugging purposes.
SmartArrayPointer<const char> GetName();
virtual void PrintName(StringStream* stream);
// Returns whether the code generated for this stub needs to be allocated as
// a fixed (non-moveable) code object.
virtual bool NeedsImmovableCode() { return false; }
// Computes the key based on major and minor.
uint32_t GetKey() {
ASSERT(static_cast<int>(MajorKey()) < NUMBER_OF_IDS);
return MinorKeyBits::encode(MinorKey()) |
MajorKeyBits::encode(MajorKey());
}
class MajorKeyBits: public BitField<uint32_t, 0, kMajorBits> {};
class MinorKeyBits: public BitField<uint32_t, kMajorBits, kMinorBits> {};
friend class BreakPointIterator;
};
// Helper interface to prepare to/restore after making runtime calls.
class RuntimeCallHelper {
public:
virtual ~RuntimeCallHelper() {}
virtual void BeforeCall(MacroAssembler* masm) const = 0;
virtual void AfterCall(MacroAssembler* masm) const = 0;
protected:
RuntimeCallHelper() {}
private:
DISALLOW_COPY_AND_ASSIGN(RuntimeCallHelper);
};
} } // namespace v8::internal
#if V8_TARGET_ARCH_IA32
#include "ia32/code-stubs-ia32.h"
#elif V8_TARGET_ARCH_X64
#include "x64/code-stubs-x64.h"
#elif V8_TARGET_ARCH_ARM
#include "arm/code-stubs-arm.h"
#elif V8_TARGET_ARCH_MIPS
#include "mips/code-stubs-mips.h"
#else
#error Unsupported target architecture.
#endif
namespace v8 {
namespace internal {
// RuntimeCallHelper implementation used in stubs: enters/leaves a
// newly created internal frame before/after the runtime call.
class StubRuntimeCallHelper : public RuntimeCallHelper {
public:
StubRuntimeCallHelper() {}
virtual void BeforeCall(MacroAssembler* masm) const;
virtual void AfterCall(MacroAssembler* masm) const;
};
// Trivial RuntimeCallHelper implementation.
class NopRuntimeCallHelper : public RuntimeCallHelper {
public:
NopRuntimeCallHelper() {}
virtual void BeforeCall(MacroAssembler* masm) const {}
virtual void AfterCall(MacroAssembler* masm) const {}
};
class StackCheckStub : public CodeStub {
public:
StackCheckStub() { }
void Generate(MacroAssembler* masm);
private:
Major MajorKey() { return StackCheck; }
int MinorKey() { return 0; }
};
class InterruptStub : public CodeStub {
public:
InterruptStub() { }
void Generate(MacroAssembler* masm);
private:
Major MajorKey() { return Interrupt; }
int MinorKey() { return 0; }
};
class ToNumberStub: public CodeStub {
public:
ToNumberStub() { }
void Generate(MacroAssembler* masm);
private:
Major MajorKey() { return ToNumber; }
int MinorKey() { return 0; }
};
class FastNewClosureStub : public CodeStub {
public:
explicit FastNewClosureStub(LanguageMode language_mode)
: language_mode_(language_mode) { }
void Generate(MacroAssembler* masm);
private:
Major MajorKey() { return FastNewClosure; }
int MinorKey() { return language_mode_ == CLASSIC_MODE
? kNonStrictMode : kStrictMode; }
LanguageMode language_mode_;
};
class FastNewContextStub : public CodeStub {
public:
static const int kMaximumSlots = 64;
explicit FastNewContextStub(int slots) : slots_(slots) {
ASSERT(slots_ > 0 && slots_ <= kMaximumSlots);
}
void Generate(MacroAssembler* masm);
private:
int slots_;
Major MajorKey() { return FastNewContext; }
int MinorKey() { return slots_; }
};
class FastNewBlockContextStub : public CodeStub {
public:
static const int kMaximumSlots = 64;
explicit FastNewBlockContextStub(int slots) : slots_(slots) {
ASSERT(slots_ > 0 && slots_ <= kMaximumSlots);
}
void Generate(MacroAssembler* masm);
private:
int slots_;
Major MajorKey() { return FastNewBlockContext; }
int MinorKey() { return slots_; }
};
class FastCloneShallowArrayStub : public CodeStub {
public:
// Maximum length of copied elements array.
static const int kMaximumClonedLength = 8;
enum Mode {
CLONE_ELEMENTS,
CLONE_DOUBLE_ELEMENTS,
COPY_ON_WRITE_ELEMENTS,
CLONE_ANY_ELEMENTS
};
FastCloneShallowArrayStub(Mode mode, int length)
: mode_(mode),
length_((mode == COPY_ON_WRITE_ELEMENTS) ? 0 : length) {
ASSERT_GE(length_, 0);
ASSERT_LE(length_, kMaximumClonedLength);
}
void Generate(MacroAssembler* masm);
private:
Mode mode_;
int length_;
Major MajorKey() { return FastCloneShallowArray; }
int MinorKey() {
ASSERT(mode_ == 0 || mode_ == 1 || mode_ == 2 || mode_ == 3);
return length_ * 4 + mode_;
}
};
class FastCloneShallowObjectStub : public CodeStub {
public:
// Maximum number of properties in copied object.
static const int kMaximumClonedProperties = 6;
explicit FastCloneShallowObjectStub(int length) : length_(length) {
ASSERT_GE(length_, 0);
ASSERT_LE(length_, kMaximumClonedProperties);
}
void Generate(MacroAssembler* masm);
private:
int length_;
Major MajorKey() { return FastCloneShallowObject; }
int MinorKey() { return length_; }
};
class InstanceofStub: public CodeStub {
public:
enum Flags {
kNoFlags = 0,
kArgsInRegisters = 1 << 0,
kCallSiteInlineCheck = 1 << 1,
kReturnTrueFalseObject = 1 << 2
};
explicit InstanceofStub(Flags flags) : flags_(flags) { }
static Register left();
static Register right();
void Generate(MacroAssembler* masm);
private:
Major MajorKey() { return Instanceof; }
int MinorKey() { return static_cast<int>(flags_); }
bool HasArgsInRegisters() const {
return (flags_ & kArgsInRegisters) != 0;
}
bool HasCallSiteInlineCheck() const {
return (flags_ & kCallSiteInlineCheck) != 0;
}
bool ReturnTrueFalseObject() const {
return (flags_ & kReturnTrueFalseObject) != 0;
}
virtual void PrintName(StringStream* stream);
Flags flags_;
};
class MathPowStub: public CodeStub {
public:
enum ExponentType { INTEGER, DOUBLE, TAGGED, ON_STACK};
explicit MathPowStub(ExponentType exponent_type)
: exponent_type_(exponent_type) { }
virtual void Generate(MacroAssembler* masm);
private:
virtual CodeStub::Major MajorKey() { return MathPow; }
virtual int MinorKey() { return exponent_type_; }
ExponentType exponent_type_;
};
class ICCompareStub: public CodeStub {
public:
ICCompareStub(Token::Value op, CompareIC::State state)
: op_(op), state_(state) {
ASSERT(Token::IsCompareOp(op));
}
virtual void Generate(MacroAssembler* masm);
void set_known_map(Handle<Map> map) { known_map_ = map; }
private:
class OpField: public BitField<int, 0, 3> { };
class StateField: public BitField<int, 3, 5> { };
virtual void FinishCode(Handle<Code> code) {
code->set_compare_state(state_);
}
virtual CodeStub::Major MajorKey() { return CompareIC; }
virtual int MinorKey();
virtual int GetCodeKind() { return Code::COMPARE_IC; }
void GenerateSmis(MacroAssembler* masm);
void GenerateHeapNumbers(MacroAssembler* masm);
void GenerateSymbols(MacroAssembler* masm);
void GenerateStrings(MacroAssembler* masm);
void GenerateObjects(MacroAssembler* masm);
void GenerateMiss(MacroAssembler* masm);
void GenerateKnownObjects(MacroAssembler* masm);
bool strict() const { return op_ == Token::EQ_STRICT; }
Condition GetCondition() const { return CompareIC::ComputeCondition(op_); }
virtual void AddToSpecialCache(Handle<Code> new_object);
virtual bool FindCodeInSpecialCache(Code** code_out);
virtual bool UseSpecialCache() { return state_ == CompareIC::KNOWN_OBJECTS; }
Token::Value op_;
CompareIC::State state_;
Handle<Map> known_map_;
};
// Flags that control the compare stub code generation.
enum CompareFlags {
NO_COMPARE_FLAGS = 0,
NO_SMI_COMPARE_IN_STUB = 1 << 0,
NO_NUMBER_COMPARE_IN_STUB = 1 << 1,
CANT_BOTH_BE_NAN = 1 << 2
};
enum NaNInformation {
kBothCouldBeNaN,
kCantBothBeNaN
};
class CompareStub: public CodeStub {
public:
CompareStub(Condition cc,
bool strict,
CompareFlags flags,
Register lhs,
Register rhs) :
cc_(cc),
strict_(strict),
never_nan_nan_((flags & CANT_BOTH_BE_NAN) != 0),
include_number_compare_((flags & NO_NUMBER_COMPARE_IN_STUB) == 0),
include_smi_compare_((flags & NO_SMI_COMPARE_IN_STUB) == 0),
lhs_(lhs),
rhs_(rhs) { }
CompareStub(Condition cc,
bool strict,
CompareFlags flags) :
cc_(cc),
strict_(strict),
never_nan_nan_((flags & CANT_BOTH_BE_NAN) != 0),
include_number_compare_((flags & NO_NUMBER_COMPARE_IN_STUB) == 0),
include_smi_compare_((flags & NO_SMI_COMPARE_IN_STUB) == 0),
lhs_(no_reg),
rhs_(no_reg) { }
void Generate(MacroAssembler* masm);
private:
Condition cc_;
bool strict_;
// Only used for 'equal' comparisons. Tells the stub that we already know
// that at least one side of the comparison is not NaN. This allows the
// stub to use object identity in the positive case. We ignore it when
// generating the minor key for other comparisons to avoid creating more
// stubs.
bool never_nan_nan_;
// Do generate the number comparison code in the stub. Stubs without number
// comparison code is used when the number comparison has been inlined, and
// the stub will be called if one of the operands is not a number.
bool include_number_compare_;
// Generate the comparison code for two smi operands in the stub.
bool include_smi_compare_;
// Register holding the left hand side of the comparison if the stub gives
// a choice, no_reg otherwise.
Register lhs_;
// Register holding the right hand side of the comparison if the stub gives
// a choice, no_reg otherwise.
Register rhs_;
// Encoding of the minor key in 16 bits.
class StrictField: public BitField<bool, 0, 1> {};
class NeverNanNanField: public BitField<bool, 1, 1> {};
class IncludeNumberCompareField: public BitField<bool, 2, 1> {};
class IncludeSmiCompareField: public BitField<bool, 3, 1> {};
class RegisterField: public BitField<bool, 4, 1> {};
class ConditionField: public BitField<int, 5, 11> {};
Major MajorKey() { return Compare; }
int MinorKey();
virtual int GetCodeKind() { return Code::COMPARE_IC; }
virtual void FinishCode(Handle<Code> code) {
code->set_compare_state(CompareIC::GENERIC);
}
// Branch to the label if the given object isn't a symbol.
void BranchIfNonSymbol(MacroAssembler* masm,
Label* label,
Register object,
Register scratch);
// Unfortunately you have to run without snapshots to see most of these
// names in the profile since most compare stubs end up in the snapshot.
virtual void PrintName(StringStream* stream);
};
class CEntryStub : public CodeStub {
public:
explicit CEntryStub(int result_size,
SaveFPRegsMode save_doubles = kDontSaveFPRegs)
: result_size_(result_size), save_doubles_(save_doubles) { }
void Generate(MacroAssembler* masm);
// The version of this stub that doesn't save doubles is generated ahead of
// time, so it's OK to call it from other stubs that can't cope with GC during
// their code generation. On machines that always have gp registers (x64) we
// can generate both variants ahead of time.
virtual bool IsPregenerated();
static void GenerateAheadOfTime();
private:
void GenerateCore(MacroAssembler* masm,
Label* throw_normal_exception,
Label* throw_termination_exception,
Label* throw_out_of_memory_exception,
bool do_gc,
bool always_allocate_scope);
// Number of pointers/values returned.
const int result_size_;
SaveFPRegsMode save_doubles_;
Major MajorKey() { return CEntry; }
int MinorKey();
bool NeedsImmovableCode();
};
class JSEntryStub : public CodeStub {
public:
JSEntryStub() { }
void Generate(MacroAssembler* masm) { GenerateBody(masm, false); }
protected:
void GenerateBody(MacroAssembler* masm, bool is_construct);
private:
Major MajorKey() { return JSEntry; }
int MinorKey() { return 0; }
virtual void FinishCode(Handle<Code> code);
int handler_offset_;
};
class JSConstructEntryStub : public JSEntryStub {
public:
JSConstructEntryStub() { }
void Generate(MacroAssembler* masm) { GenerateBody(masm, true); }
private:
int MinorKey() { return 1; }
virtual void PrintName(StringStream* stream) {
stream->Add("JSConstructEntryStub");
}
};
class ArgumentsAccessStub: public CodeStub {
public:
enum Type {
READ_ELEMENT,
NEW_NON_STRICT_FAST,
NEW_NON_STRICT_SLOW,
NEW_STRICT
};
explicit ArgumentsAccessStub(Type type) : type_(type) { }
private:
Type type_;
Major MajorKey() { return ArgumentsAccess; }
int MinorKey() { return type_; }
void Generate(MacroAssembler* masm);
void GenerateReadElement(MacroAssembler* masm);
void GenerateNewStrict(MacroAssembler* masm);
void GenerateNewNonStrictFast(MacroAssembler* masm);
void GenerateNewNonStrictSlow(MacroAssembler* masm);
virtual void PrintName(StringStream* stream);
};
class RegExpExecStub: public CodeStub {
public:
RegExpExecStub() { }
private:
Major MajorKey() { return RegExpExec; }
int MinorKey() { return 0; }
void Generate(MacroAssembler* masm);
};
class RegExpConstructResultStub: public CodeStub {
public:
RegExpConstructResultStub() { }
private:
Major MajorKey() { return RegExpConstructResult; }
int MinorKey() { return 0; }
void Generate(MacroAssembler* masm);
};
class CallFunctionStub: public CodeStub {
public:
CallFunctionStub(int argc, CallFunctionFlags flags)
: argc_(argc), flags_(flags) { }
void Generate(MacroAssembler* masm);
virtual void FinishCode(Handle<Code> code) {
code->set_has_function_cache(RecordCallTarget());
}
static int ExtractArgcFromMinorKey(int minor_key) {
return ArgcBits::decode(minor_key);
}
private:
int argc_;
CallFunctionFlags flags_;
virtual void PrintName(StringStream* stream);
// Minor key encoding in 32 bits with Bitfield <Type, shift, size>.
class FlagBits: public BitField<CallFunctionFlags, 0, 2> {};
class ArgcBits: public BitField<unsigned, 2, 32 - 2> {};
Major MajorKey() { return CallFunction; }
int MinorKey() {
// Encode the parameters in a unique 32 bit value.
return FlagBits::encode(flags_) | ArgcBits::encode(argc_);
}
bool ReceiverMightBeImplicit() {
return (flags_ & RECEIVER_MIGHT_BE_IMPLICIT) != 0;
}
bool RecordCallTarget() {
return (flags_ & RECORD_CALL_TARGET) != 0;
}
};
class CallConstructStub: public CodeStub {
public:
explicit CallConstructStub(CallFunctionFlags flags) : flags_(flags) {}
void Generate(MacroAssembler* masm);
virtual void FinishCode(Handle<Code> code) {
code->set_has_function_cache(RecordCallTarget());
}
private:
CallFunctionFlags flags_;
virtual void PrintName(StringStream* stream);
Major MajorKey() { return CallConstruct; }
int MinorKey() { return flags_; }
bool RecordCallTarget() {
return (flags_ & RECORD_CALL_TARGET) != 0;
}
};
enum StringIndexFlags {
// Accepts smis or heap numbers.
STRING_INDEX_IS_NUMBER,
// Accepts smis or heap numbers that are valid array indices
// (ECMA-262 15.4). Invalid indices are reported as being out of
// range.
STRING_INDEX_IS_ARRAY_INDEX
};
// Generates code implementing String.prototype.charCodeAt.
//
// Only supports the case when the receiver is a string and the index
// is a number (smi or heap number) that is a valid index into the
// string. Additional index constraints are specified by the
// flags. Otherwise, bails out to the provided labels.
//
// Register usage: |object| may be changed to another string in a way
// that doesn't affect charCodeAt/charAt semantics, |index| is
// preserved, |scratch| and |result| are clobbered.
class StringCharCodeAtGenerator {
public:
StringCharCodeAtGenerator(Register object,
Register index,
Register result,
Label* receiver_not_string,
Label* index_not_number,
Label* index_out_of_range,
StringIndexFlags index_flags)
: object_(object),
index_(index),
result_(result),
receiver_not_string_(receiver_not_string),
index_not_number_(index_not_number),
index_out_of_range_(index_out_of_range),
index_flags_(index_flags) {
ASSERT(!result_.is(object_));
ASSERT(!result_.is(index_));
}
// Generates the fast case code. On the fallthrough path |result|
// register contains the result.
void GenerateFast(MacroAssembler* masm);
// Generates the slow case code. Must not be naturally
// reachable. Expected to be put after a ret instruction (e.g., in
// deferred code). Always jumps back to the fast case.
void GenerateSlow(MacroAssembler* masm,
const RuntimeCallHelper& call_helper);
private:
Register object_;
Register index_;
Register result_;
Label* receiver_not_string_;
Label* index_not_number_;
Label* index_out_of_range_;
StringIndexFlags index_flags_;
Label call_runtime_;
Label index_not_smi_;
Label got_smi_index_;
Label exit_;
DISALLOW_COPY_AND_ASSIGN(StringCharCodeAtGenerator);
};
// Generates code for creating a one-char string from a char code.
class StringCharFromCodeGenerator {
public:
StringCharFromCodeGenerator(Register code,
Register result)
: code_(code),
result_(result) {
ASSERT(!code_.is(result_));
}
// Generates the fast case code. On the fallthrough path |result|
// register contains the result.
void GenerateFast(MacroAssembler* masm);
// Generates the slow case code. Must not be naturally
// reachable. Expected to be put after a ret instruction (e.g., in
// deferred code). Always jumps back to the fast case.
void GenerateSlow(MacroAssembler* masm,
const RuntimeCallHelper& call_helper);
private:
Register code_;
Register result_;
Label slow_case_;
Label exit_;
DISALLOW_COPY_AND_ASSIGN(StringCharFromCodeGenerator);
};
// Generates code implementing String.prototype.charAt.
//
// Only supports the case when the receiver is a string and the index
// is a number (smi or heap number) that is a valid index into the
// string. Additional index constraints are specified by the
// flags. Otherwise, bails out to the provided labels.
//
// Register usage: |object| may be changed to another string in a way
// that doesn't affect charCodeAt/charAt semantics, |index| is
// preserved, |scratch1|, |scratch2|, and |result| are clobbered.
class StringCharAtGenerator {
public:
StringCharAtGenerator(Register object,
Register index,
Register scratch,
Register result,
Label* receiver_not_string,
Label* index_not_number,
Label* index_out_of_range,
StringIndexFlags index_flags)
: char_code_at_generator_(object,
index,
scratch,
receiver_not_string,
index_not_number,
index_out_of_range,
index_flags),
char_from_code_generator_(scratch, result) {}
// Generates the fast case code. On the fallthrough path |result|
// register contains the result.
void GenerateFast(MacroAssembler* masm);
// Generates the slow case code. Must not be naturally
// reachable. Expected to be put after a ret instruction (e.g., in
// deferred code). Always jumps back to the fast case.
void GenerateSlow(MacroAssembler* masm,
const RuntimeCallHelper& call_helper);
private:
StringCharCodeAtGenerator char_code_at_generator_;
StringCharFromCodeGenerator char_from_code_generator_;
DISALLOW_COPY_AND_ASSIGN(StringCharAtGenerator);
};
class AllowStubCallsScope {
public:
AllowStubCallsScope(MacroAssembler* masm, bool allow)
: masm_(masm), previous_allow_(masm->allow_stub_calls()) {
masm_->set_allow_stub_calls(allow);
}
~AllowStubCallsScope() {
masm_->set_allow_stub_calls(previous_allow_);
}
private:
MacroAssembler* masm_;
bool previous_allow_;
DISALLOW_COPY_AND_ASSIGN(AllowStubCallsScope);
};
class KeyedLoadElementStub : public CodeStub {
public:
explicit KeyedLoadElementStub(ElementsKind elements_kind)
: elements_kind_(elements_kind)
{ }
Major MajorKey() { return KeyedLoadElement; }
int MinorKey() { return elements_kind_; }
void Generate(MacroAssembler* masm);
private:
ElementsKind elements_kind_;
DISALLOW_COPY_AND_ASSIGN(KeyedLoadElementStub);
};
class KeyedStoreElementStub : public CodeStub {
public:
KeyedStoreElementStub(bool is_js_array,
ElementsKind elements_kind,
KeyedAccessGrowMode grow_mode)
: is_js_array_(is_js_array),
elements_kind_(elements_kind),
grow_mode_(grow_mode) { }
Major MajorKey() { return KeyedStoreElement; }
int MinorKey() {
return ElementsKindBits::encode(elements_kind_) |
IsJSArrayBits::encode(is_js_array_) |
GrowModeBits::encode(grow_mode_);
}
void Generate(MacroAssembler* masm);
private:
class ElementsKindBits: public BitField<ElementsKind, 0, 8> {};
class GrowModeBits: public BitField<KeyedAccessGrowMode, 8, 1> {};
class IsJSArrayBits: public BitField<bool, 9, 1> {};
bool is_js_array_;
ElementsKind elements_kind_;
KeyedAccessGrowMode grow_mode_;
DISALLOW_COPY_AND_ASSIGN(KeyedStoreElementStub);
};
class ToBooleanStub: public CodeStub {
public:
enum Type {
UNDEFINED,
BOOLEAN,
NULL_TYPE,
SMI,
SPEC_OBJECT,
STRING,
HEAP_NUMBER,
NUMBER_OF_TYPES
};
// At most 8 different types can be distinguished, because the Code object
// only has room for a single byte to hold a set of these types. :-P
STATIC_ASSERT(NUMBER_OF_TYPES <= 8);
class Types {
public:
Types() {}
explicit Types(byte bits) : set_(bits) {}
bool IsEmpty() const { return set_.IsEmpty(); }
bool Contains(Type type) const { return set_.Contains(type); }
void Add(Type type) { set_.Add(type); }
byte ToByte() const { return set_.ToIntegral(); }
void Print(StringStream* stream) const;
void TraceTransition(Types to) const;
bool Record(Handle<Object> object);
bool NeedsMap() const;
bool CanBeUndetectable() const;
private:
EnumSet<Type, byte> set_;
};
static Types no_types() { return Types(); }
static Types all_types() { return Types((1 << NUMBER_OF_TYPES) - 1); }
explicit ToBooleanStub(Register tos, Types types = Types())
: tos_(tos), types_(types) { }
void Generate(MacroAssembler* masm);
virtual int GetCodeKind() { return Code::TO_BOOLEAN_IC; }
virtual void PrintName(StringStream* stream);
virtual bool SometimesSetsUpAFrame() { return false; }
private:
Major MajorKey() { return ToBoolean; }
int MinorKey() { return (tos_.code() << NUMBER_OF_TYPES) | types_.ToByte(); }
virtual void FinishCode(Handle<Code> code) {
code->set_to_boolean_state(types_.ToByte());
}
void CheckOddball(MacroAssembler* masm,
Type type,
Heap::RootListIndex value,
bool result);
void GenerateTypeTransition(MacroAssembler* masm);
Register tos_;
Types types_;
};
class ElementsTransitionAndStoreStub : public CodeStub {
public:
ElementsTransitionAndStoreStub(ElementsKind from,
ElementsKind to,
bool is_jsarray,
StrictModeFlag strict_mode,
KeyedAccessGrowMode grow_mode)
: from_(from),
to_(to),
is_jsarray_(is_jsarray),
strict_mode_(strict_mode),
grow_mode_(grow_mode) {}
private:
class FromBits: public BitField<ElementsKind, 0, 8> {};
class ToBits: public BitField<ElementsKind, 8, 8> {};
class IsJSArrayBits: public BitField<bool, 16, 1> {};
class StrictModeBits: public BitField<StrictModeFlag, 17, 1> {};
class GrowModeBits: public BitField<KeyedAccessGrowMode, 18, 1> {};
Major MajorKey() { return ElementsTransitionAndStore; }
int MinorKey() {
return FromBits::encode(from_) |
ToBits::encode(to_) |
IsJSArrayBits::encode(is_jsarray_) |
StrictModeBits::encode(strict_mode_) |
GrowModeBits::encode(grow_mode_);
}
void Generate(MacroAssembler* masm);
ElementsKind from_;
ElementsKind to_;
bool is_jsarray_;
StrictModeFlag strict_mode_;
KeyedAccessGrowMode grow_mode_;
DISALLOW_COPY_AND_ASSIGN(ElementsTransitionAndStoreStub);
};
class StoreArrayLiteralElementStub : public CodeStub {
public:
explicit StoreArrayLiteralElementStub() {}
private:
Major MajorKey() { return StoreArrayLiteralElement; }
int MinorKey() { return 0; }
void Generate(MacroAssembler* masm);
DISALLOW_COPY_AND_ASSIGN(StoreArrayLiteralElementStub);
};
} } // namespace v8::internal
#endif // V8_CODE_STUBS_H_