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Diffstat (limited to 'deps/v8/src/x64/code-stubs-x64.cc')
| -rw-r--r-- | deps/v8/src/x64/code-stubs-x64.cc | 4015 |
1 files changed, 4015 insertions, 0 deletions
diff --git a/deps/v8/src/x64/code-stubs-x64.cc b/deps/v8/src/x64/code-stubs-x64.cc new file mode 100644 index 0000000000..c75b9455b2 --- /dev/null +++ b/deps/v8/src/x64/code-stubs-x64.cc @@ -0,0 +1,4015 @@ +// Copyright 2010 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. + +#include "v8.h" + +#if defined(V8_TARGET_ARCH_X64) + +#include "bootstrapper.h" +#include "code-stubs.h" +#include "regexp-macro-assembler.h" + +namespace v8 { +namespace internal { + +#define __ ACCESS_MASM(masm) +void FastNewClosureStub::Generate(MacroAssembler* masm) { + // Create a new closure from the given function info in new + // space. Set the context to the current context in rsi. + Label gc; + __ AllocateInNewSpace(JSFunction::kSize, rax, rbx, rcx, &gc, TAG_OBJECT); + + // Get the function info from the stack. + __ movq(rdx, Operand(rsp, 1 * kPointerSize)); + + // Compute the function map in the current global context and set that + // as the map of the allocated object. + __ movq(rcx, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX))); + __ movq(rcx, FieldOperand(rcx, GlobalObject::kGlobalContextOffset)); + __ movq(rcx, Operand(rcx, Context::SlotOffset(Context::FUNCTION_MAP_INDEX))); + __ movq(FieldOperand(rax, JSObject::kMapOffset), rcx); + + // Initialize the rest of the function. We don't have to update the + // write barrier because the allocated object is in new space. + __ LoadRoot(rbx, Heap::kEmptyFixedArrayRootIndex); + __ LoadRoot(rcx, Heap::kTheHoleValueRootIndex); + __ movq(FieldOperand(rax, JSObject::kPropertiesOffset), rbx); + __ movq(FieldOperand(rax, JSObject::kElementsOffset), rbx); + __ movq(FieldOperand(rax, JSFunction::kPrototypeOrInitialMapOffset), rcx); + __ movq(FieldOperand(rax, JSFunction::kSharedFunctionInfoOffset), rdx); + __ movq(FieldOperand(rax, JSFunction::kContextOffset), rsi); + __ movq(FieldOperand(rax, JSFunction::kLiteralsOffset), rbx); + + // Initialize the code pointer in the function to be the one + // found in the shared function info object. + __ movq(rdx, FieldOperand(rdx, SharedFunctionInfo::kCodeOffset)); + __ lea(rdx, FieldOperand(rdx, Code::kHeaderSize)); + __ movq(FieldOperand(rax, JSFunction::kCodeEntryOffset), rdx); + + + // Return and remove the on-stack parameter. + __ ret(1 * kPointerSize); + + // Create a new closure through the slower runtime call. + __ bind(&gc); + __ pop(rcx); // Temporarily remove return address. + __ pop(rdx); + __ push(rsi); + __ push(rdx); + __ push(rcx); // Restore return address. + __ TailCallRuntime(Runtime::kNewClosure, 2, 1); +} + + +void FastNewContextStub::Generate(MacroAssembler* masm) { + // Try to allocate the context in new space. + Label gc; + int length = slots_ + Context::MIN_CONTEXT_SLOTS; + __ AllocateInNewSpace((length * kPointerSize) + FixedArray::kHeaderSize, + rax, rbx, rcx, &gc, TAG_OBJECT); + + // Get the function from the stack. + __ movq(rcx, Operand(rsp, 1 * kPointerSize)); + + // Setup the object header. + __ LoadRoot(kScratchRegister, Heap::kContextMapRootIndex); + __ movq(FieldOperand(rax, HeapObject::kMapOffset), kScratchRegister); + __ Move(FieldOperand(rax, FixedArray::kLengthOffset), Smi::FromInt(length)); + + // Setup the fixed slots. + __ xor_(rbx, rbx); // Set to NULL. + __ movq(Operand(rax, Context::SlotOffset(Context::CLOSURE_INDEX)), rcx); + __ movq(Operand(rax, Context::SlotOffset(Context::FCONTEXT_INDEX)), rax); + __ movq(Operand(rax, Context::SlotOffset(Context::PREVIOUS_INDEX)), rbx); + __ movq(Operand(rax, Context::SlotOffset(Context::EXTENSION_INDEX)), rbx); + + // Copy the global object from the surrounding context. + __ movq(rbx, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX))); + __ movq(Operand(rax, Context::SlotOffset(Context::GLOBAL_INDEX)), rbx); + + // Initialize the rest of the slots to undefined. + __ LoadRoot(rbx, Heap::kUndefinedValueRootIndex); + for (int i = Context::MIN_CONTEXT_SLOTS; i < length; i++) { + __ movq(Operand(rax, Context::SlotOffset(i)), rbx); + } + + // Return and remove the on-stack parameter. + __ movq(rsi, rax); + __ ret(1 * kPointerSize); + + // Need to collect. Call into runtime system. + __ bind(&gc); + __ TailCallRuntime(Runtime::kNewContext, 1, 1); +} + + +void FastCloneShallowArrayStub::Generate(MacroAssembler* masm) { + // Stack layout on entry: + // + // [rsp + kPointerSize]: constant elements. + // [rsp + (2 * kPointerSize)]: literal index. + // [rsp + (3 * kPointerSize)]: literals array. + + // All sizes here are multiples of kPointerSize. + int elements_size = (length_ > 0) ? FixedArray::SizeFor(length_) : 0; + int size = JSArray::kSize + elements_size; + + // Load boilerplate object into rcx and check if we need to create a + // boilerplate. + Label slow_case; + __ movq(rcx, Operand(rsp, 3 * kPointerSize)); + __ movq(rax, Operand(rsp, 2 * kPointerSize)); + SmiIndex index = masm->SmiToIndex(rax, rax, kPointerSizeLog2); + __ movq(rcx, + FieldOperand(rcx, index.reg, index.scale, FixedArray::kHeaderSize)); + __ CompareRoot(rcx, Heap::kUndefinedValueRootIndex); + __ j(equal, &slow_case); + + if (FLAG_debug_code) { + const char* message; + Heap::RootListIndex expected_map_index; + if (mode_ == CLONE_ELEMENTS) { + message = "Expected (writable) fixed array"; + expected_map_index = Heap::kFixedArrayMapRootIndex; + } else { + ASSERT(mode_ == COPY_ON_WRITE_ELEMENTS); + message = "Expected copy-on-write fixed array"; + expected_map_index = Heap::kFixedCOWArrayMapRootIndex; + } + __ push(rcx); + __ movq(rcx, FieldOperand(rcx, JSArray::kElementsOffset)); + __ CompareRoot(FieldOperand(rcx, HeapObject::kMapOffset), + expected_map_index); + __ Assert(equal, message); + __ pop(rcx); + } + + // Allocate both the JS array and the elements array in one big + // allocation. This avoids multiple limit checks. + __ AllocateInNewSpace(size, rax, rbx, rdx, &slow_case, TAG_OBJECT); + + // Copy the JS array part. + for (int i = 0; i < JSArray::kSize; i += kPointerSize) { + if ((i != JSArray::kElementsOffset) || (length_ == 0)) { + __ movq(rbx, FieldOperand(rcx, i)); + __ movq(FieldOperand(rax, i), rbx); + } + } + + if (length_ > 0) { + // Get hold of the elements array of the boilerplate and setup the + // elements pointer in the resulting object. + __ movq(rcx, FieldOperand(rcx, JSArray::kElementsOffset)); + __ lea(rdx, Operand(rax, JSArray::kSize)); + __ movq(FieldOperand(rax, JSArray::kElementsOffset), rdx); + + // Copy the elements array. + for (int i = 0; i < elements_size; i += kPointerSize) { + __ movq(rbx, FieldOperand(rcx, i)); + __ movq(FieldOperand(rdx, i), rbx); + } + } + + // Return and remove the on-stack parameters. + __ ret(3 * kPointerSize); + + __ bind(&slow_case); + __ TailCallRuntime(Runtime::kCreateArrayLiteralShallow, 3, 1); +} + + +void ToBooleanStub::Generate(MacroAssembler* masm) { + Label false_result, true_result, not_string; + __ movq(rax, Operand(rsp, 1 * kPointerSize)); + + // 'null' => false. + __ CompareRoot(rax, Heap::kNullValueRootIndex); + __ j(equal, &false_result); + + // Get the map and type of the heap object. + // We don't use CmpObjectType because we manipulate the type field. + __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset)); + __ movzxbq(rcx, FieldOperand(rdx, Map::kInstanceTypeOffset)); + + // Undetectable => false. + __ movzxbq(rbx, FieldOperand(rdx, Map::kBitFieldOffset)); + __ and_(rbx, Immediate(1 << Map::kIsUndetectable)); + __ j(not_zero, &false_result); + + // JavaScript object => true. + __ cmpq(rcx, Immediate(FIRST_JS_OBJECT_TYPE)); + __ j(above_equal, &true_result); + + // String value => false iff empty. + __ cmpq(rcx, Immediate(FIRST_NONSTRING_TYPE)); + __ j(above_equal, ¬_string); + __ movq(rdx, FieldOperand(rax, String::kLengthOffset)); + __ SmiTest(rdx); + __ j(zero, &false_result); + __ jmp(&true_result); + + __ bind(¬_string); + __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex); + __ j(not_equal, &true_result); + // HeapNumber => false iff +0, -0, or NaN. + // These three cases set the zero flag when compared to zero using ucomisd. + __ xorpd(xmm0, xmm0); + __ ucomisd(xmm0, FieldOperand(rax, HeapNumber::kValueOffset)); + __ j(zero, &false_result); + // Fall through to |true_result|. + + // Return 1/0 for true/false in rax. + __ bind(&true_result); + __ movq(rax, Immediate(1)); + __ ret(1 * kPointerSize); + __ bind(&false_result); + __ xor_(rax, rax); + __ ret(1 * kPointerSize); +} + + +const char* GenericBinaryOpStub::GetName() { + if (name_ != NULL) return name_; + const int kMaxNameLength = 100; + name_ = Bootstrapper::AllocateAutoDeletedArray(kMaxNameLength); + if (name_ == NULL) return "OOM"; + const char* op_name = Token::Name(op_); + const char* overwrite_name; + switch (mode_) { + case NO_OVERWRITE: overwrite_name = "Alloc"; break; + case OVERWRITE_RIGHT: overwrite_name = "OverwriteRight"; break; + case OVERWRITE_LEFT: overwrite_name = "OverwriteLeft"; break; + default: overwrite_name = "UnknownOverwrite"; break; + } + + OS::SNPrintF(Vector<char>(name_, kMaxNameLength), + "GenericBinaryOpStub_%s_%s%s_%s%s_%s_%s", + op_name, + overwrite_name, + (flags_ & NO_SMI_CODE_IN_STUB) ? "_NoSmiInStub" : "", + args_in_registers_ ? "RegArgs" : "StackArgs", + args_reversed_ ? "_R" : "", + static_operands_type_.ToString(), + BinaryOpIC::GetName(runtime_operands_type_)); + return name_; +} + + +void GenericBinaryOpStub::GenerateCall( + MacroAssembler* masm, + Register left, + Register right) { + if (!ArgsInRegistersSupported()) { + // Pass arguments on the stack. + __ push(left); + __ push(right); + } else { + // The calling convention with registers is left in rdx and right in rax. + Register left_arg = rdx; + Register right_arg = rax; + if (!(left.is(left_arg) && right.is(right_arg))) { + if (left.is(right_arg) && right.is(left_arg)) { + if (IsOperationCommutative()) { + SetArgsReversed(); + } else { + __ xchg(left, right); + } + } else if (left.is(left_arg)) { + __ movq(right_arg, right); + } else if (right.is(right_arg)) { + __ movq(left_arg, left); + } else if (left.is(right_arg)) { + if (IsOperationCommutative()) { + __ movq(left_arg, right); + SetArgsReversed(); + } else { + // Order of moves important to avoid destroying left argument. + __ movq(left_arg, left); + __ movq(right_arg, right); + } + } else if (right.is(left_arg)) { + if (IsOperationCommutative()) { + __ movq(right_arg, left); + SetArgsReversed(); + } else { + // Order of moves important to avoid destroying right argument. + __ movq(right_arg, right); + __ movq(left_arg, left); + } + } else { + // Order of moves is not important. + __ movq(left_arg, left); + __ movq(right_arg, right); + } + } + + // Update flags to indicate that arguments are in registers. + SetArgsInRegisters(); + __ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1); + } + + // Call the stub. + __ CallStub(this); +} + + +void GenericBinaryOpStub::GenerateCall( + MacroAssembler* masm, + Register left, + Smi* right) { + if (!ArgsInRegistersSupported()) { + // Pass arguments on the stack. + __ push(left); + __ Push(right); + } else { + // The calling convention with registers is left in rdx and right in rax. + Register left_arg = rdx; + Register right_arg = rax; + if (left.is(left_arg)) { + __ Move(right_arg, right); + } else if (left.is(right_arg) && IsOperationCommutative()) { + __ Move(left_arg, right); + SetArgsReversed(); + } else { + // For non-commutative operations, left and right_arg might be + // the same register. Therefore, the order of the moves is + // important here in order to not overwrite left before moving + // it to left_arg. + __ movq(left_arg, left); + __ Move(right_arg, right); + } + + // Update flags to indicate that arguments are in registers. + SetArgsInRegisters(); + __ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1); + } + + // Call the stub. + __ CallStub(this); +} + + +void GenericBinaryOpStub::GenerateCall( + MacroAssembler* masm, + Smi* left, + Register right) { + if (!ArgsInRegistersSupported()) { + // Pass arguments on the stack. + __ Push(left); + __ push(right); + } else { + // The calling convention with registers is left in rdx and right in rax. + Register left_arg = rdx; + Register right_arg = rax; + if (right.is(right_arg)) { + __ Move(left_arg, left); + } else if (right.is(left_arg) && IsOperationCommutative()) { + __ Move(right_arg, left); + SetArgsReversed(); + } else { + // For non-commutative operations, right and left_arg might be + // the same register. Therefore, the order of the moves is + // important here in order to not overwrite right before moving + // it to right_arg. + __ movq(right_arg, right); + __ Move(left_arg, left); + } + // Update flags to indicate that arguments are in registers. + SetArgsInRegisters(); + __ IncrementCounter(&Counters::generic_binary_stub_calls_regs, 1); + } + + // Call the stub. + __ CallStub(this); +} + + +class FloatingPointHelper : public AllStatic { + public: + // Load the operands from rdx and rax into xmm0 and xmm1, as doubles. + // If the operands are not both numbers, jump to not_numbers. + // Leaves rdx and rax unchanged. SmiOperands assumes both are smis. + // NumberOperands assumes both are smis or heap numbers. + static void LoadSSE2SmiOperands(MacroAssembler* masm); + static void LoadSSE2NumberOperands(MacroAssembler* masm); + static void LoadSSE2UnknownOperands(MacroAssembler* masm, + Label* not_numbers); + + // Takes the operands in rdx and rax and loads them as integers in rax + // and rcx. + static void LoadAsIntegers(MacroAssembler* masm, + Label* operand_conversion_failure, + Register heap_number_map); + // As above, but we know the operands to be numbers. In that case, + // conversion can't fail. + static void LoadNumbersAsIntegers(MacroAssembler* masm); +}; + + +void GenericBinaryOpStub::GenerateSmiCode(MacroAssembler* masm, Label* slow) { + // 1. Move arguments into rdx, rax except for DIV and MOD, which need the + // dividend in rax and rdx free for the division. Use rax, rbx for those. + Comment load_comment(masm, "-- Load arguments"); + Register left = rdx; + Register right = rax; + if (op_ == Token::DIV || op_ == Token::MOD) { + left = rax; + right = rbx; + if (HasArgsInRegisters()) { + __ movq(rbx, rax); + __ movq(rax, rdx); + } + } + if (!HasArgsInRegisters()) { + __ movq(right, Operand(rsp, 1 * kPointerSize)); + __ movq(left, Operand(rsp, 2 * kPointerSize)); + } + + Label not_smis; + // 2. Smi check both operands. + if (static_operands_type_.IsSmi()) { + // Skip smi check if we know that both arguments are smis. + if (FLAG_debug_code) { + __ AbortIfNotSmi(left); + __ AbortIfNotSmi(right); + } + if (op_ == Token::BIT_OR) { + // Handle OR here, since we do extra smi-checking in the or code below. + __ SmiOr(right, right, left); + GenerateReturn(masm); + return; + } + } else { + if (op_ != Token::BIT_OR) { + // Skip the check for OR as it is better combined with the + // actual operation. + Comment smi_check_comment(masm, "-- Smi check arguments"); + __ JumpIfNotBothSmi(left, right, ¬_smis); + } + } + + // 3. Operands are both smis (except for OR), perform the operation leaving + // the result in rax and check the result if necessary. + Comment perform_smi(masm, "-- Perform smi operation"); + Label use_fp_on_smis; + switch (op_) { + case Token::ADD: { + ASSERT(right.is(rax)); + __ SmiAdd(right, right, left, &use_fp_on_smis); // ADD is commutative. + break; + } + + case Token::SUB: { + __ SmiSub(left, left, right, &use_fp_on_smis); + __ movq(rax, left); + break; + } + + case Token::MUL: + ASSERT(right.is(rax)); + __ SmiMul(right, right, left, &use_fp_on_smis); // MUL is commutative. + break; + + case Token::DIV: + ASSERT(left.is(rax)); + __ SmiDiv(left, left, right, &use_fp_on_smis); + break; + + case Token::MOD: + ASSERT(left.is(rax)); + __ SmiMod(left, left, right, slow); + break; + + case Token::BIT_OR: + ASSERT(right.is(rax)); + __ movq(rcx, right); // Save the right operand. + __ SmiOr(right, right, left); // BIT_OR is commutative. + __ testb(right, Immediate(kSmiTagMask)); + __ j(not_zero, ¬_smis); + break; + + case Token::BIT_AND: + ASSERT(right.is(rax)); + __ SmiAnd(right, right, left); // BIT_AND is commutative. + break; + + case Token::BIT_XOR: + ASSERT(right.is(rax)); + __ SmiXor(right, right, left); // BIT_XOR is commutative. + break; + + case Token::SHL: + case Token::SHR: + case Token::SAR: + switch (op_) { + case Token::SAR: + __ SmiShiftArithmeticRight(left, left, right); + break; + case Token::SHR: + __ SmiShiftLogicalRight(left, left, right, slow); + break; + case Token::SHL: + __ SmiShiftLeft(left, left, right); + break; + default: + UNREACHABLE(); + } + __ movq(rax, left); + break; + + default: + UNREACHABLE(); + break; + } + + // 4. Emit return of result in rax. + GenerateReturn(masm); + + // 5. For some operations emit inline code to perform floating point + // operations on known smis (e.g., if the result of the operation + // overflowed the smi range). + switch (op_) { + case Token::ADD: + case Token::SUB: + case Token::MUL: + case Token::DIV: { + ASSERT(use_fp_on_smis.is_linked()); + __ bind(&use_fp_on_smis); + if (op_ == Token::DIV) { + __ movq(rdx, rax); + __ movq(rax, rbx); + } + // left is rdx, right is rax. + __ AllocateHeapNumber(rbx, rcx, slow); + FloatingPointHelper::LoadSSE2SmiOperands(masm); + switch (op_) { + case Token::ADD: __ addsd(xmm0, xmm1); break; + case Token::SUB: __ subsd(xmm0, xmm1); break; + case Token::MUL: __ mulsd(xmm0, xmm1); break; + case Token::DIV: __ divsd(xmm0, xmm1); break; + default: UNREACHABLE(); + } + __ movsd(FieldOperand(rbx, HeapNumber::kValueOffset), xmm0); + __ movq(rax, rbx); + GenerateReturn(masm); + } + default: + break; + } + + // 6. Non-smi operands, fall out to the non-smi code with the operands in + // rdx and rax. + Comment done_comment(masm, "-- Enter non-smi code"); + __ bind(¬_smis); + + switch (op_) { + case Token::DIV: + case Token::MOD: + // Operands are in rax, rbx at this point. + __ movq(rdx, rax); + __ movq(rax, rbx); + break; + + case Token::BIT_OR: + // Right operand is saved in rcx and rax was destroyed by the smi + // operation. + __ movq(rax, rcx); + break; + + default: + break; + } +} + + +void GenericBinaryOpStub::Generate(MacroAssembler* masm) { + Label call_runtime; + + if (ShouldGenerateSmiCode()) { + GenerateSmiCode(masm, &call_runtime); + } else if (op_ != Token::MOD) { + if (!HasArgsInRegisters()) { + GenerateLoadArguments(masm); + } + } + // Floating point case. + if (ShouldGenerateFPCode()) { + switch (op_) { + case Token::ADD: + case Token::SUB: + case Token::MUL: + case Token::DIV: { + if (runtime_operands_type_ == BinaryOpIC::DEFAULT && + HasSmiCodeInStub()) { + // Execution reaches this point when the first non-smi argument occurs + // (and only if smi code is generated). This is the right moment to + // patch to HEAP_NUMBERS state. The transition is attempted only for + // the four basic operations. The stub stays in the DEFAULT state + // forever for all other operations (also if smi code is skipped). + GenerateTypeTransition(masm); + break; + } + + Label not_floats; + // rax: y + // rdx: x + if (static_operands_type_.IsNumber()) { + if (FLAG_debug_code) { + // Assert at runtime that inputs are only numbers. + __ AbortIfNotNumber(rdx); + __ AbortIfNotNumber(rax); + } + FloatingPointHelper::LoadSSE2NumberOperands(masm); + } else { + FloatingPointHelper::LoadSSE2UnknownOperands(masm, &call_runtime); + } + + switch (op_) { + case Token::ADD: __ addsd(xmm0, xmm1); break; + case Token::SUB: __ subsd(xmm0, xmm1); break; + case Token::MUL: __ mulsd(xmm0, xmm1); break; + case Token::DIV: __ divsd(xmm0, xmm1); break; + default: UNREACHABLE(); + } + // Allocate a heap number, if needed. + Label skip_allocation; + OverwriteMode mode = mode_; + if (HasArgsReversed()) { + if (mode == OVERWRITE_RIGHT) { + mode = OVERWRITE_LEFT; + } else if (mode == OVERWRITE_LEFT) { + mode = OVERWRITE_RIGHT; + } + } + switch (mode) { + case OVERWRITE_LEFT: + __ JumpIfNotSmi(rdx, &skip_allocation); + __ AllocateHeapNumber(rbx, rcx, &call_runtime); + __ movq(rdx, rbx); + __ bind(&skip_allocation); + __ movq(rax, rdx); + break; + case OVERWRITE_RIGHT: + // If the argument in rax is already an object, we skip the + // allocation of a heap number. + __ JumpIfNotSmi(rax, &skip_allocation); + // Fall through! + case NO_OVERWRITE: + // Allocate a heap number for the result. Keep rax and rdx intact + // for the possible runtime call. + __ AllocateHeapNumber(rbx, rcx, &call_runtime); + __ movq(rax, rbx); + __ bind(&skip_allocation); + break; + default: UNREACHABLE(); + } + __ movsd(FieldOperand(rax, HeapNumber::kValueOffset), xmm0); + GenerateReturn(masm); + __ bind(¬_floats); + if (runtime_operands_type_ == BinaryOpIC::DEFAULT && + !HasSmiCodeInStub()) { + // Execution reaches this point when the first non-number argument + // occurs (and only if smi code is skipped from the stub, otherwise + // the patching has already been done earlier in this case branch). + // A perfect moment to try patching to STRINGS for ADD operation. + if (op_ == Token::ADD) { + GenerateTypeTransition(masm); + } + } + break; + } + case Token::MOD: { + // For MOD we go directly to runtime in the non-smi case. + break; + } + case Token::BIT_OR: + case Token::BIT_AND: + case Token::BIT_XOR: + case Token::SAR: + case Token::SHL: + case Token::SHR: { + Label skip_allocation, non_smi_shr_result; + Register heap_number_map = r9; + __ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex); + if (static_operands_type_.IsNumber()) { + if (FLAG_debug_code) { + // Assert at runtime that inputs are only numbers. + __ AbortIfNotNumber(rdx); + __ AbortIfNotNumber(rax); + } + FloatingPointHelper::LoadNumbersAsIntegers(masm); + } else { + FloatingPointHelper::LoadAsIntegers(masm, + &call_runtime, + heap_number_map); + } + switch (op_) { + case Token::BIT_OR: __ orl(rax, rcx); break; + case Token::BIT_AND: __ andl(rax, rcx); break; + case Token::BIT_XOR: __ xorl(rax, rcx); break; + case Token::SAR: __ sarl_cl(rax); break; + case Token::SHL: __ shll_cl(rax); break; + case Token::SHR: { + __ shrl_cl(rax); + // Check if result is negative. This can only happen for a shift + // by zero. + __ testl(rax, rax); + __ j(negative, &non_smi_shr_result); + break; + } + default: UNREACHABLE(); + } + + STATIC_ASSERT(kSmiValueSize == 32); + // Tag smi result and return. + __ Integer32ToSmi(rax, rax); + GenerateReturn(masm); + + // All bit-ops except SHR return a signed int32 that can be + // returned immediately as a smi. + // We might need to allocate a HeapNumber if we shift a negative + // number right by zero (i.e., convert to UInt32). + if (op_ == Token::SHR) { + ASSERT(non_smi_shr_result.is_linked()); + __ bind(&non_smi_shr_result); + // Allocate a heap number if needed. + __ movl(rbx, rax); // rbx holds result value (uint32 value as int64). + switch (mode_) { + case OVERWRITE_LEFT: + case OVERWRITE_RIGHT: + // If the operand was an object, we skip the + // allocation of a heap number. + __ movq(rax, Operand(rsp, mode_ == OVERWRITE_RIGHT ? + 1 * kPointerSize : 2 * kPointerSize)); + __ JumpIfNotSmi(rax, &skip_allocation); + // Fall through! + case NO_OVERWRITE: + // Allocate heap number in new space. + // Not using AllocateHeapNumber macro in order to reuse + // already loaded heap_number_map. + __ AllocateInNewSpace(HeapNumber::kSize, + rax, + rcx, + no_reg, + &call_runtime, + TAG_OBJECT); + // Set the map. + if (FLAG_debug_code) { + __ AbortIfNotRootValue(heap_number_map, + Heap::kHeapNumberMapRootIndex, + "HeapNumberMap register clobbered."); + } + __ movq(FieldOperand(rax, HeapObject::kMapOffset), + heap_number_map); + __ bind(&skip_allocation); + break; + default: UNREACHABLE(); + } + // Store the result in the HeapNumber and return. + __ cvtqsi2sd(xmm0, rbx); + __ movsd(FieldOperand(rax, HeapNumber::kValueOffset), xmm0); + GenerateReturn(masm); + } + + break; + } + default: UNREACHABLE(); break; + } + } + + // If all else fails, use the runtime system to get the correct + // result. If arguments was passed in registers now place them on the + // stack in the correct order below the return address. + __ bind(&call_runtime); + + if (HasArgsInRegisters()) { + GenerateRegisterArgsPush(masm); + } + + switch (op_) { + case Token::ADD: { + // Registers containing left and right operands respectively. + Register lhs, rhs; + + if (HasArgsReversed()) { + lhs = rax; + rhs = rdx; + } else { + lhs = rdx; + rhs = rax; + } + + // Test for string arguments before calling runtime. + Label not_strings, both_strings, not_string1, string1, string1_smi2; + + // If this stub has already generated FP-specific code then the arguments + // are already in rdx and rax. + if (!ShouldGenerateFPCode() && !HasArgsInRegisters()) { + GenerateLoadArguments(masm); + } + + Condition is_smi; + is_smi = masm->CheckSmi(lhs); + __ j(is_smi, ¬_string1); + __ CmpObjectType(lhs, FIRST_NONSTRING_TYPE, r8); + __ j(above_equal, ¬_string1); + + // First argument is a a string, test second. + is_smi = masm->CheckSmi(rhs); + __ j(is_smi, &string1_smi2); + __ CmpObjectType(rhs, FIRST_NONSTRING_TYPE, r9); + __ j(above_equal, &string1); + + // First and second argument are strings. + StringAddStub string_add_stub(NO_STRING_CHECK_IN_STUB); + __ TailCallStub(&string_add_stub); + + __ bind(&string1_smi2); + // First argument is a string, second is a smi. Try to lookup the number + // string for the smi in the number string cache. + NumberToStringStub::GenerateLookupNumberStringCache( + masm, rhs, rbx, rcx, r8, true, &string1); + + // Replace second argument on stack and tailcall string add stub to make + // the result. + __ movq(Operand(rsp, 1 * kPointerSize), rbx); + __ TailCallStub(&string_add_stub); + + // Only first argument is a string. + __ bind(&string1); + __ InvokeBuiltin(Builtins::STRING_ADD_LEFT, JUMP_FUNCTION); + + // First argument was not a string, test second. + __ bind(¬_string1); + is_smi = masm->CheckSmi(rhs); + __ j(is_smi, ¬_strings); + __ CmpObjectType(rhs, FIRST_NONSTRING_TYPE, rhs); + __ j(above_equal, ¬_strings); + + // Only second argument is a string. + __ InvokeBuiltin(Builtins::STRING_ADD_RIGHT, JUMP_FUNCTION); + + __ bind(¬_strings); + // Neither argument is a string. + __ InvokeBuiltin(Builtins::ADD, JUMP_FUNCTION); + break; + } + case Token::SUB: + __ InvokeBuiltin(Builtins::SUB, JUMP_FUNCTION); + break; + case Token::MUL: + __ InvokeBuiltin(Builtins::MUL, JUMP_FUNCTION); + break; + case Token::DIV: + __ InvokeBuiltin(Builtins::DIV, JUMP_FUNCTION); + break; + case Token::MOD: + __ InvokeBuiltin(Builtins::MOD, JUMP_FUNCTION); + break; + case Token::BIT_OR: + __ InvokeBuiltin(Builtins::BIT_OR, JUMP_FUNCTION); + break; + case Token::BIT_AND: + __ InvokeBuiltin(Builtins::BIT_AND, JUMP_FUNCTION); + break; + case Token::BIT_XOR: + __ InvokeBuiltin(Builtins::BIT_XOR, JUMP_FUNCTION); + break; + case Token::SAR: + __ InvokeBuiltin(Builtins::SAR, JUMP_FUNCTION); + break; + case Token::SHL: + __ InvokeBuiltin(Builtins::SHL, JUMP_FUNCTION); + break; + case Token::SHR: + __ InvokeBuiltin(Builtins::SHR, JUMP_FUNCTION); + break; + default: + UNREACHABLE(); + } +} + + +void GenericBinaryOpStub::GenerateLoadArguments(MacroAssembler* masm) { + ASSERT(!HasArgsInRegisters()); + __ movq(rax, Operand(rsp, 1 * kPointerSize)); + __ movq(rdx, Operand(rsp, 2 * kPointerSize)); +} + + +void GenericBinaryOpStub::GenerateReturn(MacroAssembler* masm) { + // If arguments are not passed in registers remove them from the stack before + // returning. + if (!HasArgsInRegisters()) { + __ ret(2 * kPointerSize); // Remove both operands + } else { + __ ret(0); + } +} + + +void GenericBinaryOpStub::GenerateRegisterArgsPush(MacroAssembler* masm) { + ASSERT(HasArgsInRegisters()); + __ pop(rcx); + if (HasArgsReversed()) { + __ push(rax); + __ push(rdx); + } else { + __ push(rdx); + __ push(rax); + } + __ push(rcx); +} + + +void GenericBinaryOpStub::GenerateTypeTransition(MacroAssembler* masm) { + Label get_result; + + // Ensure the operands are on the stack. + if (HasArgsInRegisters()) { + GenerateRegisterArgsPush(masm); + } + + // Left and right arguments are already on stack. + __ pop(rcx); // Save the return address. + + // Push this stub's key. + __ Push(Smi::FromInt(MinorKey())); + + // Although the operation and the type info are encoded into the key, + // the encoding is opaque, so push them too. + __ Push(Smi::FromInt(op_)); + + __ Push(Smi::FromInt(runtime_operands_type_)); + + __ push(rcx); // The return address. + + // Perform patching to an appropriate fast case and return the result. + __ TailCallExternalReference( + ExternalReference(IC_Utility(IC::kBinaryOp_Patch)), + 5, + 1); +} + + +Handle<Code> GetBinaryOpStub(int key, BinaryOpIC::TypeInfo type_info) { + GenericBinaryOpStub stub(key, type_info); + return stub.GetCode(); +} + + +void TranscendentalCacheStub::Generate(MacroAssembler* masm) { + // Input on stack: + // rsp[8]: argument (should be number). + // rsp[0]: return address. + Label runtime_call; + Label runtime_call_clear_stack; + Label input_not_smi; + Label loaded; + // Test that rax is a number. + __ movq(rax, Operand(rsp, kPointerSize)); + __ JumpIfNotSmi(rax, &input_not_smi); + // Input is a smi. Untag and load it onto the FPU stack. + // Then load the bits of the double into rbx. + __ SmiToInteger32(rax, rax); + __ subq(rsp, Immediate(kPointerSize)); + __ cvtlsi2sd(xmm1, rax); + __ movsd(Operand(rsp, 0), xmm1); + __ movq(rbx, xmm1); + __ movq(rdx, xmm1); + __ fld_d(Operand(rsp, 0)); + __ addq(rsp, Immediate(kPointerSize)); + __ jmp(&loaded); + + __ bind(&input_not_smi); + // Check if input is a HeapNumber. + __ Move(rbx, Factory::heap_number_map()); + __ cmpq(rbx, FieldOperand(rax, HeapObject::kMapOffset)); + __ j(not_equal, &runtime_call); + // Input is a HeapNumber. Push it on the FPU stack and load its + // bits into rbx. + __ fld_d(FieldOperand(rax, HeapNumber::kValueOffset)); + __ movq(rbx, FieldOperand(rax, HeapNumber::kValueOffset)); + __ movq(rdx, rbx); + __ bind(&loaded); + // ST[0] == double value + // rbx = bits of double value. + // rdx = also bits of double value. + // Compute hash (h is 32 bits, bits are 64 and the shifts are arithmetic): + // h = h0 = bits ^ (bits >> 32); + // h ^= h >> 16; + // h ^= h >> 8; + // h = h & (cacheSize - 1); + // or h = (h0 ^ (h0 >> 8) ^ (h0 >> 16) ^ (h0 >> 24)) & (cacheSize - 1) + __ sar(rdx, Immediate(32)); + __ xorl(rdx, rbx); + __ movl(rcx, rdx); + __ movl(rax, rdx); + __ movl(rdi, rdx); + __ sarl(rdx, Immediate(8)); + __ sarl(rcx, Immediate(16)); + __ sarl(rax, Immediate(24)); + __ xorl(rcx, rdx); + __ xorl(rax, rdi); + __ xorl(rcx, rax); + ASSERT(IsPowerOf2(TranscendentalCache::kCacheSize)); + __ andl(rcx, Immediate(TranscendentalCache::kCacheSize - 1)); + + // ST[0] == double value. + // rbx = bits of double value. + // rcx = TranscendentalCache::hash(double value). + __ movq(rax, ExternalReference::transcendental_cache_array_address()); + // rax points to cache array. + __ movq(rax, Operand(rax, type_ * sizeof(TranscendentalCache::caches_[0]))); + // rax points to the cache for the type type_. + // If NULL, the cache hasn't been initialized yet, so go through runtime. + __ testq(rax, rax); + __ j(zero, &runtime_call_clear_stack); +#ifdef DEBUG + // Check that the layout of cache elements match expectations. + { // NOLINT - doesn't like a single brace on a line. + TranscendentalCache::Element test_elem[2]; + char* elem_start = reinterpret_cast<char*>(&test_elem[0]); + char* elem2_start = reinterpret_cast<char*>(&test_elem[1]); + char* elem_in0 = reinterpret_cast<char*>(&(test_elem[0].in[0])); + char* elem_in1 = reinterpret_cast<char*>(&(test_elem[0].in[1])); + char* elem_out = reinterpret_cast<char*>(&(test_elem[0].output)); + // Two uint_32's and a pointer per element. + CHECK_EQ(16, static_cast<int>(elem2_start - elem_start)); + CHECK_EQ(0, static_cast<int>(elem_in0 - elem_start)); + CHECK_EQ(kIntSize, static_cast<int>(elem_in1 - elem_start)); + CHECK_EQ(2 * kIntSize, static_cast<int>(elem_out - elem_start)); + } +#endif + // Find the address of the rcx'th entry in the cache, i.e., &rax[rcx*16]. + __ addl(rcx, rcx); + __ lea(rcx, Operand(rax, rcx, times_8, 0)); + // Check if cache matches: Double value is stored in uint32_t[2] array. + Label cache_miss; + __ cmpq(rbx, Operand(rcx, 0)); + __ j(not_equal, &cache_miss); + // Cache hit! + __ movq(rax, Operand(rcx, 2 * kIntSize)); + __ fstp(0); // Clear FPU stack. + __ ret(kPointerSize); + + __ bind(&cache_miss); + // Update cache with new value. + Label nan_result; + GenerateOperation(masm, &nan_result); + __ AllocateHeapNumber(rax, rdi, &runtime_call_clear_stack); + __ movq(Operand(rcx, 0), rbx); + __ movq(Operand(rcx, 2 * kIntSize), rax); + __ fstp_d(FieldOperand(rax, HeapNumber::kValueOffset)); + __ ret(kPointerSize); + + __ bind(&runtime_call_clear_stack); + __ fstp(0); + __ bind(&runtime_call); + __ TailCallExternalReference(ExternalReference(RuntimeFunction()), 1, 1); + + __ bind(&nan_result); + __ fstp(0); // Remove argument from FPU stack. + __ LoadRoot(rax, Heap::kNanValueRootIndex); + __ movq(Operand(rcx, 0), rbx); + __ movq(Operand(rcx, 2 * kIntSize), rax); + __ ret(kPointerSize); +} + + +Runtime::FunctionId TranscendentalCacheStub::RuntimeFunction() { + switch (type_) { + // Add more cases when necessary. + case TranscendentalCache::SIN: return Runtime::kMath_sin; + case TranscendentalCache::COS: return Runtime::kMath_cos; + default: + UNIMPLEMENTED(); + return Runtime::kAbort; + } +} + + +void TranscendentalCacheStub::GenerateOperation(MacroAssembler* masm, + Label* on_nan_result) { + // Registers: + // rbx: Bits of input double. Must be preserved. + // rcx: Pointer to cache entry. Must be preserved. + // st(0): Input double + Label done; + ASSERT(type_ == TranscendentalCache::SIN || + type_ == TranscendentalCache::COS); + // More transcendental types can be added later. + + // Both fsin and fcos require arguments in the range +/-2^63 and + // return NaN for infinities and NaN. They can share all code except + // the actual fsin/fcos operation. + Label in_range; + // If argument is outside the range -2^63..2^63, fsin/cos doesn't + // work. We must reduce it to the appropriate range. + __ movq(rdi, rbx); + // Move exponent and sign bits to low bits. + __ shr(rdi, Immediate(HeapNumber::kMantissaBits)); + // Remove sign bit. + __ andl(rdi, Immediate((1 << HeapNumber::kExponentBits) - 1)); + int supported_exponent_limit = (63 + HeapNumber::kExponentBias); + __ cmpl(rdi, Immediate(supported_exponent_limit)); + __ j(below, &in_range); + // Check for infinity and NaN. Both return NaN for sin. + __ cmpl(rdi, Immediate(0x7ff)); + __ j(equal, on_nan_result); + + // Use fpmod to restrict argument to the range +/-2*PI. + __ fldpi(); + __ fadd(0); + __ fld(1); + // FPU Stack: input, 2*pi, input. + { + Label no_exceptions; + __ fwait(); + __ fnstsw_ax(); + // Clear if Illegal Operand or Zero Division exceptions are set. + __ testl(rax, Immediate(5)); // #IO and #ZD flags of FPU status word. + __ j(zero, &no_exceptions); + __ fnclex(); + __ bind(&no_exceptions); + } + + // Compute st(0) % st(1) + { + Label partial_remainder_loop; + __ bind(&partial_remainder_loop); + __ fprem1(); + __ fwait(); + __ fnstsw_ax(); + __ testl(rax, Immediate(0x400)); // Check C2 bit of FPU status word. + // If C2 is set, computation only has partial result. Loop to + // continue computation. + __ j(not_zero, &partial_remainder_loop); + } + // FPU Stack: input, 2*pi, input % 2*pi + __ fstp(2); + // FPU Stack: input % 2*pi, 2*pi, + __ fstp(0); + // FPU Stack: input % 2*pi + __ bind(&in_range); + switch (type_) { + case TranscendentalCache::SIN: + __ fsin(); + break; + case TranscendentalCache::COS: + __ fcos(); + break; + default: + UNREACHABLE(); + } + __ bind(&done); +} + + +// Get the integer part of a heap number. +// Overwrites the contents of rdi, rbx and rcx. Result cannot be rdi or rbx. +void IntegerConvert(MacroAssembler* masm, + Register result, + Register source) { + // Result may be rcx. If result and source are the same register, source will + // be overwritten. + ASSERT(!result.is(rdi) && !result.is(rbx)); + // TODO(lrn): When type info reaches here, if value is a 32-bit integer, use + // cvttsd2si (32-bit version) directly. + Register double_exponent = rbx; + Register double_value = rdi; + Label done, exponent_63_plus; + // Get double and extract exponent. + __ movq(double_value, FieldOperand(source, HeapNumber::kValueOffset)); + // Clear result preemptively, in case we need to return zero. + __ xorl(result, result); + __ movq(xmm0, double_value); // Save copy in xmm0 in case we need it there. + // Double to remove sign bit, shift exponent down to least significant bits. + // and subtract bias to get the unshifted, unbiased exponent. + __ lea(double_exponent, Operand(double_value, double_value, times_1, 0)); + __ shr(double_exponent, Immediate(64 - HeapNumber::kExponentBits)); + __ subl(double_exponent, Immediate(HeapNumber::kExponentBias)); + // Check whether the exponent is too big for a 63 bit unsigned integer. + __ cmpl(double_exponent, Immediate(63)); + __ j(above_equal, &exponent_63_plus); + // Handle exponent range 0..62. + __ cvttsd2siq(result, xmm0); + __ jmp(&done); + + __ bind(&exponent_63_plus); + // Exponent negative or 63+. + __ cmpl(double_exponent, Immediate(83)); + // If exponent negative or above 83, number contains no significant bits in + // the range 0..2^31, so result is zero, and rcx already holds zero. + __ j(above, &done); + + // Exponent in rage 63..83. + // Mantissa * 2^exponent contains bits in the range 2^0..2^31, namely + // the least significant exponent-52 bits. + + // Negate low bits of mantissa if value is negative. + __ addq(double_value, double_value); // Move sign bit to carry. + __ sbbl(result, result); // And convert carry to -1 in result register. + // if scratch2 is negative, do (scratch2-1)^-1, otherwise (scratch2-0)^0. + __ addl(double_value, result); + // Do xor in opposite directions depending on where we want the result + // (depending on whether result is rcx or not). + + if (result.is(rcx)) { + __ xorl(double_value, result); + // Left shift mantissa by (exponent - mantissabits - 1) to save the + // bits that have positional values below 2^32 (the extra -1 comes from the + // doubling done above to move the sign bit into the carry flag). + __ leal(rcx, Operand(double_exponent, -HeapNumber::kMantissaBits - 1)); + __ shll_cl(double_value); + __ movl(result, double_value); + } else { + // As the then-branch, but move double-value to result before shifting. + __ xorl(result, double_value); + __ leal(rcx, Operand(double_exponent, -HeapNumber::kMantissaBits - 1)); + __ shll_cl(result); + } + + __ bind(&done); +} + + +// Input: rdx, rax are the left and right objects of a bit op. +// Output: rax, rcx are left and right integers for a bit op. +void FloatingPointHelper::LoadNumbersAsIntegers(MacroAssembler* masm) { + // Check float operands. + Label done; + Label rax_is_smi; + Label rax_is_object; + Label rdx_is_object; + + __ JumpIfNotSmi(rdx, &rdx_is_object); + __ SmiToInteger32(rdx, rdx); + __ JumpIfSmi(rax, &rax_is_smi); + + __ bind(&rax_is_object); + IntegerConvert(masm, rcx, rax); // Uses rdi, rcx and rbx. + __ jmp(&done); + + __ bind(&rdx_is_object); + IntegerConvert(masm, rdx, rdx); // Uses rdi, rcx and rbx. + __ JumpIfNotSmi(rax, &rax_is_object); + __ bind(&rax_is_smi); + __ SmiToInteger32(rcx, rax); + + __ bind(&done); + __ movl(rax, rdx); +} + + +// Input: rdx, rax are the left and right objects of a bit op. +// Output: rax, rcx are left and right integers for a bit op. +void FloatingPointHelper::LoadAsIntegers(MacroAssembler* masm, + Label* conversion_failure, + Register heap_number_map) { + // Check float operands. + Label arg1_is_object, check_undefined_arg1; + Label arg2_is_object, check_undefined_arg2; + Label load_arg2, done; + + __ JumpIfNotSmi(rdx, &arg1_is_object); + __ SmiToInteger32(rdx, rdx); + __ jmp(&load_arg2); + + // If the argument is undefined it converts to zero (ECMA-262, section 9.5). + __ bind(&check_undefined_arg1); + __ CompareRoot(rdx, Heap::kUndefinedValueRootIndex); + __ j(not_equal, conversion_failure); + __ movl(rdx, Immediate(0)); + __ jmp(&load_arg2); + + __ bind(&arg1_is_object); + __ cmpq(FieldOperand(rdx, HeapObject::kMapOffset), heap_number_map); + __ j(not_equal, &check_undefined_arg1); + // Get the untagged integer version of the edx heap number in rcx. + IntegerConvert(masm, rdx, rdx); + + // Here rdx has the untagged integer, rax has a Smi or a heap number. + __ bind(&load_arg2); + // Test if arg2 is a Smi. + __ JumpIfNotSmi(rax, &arg2_is_object); + __ SmiToInteger32(rax, rax); + __ movl(rcx, rax); + __ jmp(&done); + + // If the argument is undefined it converts to zero (ECMA-262, section 9.5). + __ bind(&check_undefined_arg2); + __ CompareRoot(rax, Heap::kUndefinedValueRootIndex); + __ j(not_equal, conversion_failure); + __ movl(rcx, Immediate(0)); + __ jmp(&done); + + __ bind(&arg2_is_object); + __ cmpq(FieldOperand(rax, HeapObject::kMapOffset), heap_number_map); + __ j(not_equal, &check_undefined_arg2); + // Get the untagged integer version of the rax heap number in rcx. + IntegerConvert(masm, rcx, rax); + __ bind(&done); + __ movl(rax, rdx); +} + + +void FloatingPointHelper::LoadSSE2SmiOperands(MacroAssembler* masm) { + __ SmiToInteger32(kScratchRegister, rdx); + __ cvtlsi2sd(xmm0, kScratchRegister); + __ SmiToInteger32(kScratchRegister, rax); + __ cvtlsi2sd(xmm1, kScratchRegister); +} + + +void FloatingPointHelper::LoadSSE2NumberOperands(MacroAssembler* masm) { + Label load_smi_rdx, load_nonsmi_rax, load_smi_rax, done; + // Load operand in rdx into xmm0. + __ JumpIfSmi(rdx, &load_smi_rdx); + __ movsd(xmm0, FieldOperand(rdx, HeapNumber::kValueOffset)); + // Load operand in rax into xmm1. + __ JumpIfSmi(rax, &load_smi_rax); + __ bind(&load_nonsmi_rax); + __ movsd(xmm1, FieldOperand(rax, HeapNumber::kValueOffset)); + __ jmp(&done); + + __ bind(&load_smi_rdx); + __ SmiToInteger32(kScratchRegister, rdx); + __ cvtlsi2sd(xmm0, kScratchRegister); + __ JumpIfNotSmi(rax, &load_nonsmi_rax); + + __ bind(&load_smi_rax); + __ SmiToInteger32(kScratchRegister, rax); + __ cvtlsi2sd(xmm1, kScratchRegister); + + __ bind(&done); +} + + +void FloatingPointHelper::LoadSSE2UnknownOperands(MacroAssembler* masm, + Label* not_numbers) { + Label load_smi_rdx, load_nonsmi_rax, load_smi_rax, load_float_rax, done; + // Load operand in rdx into xmm0, or branch to not_numbers. + __ LoadRoot(rcx, Heap::kHeapNumberMapRootIndex); + __ JumpIfSmi(rdx, &load_smi_rdx); + __ cmpq(FieldOperand(rdx, HeapObject::kMapOffset), rcx); + __ j(not_equal, not_numbers); // Argument in rdx is not a number. + __ movsd(xmm0, FieldOperand(rdx, HeapNumber::kValueOffset)); + // Load operand in rax into xmm1, or branch to not_numbers. + __ JumpIfSmi(rax, &load_smi_rax); + + __ bind(&load_nonsmi_rax); + __ cmpq(FieldOperand(rax, HeapObject::kMapOffset), rcx); + __ j(not_equal, not_numbers); + __ movsd(xmm1, FieldOperand(rax, HeapNumber::kValueOffset)); + __ jmp(&done); + + __ bind(&load_smi_rdx); + __ SmiToInteger32(kScratchRegister, rdx); + __ cvtlsi2sd(xmm0, kScratchRegister); + __ JumpIfNotSmi(rax, &load_nonsmi_rax); + + __ bind(&load_smi_rax); + __ SmiToInteger32(kScratchRegister, rax); + __ cvtlsi2sd(xmm1, kScratchRegister); + __ bind(&done); +} + + +void GenericUnaryOpStub::Generate(MacroAssembler* masm) { + Label slow, done; + + if (op_ == Token::SUB) { + // Check whether the value is a smi. + Label try_float; + __ JumpIfNotSmi(rax, &try_float); + + if (negative_zero_ == kIgnoreNegativeZero) { + __ SmiCompare(rax, Smi::FromInt(0)); + __ j(equal, &done); + } + + // Enter runtime system if the value of the smi is zero + // to make sure that we switch between 0 and -0. + // Also enter it if the value of the smi is Smi::kMinValue. + __ SmiNeg(rax, rax, &done); + + // Either zero or Smi::kMinValue, neither of which become a smi when + // negated. + if (negative_zero_ == kStrictNegativeZero) { + __ SmiCompare(rax, Smi::FromInt(0)); + __ j(not_equal, &slow); + __ Move(rax, Factory::minus_zero_value()); + __ jmp(&done); + } else { + __ jmp(&slow); + } + + // Try floating point case. + __ bind(&try_float); + __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset)); + __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex); + __ j(not_equal, &slow); + // Operand is a float, negate its value by flipping sign bit. + __ movq(rdx, FieldOperand(rax, HeapNumber::kValueOffset)); + __ movq(kScratchRegister, Immediate(0x01)); + __ shl(kScratchRegister, Immediate(63)); + __ xor_(rdx, kScratchRegister); // Flip sign. + // rdx is value to store. + if (overwrite_ == UNARY_OVERWRITE) { + __ movq(FieldOperand(rax, HeapNumber::kValueOffset), rdx); + } else { + __ AllocateHeapNumber(rcx, rbx, &slow); + // rcx: allocated 'empty' number + __ movq(FieldOperand(rcx, HeapNumber::kValueOffset), rdx); + __ movq(rax, rcx); + } + } else if (op_ == Token::BIT_NOT) { + // Check if the operand is a heap number. + __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset)); + __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex); + __ j(not_equal, &slow); + + // Convert the heap number in rax to an untagged integer in rcx. + IntegerConvert(masm, rax, rax); + + // Do the bitwise operation and smi tag the result. + __ notl(rax); + __ Integer32ToSmi(rax, rax); + } + + // Return from the stub. + __ bind(&done); + __ StubReturn(1); + + // Handle the slow case by jumping to the JavaScript builtin. + __ bind(&slow); + __ pop(rcx); // pop return address + __ push(rax); + __ push(rcx); // push return address + switch (op_) { + case Token::SUB: + __ InvokeBuiltin(Builtins::UNARY_MINUS, JUMP_FUNCTION); + break; + case Token::BIT_NOT: + __ InvokeBuiltin(Builtins::BIT_NOT, JUMP_FUNCTION); + break; + default: + UNREACHABLE(); + } +} + + +void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) { + // The key is in rdx and the parameter count is in rax. + + // The displacement is used for skipping the frame pointer on the + // stack. It is the offset of the last parameter (if any) relative + // to the frame pointer. + static const int kDisplacement = 1 * kPointerSize; + + // Check that the key is a smi. + Label slow; + __ JumpIfNotSmi(rdx, &slow); + + // Check if the calling frame is an arguments adaptor frame. + Label adaptor; + __ movq(rbx, Operand(rbp, StandardFrameConstants::kCallerFPOffset)); + __ SmiCompare(Operand(rbx, StandardFrameConstants::kContextOffset), + Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)); + __ j(equal, &adaptor); + + // Check index against formal parameters count limit passed in + // through register rax. Use unsigned comparison to get negative + // check for free. + __ cmpq(rdx, rax); + __ j(above_equal, &slow); + + // Read the argument from the stack and return it. + SmiIndex index = masm->SmiToIndex(rax, rax, kPointerSizeLog2); + __ lea(rbx, Operand(rbp, index.reg, index.scale, 0)); + index = masm->SmiToNegativeIndex(rdx, rdx, kPointerSizeLog2); + __ movq(rax, Operand(rbx, index.reg, index.scale, kDisplacement)); + __ Ret(); + + // Arguments adaptor case: Check index against actual arguments + // limit found in the arguments adaptor frame. Use unsigned + // comparison to get negative check for free. + __ bind(&adaptor); + __ movq(rcx, Operand(rbx, ArgumentsAdaptorFrameConstants::kLengthOffset)); + __ cmpq(rdx, rcx); + __ j(above_equal, &slow); + + // Read the argument from the stack and return it. + index = masm->SmiToIndex(rax, rcx, kPointerSizeLog2); + __ lea(rbx, Operand(rbx, index.reg, index.scale, 0)); + index = masm->SmiToNegativeIndex(rdx, rdx, kPointerSizeLog2); + __ movq(rax, Operand(rbx, index.reg, index.scale, kDisplacement)); + __ Ret(); + + // Slow-case: Handle non-smi or out-of-bounds access to arguments + // by calling the runtime system. + __ bind(&slow); + __ pop(rbx); // Return address. + __ push(rdx); + __ push(rbx); + __ TailCallRuntime(Runtime::kGetArgumentsProperty, 1, 1); +} + + +void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* masm) { + // rsp[0] : return address + // rsp[8] : number of parameters + // rsp[16] : receiver displacement + // rsp[24] : function + + // The displacement is used for skipping the return address and the + // frame pointer on the stack. It is the offset of the last + // parameter (if any) relative to the frame pointer. + static const int kDisplacement = 2 * kPointerSize; + + // Check if the calling frame is an arguments adaptor frame. + Label adaptor_frame, try_allocate, runtime; + __ movq(rdx, Operand(rbp, StandardFrameConstants::kCallerFPOffset)); + __ SmiCompare(Operand(rdx, StandardFrameConstants::kContextOffset), + Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)); + __ j(equal, &adaptor_frame); + + // Get the length from the frame. + __ SmiToInteger32(rcx, Operand(rsp, 1 * kPointerSize)); + __ jmp(&try_allocate); + + // Patch the arguments.length and the parameters pointer. + __ bind(&adaptor_frame); + __ SmiToInteger32(rcx, + Operand(rdx, + ArgumentsAdaptorFrameConstants::kLengthOffset)); + // Space on stack must already hold a smi. + __ Integer32ToSmiField(Operand(rsp, 1 * kPointerSize), rcx); + // Do not clobber the length index for the indexing operation since + // it is used compute the size for allocation later. + __ lea(rdx, Operand(rdx, rcx, times_pointer_size, kDisplacement)); + __ movq(Operand(rsp, 2 * kPointerSize), rdx); + + // Try the new space allocation. Start out with computing the size of + // the arguments object and the elements array. + Label add_arguments_object; + __ bind(&try_allocate); + __ testl(rcx, rcx); + __ j(zero, &add_arguments_object); + __ leal(rcx, Operand(rcx, times_pointer_size, FixedArray::kHeaderSize)); + __ bind(&add_arguments_object); + __ addl(rcx, Immediate(Heap::kArgumentsObjectSize)); + + // Do the allocation of both objects in one go. + __ AllocateInNewSpace(rcx, rax, rdx, rbx, &runtime, TAG_OBJECT); + + // Get the arguments boilerplate from the current (global) context. + int offset = Context::SlotOffset(Context::ARGUMENTS_BOILERPLATE_INDEX); + __ movq(rdi, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX))); + __ movq(rdi, FieldOperand(rdi, GlobalObject::kGlobalContextOffset)); + __ movq(rdi, Operand(rdi, offset)); + + // Copy the JS object part. + STATIC_ASSERT(JSObject::kHeaderSize == 3 * kPointerSize); + __ movq(kScratchRegister, FieldOperand(rdi, 0 * kPointerSize)); + __ movq(rdx, FieldOperand(rdi, 1 * kPointerSize)); + __ movq(rbx, FieldOperand(rdi, 2 * kPointerSize)); + __ movq(FieldOperand(rax, 0 * kPointerSize), kScratchRegister); + __ movq(FieldOperand(rax, 1 * kPointerSize), rdx); + __ movq(FieldOperand(rax, 2 * kPointerSize), rbx); + + // Setup the callee in-object property. + ASSERT(Heap::arguments_callee_index == 0); + __ movq(kScratchRegister, Operand(rsp, 3 * kPointerSize)); + __ movq(FieldOperand(rax, JSObject::kHeaderSize), kScratchRegister); + + // Get the length (smi tagged) and set that as an in-object property too. + ASSERT(Heap::arguments_length_index == 1); + __ movq(rcx, Operand(rsp, 1 * kPointerSize)); + __ movq(FieldOperand(rax, JSObject::kHeaderSize + kPointerSize), rcx); + + // If there are no actual arguments, we're done. + Label done; + __ SmiTest(rcx); + __ j(zero, &done); + + // Get the parameters pointer from the stack and untag the length. + __ movq(rdx, Operand(rsp, 2 * kPointerSize)); + + // Setup the elements pointer in the allocated arguments object and + // initialize the header in the elements fixed array. + __ lea(rdi, Operand(rax, Heap::kArgumentsObjectSize)); + __ movq(FieldOperand(rax, JSObject::kElementsOffset), rdi); + __ LoadRoot(kScratchRegister, Heap::kFixedArrayMapRootIndex); + __ movq(FieldOperand(rdi, FixedArray::kMapOffset), kScratchRegister); + __ movq(FieldOperand(rdi, FixedArray::kLengthOffset), rcx); + __ SmiToInteger32(rcx, rcx); // Untag length for the loop below. + + // Copy the fixed array slots. + Label loop; + __ bind(&loop); + __ movq(kScratchRegister, Operand(rdx, -1 * kPointerSize)); // Skip receiver. + __ movq(FieldOperand(rdi, FixedArray::kHeaderSize), kScratchRegister); + __ addq(rdi, Immediate(kPointerSize)); + __ subq(rdx, Immediate(kPointerSize)); + __ decl(rcx); + __ j(not_zero, &loop); + + // Return and remove the on-stack parameters. + __ bind(&done); + __ ret(3 * kPointerSize); + + // Do the runtime call to allocate the arguments object. + __ bind(&runtime); + __ TailCallRuntime(Runtime::kNewArgumentsFast, 3, 1); +} + + +void RegExpExecStub::Generate(MacroAssembler* masm) { + // Just jump directly to runtime if native RegExp is not selected at compile + // time or if regexp entry in generated code is turned off runtime switch or + // at compilation. +#ifdef V8_INTERPRETED_REGEXP + __ TailCallRuntime(Runtime::kRegExpExec, 4, 1); +#else // V8_INTERPRETED_REGEXP + if (!FLAG_regexp_entry_native) { + __ TailCallRuntime(Runtime::kRegExpExec, 4, 1); + return; + } + + // Stack frame on entry. + // esp[0]: return address + // esp[8]: last_match_info (expected JSArray) + // esp[16]: previous index + // esp[24]: subject string + // esp[32]: JSRegExp object + + static const int kLastMatchInfoOffset = 1 * kPointerSize; + static const int kPreviousIndexOffset = 2 * kPointerSize; + static const int kSubjectOffset = 3 * kPointerSize; + static const int kJSRegExpOffset = 4 * kPointerSize; + + Label runtime; + + // Ensure that a RegExp stack is allocated. + ExternalReference address_of_regexp_stack_memory_address = + ExternalReference::address_of_regexp_stack_memory_address(); + ExternalReference address_of_regexp_stack_memory_size = + ExternalReference::address_of_regexp_stack_memory_size(); + __ movq(kScratchRegister, address_of_regexp_stack_memory_size); + __ movq(kScratchRegister, Operand(kScratchRegister, 0)); + __ testq(kScratchRegister, kScratchRegister); + __ j(zero, &runtime); + + + // Check that the first argument is a JSRegExp object. + __ movq(rax, Operand(rsp, kJSRegExpOffset)); + __ JumpIfSmi(rax, &runtime); + __ CmpObjectType(rax, JS_REGEXP_TYPE, kScratchRegister); + __ j(not_equal, &runtime); + // Check that the RegExp has been compiled (data contains a fixed array). + __ movq(rcx, FieldOperand(rax, JSRegExp::kDataOffset)); + if (FLAG_debug_code) { + Condition is_smi = masm->CheckSmi(rcx); + __ Check(NegateCondition(is_smi), + "Unexpected type for RegExp data, FixedArray expected"); + __ CmpObjectType(rcx, FIXED_ARRAY_TYPE, kScratchRegister); + __ Check(equal, "Unexpected type for RegExp data, FixedArray expected"); + } + + // rcx: RegExp data (FixedArray) + // Check the type of the RegExp. Only continue if type is JSRegExp::IRREGEXP. + __ SmiToInteger32(rbx, FieldOperand(rcx, JSRegExp::kDataTagOffset)); + __ cmpl(rbx, Immediate(JSRegExp::IRREGEXP)); + __ j(not_equal, &runtime); + + // rcx: RegExp data (FixedArray) + // Check that the number of captures fit in the static offsets vector buffer. + __ SmiToInteger32(rdx, + FieldOperand(rcx, JSRegExp::kIrregexpCaptureCountOffset)); + // Calculate number of capture registers (number_of_captures + 1) * 2. + __ leal(rdx, Operand(rdx, rdx, times_1, 2)); + // Check that the static offsets vector buffer is large enough. + __ cmpl(rdx, Immediate(OffsetsVector::kStaticOffsetsVectorSize)); + __ j(above, &runtime); + + // rcx: RegExp data (FixedArray) + // rdx: Number of capture registers + // Check that the second argument is a string. + __ movq(rax, Operand(rsp, kSubjectOffset)); + __ JumpIfSmi(rax, &runtime); + Condition is_string = masm->IsObjectStringType(rax, rbx, rbx); + __ j(NegateCondition(is_string), &runtime); + + // rax: Subject string. + // rcx: RegExp data (FixedArray). + // rdx: Number of capture registers. + // Check that the third argument is a positive smi less than the string + // length. A negative value will be greater (unsigned comparison). + __ movq(rbx, Operand(rsp, kPreviousIndexOffset)); + __ JumpIfNotSmi(rbx, &runtime); + __ SmiCompare(rbx, FieldOperand(rax, String::kLengthOffset)); + __ j(above_equal, &runtime); + + // rcx: RegExp data (FixedArray) + // rdx: Number of capture registers + // Check that the fourth object is a JSArray object. + __ movq(rax, Operand(rsp, kLastMatchInfoOffset)); + __ JumpIfSmi(rax, &runtime); + __ CmpObjectType(rax, JS_ARRAY_TYPE, kScratchRegister); + __ j(not_equal, &runtime); + // Check that the JSArray is in fast case. + __ movq(rbx, FieldOperand(rax, JSArray::kElementsOffset)); + __ movq(rax, FieldOperand(rbx, HeapObject::kMapOffset)); + __ Cmp(rax, Factory::fixed_array_map()); + __ j(not_equal, &runtime); + // Check that the last match info has space for the capture registers and the + // additional information. Ensure no overflow in add. + STATIC_ASSERT(FixedArray::kMaxLength < kMaxInt - FixedArray::kLengthOffset); + __ SmiToInteger32(rax, FieldOperand(rbx, FixedArray::kLengthOffset)); + __ addl(rdx, Immediate(RegExpImpl::kLastMatchOverhead)); + __ cmpl(rdx, rax); + __ j(greater, &runtime); + + // rcx: RegExp data (FixedArray) + // Check the representation and encoding of the subject string. + Label seq_ascii_string, seq_two_byte_string, check_code; + __ movq(rax, Operand(rsp, kSubjectOffset)); + __ movq(rbx, FieldOperand(rax, HeapObject::kMapOffset)); + __ movzxbl(rbx, FieldOperand(rbx, Map::kInstanceTypeOffset)); + // First check for flat two byte string. + __ andb(rbx, Immediate( + kIsNotStringMask | kStringRepresentationMask | kStringEncodingMask)); + STATIC_ASSERT((kStringTag | kSeqStringTag | kTwoByteStringTag) == 0); + __ j(zero, &seq_two_byte_string); + // Any other flat string must be a flat ascii string. + __ testb(rbx, Immediate(kIsNotStringMask | kStringRepresentationMask)); + __ j(zero, &seq_ascii_string); + + // Check for flat cons string. + // A flat cons string is a cons string where the second part is the empty + // string. In that case the subject string is just the first part of the cons + // string. Also in this case the first part of the cons string is known to be + // a sequential string or an external string. + STATIC_ASSERT(kExternalStringTag !=0); + STATIC_ASSERT((kConsStringTag & kExternalStringTag) == 0); + __ testb(rbx, Immediate(kIsNotStringMask | kExternalStringTag)); + __ j(not_zero, &runtime); + // String is a cons string. + __ movq(rdx, FieldOperand(rax, ConsString::kSecondOffset)); + __ Cmp(rdx, Factory::empty_string()); + __ j(not_equal, &runtime); + __ movq(rax, FieldOperand(rax, ConsString::kFirstOffset)); + __ movq(rbx, FieldOperand(rax, HeapObject::kMapOffset)); + // String is a cons string with empty second part. + // rax: first part of cons string. + // rbx: map of first part of cons string. + // Is first part a flat two byte string? + __ testb(FieldOperand(rbx, Map::kInstanceTypeOffset), + Immediate(kStringRepresentationMask | kStringEncodingMask)); + STATIC_ASSERT((kSeqStringTag | kTwoByteStringTag) == 0); + __ j(zero, &seq_two_byte_string); + // Any other flat string must be ascii. + __ testb(FieldOperand(rbx, Map::kInstanceTypeOffset), + Immediate(kStringRepresentationMask)); + __ j(not_zero, &runtime); + + __ bind(&seq_ascii_string); + // rax: subject string (sequential ascii) + // rcx: RegExp data (FixedArray) + __ movq(r11, FieldOperand(rcx, JSRegExp::kDataAsciiCodeOffset)); + __ Set(rdi, 1); // Type is ascii. + __ jmp(&check_code); + + __ bind(&seq_two_byte_string); + // rax: subject string (flat two-byte) + // rcx: RegExp data (FixedArray) + __ movq(r11, FieldOperand(rcx, JSRegExp::kDataUC16CodeOffset)); + __ Set(rdi, 0); // Type is two byte. + + __ bind(&check_code); + // Check that the irregexp code has been generated for the actual string + // encoding. If it has, the field contains a code object otherwise it contains + // the hole. + __ CmpObjectType(r11, CODE_TYPE, kScratchRegister); + __ j(not_equal, &runtime); + + // rax: subject string + // rdi: encoding of subject string (1 if ascii, 0 if two_byte); + // r11: code + // Load used arguments before starting to push arguments for call to native + // RegExp code to avoid handling changing stack height. + __ SmiToInteger64(rbx, Operand(rsp, kPreviousIndexOffset)); + + // rax: subject string + // rbx: previous index + // rdi: encoding of subject string (1 if ascii 0 if two_byte); + // r11: code + // All checks done. Now push arguments for native regexp code. + __ IncrementCounter(&Counters::regexp_entry_native, 1); + + // rsi is caller save on Windows and used to pass parameter on Linux. + __ push(rsi); + + static const int kRegExpExecuteArguments = 7; + __ PrepareCallCFunction(kRegExpExecuteArguments); + int argument_slots_on_stack = + masm->ArgumentStackSlotsForCFunctionCall(kRegExpExecuteArguments); + + // Argument 7: Indicate that this is a direct call from JavaScript. + __ movq(Operand(rsp, (argument_slots_on_stack - 1) * kPointerSize), + Immediate(1)); + + // Argument 6: Start (high end) of backtracking stack memory area. + __ movq(kScratchRegister, address_of_regexp_stack_memory_address); + __ movq(r9, Operand(kScratchRegister, 0)); + __ movq(kScratchRegister, address_of_regexp_stack_memory_size); + __ addq(r9, Operand(kScratchRegister, 0)); + // Argument 6 passed in r9 on Linux and on the stack on Windows. +#ifdef _WIN64 + __ movq(Operand(rsp, (argument_slots_on_stack - 2) * kPointerSize), r9); +#endif + + // Argument 5: static offsets vector buffer. + __ movq(r8, ExternalReference::address_of_static_offsets_vector()); + // Argument 5 passed in r8 on Linux and on the stack on Windows. +#ifdef _WIN64 + __ movq(Operand(rsp, (argument_slots_on_stack - 3) * kPointerSize), r8); +#endif + + // First four arguments are passed in registers on both Linux and Windows. +#ifdef _WIN64 + Register arg4 = r9; + Register arg3 = r8; + Register arg2 = rdx; + Register arg1 = rcx; +#else + Register arg4 = rcx; + Register arg3 = rdx; + Register arg2 = rsi; + Register arg1 = rdi; +#endif + + // Keep track on aliasing between argX defined above and the registers used. + // rax: subject string + // rbx: previous index + // rdi: encoding of subject string (1 if ascii 0 if two_byte); + // r11: code + + // Argument 4: End of string data + // Argument 3: Start of string data + Label setup_two_byte, setup_rest; + __ testb(rdi, rdi); + __ j(zero, &setup_two_byte); + __ SmiToInteger32(rdi, FieldOperand(rax, String::kLengthOffset)); + __ lea(arg4, FieldOperand(rax, rdi, times_1, SeqAsciiString::kHeaderSize)); + __ lea(arg3, FieldOperand(rax, rbx, times_1, SeqAsciiString::kHeaderSize)); + __ jmp(&setup_rest); + __ bind(&setup_two_byte); + __ SmiToInteger32(rdi, FieldOperand(rax, String::kLengthOffset)); + __ lea(arg4, FieldOperand(rax, rdi, times_2, SeqTwoByteString::kHeaderSize)); + __ lea(arg3, FieldOperand(rax, rbx, times_2, SeqTwoByteString::kHeaderSize)); + + __ bind(&setup_rest); + // Argument 2: Previous index. + __ movq(arg2, rbx); + + // Argument 1: Subject string. + __ movq(arg1, rax); + + // Locate the code entry and call it. + __ addq(r11, Immediate(Code::kHeaderSize - kHeapObjectTag)); + __ CallCFunction(r11, kRegExpExecuteArguments); + + // rsi is caller save, as it is used to pass parameter. + __ pop(rsi); + + // Check the result. + Label success; + __ cmpl(rax, Immediate(NativeRegExpMacroAssembler::SUCCESS)); + __ j(equal, &success); + Label failure; + __ cmpl(rax, Immediate(NativeRegExpMacroAssembler::FAILURE)); + __ j(equal, &failure); + __ cmpl(rax, Immediate(NativeRegExpMacroAssembler::EXCEPTION)); + // If not exception it can only be retry. Handle that in the runtime system. + __ j(not_equal, &runtime); + // Result must now be exception. If there is no pending exception already a + // stack overflow (on the backtrack stack) was detected in RegExp code but + // haven't created the exception yet. Handle that in the runtime system. + // TODO(592): Rerunning the RegExp to get the stack overflow exception. + ExternalReference pending_exception_address(Top::k_pending_exception_address); + __ movq(kScratchRegister, pending_exception_address); + __ Cmp(kScratchRegister, Factory::the_hole_value()); + __ j(equal, &runtime); + __ bind(&failure); + // For failure and exception return null. + __ Move(rax, Factory::null_value()); + __ ret(4 * kPointerSize); + + // Load RegExp data. + __ bind(&success); + __ movq(rax, Operand(rsp, kJSRegExpOffset)); + __ movq(rcx, FieldOperand(rax, JSRegExp::kDataOffset)); + __ SmiToInteger32(rax, + FieldOperand(rcx, JSRegExp::kIrregexpCaptureCountOffset)); + // Calculate number of capture registers (number_of_captures + 1) * 2. + __ leal(rdx, Operand(rax, rax, times_1, 2)); + + // rdx: Number of capture registers + // Load last_match_info which is still known to be a fast case JSArray. + __ movq(rax, Operand(rsp, kLastMatchInfoOffset)); + __ movq(rbx, FieldOperand(rax, JSArray::kElementsOffset)); + + // rbx: last_match_info backing store (FixedArray) + // rdx: number of capture registers + // Store the capture count. + __ Integer32ToSmi(kScratchRegister, rdx); + __ movq(FieldOperand(rbx, RegExpImpl::kLastCaptureCountOffset), + kScratchRegister); + // Store last subject and last input. + __ movq(rax, Operand(rsp, kSubjectOffset)); + __ movq(FieldOperand(rbx, RegExpImpl::kLastSubjectOffset), rax); + __ movq(rcx, rbx); + __ RecordWrite(rcx, RegExpImpl::kLastSubjectOffset, rax, rdi); + __ movq(rax, Operand(rsp, kSubjectOffset)); + __ movq(FieldOperand(rbx, RegExpImpl::kLastInputOffset), rax); + __ movq(rcx, rbx); + __ RecordWrite(rcx, RegExpImpl::kLastInputOffset, rax, rdi); + + // Get the static offsets vector filled by the native regexp code. + __ movq(rcx, ExternalReference::address_of_static_offsets_vector()); + + // rbx: last_match_info backing store (FixedArray) + // rcx: offsets vector + // rdx: number of capture registers + Label next_capture, done; + // Capture register counter starts from number of capture registers and + // counts down until wraping after zero. + __ bind(&next_capture); + __ subq(rdx, Immediate(1)); + __ j(negative, &done); + // Read the value from the static offsets vector buffer and make it a smi. + __ movl(rdi, Operand(rcx, rdx, times_int_size, 0)); + __ Integer32ToSmi(rdi, rdi, &runtime); + // Store the smi value in the last match info. + __ movq(FieldOperand(rbx, + rdx, + times_pointer_size, + RegExpImpl::kFirstCaptureOffset), + rdi); + __ jmp(&next_capture); + __ bind(&done); + + // Return last match info. + __ movq(rax, Operand(rsp, kLastMatchInfoOffset)); + __ ret(4 * kPointerSize); + + // Do the runtime call to execute the regexp. + __ bind(&runtime); + __ TailCallRuntime(Runtime::kRegExpExec, 4, 1); +#endif // V8_INTERPRETED_REGEXP +} + + +void NumberToStringStub::GenerateLookupNumberStringCache(MacroAssembler* masm, + Register object, + Register result, + Register scratch1, + Register scratch2, + bool object_is_smi, + Label* not_found) { + // Use of registers. Register result is used as a temporary. + Register number_string_cache = result; + Register mask = scratch1; + Register scratch = scratch2; + + // Load the number string cache. + __ LoadRoot(number_string_cache, Heap::kNumberStringCacheRootIndex); + + // Make the hash mask from the length of the number string cache. It + // contains two elements (number and string) for each cache entry. + __ SmiToInteger32( + mask, FieldOperand(number_string_cache, FixedArray::kLengthOffset)); + __ shrl(mask, Immediate(1)); + __ subq(mask, Immediate(1)); // Make mask. + + // Calculate the entry in the number string cache. The hash value in the + // number string cache for smis is just the smi value, and the hash for + // doubles is the xor of the upper and lower words. See + // Heap::GetNumberStringCache. + Label is_smi; + Label load_result_from_cache; + if (!object_is_smi) { + __ JumpIfSmi(object, &is_smi); + __ CheckMap(object, Factory::heap_number_map(), not_found, true); + + STATIC_ASSERT(8 == kDoubleSize); + __ movl(scratch, FieldOperand(object, HeapNumber::kValueOffset + 4)); + __ xor_(scratch, FieldOperand(object, HeapNumber::kValueOffset)); + GenerateConvertHashCodeToIndex(masm, scratch, mask); + + Register index = scratch; + Register probe = mask; + __ movq(probe, + FieldOperand(number_string_cache, + index, + times_1, + FixedArray::kHeaderSize)); + __ JumpIfSmi(probe, not_found); + ASSERT(CpuFeatures::IsSupported(SSE2)); + CpuFeatures::Scope fscope(SSE2); + __ movsd(xmm0, FieldOperand(object, HeapNumber::kValueOffset)); + __ movsd(xmm1, FieldOperand(probe, HeapNumber::kValueOffset)); + __ ucomisd(xmm0, xmm1); + __ j(parity_even, not_found); // Bail out if NaN is involved. + __ j(not_equal, not_found); // The cache did not contain this value. + __ jmp(&load_result_from_cache); + } + + __ bind(&is_smi); + __ SmiToInteger32(scratch, object); + GenerateConvertHashCodeToIndex(masm, scratch, mask); + + Register index = scratch; + // Check if the entry is the smi we are looking for. + __ cmpq(object, + FieldOperand(number_string_cache, + index, + times_1, + FixedArray::kHeaderSize)); + __ j(not_equal, not_found); + + // Get the result from the cache. + __ bind(&load_result_from_cache); + __ movq(result, + FieldOperand(number_string_cache, + index, + times_1, + FixedArray::kHeaderSize + kPointerSize)); + __ IncrementCounter(&Counters::number_to_string_native, 1); +} + + +void NumberToStringStub::GenerateConvertHashCodeToIndex(MacroAssembler* masm, + Register hash, + Register mask) { + __ and_(hash, mask); + // Each entry in string cache consists of two pointer sized fields, + // but times_twice_pointer_size (multiplication by 16) scale factor + // is not supported by addrmode on x64 platform. + // So we have to premultiply entry index before lookup. + __ shl(hash, Immediate(kPointerSizeLog2 + 1)); +} + + +void NumberToStringStub::Generate(MacroAssembler* masm) { + Label runtime; + + __ movq(rbx, Operand(rsp, kPointerSize)); + + // Generate code to lookup number in the number string cache. + GenerateLookupNumberStringCache(masm, rbx, rax, r8, r9, false, &runtime); + __ ret(1 * kPointerSize); + + __ bind(&runtime); + // Handle number to string in the runtime system if not found in the cache. + __ TailCallRuntime(Runtime::kNumberToStringSkipCache, 1, 1); +} + + +static int NegativeComparisonResult(Condition cc) { + ASSERT(cc != equal); + ASSERT((cc == less) || (cc == less_equal) + || (cc == greater) || (cc == greater_equal)); + return (cc == greater || cc == greater_equal) ? LESS : GREATER; +} + + +void CompareStub::Generate(MacroAssembler* masm) { + ASSERT(lhs_.is(no_reg) && rhs_.is(no_reg)); + + Label check_unequal_objects, done; + // The compare stub returns a positive, negative, or zero 64-bit integer + // value in rax, corresponding to result of comparing the two inputs. + // NOTICE! This code is only reached after a smi-fast-case check, so + // it is certain that at least one operand isn't a smi. + + // Two identical objects are equal unless they are both NaN or undefined. + { + Label not_identical; + __ cmpq(rax, rdx); + __ j(not_equal, ¬_identical); + + if (cc_ != equal) { + // Check for undefined. undefined OP undefined is false even though + // undefined == undefined. + Label check_for_nan; + __ CompareRoot(rdx, Heap::kUndefinedValueRootIndex); + __ j(not_equal, &check_for_nan); + __ Set(rax, NegativeComparisonResult(cc_)); + __ ret(0); + __ bind(&check_for_nan); + } + + // Test for NaN. Sadly, we can't just compare to Factory::nan_value(), + // so we do the second best thing - test it ourselves. + // Note: if cc_ != equal, never_nan_nan_ is not used. + // We cannot set rax to EQUAL until just before return because + // rax must be unchanged on jump to not_identical. + + if (never_nan_nan_ && (cc_ == equal)) { + __ Set(rax, EQUAL); + __ ret(0); + } else { + Label heap_number; + // If it's not a heap number, then return equal for (in)equality operator. + __ Cmp(FieldOperand(rdx, HeapObject::kMapOffset), + Factory::heap_number_map()); + __ j(equal, &heap_number); + if (cc_ != equal) { + // Call runtime on identical JSObjects. Otherwise return equal. + __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rcx); + __ j(above_equal, ¬_identical); + } + __ Set(rax, EQUAL); + __ ret(0); + + __ bind(&heap_number); + // It is a heap number, so return equal if it's not NaN. + // For NaN, return 1 for every condition except greater and + // greater-equal. Return -1 for them, so the comparison yields + // false for all conditions except not-equal. + __ Set(rax, EQUAL); + __ movsd(xmm0, FieldOperand(rdx, HeapNumber::kValueOffset)); + __ ucomisd(xmm0, xmm0); + __ setcc(parity_even, rax); + // rax is 0 for equal non-NaN heapnumbers, 1 for NaNs. + if (cc_ == greater_equal || cc_ == greater) { + __ neg(rax); + } + __ ret(0); + } + + __ bind(¬_identical); + } + + if (cc_ == equal) { // Both strict and non-strict. + Label slow; // Fallthrough label. + + // If we're doing a strict equality comparison, we don't have to do + // type conversion, so we generate code to do fast comparison for objects + // and oddballs. Non-smi numbers and strings still go through the usual + // slow-case code. + if (strict_) { + // If either is a Smi (we know that not both are), then they can only + // be equal if the other is a HeapNumber. If so, use the slow case. + { + Label not_smis; + __ SelectNonSmi(rbx, rax, rdx, ¬_smis); + + // Check if the non-smi operand is a heap number. + __ Cmp(FieldOperand(rbx, HeapObject::kMapOffset), + Factory::heap_number_map()); + // If heap number, handle it in the slow case. + __ j(equal, &slow); + // Return non-equal. ebx (the lower half of rbx) is not zero. + __ movq(rax, rbx); + __ ret(0); + + __ bind(¬_smis); + } + + // If either operand is a JSObject or an oddball value, then they are not + // equal since their pointers are different + // There is no test for undetectability in strict equality. + + // If the first object is a JS object, we have done pointer comparison. + STATIC_ASSERT(LAST_TYPE == JS_FUNCTION_TYPE); + Label first_non_object; + __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rcx); + __ j(below, &first_non_object); + // Return non-zero (eax (not rax) is not zero) + Label return_not_equal; + STATIC_ASSERT(kHeapObjectTag != 0); + __ bind(&return_not_equal); + __ ret(0); + + __ bind(&first_non_object); + // Check for oddballs: true, false, null, undefined. + __ CmpInstanceType(rcx, ODDBALL_TYPE); + __ j(equal, &return_not_equal); + + __ CmpObjectType(rdx, FIRST_JS_OBJECT_TYPE, rcx); + __ j(above_equal, &return_not_equal); + + // Check for oddballs: true, false, null, undefined. + __ CmpInstanceType(rcx, ODDBALL_TYPE); + __ j(equal, &return_not_equal); + + // Fall through to the general case. + } + __ bind(&slow); + } + + // Generate the number comparison code. + if (include_number_compare_) { + Label non_number_comparison; + Label unordered; + FloatingPointHelper::LoadSSE2UnknownOperands(masm, &non_number_comparison); + __ xorl(rax, rax); + __ xorl(rcx, rcx); + __ ucomisd(xmm0, xmm1); + + // Don't base result on EFLAGS when a NaN is involved. + __ j(parity_even, &unordered); + // Return a result of -1, 0, or 1, based on EFLAGS. + __ setcc(above, rax); + __ setcc(below, rcx); + __ subq(rax, rcx); + __ ret(0); + + // If one of the numbers was NaN, then the result is always false. + // The cc is never not-equal. + __ bind(&unordered); + ASSERT(cc_ != not_equal); + if (cc_ == less || cc_ == less_equal) { + __ Set(rax, 1); + } else { + __ Set(rax, -1); + } + __ ret(0); + + // The number comparison code did not provide a valid result. + __ bind(&non_number_comparison); + } + + // Fast negative check for symbol-to-symbol equality. + Label check_for_strings; + if (cc_ == equal) { + BranchIfNonSymbol(masm, &check_for_strings, rax, kScratchRegister); + BranchIfNonSymbol(masm, &check_for_strings, rdx, kScratchRegister); + + // We've already checked for object identity, so if both operands + // are symbols they aren't equal. Register eax (not rax) already holds a + // non-zero value, which indicates not equal, so just return. + __ ret(0); + } + + __ bind(&check_for_strings); + + __ JumpIfNotBothSequentialAsciiStrings( + rdx, rax, rcx, rbx, &check_unequal_objects); + + // Inline comparison of ascii strings. + StringCompareStub::GenerateCompareFlatAsciiStrings(masm, + rdx, + rax, + rcx, + rbx, + rdi, + r8); + +#ifdef DEBUG + __ Abort("Unexpected fall-through from string comparison"); +#endif + + __ bind(&check_unequal_objects); + if (cc_ == equal && !strict_) { + // Not strict equality. Objects are unequal if + // they are both JSObjects and not undetectable, + // and their pointers are different. + Label not_both_objects, return_unequal; + // At most one is a smi, so we can test for smi by adding the two. + // A smi plus a heap object has the low bit set, a heap object plus + // a heap object has the low bit clear. + STATIC_ASSERT(kSmiTag == 0); + STATIC_ASSERT(kSmiTagMask == 1); + __ lea(rcx, Operand(rax, rdx, times_1, 0)); + __ testb(rcx, Immediate(kSmiTagMask)); + __ j(not_zero, ¬_both_objects); + __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rbx); + __ j(below, ¬_both_objects); + __ CmpObjectType(rdx, FIRST_JS_OBJECT_TYPE, rcx); + __ j(below, ¬_both_objects); + __ testb(FieldOperand(rbx, Map::kBitFieldOffset), + Immediate(1 << Map::kIsUndetectable)); + __ j(zero, &return_unequal); + __ testb(FieldOperand(rcx, Map::kBitFieldOffset), + Immediate(1 << Map::kIsUndetectable)); + __ j(zero, &return_unequal); + // The objects are both undetectable, so they both compare as the value + // undefined, and are equal. + __ Set(rax, EQUAL); + __ bind(&return_unequal); + // Return non-equal by returning the non-zero object pointer in eax, + // or return equal if we fell through to here. + __ ret(0); + __ bind(¬_both_objects); + } + + // Push arguments below the return address to prepare jump to builtin. + __ pop(rcx); + __ push(rdx); + __ push(rax); + + // Figure out which native to call and setup the arguments. + Builtins::JavaScript builtin; + if (cc_ == equal) { + builtin = strict_ ? Builtins::STRICT_EQUALS : Builtins::EQUALS; + } else { + builtin = Builtins::COMPARE; + __ Push(Smi::FromInt(NegativeComparisonResult(cc_))); + } + + // Restore return address on the stack. + __ push(rcx); + + // Call the native; it returns -1 (less), 0 (equal), or 1 (greater) + // tagged as a small integer. + __ InvokeBuiltin(builtin, JUMP_FUNCTION); +} + + +void CompareStub::BranchIfNonSymbol(MacroAssembler* masm, + Label* label, + Register object, + Register scratch) { + __ JumpIfSmi(object, label); + __ movq(scratch, FieldOperand(object, HeapObject::kMapOffset)); + __ movzxbq(scratch, + FieldOperand(scratch, Map::kInstanceTypeOffset)); + // Ensure that no non-strings have the symbol bit set. + STATIC_ASSERT(LAST_TYPE < kNotStringTag + kIsSymbolMask); + STATIC_ASSERT(kSymbolTag != 0); + __ testb(scratch, Immediate(kIsSymbolMask)); + __ j(zero, label); +} + + +void StackCheckStub::Generate(MacroAssembler* masm) { + // Because builtins always remove the receiver from the stack, we + // have to fake one to avoid underflowing the stack. The receiver + // must be inserted below the return address on the stack so we + // temporarily store that in a register. + __ pop(rax); + __ Push(Smi::FromInt(0)); + __ push(rax); + + // Do tail-call to runtime routine. + __ TailCallRuntime(Runtime::kStackGuard, 1, 1); +} + + +void CallFunctionStub::Generate(MacroAssembler* masm) { + Label slow; + + // If the receiver might be a value (string, number or boolean) check for this + // and box it if it is. + if (ReceiverMightBeValue()) { + // Get the receiver from the stack. + // +1 ~ return address + Label receiver_is_value, receiver_is_js_object; + __ movq(rax, Operand(rsp, (argc_ + 1) * kPointerSize)); + + // Check if receiver is a smi (which is a number value). + __ JumpIfSmi(rax, &receiver_is_value); + + // Check if the receiver is a valid JS object. + __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rdi); + __ j(above_equal, &receiver_is_js_object); + + // Call the runtime to box the value. + __ bind(&receiver_is_value); + __ EnterInternalFrame(); + __ push(rax); + __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION); + __ LeaveInternalFrame(); + __ movq(Operand(rsp, (argc_ + 1) * kPointerSize), rax); + + __ bind(&receiver_is_js_object); + } + + // Get the function to call from the stack. + // +2 ~ receiver, return address + __ movq(rdi, Operand(rsp, (argc_ + 2) * kPointerSize)); + + // Check that the function really is a JavaScript function. + __ JumpIfSmi(rdi, &slow); + // Goto slow case if we do not have a function. + __ CmpObjectType(rdi, JS_FUNCTION_TYPE, rcx); + __ j(not_equal, &slow); + + // Fast-case: Just invoke the function. + ParameterCount actual(argc_); + __ InvokeFunction(rdi, actual, JUMP_FUNCTION); + + // Slow-case: Non-function called. + __ bind(&slow); + // CALL_NON_FUNCTION expects the non-function callee as receiver (instead + // of the original receiver from the call site). + __ movq(Operand(rsp, (argc_ + 1) * kPointerSize), rdi); + __ Set(rax, argc_); + __ Set(rbx, 0); + __ GetBuiltinEntry(rdx, Builtins::CALL_NON_FUNCTION); + Handle<Code> adaptor(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline)); + __ Jump(adaptor, RelocInfo::CODE_TARGET); +} + + +void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) { + // Check that stack should contain next handler, frame pointer, state and + // return address in that order. + STATIC_ASSERT(StackHandlerConstants::kFPOffset + kPointerSize == + StackHandlerConstants::kStateOffset); + STATIC_ASSERT(StackHandlerConstants::kStateOffset + kPointerSize == + StackHandlerConstants::kPCOffset); + + ExternalReference handler_address(Top::k_handler_address); + __ movq(kScratchRegister, handler_address); + __ movq(rsp, Operand(kScratchRegister, 0)); + // get next in chain + __ pop(rcx); + __ movq(Operand(kScratchRegister, 0), rcx); + __ pop(rbp); // pop frame pointer + __ pop(rdx); // remove state + + // Before returning we restore the context from the frame pointer if not NULL. + // The frame pointer is NULL in the exception handler of a JS entry frame. + __ xor_(rsi, rsi); // tentatively set context pointer to NULL + Label skip; + __ cmpq(rbp, Immediate(0)); + __ j(equal, &skip); + __ movq(rsi, Operand(rbp, StandardFrameConstants::kContextOffset)); + __ bind(&skip); + __ ret(0); +} + + +void ApiGetterEntryStub::Generate(MacroAssembler* masm) { + Label empty_result; + Label prologue; + Label promote_scheduled_exception; + __ EnterApiExitFrame(kStackSpace, 0); + ASSERT_EQ(kArgc, 4); +#ifdef _WIN64 + // All the parameters should be set up by a caller. +#else + // Set 1st parameter register with property name. + __ movq(rsi, rdx); + // Second parameter register rdi should be set with pointer to AccessorInfo + // by a caller. +#endif + // Call the api function! + __ movq(rax, + reinterpret_cast<int64_t>(fun()->address()), + RelocInfo::RUNTIME_ENTRY); + __ call(rax); + // Check if the function scheduled an exception. + ExternalReference scheduled_exception_address = + ExternalReference::scheduled_exception_address(); + __ movq(rsi, scheduled_exception_address); + __ Cmp(Operand(rsi, 0), Factory::the_hole_value()); + __ j(not_equal, &promote_scheduled_exception); +#ifdef _WIN64 + // rax keeps a pointer to v8::Handle, unpack it. + __ movq(rax, Operand(rax, 0)); +#endif + // Check if the result handle holds 0. + __ testq(rax, rax); + __ j(zero, &empty_result); + // It was non-zero. Dereference to get the result value. + __ movq(rax, Operand(rax, 0)); + __ bind(&prologue); + __ LeaveExitFrame(); + __ ret(0); + __ bind(&promote_scheduled_exception); + __ TailCallRuntime(Runtime::kPromoteScheduledException, 0, 1); + __ bind(&empty_result); + // It was zero; the result is undefined. + __ Move(rax, Factory::undefined_value()); + __ jmp(&prologue); +} + + +void CEntryStub::GenerateCore(MacroAssembler* masm, + Label* throw_normal_exception, + Label* throw_termination_exception, + Label* throw_out_of_memory_exception, + bool do_gc, + bool always_allocate_scope, + int /* alignment_skew */) { + // rax: result parameter for PerformGC, if any. + // rbx: pointer to C function (C callee-saved). + // rbp: frame pointer (restored after C call). + // rsp: stack pointer (restored after C call). + // r14: number of arguments including receiver (C callee-saved). + // r12: pointer to the first argument (C callee-saved). + // This pointer is reused in LeaveExitFrame(), so it is stored in a + // callee-saved register. + + // Simple results returned in rax (both AMD64 and Win64 calling conventions). + // Complex results must be written to address passed as first argument. + // AMD64 calling convention: a struct of two pointers in rax+rdx + + // Check stack alignment. + if (FLAG_debug_code) { + __ CheckStackAlignment(); + } + + if (do_gc) { + // Pass failure code returned from last attempt as first argument to + // PerformGC. No need to use PrepareCallCFunction/CallCFunction here as the + // stack is known to be aligned. This function takes one argument which is + // passed in register. +#ifdef _WIN64 + __ movq(rcx, rax); +#else // _WIN64 + __ movq(rdi, rax); +#endif + __ movq(kScratchRegister, + FUNCTION_ADDR(Runtime::PerformGC), + RelocInfo::RUNTIME_ENTRY); + __ call(kScratchRegister); + } + + ExternalReference scope_depth = + ExternalReference::heap_always_allocate_scope_depth(); + if (always_allocate_scope) { + __ movq(kScratchRegister, scope_depth); + __ incl(Operand(kScratchRegister, 0)); + } + + // Call C function. +#ifdef _WIN64 + // Windows 64-bit ABI passes arguments in rcx, rdx, r8, r9 + // Store Arguments object on stack, below the 4 WIN64 ABI parameter slots. + __ movq(Operand(rsp, 4 * kPointerSize), r14); // argc. + __ movq(Operand(rsp, 5 * kPointerSize), r12); // argv. + if (result_size_ < 2) { + // Pass a pointer to the Arguments object as the first argument. + // Return result in single register (rax). + __ lea(rcx, Operand(rsp, 4 * kPointerSize)); + } else { + ASSERT_EQ(2, result_size_); + // Pass a pointer to the result location as the first argument. + __ lea(rcx, Operand(rsp, 6 * kPointerSize)); + // Pass a pointer to the Arguments object as the second argument. + __ lea(rdx, Operand(rsp, 4 * kPointerSize)); + } + +#else // _WIN64 + // GCC passes arguments in rdi, rsi, rdx, rcx, r8, r9. + __ movq(rdi, r14); // argc. + __ movq(rsi, r12); // argv. +#endif + __ call(rbx); + // Result is in rax - do not destroy this register! + + if (always_allocate_scope) { + __ movq(kScratchRegister, scope_depth); + __ decl(Operand(kScratchRegister, 0)); + } + + // Check for failure result. + Label failure_returned; + STATIC_ASSERT(((kFailureTag + 1) & kFailureTagMask) == 0); +#ifdef _WIN64 + // If return value is on the stack, pop it to registers. + if (result_size_ > 1) { + ASSERT_EQ(2, result_size_); + // Read result values stored on stack. Result is stored + // above the four argument mirror slots and the two + // Arguments object slots. + __ movq(rax, Operand(rsp, 6 * kPointerSize)); + __ movq(rdx, Operand(rsp, 7 * kPointerSize)); + } +#endif + __ lea(rcx, Operand(rax, 1)); + // Lower 2 bits of rcx are 0 iff rax has failure tag. + __ testl(rcx, Immediate(kFailureTagMask)); + __ j(zero, &failure_returned); + + // Exit the JavaScript to C++ exit frame. + __ LeaveExitFrame(result_size_); + __ ret(0); + + // Handling of failure. + __ bind(&failure_returned); + + Label retry; + // If the returned exception is RETRY_AFTER_GC continue at retry label + STATIC_ASSERT(Failure::RETRY_AFTER_GC == 0); + __ testl(rax, Immediate(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize)); + __ j(zero, &retry); + + // Special handling of out of memory exceptions. + __ movq(kScratchRegister, Failure::OutOfMemoryException(), RelocInfo::NONE); + __ cmpq(rax, kScratchRegister); + __ j(equal, throw_out_of_memory_exception); + + // Retrieve the pending exception and clear the variable. + ExternalReference pending_exception_address(Top::k_pending_exception_address); + __ movq(kScratchRegister, pending_exception_address); + __ movq(rax, Operand(kScratchRegister, 0)); + __ movq(rdx, ExternalReference::the_hole_value_location()); + __ movq(rdx, Operand(rdx, 0)); + __ movq(Operand(kScratchRegister, 0), rdx); + + // Special handling of termination exceptions which are uncatchable + // by javascript code. + __ CompareRoot(rax, Heap::kTerminationExceptionRootIndex); + __ j(equal, throw_termination_exception); + + // Handle normal exception. + __ jmp(throw_normal_exception); + + // Retry. + __ bind(&retry); +} + + +void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm, + UncatchableExceptionType type) { + // Fetch top stack handler. + ExternalReference handler_address(Top::k_handler_address); + __ movq(kScratchRegister, handler_address); + __ movq(rsp, Operand(kScratchRegister, 0)); + + // Unwind the handlers until the ENTRY handler is found. + Label loop, done; + __ bind(&loop); + // Load the type of the current stack handler. + const int kStateOffset = StackHandlerConstants::kStateOffset; + __ cmpq(Operand(rsp, kStateOffset), Immediate(StackHandler::ENTRY)); + __ j(equal, &done); + // Fetch the next handler in the list. + const int kNextOffset = StackHandlerConstants::kNextOffset; + __ movq(rsp, Operand(rsp, kNextOffset)); + __ jmp(&loop); + __ bind(&done); + + // Set the top handler address to next handler past the current ENTRY handler. + __ movq(kScratchRegister, handler_address); + __ pop(Operand(kScratchRegister, 0)); + + if (type == OUT_OF_MEMORY) { + // Set external caught exception to false. + ExternalReference external_caught(Top::k_external_caught_exception_address); + __ movq(rax, Immediate(false)); + __ store_rax(external_caught); + + // Set pending exception and rax to out of memory exception. + ExternalReference pending_exception(Top::k_pending_exception_address); + __ movq(rax, Failure::OutOfMemoryException(), RelocInfo::NONE); + __ store_rax(pending_exception); + } + + // Clear the context pointer. + __ xor_(rsi, rsi); + + // Restore registers from handler. + STATIC_ASSERT(StackHandlerConstants::kNextOffset + kPointerSize == + StackHandlerConstants::kFPOffset); + __ pop(rbp); // FP + STATIC_ASSERT(StackHandlerConstants::kFPOffset + kPointerSize == + StackHandlerConstants::kStateOffset); + __ pop(rdx); // State + + STATIC_ASSERT(StackHandlerConstants::kStateOffset + kPointerSize == + StackHandlerConstants::kPCOffset); + __ ret(0); +} + + +void CEntryStub::Generate(MacroAssembler* masm) { + // rax: number of arguments including receiver + // rbx: pointer to C function (C callee-saved) + // rbp: frame pointer of calling JS frame (restored after C call) + // rsp: stack pointer (restored after C call) + // rsi: current context (restored) + + // NOTE: Invocations of builtins may return failure objects + // instead of a proper result. The builtin entry handles + // this by performing a garbage collection and retrying the + // builtin once. + + // Enter the exit frame that transitions from JavaScript to C++. + __ EnterExitFrame(result_size_); + + // rax: Holds the context at this point, but should not be used. + // On entry to code generated by GenerateCore, it must hold + // a failure result if the collect_garbage argument to GenerateCore + // is true. This failure result can be the result of code + // generated by a previous call to GenerateCore. The value + // of rax is then passed to Runtime::PerformGC. + // rbx: pointer to builtin function (C callee-saved). + // rbp: frame pointer of exit frame (restored after C call). + // rsp: stack pointer (restored after C call). + // r14: number of arguments including receiver (C callee-saved). + // r12: argv pointer (C callee-saved). + + Label throw_normal_exception; + Label throw_termination_exception; + Label throw_out_of_memory_exception; + + // Call into the runtime system. + GenerateCore(masm, + &throw_normal_exception, + &throw_termination_exception, + &throw_out_of_memory_exception, + false, + false); + + // Do space-specific GC and retry runtime call. + GenerateCore(masm, + &throw_normal_exception, + &throw_termination_exception, + &throw_out_of_memory_exception, + true, + false); + + // Do full GC and retry runtime call one final time. + Failure* failure = Failure::InternalError(); + __ movq(rax, failure, RelocInfo::NONE); + GenerateCore(masm, + &throw_normal_exception, + &throw_termination_exception, + &throw_out_of_memory_exception, + true, + true); + + __ bind(&throw_out_of_memory_exception); + GenerateThrowUncatchable(masm, OUT_OF_MEMORY); + + __ bind(&throw_termination_exception); + GenerateThrowUncatchable(masm, TERMINATION); + + __ bind(&throw_normal_exception); + GenerateThrowTOS(masm); +} + + +void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) { + Label invoke, exit; +#ifdef ENABLE_LOGGING_AND_PROFILING + Label not_outermost_js, not_outermost_js_2; +#endif + + // Setup frame. + __ push(rbp); + __ movq(rbp, rsp); + + // Push the stack frame type marker twice. + int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY; + // Scratch register is neither callee-save, nor an argument register on any + // platform. It's free to use at this point. + // Cannot use smi-register for loading yet. + __ movq(kScratchRegister, + reinterpret_cast<uint64_t>(Smi::FromInt(marker)), + RelocInfo::NONE); + __ push(kScratchRegister); // context slot + __ push(kScratchRegister); // function slot + // Save callee-saved registers (X64/Win64 calling conventions). + __ push(r12); + __ push(r13); + __ push(r14); + __ push(r15); +#ifdef _WIN64 + __ push(rdi); // Only callee save in Win64 ABI, argument in AMD64 ABI. + __ push(rsi); // Only callee save in Win64 ABI, argument in AMD64 ABI. +#endif + __ push(rbx); + // TODO(X64): On Win64, if we ever use XMM6-XMM15, the low low 64 bits are + // callee save as well. + + // Save copies of the top frame descriptor on the stack. + ExternalReference c_entry_fp(Top::k_c_entry_fp_address); + __ load_rax(c_entry_fp); + __ push(rax); + + // Set up the roots and smi constant registers. + // Needs to be done before any further smi loads. + ExternalReference roots_address = ExternalReference::roots_address(); + __ movq(kRootRegister, roots_address); + __ InitializeSmiConstantRegister(); + +#ifdef ENABLE_LOGGING_AND_PROFILING + // If this is the outermost JS call, set js_entry_sp value. + ExternalReference js_entry_sp(Top::k_js_entry_sp_address); + __ load_rax(js_entry_sp); + __ testq(rax, rax); + __ j(not_zero, ¬_outermost_js); + __ movq(rax, rbp); + __ store_rax(js_entry_sp); + __ bind(¬_outermost_js); +#endif + + // Call a faked try-block that does the invoke. + __ call(&invoke); + + // Caught exception: Store result (exception) in the pending + // exception field in the JSEnv and return a failure sentinel. + ExternalReference pending_exception(Top::k_pending_exception_address); + __ store_rax(pending_exception); + __ movq(rax, Failure::Exception(), RelocInfo::NONE); + __ jmp(&exit); + + // Invoke: Link this frame into the handler chain. + __ bind(&invoke); + __ PushTryHandler(IN_JS_ENTRY, JS_ENTRY_HANDLER); + + // Clear any pending exceptions. + __ load_rax(ExternalReference::the_hole_value_location()); + __ store_rax(pending_exception); + + // Fake a receiver (NULL). + __ push(Immediate(0)); // receiver + + // Invoke the function by calling through JS entry trampoline + // builtin and pop the faked function when we return. We load the address + // from an external reference instead of inlining the call target address + // directly in the code, because the builtin stubs may not have been + // generated yet at the time this code is generated. + if (is_construct) { + ExternalReference construct_entry(Builtins::JSConstructEntryTrampoline); + __ load_rax(construct_entry); + } else { + ExternalReference entry(Builtins::JSEntryTrampoline); + __ load_rax(entry); + } + __ lea(kScratchRegister, FieldOperand(rax, Code::kHeaderSize)); + __ call(kScratchRegister); + + // Unlink this frame from the handler chain. + __ movq(kScratchRegister, ExternalReference(Top::k_handler_address)); + __ pop(Operand(kScratchRegister, 0)); + // Pop next_sp. + __ addq(rsp, Immediate(StackHandlerConstants::kSize - kPointerSize)); + +#ifdef ENABLE_LOGGING_AND_PROFILING + // If current EBP value is the same as js_entry_sp value, it means that + // the current function is the outermost. + __ movq(kScratchRegister, js_entry_sp); + __ cmpq(rbp, Operand(kScratchRegister, 0)); + __ j(not_equal, ¬_outermost_js_2); + __ movq(Operand(kScratchRegister, 0), Immediate(0)); + __ bind(¬_outermost_js_2); +#endif + + // Restore the top frame descriptor from the stack. + __ bind(&exit); + __ movq(kScratchRegister, ExternalReference(Top::k_c_entry_fp_address)); + __ pop(Operand(kScratchRegister, 0)); + + // Restore callee-saved registers (X64 conventions). + __ pop(rbx); +#ifdef _WIN64 + // Callee save on in Win64 ABI, arguments/volatile in AMD64 ABI. + __ pop(rsi); + __ pop(rdi); +#endif + __ pop(r15); + __ pop(r14); + __ pop(r13); + __ pop(r12); + __ addq(rsp, Immediate(2 * kPointerSize)); // remove markers + + // Restore frame pointer and return. + __ pop(rbp); + __ ret(0); +} + + +void InstanceofStub::Generate(MacroAssembler* masm) { + // Implements "value instanceof function" operator. + // Expected input state: + // rsp[0] : return address + // rsp[1] : function pointer + // rsp[2] : value + // Returns a bitwise zero to indicate that the value + // is and instance of the function and anything else to + // indicate that the value is not an instance. + + // Get the object - go slow case if it's a smi. + Label slow; + __ movq(rax, Operand(rsp, 2 * kPointerSize)); + __ JumpIfSmi(rax, &slow); + + // Check that the left hand is a JS object. Leave its map in rax. + __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rax); + __ j(below, &slow); + __ CmpInstanceType(rax, LAST_JS_OBJECT_TYPE); + __ j(above, &slow); + + // Get the prototype of the function. + __ movq(rdx, Operand(rsp, 1 * kPointerSize)); + // rdx is function, rax is map. + + // Look up the function and the map in the instanceof cache. + Label miss; + __ CompareRoot(rdx, Heap::kInstanceofCacheFunctionRootIndex); + __ j(not_equal, &miss); + __ CompareRoot(rax, Heap::kInstanceofCacheMapRootIndex); + __ j(not_equal, &miss); + __ LoadRoot(rax, Heap::kInstanceofCacheAnswerRootIndex); + __ ret(2 * kPointerSize); + + __ bind(&miss); + __ TryGetFunctionPrototype(rdx, rbx, &slow); + + // Check that the function prototype is a JS object. + __ JumpIfSmi(rbx, &slow); + __ CmpObjectType(rbx, FIRST_JS_OBJECT_TYPE, kScratchRegister); + __ j(below, &slow); + __ CmpInstanceType(kScratchRegister, LAST_JS_OBJECT_TYPE); + __ j(above, &slow); + + // Register mapping: + // rax is object map. + // rdx is function. + // rbx is function prototype. + __ StoreRoot(rdx, Heap::kInstanceofCacheFunctionRootIndex); + __ StoreRoot(rax, Heap::kInstanceofCacheMapRootIndex); + + __ movq(rcx, FieldOperand(rax, Map::kPrototypeOffset)); + + // Loop through the prototype chain looking for the function prototype. + Label loop, is_instance, is_not_instance; + __ LoadRoot(kScratchRegister, Heap::kNullValueRootIndex); + __ bind(&loop); + __ cmpq(rcx, rbx); + __ j(equal, &is_instance); + __ cmpq(rcx, kScratchRegister); + // The code at is_not_instance assumes that kScratchRegister contains a + // non-zero GCable value (the null object in this case). + __ j(equal, &is_not_instance); + __ movq(rcx, FieldOperand(rcx, HeapObject::kMapOffset)); + __ movq(rcx, FieldOperand(rcx, Map::kPrototypeOffset)); + __ jmp(&loop); + + __ bind(&is_instance); + __ xorl(rax, rax); + // Store bitwise zero in the cache. This is a Smi in GC terms. + STATIC_ASSERT(kSmiTag == 0); + __ StoreRoot(rax, Heap::kInstanceofCacheAnswerRootIndex); + __ ret(2 * kPointerSize); + + __ bind(&is_not_instance); + // We have to store a non-zero value in the cache. + __ StoreRoot(kScratchRegister, Heap::kInstanceofCacheAnswerRootIndex); + __ ret(2 * kPointerSize); + + // Slow-case: Go through the JavaScript implementation. + __ bind(&slow); + __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION); +} + + +int CompareStub::MinorKey() { + // Encode the three parameters in a unique 16 bit value. To avoid duplicate + // stubs the never NaN NaN condition is only taken into account if the + // condition is equals. + ASSERT(static_cast<unsigned>(cc_) < (1 << 12)); + ASSERT(lhs_.is(no_reg) && rhs_.is(no_reg)); + return ConditionField::encode(static_cast<unsigned>(cc_)) + | RegisterField::encode(false) // lhs_ and rhs_ are not used + | StrictField::encode(strict_) + | NeverNanNanField::encode(cc_ == equal ? never_nan_nan_ : false) + | IncludeNumberCompareField::encode(include_number_compare_); +} + + +// 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. +const char* CompareStub::GetName() { + ASSERT(lhs_.is(no_reg) && rhs_.is(no_reg)); + + if (name_ != NULL) return name_; + const int kMaxNameLength = 100; + name_ = Bootstrapper::AllocateAutoDeletedArray(kMaxNameLength); + if (name_ == NULL) return "OOM"; + + const char* cc_name; + switch (cc_) { + case less: cc_name = "LT"; break; + case greater: cc_name = "GT"; break; + case less_equal: cc_name = "LE"; break; + case greater_equal: cc_name = "GE"; break; + case equal: cc_name = "EQ"; break; + case not_equal: cc_name = "NE"; break; + default: cc_name = "UnknownCondition"; break; + } + + const char* strict_name = ""; + if (strict_ && (cc_ == equal || cc_ == not_equal)) { + strict_name = "_STRICT"; + } + + const char* never_nan_nan_name = ""; + if (never_nan_nan_ && (cc_ == equal || cc_ == not_equal)) { + never_nan_nan_name = "_NO_NAN"; + } + + const char* include_number_compare_name = ""; + if (!include_number_compare_) { + include_number_compare_name = "_NO_NUMBER"; + } + + OS::SNPrintF(Vector<char>(name_, kMaxNameLength), + "CompareStub_%s%s%s%s", + cc_name, + strict_name, + never_nan_nan_name, + include_number_compare_name); + return name_; +} + + +// ------------------------------------------------------------------------- +// StringCharCodeAtGenerator + +void StringCharCodeAtGenerator::GenerateFast(MacroAssembler* masm) { + Label flat_string; + Label ascii_string; + Label got_char_code; + + // If the receiver is a smi trigger the non-string case. + __ JumpIfSmi(object_, receiver_not_string_); + + // Fetch the instance type of the receiver into result register. + __ movq(result_, FieldOperand(object_, HeapObject::kMapOffset)); + __ movzxbl(result_, FieldOperand(result_, Map::kInstanceTypeOffset)); + // If the receiver is not a string trigger the non-string case. + __ testb(result_, Immediate(kIsNotStringMask)); + __ j(not_zero, receiver_not_string_); + + // If the index is non-smi trigger the non-smi case. + __ JumpIfNotSmi(index_, &index_not_smi_); + + // Put smi-tagged index into scratch register. + __ movq(scratch_, index_); + __ bind(&got_smi_index_); + + // Check for index out of range. + __ SmiCompare(scratch_, FieldOperand(object_, String::kLengthOffset)); + __ j(above_equal, index_out_of_range_); + + // We need special handling for non-flat strings. + STATIC_ASSERT(kSeqStringTag == 0); + __ testb(result_, Immediate(kStringRepresentationMask)); + __ j(zero, &flat_string); + + // Handle non-flat strings. + __ testb(result_, Immediate(kIsConsStringMask)); + __ j(zero, &call_runtime_); + + // ConsString. + // Check whether the right hand side is the empty string (i.e. if + // this is really a flat string in a cons string). If that is not + // the case we would rather go to the runtime system now to flatten + // the string. + __ CompareRoot(FieldOperand(object_, ConsString::kSecondOffset), + Heap::kEmptyStringRootIndex); + __ j(not_equal, &call_runtime_); + // Get the first of the two strings and load its instance type. + __ movq(object_, FieldOperand(object_, ConsString::kFirstOffset)); + __ movq(result_, FieldOperand(object_, HeapObject::kMapOffset)); + __ movzxbl(result_, FieldOperand(result_, Map::kInstanceTypeOffset)); + // If the first cons component is also non-flat, then go to runtime. + STATIC_ASSERT(kSeqStringTag == 0); + __ testb(result_, Immediate(kStringRepresentationMask)); + __ j(not_zero, &call_runtime_); + + // Check for 1-byte or 2-byte string. + __ bind(&flat_string); + STATIC_ASSERT(kAsciiStringTag != 0); + __ testb(result_, Immediate(kStringEncodingMask)); + __ j(not_zero, &ascii_string); + + // 2-byte string. + // Load the 2-byte character code into the result register. + __ SmiToInteger32(scratch_, scratch_); + __ movzxwl(result_, FieldOperand(object_, + scratch_, times_2, + SeqTwoByteString::kHeaderSize)); + __ jmp(&got_char_code); + + // ASCII string. + // Load the byte into the result register. + __ bind(&ascii_string); + __ SmiToInteger32(scratch_, scratch_); + __ movzxbl(result_, FieldOperand(object_, + scratch_, times_1, + SeqAsciiString::kHeaderSize)); + __ bind(&got_char_code); + __ Integer32ToSmi(result_, result_); + __ bind(&exit_); +} + + +void StringCharCodeAtGenerator::GenerateSlow( + MacroAssembler* masm, const RuntimeCallHelper& call_helper) { + __ Abort("Unexpected fallthrough to CharCodeAt slow case"); + + // Index is not a smi. + __ bind(&index_not_smi_); + // If index is a heap number, try converting it to an integer. + __ CheckMap(index_, Factory::heap_number_map(), index_not_number_, true); + call_helper.BeforeCall(masm); + __ push(object_); + __ push(index_); + __ push(index_); // Consumed by runtime conversion function. + if (index_flags_ == STRING_INDEX_IS_NUMBER) { + __ CallRuntime(Runtime::kNumberToIntegerMapMinusZero, 1); + } else { + ASSERT(index_flags_ == STRING_INDEX_IS_ARRAY_INDEX); + // NumberToSmi discards numbers that are not exact integers. + __ CallRuntime(Runtime::kNumberToSmi, 1); + } + if (!scratch_.is(rax)) { + // Save the conversion result before the pop instructions below + // have a chance to overwrite it. + __ movq(scratch_, rax); + } + __ pop(index_); + __ pop(object_); + // Reload the instance type. + __ movq(result_, FieldOperand(object_, HeapObject::kMapOffset)); + __ movzxbl(result_, FieldOperand(result_, Map::kInstanceTypeOffset)); + call_helper.AfterCall(masm); + // If index is still not a smi, it must be out of range. + __ JumpIfNotSmi(scratch_, index_out_of_range_); + // Otherwise, return to the fast path. + __ jmp(&got_smi_index_); + + // Call runtime. We get here when the receiver is a string and the + // index is a number, but the code of getting the actual character + // is too complex (e.g., when the string needs to be flattened). + __ bind(&call_runtime_); + call_helper.BeforeCall(masm); + __ push(object_); + __ push(index_); + __ CallRuntime(Runtime::kStringCharCodeAt, 2); + if (!result_.is(rax)) { + __ movq(result_, rax); + } + call_helper.AfterCall(masm); + __ jmp(&exit_); + + __ Abort("Unexpected fallthrough from CharCodeAt slow case"); +} + + +// ------------------------------------------------------------------------- +// StringCharFromCodeGenerator + +void StringCharFromCodeGenerator::GenerateFast(MacroAssembler* masm) { + // Fast case of Heap::LookupSingleCharacterStringFromCode. + __ JumpIfNotSmi(code_, &slow_case_); + __ SmiCompare(code_, Smi::FromInt(String::kMaxAsciiCharCode)); + __ j(above, &slow_case_); + + __ LoadRoot(result_, Heap::kSingleCharacterStringCacheRootIndex); + SmiIndex index = masm->SmiToIndex(kScratchRegister, code_, kPointerSizeLog2); + __ movq(result_, FieldOperand(result_, index.reg, index.scale, + FixedArray::kHeaderSize)); + __ CompareRoot(result_, Heap::kUndefinedValueRootIndex); + __ j(equal, &slow_case_); + __ bind(&exit_); +} + + +void StringCharFromCodeGenerator::GenerateSlow( + MacroAssembler* masm, const RuntimeCallHelper& call_helper) { + __ Abort("Unexpected fallthrough to CharFromCode slow case"); + + __ bind(&slow_case_); + call_helper.BeforeCall(masm); + __ push(code_); + __ CallRuntime(Runtime::kCharFromCode, 1); + if (!result_.is(rax)) { + __ movq(result_, rax); + } + call_helper.AfterCall(masm); + __ jmp(&exit_); + + __ Abort("Unexpected fallthrough from CharFromCode slow case"); +} + + +// ------------------------------------------------------------------------- +// StringCharAtGenerator + +void StringCharAtGenerator::GenerateFast(MacroAssembler* masm) { + char_code_at_generator_.GenerateFast(masm); + char_from_code_generator_.GenerateFast(masm); +} + + +void StringCharAtGenerator::GenerateSlow( + MacroAssembler* masm, const RuntimeCallHelper& call_helper) { + char_code_at_generator_.GenerateSlow(masm, call_helper); + char_from_code_generator_.GenerateSlow(masm, call_helper); +} + + +void StringAddStub::Generate(MacroAssembler* masm) { + Label string_add_runtime; + + // Load the two arguments. + __ movq(rax, Operand(rsp, 2 * kPointerSize)); // First argument. + __ movq(rdx, Operand(rsp, 1 * kPointerSize)); // Second argument. + + // Make sure that both arguments are strings if not known in advance. + if (string_check_) { + Condition is_smi; + is_smi = masm->CheckSmi(rax); + __ j(is_smi, &string_add_runtime); + __ CmpObjectType(rax, FIRST_NONSTRING_TYPE, r8); + __ j(above_equal, &string_add_runtime); + + // First argument is a a string, test second. + is_smi = masm->CheckSmi(rdx); + __ j(is_smi, &string_add_runtime); + __ CmpObjectType(rdx, FIRST_NONSTRING_TYPE, r9); + __ j(above_equal, &string_add_runtime); + } + + // Both arguments are strings. + // rax: first string + // rdx: second string + // Check if either of the strings are empty. In that case return the other. + Label second_not_zero_length, both_not_zero_length; + __ movq(rcx, FieldOperand(rdx, String::kLengthOffset)); + __ SmiTest(rcx); + __ j(not_zero, &second_not_zero_length); + // Second string is empty, result is first string which is already in rax. + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + __ bind(&second_not_zero_length); + __ movq(rbx, FieldOperand(rax, String::kLengthOffset)); + __ SmiTest(rbx); + __ j(not_zero, &both_not_zero_length); + // First string is empty, result is second string which is in rdx. + __ movq(rax, rdx); + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + + // Both strings are non-empty. + // rax: first string + // rbx: length of first string + // rcx: length of second string + // rdx: second string + // r8: map of first string if string check was performed above + // r9: map of second string if string check was performed above + Label string_add_flat_result, longer_than_two; + __ bind(&both_not_zero_length); + + // If arguments where known to be strings, maps are not loaded to r8 and r9 + // by the code above. + if (!string_check_) { + __ movq(r8, FieldOperand(rax, HeapObject::kMapOffset)); + __ movq(r9, FieldOperand(rdx, HeapObject::kMapOffset)); + } + // Get the instance types of the two strings as they will be needed soon. + __ movzxbl(r8, FieldOperand(r8, Map::kInstanceTypeOffset)); + __ movzxbl(r9, FieldOperand(r9, Map::kInstanceTypeOffset)); + + // Look at the length of the result of adding the two strings. + STATIC_ASSERT(String::kMaxLength <= Smi::kMaxValue / 2); + __ SmiAdd(rbx, rbx, rcx, NULL); + // Use the runtime system when adding two one character strings, as it + // contains optimizations for this specific case using the symbol table. + __ SmiCompare(rbx, Smi::FromInt(2)); + __ j(not_equal, &longer_than_two); + + // Check that both strings are non-external ascii strings. + __ JumpIfBothInstanceTypesAreNotSequentialAscii(r8, r9, rbx, rcx, + &string_add_runtime); + + // Get the two characters forming the sub string. + __ movzxbq(rbx, FieldOperand(rax, SeqAsciiString::kHeaderSize)); + __ movzxbq(rcx, FieldOperand(rdx, SeqAsciiString::kHeaderSize)); + + // Try to lookup two character string in symbol table. If it is not found + // just allocate a new one. + Label make_two_character_string, make_flat_ascii_string; + StringHelper::GenerateTwoCharacterSymbolTableProbe( + masm, rbx, rcx, r14, r11, rdi, r12, &make_two_character_string); + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + + __ bind(&make_two_character_string); + __ Set(rbx, 2); + __ jmp(&make_flat_ascii_string); + + __ bind(&longer_than_two); + // Check if resulting string will be flat. + __ SmiCompare(rbx, Smi::FromInt(String::kMinNonFlatLength)); + __ j(below, &string_add_flat_result); + // Handle exceptionally long strings in the runtime system. + STATIC_ASSERT((String::kMaxLength & 0x80000000) == 0); + __ SmiCompare(rbx, Smi::FromInt(String::kMaxLength)); + __ j(above, &string_add_runtime); + + // If result is not supposed to be flat, allocate a cons string object. If + // both strings are ascii the result is an ascii cons string. + // rax: first string + // rbx: length of resulting flat string + // rdx: second string + // r8: instance type of first string + // r9: instance type of second string + Label non_ascii, allocated, ascii_data; + __ movl(rcx, r8); + __ and_(rcx, r9); + STATIC_ASSERT(kStringEncodingMask == kAsciiStringTag); + __ testl(rcx, Immediate(kAsciiStringTag)); + __ j(zero, &non_ascii); + __ bind(&ascii_data); + // Allocate an acsii cons string. + __ AllocateAsciiConsString(rcx, rdi, no_reg, &string_add_runtime); + __ bind(&allocated); + // Fill the fields of the cons string. + __ movq(FieldOperand(rcx, ConsString::kLengthOffset), rbx); + __ movq(FieldOperand(rcx, ConsString::kHashFieldOffset), + Immediate(String::kEmptyHashField)); + __ movq(FieldOperand(rcx, ConsString::kFirstOffset), rax); + __ movq(FieldOperand(rcx, ConsString::kSecondOffset), rdx); + __ movq(rax, rcx); + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + __ bind(&non_ascii); + // At least one of the strings is two-byte. Check whether it happens + // to contain only ascii characters. + // rcx: first instance type AND second instance type. + // r8: first instance type. + // r9: second instance type. + __ testb(rcx, Immediate(kAsciiDataHintMask)); + __ j(not_zero, &ascii_data); + __ xor_(r8, r9); + STATIC_ASSERT(kAsciiStringTag != 0 && kAsciiDataHintTag != 0); + __ andb(r8, Immediate(kAsciiStringTag | kAsciiDataHintTag)); + __ cmpb(r8, Immediate(kAsciiStringTag | kAsciiDataHintTag)); + __ j(equal, &ascii_data); + // Allocate a two byte cons string. + __ AllocateConsString(rcx, rdi, no_reg, &string_add_runtime); + __ jmp(&allocated); + + // Handle creating a flat result. First check that both strings are not + // external strings. + // rax: first string + // rbx: length of resulting flat string as smi + // rdx: second string + // r8: instance type of first string + // r9: instance type of first string + __ bind(&string_add_flat_result); + __ SmiToInteger32(rbx, rbx); + __ movl(rcx, r8); + __ and_(rcx, Immediate(kStringRepresentationMask)); + __ cmpl(rcx, Immediate(kExternalStringTag)); + __ j(equal, &string_add_runtime); + __ movl(rcx, r9); + __ and_(rcx, Immediate(kStringRepresentationMask)); + __ cmpl(rcx, Immediate(kExternalStringTag)); + __ j(equal, &string_add_runtime); + // Now check if both strings are ascii strings. + // rax: first string + // rbx: length of resulting flat string + // rdx: second string + // r8: instance type of first string + // r9: instance type of second string + Label non_ascii_string_add_flat_result; + STATIC_ASSERT(kStringEncodingMask == kAsciiStringTag); + __ testl(r8, Immediate(kAsciiStringTag)); + __ j(zero, &non_ascii_string_add_flat_result); + __ testl(r9, Immediate(kAsciiStringTag)); + __ j(zero, &string_add_runtime); + + __ bind(&make_flat_ascii_string); + // Both strings are ascii strings. As they are short they are both flat. + __ AllocateAsciiString(rcx, rbx, rdi, r14, r11, &string_add_runtime); + // rcx: result string + __ movq(rbx, rcx); + // Locate first character of result. + __ addq(rcx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag)); + // Locate first character of first argument + __ SmiToInteger32(rdi, FieldOperand(rax, String::kLengthOffset)); + __ addq(rax, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag)); + // rax: first char of first argument + // rbx: result string + // rcx: first character of result + // rdx: second string + // rdi: length of first argument + StringHelper::GenerateCopyCharacters(masm, rcx, rax, rdi, true); + // Locate first character of second argument. + __ SmiToInteger32(rdi, FieldOperand(rdx, String::kLengthOffset)); + __ addq(rdx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag)); + // rbx: result string + // rcx: next character of result + // rdx: first char of second argument + // rdi: length of second argument + StringHelper::GenerateCopyCharacters(masm, rcx, rdx, rdi, true); + __ movq(rax, rbx); + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + + // Handle creating a flat two byte result. + // rax: first string - known to be two byte + // rbx: length of resulting flat string + // rdx: second string + // r8: instance type of first string + // r9: instance type of first string + __ bind(&non_ascii_string_add_flat_result); + __ and_(r9, Immediate(kAsciiStringTag)); + __ j(not_zero, &string_add_runtime); + // Both strings are two byte strings. As they are short they are both + // flat. + __ AllocateTwoByteString(rcx, rbx, rdi, r14, r11, &string_add_runtime); + // rcx: result string + __ movq(rbx, rcx); + // Locate first character of result. + __ addq(rcx, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag)); + // Locate first character of first argument. + __ SmiToInteger32(rdi, FieldOperand(rax, String::kLengthOffset)); + __ addq(rax, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag)); + // rax: first char of first argument + // rbx: result string + // rcx: first character of result + // rdx: second argument + // rdi: length of first argument + StringHelper::GenerateCopyCharacters(masm, rcx, rax, rdi, false); + // Locate first character of second argument. + __ SmiToInteger32(rdi, FieldOperand(rdx, String::kLengthOffset)); + __ addq(rdx, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag)); + // rbx: result string + // rcx: next character of result + // rdx: first char of second argument + // rdi: length of second argument + StringHelper::GenerateCopyCharacters(masm, rcx, rdx, rdi, false); + __ movq(rax, rbx); + __ IncrementCounter(&Counters::string_add_native, 1); + __ ret(2 * kPointerSize); + + // Just jump to runtime to add the two strings. + __ bind(&string_add_runtime); + __ TailCallRuntime(Runtime::kStringAdd, 2, 1); +} + + +void StringHelper::GenerateCopyCharacters(MacroAssembler* masm, + Register dest, + Register src, + Register count, + bool ascii) { + Label loop; + __ bind(&loop); + // This loop just copies one character at a time, as it is only used for very + // short strings. + if (ascii) { + __ movb(kScratchRegister, Operand(src, 0)); + __ movb(Operand(dest, 0), kScratchRegister); + __ incq(src); + __ incq(dest); + } else { + __ movzxwl(kScratchRegister, Operand(src, 0)); + __ movw(Operand(dest, 0), kScratchRegister); + __ addq(src, Immediate(2)); + __ addq(dest, Immediate(2)); + } + __ decl(count); + __ j(not_zero, &loop); +} + + +void StringHelper::GenerateCopyCharactersREP(MacroAssembler* masm, + Register dest, + Register src, + Register count, + bool ascii) { + // Copy characters using rep movs of doublewords. Align destination on 4 byte + // boundary before starting rep movs. Copy remaining characters after running + // rep movs. + // Count is positive int32, dest and src are character pointers. + ASSERT(dest.is(rdi)); // rep movs destination + ASSERT(src.is(rsi)); // rep movs source + ASSERT(count.is(rcx)); // rep movs count + + // Nothing to do for zero characters. + Label done; + __ testl(count, count); + __ j(zero, &done); + + // Make count the number of bytes to copy. + if (!ascii) { + STATIC_ASSERT(2 == sizeof(uc16)); + __ addl(count, count); + } + + // Don't enter the rep movs if there are less than 4 bytes to copy. + Label last_bytes; + __ testl(count, Immediate(~7)); + __ j(zero, &last_bytes); + + // Copy from edi to esi using rep movs instruction. + __ movl(kScratchRegister, count); + __ shr(count, Immediate(3)); // Number of doublewords to copy. + __ repmovsq(); + + // Find number of bytes left. + __ movl(count, kScratchRegister); + __ and_(count, Immediate(7)); + + // Check if there are more bytes to copy. + __ bind(&last_bytes); + __ testl(count, count); + __ j(zero, &done); + + // Copy remaining characters. + Label loop; + __ bind(&loop); + __ movb(kScratchRegister, Operand(src, 0)); + __ movb(Operand(dest, 0), kScratchRegister); + __ incq(src); + __ incq(dest); + __ decl(count); + __ j(not_zero, &loop); + + __ bind(&done); +} + +void StringHelper::GenerateTwoCharacterSymbolTableProbe(MacroAssembler* masm, + Register c1, + Register c2, + Register scratch1, + Register scratch2, + Register scratch3, + Register scratch4, + Label* not_found) { + // Register scratch3 is the general scratch register in this function. + Register scratch = scratch3; + + // Make sure that both characters are not digits as such strings has a + // different hash algorithm. Don't try to look for these in the symbol table. + Label not_array_index; + __ leal(scratch, Operand(c1, -'0')); + __ cmpl(scratch, Immediate(static_cast<int>('9' - '0'))); + __ j(above, ¬_array_index); + __ leal(scratch, Operand(c2, -'0')); + __ cmpl(scratch, Immediate(static_cast<int>('9' - '0'))); + __ j(below_equal, not_found); + + __ bind(¬_array_index); + // Calculate the two character string hash. + Register hash = scratch1; + GenerateHashInit(masm, hash, c1, scratch); + GenerateHashAddCharacter(masm, hash, c2, scratch); + GenerateHashGetHash(masm, hash, scratch); + + // Collect the two characters in a register. + Register chars = c1; + __ shl(c2, Immediate(kBitsPerByte)); + __ orl(chars, c2); + + // chars: two character string, char 1 in byte 0 and char 2 in byte 1. + // hash: hash of two character string. + + // Load the symbol table. + Register symbol_table = c2; + __ LoadRoot(symbol_table, Heap::kSymbolTableRootIndex); + + // Calculate capacity mask from the symbol table capacity. + Register mask = scratch2; + __ SmiToInteger32(mask, + FieldOperand(symbol_table, SymbolTable::kCapacityOffset)); + __ decl(mask); + + Register undefined = scratch4; + __ LoadRoot(undefined, Heap::kUndefinedValueRootIndex); + + // Registers + // chars: two character string, char 1 in byte 0 and char 2 in byte 1. + // hash: hash of two character string (32-bit int) + // symbol_table: symbol table + // mask: capacity mask (32-bit int) + // undefined: undefined value + // scratch: - + + // Perform a number of probes in the symbol table. + static const int kProbes = 4; + Label found_in_symbol_table; + Label next_probe[kProbes]; + for (int i = 0; i < kProbes; i++) { + // Calculate entry in symbol table. + __ movl(scratch, hash); + if (i > 0) { + __ addl(scratch, Immediate(SymbolTable::GetProbeOffset(i))); + } + __ andl(scratch, mask); + + // Load the entry from the symble table. + Register candidate = scratch; // Scratch register contains candidate. + STATIC_ASSERT(SymbolTable::kEntrySize == 1); + __ movq(candidate, + FieldOperand(symbol_table, + scratch, + times_pointer_size, + SymbolTable::kElementsStartOffset)); + + // If entry is undefined no string with this hash can be found. + __ cmpq(candidate, undefined); + __ j(equal, not_found); + + // If length is not 2 the string is not a candidate. + __ SmiCompare(FieldOperand(candidate, String::kLengthOffset), + Smi::FromInt(2)); + __ j(not_equal, &next_probe[i]); + + // We use kScratchRegister as a temporary register in assumption that + // JumpIfInstanceTypeIsNotSequentialAscii does not use it implicitly + Register temp = kScratchRegister; + + // Check that the candidate is a non-external ascii string. + __ movq(temp, FieldOperand(candidate, HeapObject::kMapOffset)); + __ movzxbl(temp, FieldOperand(temp, Map::kInstanceTypeOffset)); + __ JumpIfInstanceTypeIsNotSequentialAscii( + temp, temp, &next_probe[i]); + + // Check if the two characters match. + __ movl(temp, FieldOperand(candidate, SeqAsciiString::kHeaderSize)); + __ andl(temp, Immediate(0x0000ffff)); + __ cmpl(chars, temp); + __ j(equal, &found_in_symbol_table); + __ bind(&next_probe[i]); + } + + // No matching 2 character string found by probing. + __ jmp(not_found); + + // Scratch register contains result when we fall through to here. + Register result = scratch; + __ bind(&found_in_symbol_table); + if (!result.is(rax)) { + __ movq(rax, result); + } +} + + +void StringHelper::GenerateHashInit(MacroAssembler* masm, + Register hash, + Register character, + Register scratch) { + // hash = character + (character << 10); + __ movl(hash, character); + __ shll(hash, Immediate(10)); + __ addl(hash, character); + // hash ^= hash >> 6; + __ movl(scratch, hash); + __ sarl(scratch, Immediate(6)); + __ xorl(hash, scratch); +} + + +void StringHelper::GenerateHashAddCharacter(MacroAssembler* masm, + Register hash, + Register character, + Register scratch) { + // hash += character; + __ addl(hash, character); + // hash += hash << 10; + __ movl(scratch, hash); + __ shll(scratch, Immediate(10)); + __ addl(hash, scratch); + // hash ^= hash >> 6; + __ movl(scratch, hash); + __ sarl(scratch, Immediate(6)); + __ xorl(hash, scratch); +} + + +void StringHelper::GenerateHashGetHash(MacroAssembler* masm, + Register hash, + Register scratch) { + // hash += hash << 3; + __ leal(hash, Operand(hash, hash, times_8, 0)); + // hash ^= hash >> 11; + __ movl(scratch, hash); + __ sarl(scratch, Immediate(11)); + __ xorl(hash, scratch); + // hash += hash << 15; + __ movl(scratch, hash); + __ shll(scratch, Immediate(15)); + __ addl(hash, scratch); + + // if (hash == 0) hash = 27; + Label hash_not_zero; + __ j(not_zero, &hash_not_zero); + __ movl(hash, Immediate(27)); + __ bind(&hash_not_zero); +} + +void SubStringStub::Generate(MacroAssembler* masm) { + Label runtime; + + // Stack frame on entry. + // rsp[0]: return address + // rsp[8]: to + // rsp[16]: from + // rsp[24]: string + + const int kToOffset = 1 * kPointerSize; + const int kFromOffset = kToOffset + kPointerSize; + const int kStringOffset = kFromOffset + kPointerSize; + const int kArgumentsSize = (kStringOffset + kPointerSize) - kToOffset; + + // Make sure first argument is a string. + __ movq(rax, Operand(rsp, kStringOffset)); + STATIC_ASSERT(kSmiTag == 0); + __ testl(rax, Immediate(kSmiTagMask)); + __ j(zero, &runtime); + Condition is_string = masm->IsObjectStringType(rax, rbx, rbx); + __ j(NegateCondition(is_string), &runtime); + + // rax: string + // rbx: instance type + // Calculate length of sub string using the smi values. + Label result_longer_than_two; + __ movq(rcx, Operand(rsp, kToOffset)); + __ movq(rdx, Operand(rsp, kFromOffset)); + __ JumpIfNotBothPositiveSmi(rcx, rdx, &runtime); + + __ SmiSub(rcx, rcx, rdx, NULL); // Overflow doesn't happen. + __ cmpq(FieldOperand(rax, String::kLengthOffset), rcx); + Label return_rax; + __ j(equal, &return_rax); + // Special handling of sub-strings of length 1 and 2. One character strings + // are handled in the runtime system (looked up in the single character + // cache). Two character strings are looked for in the symbol cache. + __ SmiToInteger32(rcx, rcx); + __ cmpl(rcx, Immediate(2)); + __ j(greater, &result_longer_than_two); + __ j(less, &runtime); + + // Sub string of length 2 requested. + // rax: string + // rbx: instance type + // rcx: sub string length (value is 2) + // rdx: from index (smi) + __ JumpIfInstanceTypeIsNotSequentialAscii(rbx, rbx, &runtime); + + // Get the two characters forming the sub string. + __ SmiToInteger32(rdx, rdx); // From index is no longer smi. + __ movzxbq(rbx, FieldOperand(rax, rdx, times_1, SeqAsciiString::kHeaderSize)); + __ movzxbq(rcx, + FieldOperand(rax, rdx, times_1, SeqAsciiString::kHeaderSize + 1)); + + // Try to lookup two character string in symbol table. + Label make_two_character_string; + StringHelper::GenerateTwoCharacterSymbolTableProbe( + masm, rbx, rcx, rax, rdx, rdi, r14, &make_two_character_string); + __ ret(3 * kPointerSize); + + __ bind(&make_two_character_string); + // Setup registers for allocating the two character string. + __ movq(rax, Operand(rsp, kStringOffset)); + __ movq(rbx, FieldOperand(rax, HeapObject::kMapOffset)); + __ movzxbl(rbx, FieldOperand(rbx, Map::kInstanceTypeOffset)); + __ Set(rcx, 2); + + __ bind(&result_longer_than_two); + + // rax: string + // rbx: instance type + // rcx: result string length + // Check for flat ascii string + Label non_ascii_flat; + __ JumpIfInstanceTypeIsNotSequentialAscii(rbx, rbx, &non_ascii_flat); + + // Allocate the result. + __ AllocateAsciiString(rax, rcx, rbx, rdx, rdi, &runtime); + + // rax: result string + // rcx: result string length + __ movq(rdx, rsi); // esi used by following code. + // Locate first character of result. + __ lea(rdi, FieldOperand(rax, SeqAsciiString::kHeaderSize)); + // Load string argument and locate character of sub string start. + __ movq(rsi, Operand(rsp, kStringOffset)); + __ movq(rbx, Operand(rsp, kFromOffset)); + { + SmiIndex smi_as_index = masm->SmiToIndex(rbx, rbx, times_1); + __ lea(rsi, Operand(rsi, smi_as_index.reg, smi_as_index.scale, + SeqAsciiString::kHeaderSize - kHeapObjectTag)); + } + + // rax: result string + // rcx: result length + // rdx: original value of rsi + // rdi: first character of result + // rsi: character of sub string start + StringHelper::GenerateCopyCharactersREP(masm, rdi, rsi, rcx, true); + __ movq(rsi, rdx); // Restore rsi. + __ IncrementCounter(&Counters::sub_string_native, 1); + __ ret(kArgumentsSize); + + __ bind(&non_ascii_flat); + // rax: string + // rbx: instance type & kStringRepresentationMask | kStringEncodingMask + // rcx: result string length + // Check for sequential two byte string + __ cmpb(rbx, Immediate(kSeqStringTag | kTwoByteStringTag)); + __ j(not_equal, &runtime); + + // Allocate the result. + __ AllocateTwoByteString(rax, rcx, rbx, rdx, rdi, &runtime); + + // rax: result string + // rcx: result string length + __ movq(rdx, rsi); // esi used by following code. + // Locate first character of result. + __ lea(rdi, FieldOperand(rax, SeqTwoByteString::kHeaderSize)); + // Load string argument and locate character of sub string start. + __ movq(rsi, Operand(rsp, kStringOffset)); + __ movq(rbx, Operand(rsp, kFromOffset)); + { + SmiIndex smi_as_index = masm->SmiToIndex(rbx, rbx, times_2); + __ lea(rsi, Operand(rsi, smi_as_index.reg, smi_as_index.scale, + SeqAsciiString::kHeaderSize - kHeapObjectTag)); + } + + // rax: result string + // rcx: result length + // rdx: original value of rsi + // rdi: first character of result + // rsi: character of sub string start + StringHelper::GenerateCopyCharactersREP(masm, rdi, rsi, rcx, false); + __ movq(rsi, rdx); // Restore esi. + + __ bind(&return_rax); + __ IncrementCounter(&Counters::sub_string_native, 1); + __ ret(kArgumentsSize); + + // Just jump to runtime to create the sub string. + __ bind(&runtime); + __ TailCallRuntime(Runtime::kSubString, 3, 1); +} + + +void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm, + Register left, + Register right, + Register scratch1, + Register scratch2, + Register scratch3, + Register scratch4) { + // Ensure that you can always subtract a string length from a non-negative + // number (e.g. another length). + STATIC_ASSERT(String::kMaxLength < 0x7fffffff); + + // Find minimum length and length difference. + __ movq(scratch1, FieldOperand(left, String::kLengthOffset)); + __ movq(scratch4, scratch1); + __ SmiSub(scratch4, + scratch4, + FieldOperand(right, String::kLengthOffset), + NULL); + // Register scratch4 now holds left.length - right.length. + const Register length_difference = scratch4; + Label left_shorter; + __ j(less, &left_shorter); + // The right string isn't longer that the left one. + // Get the right string's length by subtracting the (non-negative) difference + // from the left string's length. + __ SmiSub(scratch1, scratch1, length_difference, NULL); + __ bind(&left_shorter); + // Register scratch1 now holds Min(left.length, right.length). + const Register min_length = scratch1; + + Label compare_lengths; + // If min-length is zero, go directly to comparing lengths. + __ SmiTest(min_length); + __ j(zero, &compare_lengths); + + __ SmiToInteger32(min_length, min_length); + + // Registers scratch2 and scratch3 are free. + Label result_not_equal; + Label loop; + { + // Check characters 0 .. min_length - 1 in a loop. + // Use scratch3 as loop index, min_length as limit and scratch2 + // for computation. + const Register index = scratch3; + __ movl(index, Immediate(0)); // Index into strings. + __ bind(&loop); + // Compare characters. + // TODO(lrn): Could we load more than one character at a time? + __ movb(scratch2, FieldOperand(left, + index, + times_1, + SeqAsciiString::kHeaderSize)); + // Increment index and use -1 modifier on next load to give + // the previous load extra time to complete. + __ addl(index, Immediate(1)); + __ cmpb(scratch2, FieldOperand(right, + index, + times_1, + SeqAsciiString::kHeaderSize - 1)); + __ j(not_equal, &result_not_equal); + __ cmpl(index, min_length); + __ j(not_equal, &loop); + } + // Completed loop without finding different characters. + // Compare lengths (precomputed). + __ bind(&compare_lengths); + __ SmiTest(length_difference); + __ j(not_zero, &result_not_equal); + + // Result is EQUAL. + __ Move(rax, Smi::FromInt(EQUAL)); + __ ret(0); + + Label result_greater; + __ bind(&result_not_equal); + // Unequal comparison of left to right, either character or length. + __ j(greater, &result_greater); + + // Result is LESS. + __ Move(rax, Smi::FromInt(LESS)); + __ ret(0); + + // Result is GREATER. + __ bind(&result_greater); + __ Move(rax, Smi::FromInt(GREATER)); + __ ret(0); +} + + +void StringCompareStub::Generate(MacroAssembler* masm) { + Label runtime; + + // Stack frame on entry. + // rsp[0]: return address + // rsp[8]: right string + // rsp[16]: left string + + __ movq(rdx, Operand(rsp, 2 * kPointerSize)); // left + __ movq(rax, Operand(rsp, 1 * kPointerSize)); // right + + // Check for identity. + Label not_same; + __ cmpq(rdx, rax); + __ j(not_equal, ¬_same); + __ Move(rax, Smi::FromInt(EQUAL)); + __ IncrementCounter(&Counters::string_compare_native, 1); + __ ret(2 * kPointerSize); + + __ bind(¬_same); + + // Check that both are sequential ASCII strings. + __ JumpIfNotBothSequentialAsciiStrings(rdx, rax, rcx, rbx, &runtime); + + // Inline comparison of ascii strings. + __ IncrementCounter(&Counters::string_compare_native, 1); + // Drop arguments from the stack + __ pop(rcx); + __ addq(rsp, Immediate(2 * kPointerSize)); + __ push(rcx); + GenerateCompareFlatAsciiStrings(masm, rdx, rax, rcx, rbx, rdi, r8); + + // Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater) + // tagged as a small integer. + __ bind(&runtime); + __ TailCallRuntime(Runtime::kStringCompare, 2, 1); +} + +#undef __ + +} } // namespace v8::internal + +#endif // V8_TARGET_ARCH_X64 |