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// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/globals.h"
#if defined(TARGET_ARCH_ARM)
#include "vm/assembler.h"
#include "vm/code_generator.h"
#include "vm/cpu.h"
#include "vm/compiler.h"
#include "vm/dart_entry.h"
#include "vm/flow_graph_compiler.h"
#include "vm/heap.h"
#include "vm/instructions.h"
#include "vm/object_store.h"
#include "vm/stack_frame.h"
#include "vm/stub_code.h"
#include "vm/tags.h"
#define __ assembler->
namespace dart {
DEFINE_FLAG(bool, inline_alloc, true, "Inline allocation of objects.");
DEFINE_FLAG(bool, use_slow_path, false,
"Set to true for debugging & verifying the slow paths.");
DECLARE_FLAG(bool, trace_optimized_ic_calls);
DECLARE_FLAG(int, optimization_counter_threshold);
DECLARE_FLAG(bool, support_debugger);
DECLARE_FLAG(bool, lazy_dispatchers);
// Input parameters:
// LR : return address.
// SP : address of last argument in argument array.
// SP + 4*R4 - 4 : address of first argument in argument array.
// SP + 4*R4 : address of return value.
// R5 : address of the runtime function to call.
// R4 : number of arguments to the call.
void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
const intptr_t thread_offset = NativeArguments::thread_offset();
const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
const intptr_t argv_offset = NativeArguments::argv_offset();
const intptr_t retval_offset = NativeArguments::retval_offset();
__ EnterStubFrame();
// Save exit frame information to enable stack walking as we are about
// to transition to Dart VM C++ code.
__ StoreToOffset(kWord, FP, THR, Thread::top_exit_frame_info_offset());
#if defined(DEBUG)
{ Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(kWord, R6, THR, Thread::vm_tag_offset());
__ CompareImmediate(R6, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing VM code.
__ StoreToOffset(kWord, R5, THR, Thread::vm_tag_offset());
// Reserve space for arguments and align frame before entering C++ world.
// NativeArguments are passed in registers.
ASSERT(sizeof(NativeArguments) == 4 * kWordSize);
__ ReserveAlignedFrameSpace(0);
// Pass NativeArguments structure by value and call runtime.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * kWordSize);
// Set thread in NativeArgs.
__ mov(R0, Operand(THR));
// There are no runtime calls to closures, so we do not need to set the tag
// bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
ASSERT(argc_tag_offset == 1 * kWordSize);
__ mov(R1, Operand(R4)); // Set argc in NativeArguments.
ASSERT(argv_offset == 2 * kWordSize);
__ add(R2, FP, Operand(R4, LSL, 2)); // Compute argv.
// Set argv in NativeArguments.
__ AddImmediate(R2, kParamEndSlotFromFp * kWordSize);
ASSERT(retval_offset == 3 * kWordSize);
__ add(R3, R2, Operand(kWordSize)); // Retval is next to 1st argument.
// Call runtime or redirection via simulator.
__ blx(R5);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(kWord, R2, THR, Thread::vm_tag_offset());
// Reset exit frame information in Isolate structure.
__ LoadImmediate(R2, 0);
__ StoreToOffset(kWord, R2, THR, Thread::top_exit_frame_info_offset());
__ LeaveStubFrame();
__ Ret();
}
// Print the stop message.
DEFINE_LEAF_RUNTIME_ENTRY(void, PrintStopMessage, 1, const char* message) {
OS::Print("Stop message: %s\n", message);
}
END_LEAF_RUNTIME_ENTRY
// Input parameters:
// R0 : stop message (const char*).
// Must preserve all registers.
void StubCode::GeneratePrintStopMessageStub(Assembler* assembler) {
__ EnterCallRuntimeFrame(0);
// Call the runtime leaf function. R0 already contains the parameter.
__ CallRuntime(kPrintStopMessageRuntimeEntry, 1);
__ LeaveCallRuntimeFrame();
__ Ret();
}
// Input parameters:
// LR : return address.
// SP : address of return value.
// R5 : address of the native function to call.
// R2 : address of first argument in argument array.
// R1 : argc_tag including number of arguments and function kind.
void StubCode::GenerateCallNativeCFunctionStub(Assembler* assembler) {
const intptr_t thread_offset = NativeArguments::thread_offset();
const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
const intptr_t argv_offset = NativeArguments::argv_offset();
const intptr_t retval_offset = NativeArguments::retval_offset();
__ EnterStubFrame();
// Save exit frame information to enable stack walking as we are about
// to transition to native code.
__ StoreToOffset(kWord, FP, THR, Thread::top_exit_frame_info_offset());
#if defined(DEBUG)
{ Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(kWord, R6, THR, Thread::vm_tag_offset());
__ CompareImmediate(R6, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing native code.
__ StoreToOffset(kWord, R5, THR, Thread::vm_tag_offset());
// Reserve space for the native arguments structure passed on the stack (the
// outgoing pointer parameter to the native arguments structure is passed in
// R0) and align frame before entering the C++ world.
__ ReserveAlignedFrameSpace(sizeof(NativeArguments));
// Initialize NativeArguments structure and call native function.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * kWordSize);
// Set thread in NativeArgs.
__ mov(R0, Operand(THR));
// There are no native calls to closures, so we do not need to set the tag
// bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
ASSERT(argc_tag_offset == 1 * kWordSize);
// Set argc in NativeArguments: R1 already contains argc.
ASSERT(argv_offset == 2 * kWordSize);
// Set argv in NativeArguments: R2 already contains argv.
ASSERT(retval_offset == 3 * kWordSize);
// Set retval in NativeArgs.
__ add(R3, FP, Operand(kCallerSpSlotFromFp * kWordSize));
// Passing the structure by value as in runtime calls would require changing
// Dart API for native functions.
// For now, space is reserved on the stack and we pass a pointer to it.
__ stm(IA, SP, (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3));
__ mov(R0, Operand(SP)); // Pass the pointer to the NativeArguments.
__ mov(R1, Operand(R5)); // Pass the function entrypoint to call.
// Call native function invocation wrapper or redirection via simulator.
__ ldr(LR, Address(THR, Thread::native_call_wrapper_entry_point_offset()));
__ blx(LR);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(kWord, R2, THR, Thread::vm_tag_offset());
// Reset exit frame information in Isolate structure.
__ LoadImmediate(R2, 0);
__ StoreToOffset(kWord, R2, THR, Thread::top_exit_frame_info_offset());
__ LeaveStubFrame();
__ Ret();
}
// Input parameters:
// LR : return address.
// SP : address of return value.
// R5 : address of the native function to call.
// R2 : address of first argument in argument array.
// R1 : argc_tag including number of arguments and function kind.
void StubCode::GenerateCallBootstrapCFunctionStub(Assembler* assembler) {
const intptr_t thread_offset = NativeArguments::thread_offset();
const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
const intptr_t argv_offset = NativeArguments::argv_offset();
const intptr_t retval_offset = NativeArguments::retval_offset();
__ EnterStubFrame();
// Save exit frame information to enable stack walking as we are about
// to transition to native code.
__ StoreToOffset(kWord, FP, THR, Thread::top_exit_frame_info_offset());
#if defined(DEBUG)
{ Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(kWord, R6, THR, Thread::vm_tag_offset());
__ CompareImmediate(R6, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing native code.
__ StoreToOffset(kWord, R5, THR, Thread::vm_tag_offset());
// Reserve space for the native arguments structure passed on the stack (the
// outgoing pointer parameter to the native arguments structure is passed in
// R0) and align frame before entering the C++ world.
__ ReserveAlignedFrameSpace(sizeof(NativeArguments));
// Initialize NativeArguments structure and call native function.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * kWordSize);
// Set thread in NativeArgs.
__ mov(R0, Operand(THR));
// There are no native calls to closures, so we do not need to set the tag
// bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
ASSERT(argc_tag_offset == 1 * kWordSize);
// Set argc in NativeArguments: R1 already contains argc.
ASSERT(argv_offset == 2 * kWordSize);
// Set argv in NativeArguments: R2 already contains argv.
ASSERT(retval_offset == 3 * kWordSize);
// Set retval in NativeArgs.
__ add(R3, FP, Operand(kCallerSpSlotFromFp * kWordSize));
// Passing the structure by value as in runtime calls would require changing
// Dart API for native functions.
// For now, space is reserved on the stack and we pass a pointer to it.
__ stm(IA, SP, (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3));
__ mov(R0, Operand(SP)); // Pass the pointer to the NativeArguments.
// Call native function or redirection via simulator.
__ blx(R5);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(kWord, R2, THR, Thread::vm_tag_offset());
// Reset exit frame information in Isolate structure.
__ LoadImmediate(R2, 0);
__ StoreToOffset(kWord, R2, THR, Thread::top_exit_frame_info_offset());
__ LeaveStubFrame();
__ Ret();
}
// Input parameters:
// R4: arguments descriptor array.
void StubCode::GenerateCallStaticFunctionStub(Assembler* assembler) {
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value and preserve arguments descriptor.
__ LoadObject(R0, Object::null_object());
__ PushList((1 << R0) | (1 << R4));
__ CallRuntime(kPatchStaticCallRuntimeEntry, 0);
// Get Code object result and restore arguments descriptor array.
__ PopList((1 << R0) | (1 << R4));
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(R0, Code::entry_point_offset()));
__ bx(R0);
}
// Called from a static call only when an invalid code has been entered
// (invalid because its function was optimized or deoptimized).
// R4: arguments descriptor array.
void StubCode::GenerateFixCallersTargetStub(Assembler* assembler) {
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG, Address(THR, Thread::fix_callers_target_code_offset()));
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value and preserve arguments descriptor.
__ LoadObject(R0, Object::null_object());
__ PushList((1 << R0) | (1 << R4));
__ CallRuntime(kFixCallersTargetRuntimeEntry, 0);
// Get Code object result and restore arguments descriptor array.
__ PopList((1 << R0) | (1 << R4));
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(R0, Code::entry_point_offset()));
__ bx(R0);
}
// Called from object allocate instruction when the allocation stub has been
// disabled.
void StubCode::GenerateFixAllocationStubTargetStub(Assembler* assembler) {
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG, Address(THR, Thread::fix_allocation_stub_code_offset()));
__ EnterStubFrame();
// Setup space on stack for return value.
__ LoadObject(R0, Object::null_object());
__ Push(R0);
__ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
// Get Code object result.
__ Pop(R0);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(R0, Code::entry_point_offset()));
__ bx(R0);
}
// Input parameters:
// R2: smi-tagged argument count, may be zero.
// FP[kParamEndSlotFromFp + 1]: last argument.
static void PushArgumentsArray(Assembler* assembler) {
// Allocate array to store arguments of caller.
__ LoadObject(R1, Object::null_object());
// R1: null element type for raw Array.
// R2: smi-tagged argument count, may be zero.
__ BranchLink(*StubCode::AllocateArray_entry());
// R0: newly allocated array.
// R2: smi-tagged argument count, may be zero (was preserved by the stub).
__ Push(R0); // Array is in R0 and on top of stack.
__ AddImmediate(R1, FP, kParamEndSlotFromFp * kWordSize);
__ AddImmediate(R3, R0, Array::data_offset() - kHeapObjectTag);
// Copy arguments from stack to array (starting at the end).
// R1: address just beyond last argument on stack.
// R3: address of first argument in array.
Label enter;
__ b(&enter);
Label loop;
__ Bind(&loop);
__ ldr(IP, Address(R1, kWordSize, Address::PreIndex));
__ InitializeFieldNoBarrier(R0, Address(R3, R2, LSL, 1), IP);
__ Bind(&enter);
__ subs(R2, R2, Operand(Smi::RawValue(1))); // R2 is Smi.
__ b(&loop, PL);
}
// Used by eager and lazy deoptimization. Preserve result in R0 if necessary.
// This stub translates optimized frame into unoptimized frame. The optimized
// frame can contain values in registers and on stack, the unoptimized
// frame contains all values on stack.
// Deoptimization occurs in following steps:
// - Push all registers that can contain values.
// - Call C routine to copy the stack and saved registers into temporary buffer.
// - Adjust caller's frame to correct unoptimized frame size.
// - Fill the unoptimized frame.
// - Materialize objects that require allocation (e.g. Double instances).
// GC can occur only after frame is fully rewritten.
// Stack after EnterFrame(...) below:
// +------------------+
// | Saved PP | <- TOS
// +------------------+
// | Saved FP | <- FP of stub
// +------------------+
// | Saved LR | (deoptimization point)
// +------------------+
// | pc marker |
// +------------------+
// | Saved CODE_REG |
// +------------------+
// | ... | <- SP of optimized frame
//
// Parts of the code cannot GC, part of the code can GC.
static void GenerateDeoptimizationSequence(Assembler* assembler,
DeoptStubKind kind) {
// DeoptimizeCopyFrame expects a Dart frame, i.e. EnterDartFrame(0), but there
// is no need to set the correct PC marker or load PP, since they get patched.
// IP has the potentially live LR value. LR was clobbered by the call with
// the return address, so move it into IP to set up the Dart frame.
__ eor(IP, IP, Operand(LR));
__ eor(LR, IP, Operand(LR));
__ eor(IP, IP, Operand(LR));
// Set up the frame manually with return address now stored in IP.
__ EnterFrame((1 << PP) | (1 << CODE_REG) | (1 << FP) | (1 << IP), 0);
__ LoadPoolPointer();
// The code in this frame may not cause GC. kDeoptimizeCopyFrameRuntimeEntry
// and kDeoptimizeFillFrameRuntimeEntry are leaf runtime calls.
const intptr_t saved_result_slot_from_fp =
kFirstLocalSlotFromFp + 1 - (kNumberOfCpuRegisters - R0);
// Result in R0 is preserved as part of pushing all registers below.
// Push registers in their enumeration order: lowest register number at
// lowest address.
for (intptr_t i = kNumberOfCpuRegisters - 1; i >= 0; --i) {
if (i == CODE_REG) {
// Save the original value of CODE_REG pushed before invoking this stub
// instead of the value used to call this stub.
COMPILE_ASSERT(IP > CODE_REG); // Assert IP is pushed first.
__ ldr(IP, Address(FP, kCallerSpSlotFromFp * kWordSize));
__ Push(IP);
} else {
__ Push(static_cast<Register>(i));
}
}
if (TargetCPUFeatures::vfp_supported()) {
ASSERT(kFpuRegisterSize == 4 * kWordSize);
if (kNumberOfDRegisters > 16) {
__ vstmd(DB_W, SP, D16, kNumberOfDRegisters - 16);
__ vstmd(DB_W, SP, D0, 16);
} else {
__ vstmd(DB_W, SP, D0, kNumberOfDRegisters);
}
} else {
__ AddImmediate(SP, SP, -kNumberOfFpuRegisters * kFpuRegisterSize);
}
__ mov(R0, Operand(SP)); // Pass address of saved registers block.
__ mov(R1, Operand(kind == kLazyDeopt ? 1 : 0));
__ ReserveAlignedFrameSpace(0);
__ CallRuntime(kDeoptimizeCopyFrameRuntimeEntry, 2);
// Result (R0) is stack-size (FP - SP) in bytes.
const bool preserve_result = (kind == kLazyDeopt);
if (preserve_result) {
// Restore result into R1 temporarily.
__ ldr(R1, Address(FP, saved_result_slot_from_fp * kWordSize));
}
__ RestoreCodePointer();
__ LeaveDartFrame();
__ sub(SP, FP, Operand(R0));
// DeoptimizeFillFrame expects a Dart frame, i.e. EnterDartFrame(0), but there
// is no need to set the correct PC marker or load PP, since they get patched.
__ EnterStubFrame();
__ mov(R0, Operand(FP)); // Get last FP address.
if (preserve_result) {
__ Push(R1); // Preserve result as first local.
}
__ ReserveAlignedFrameSpace(0);
__ CallRuntime(kDeoptimizeFillFrameRuntimeEntry, 1); // Pass last FP in R0.
if (preserve_result) {
// Restore result into R1.
__ ldr(R1, Address(FP, kFirstLocalSlotFromFp * kWordSize));
}
// Code above cannot cause GC.
__ RestoreCodePointer();
__ LeaveStubFrame();
// Frame is fully rewritten at this point and it is safe to perform a GC.
// Materialize any objects that were deferred by FillFrame because they
// require allocation.
// Enter stub frame with loading PP. The caller's PP is not materialized yet.
__ EnterStubFrame();
if (preserve_result) {
__ Push(R1); // Preserve result, it will be GC-d here.
}
__ PushObject(Smi::ZoneHandle()); // Space for the result.
__ CallRuntime(kDeoptimizeMaterializeRuntimeEntry, 0);
// Result tells stub how many bytes to remove from the expression stack
// of the bottom-most frame. They were used as materialization arguments.
__ Pop(R1);
if (preserve_result) {
__ Pop(R0); // Restore result.
}
__ LeaveStubFrame();
// Remove materialization arguments.
__ add(SP, SP, Operand(R1, ASR, kSmiTagSize));
__ Ret();
}
void StubCode::GenerateDeoptimizeLazyStub(Assembler* assembler) {
// Correct return address to point just after the call that is being
// deoptimized.
__ AddImmediate(LR, -CallPattern::DeoptCallPatternLengthInBytes());
// Push zap value instead of CODE_REG for lazy deopt.
__ LoadImmediate(IP, 0xf1f1f1f1);
__ Push(IP);
GenerateDeoptimizationSequence(assembler, kLazyDeopt);
}
void StubCode::GenerateDeoptimizeStub(Assembler* assembler) {
GenerateDeoptimizationSequence(assembler, kEagerDeopt);
}
static void GenerateDispatcherCode(Assembler* assembler,
Label* call_target_function) {
__ Comment("NoSuchMethodDispatch");
// When lazily generated invocation dispatchers are disabled, the
// miss-handler may return null.
__ CompareObject(R0, Object::null_object());
__ b(call_target_function, NE);
__ EnterStubFrame();
// Load the receiver.
__ ldr(R2, FieldAddress(R4, ArgumentsDescriptor::count_offset()));
__ add(IP, FP, Operand(R2, LSL, 1)); // R2 is Smi.
__ ldr(R6, Address(IP, kParamEndSlotFromFp * kWordSize));
__ PushObject(Object::null_object());
__ Push(R6);
__ Push(R5);
__ Push(R4);
// R2: Smi-tagged arguments array length.
PushArgumentsArray(assembler);
const intptr_t kNumArgs = 4;
__ CallRuntime(kInvokeNoSuchMethodDispatcherRuntimeEntry, kNumArgs);
__ Drop(4);
__ Pop(R0); // Return value.
__ LeaveStubFrame();
__ Ret();
}
void StubCode::GenerateMegamorphicMissStub(Assembler* assembler) {
__ EnterStubFrame();
// Load the receiver.
__ ldr(R2, FieldAddress(R4, ArgumentsDescriptor::count_offset()));
__ add(IP, FP, Operand(R2, LSL, 1)); // R2 is Smi.
__ ldr(R6, Address(IP, kParamEndSlotFromFp * kWordSize));
// Preserve IC data and arguments descriptor.
__ PushList((1 << R4) | (1 << R5));
// Push space for the return value.
// Push the receiver.
// Push IC data object.
// Push arguments descriptor array.
__ LoadObject(IP, Object::null_object());
__ PushList((1 << R4) | (1 << R5) | (1 << R6) | (1 << IP));
__ CallRuntime(kMegamorphicCacheMissHandlerRuntimeEntry, 3);
// Remove arguments.
__ Drop(3);
__ Pop(R0); // Get result into R0 (target function).
// Restore IC data and arguments descriptor.
__ PopList((1 << R4) | (1 << R5));
__ RestoreCodePointer();
__ LeaveStubFrame();
if (!FLAG_lazy_dispatchers) {
Label call_target_function;
GenerateDispatcherCode(assembler, &call_target_function);
__ Bind(&call_target_function);
}
// Tail-call to target function.
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ ldr(R2, FieldAddress(R0, Function::entry_point_offset()));
__ bx(R2);
}
// Called for inline allocation of arrays.
// Input parameters:
// LR: return address.
// R1: array element type (either NULL or an instantiated type).
// R2: array length as Smi (must be preserved).
// The newly allocated object is returned in R0.
void StubCode::GenerateAllocateArrayStub(Assembler* assembler) {
Label slow_case;
// Compute the size to be allocated, it is based on the array length
// and is computed as:
// RoundedAllocationSize((array_length * kwordSize) + sizeof(RawArray)).
__ MoveRegister(R3, R2); // Array length.
// Check that length is a positive Smi.
__ tst(R3, Operand(kSmiTagMask));
if (FLAG_use_slow_path) {
__ b(&slow_case);
} else {
__ b(&slow_case, NE);
}
__ cmp(R3, Operand(0));
__ b(&slow_case, LT);
// Check for maximum allowed length.
const intptr_t max_len =
reinterpret_cast<int32_t>(Smi::New(Array::kMaxElements));
__ CompareImmediate(R3, max_len);
__ b(&slow_case, GT);
const intptr_t cid = kArrayCid;
__ MaybeTraceAllocation(cid, R4, &slow_case,
/* inline_isolate = */ false);
const intptr_t fixed_size = sizeof(RawArray) + kObjectAlignment - 1;
__ LoadImmediate(R5, fixed_size);
__ add(R5, R5, Operand(R3, LSL, 1)); // R3 is a Smi.
ASSERT(kSmiTagShift == 1);
__ bic(R5, R5, Operand(kObjectAlignment - 1));
// R5: Allocation size.
Heap::Space space = Heap::SpaceForAllocation(cid);
__ LoadIsolate(R6);
__ ldr(R6, Address(R6, Isolate::heap_offset()));
// Potential new object start.
__ ldr(R0, Address(R6, Heap::TopOffset(space)));
__ adds(R7, R0, Operand(R5)); // Potential next object start.
__ b(&slow_case, CS); // Branch if unsigned overflow.
// Check if the allocation fits into the remaining space.
// R0: potential new object start.
// R7: potential next object start.
// R5: allocation size.
__ ldr(R3, Address(R6, Heap::EndOffset(space)));
__ cmp(R7, Operand(R3));
__ b(&slow_case, CS);
// Successfully allocated the object(s), now update top to point to
// next object start and initialize the object.
__ LoadAllocationStatsAddress(R3, cid, /* inline_isolate = */ false);
__ str(R7, Address(R6, Heap::TopOffset(space)));
__ add(R0, R0, Operand(kHeapObjectTag));
// Initialize the tags.
// R0: new object start as a tagged pointer.
// R3: allocation stats address.
// R7: new object end address.
// R5: allocation size.
{
const intptr_t shift = RawObject::kSizeTagPos - kObjectAlignmentLog2;
__ CompareImmediate(R5, RawObject::SizeTag::kMaxSizeTag);
__ mov(R6, Operand(R5, LSL, shift), LS);
__ mov(R6, Operand(0), HI);
// Get the class index and insert it into the tags.
// R6: size and bit tags.
__ LoadImmediate(TMP, RawObject::ClassIdTag::encode(cid));
__ orr(R6, R6, Operand(TMP));
__ str(R6, FieldAddress(R0, Array::tags_offset())); // Store tags.
}
// R0: new object start as a tagged pointer.
// R7: new object end address.
// Store the type argument field.
__ InitializeFieldNoBarrier(R0,
FieldAddress(R0, Array::type_arguments_offset()),
R1);
// Set the length field.
__ InitializeFieldNoBarrier(R0,
FieldAddress(R0, Array::length_offset()),
R2);
// Initialize all array elements to raw_null.
// R0: new object start as a tagged pointer.
// R3: allocation stats address.
// R4, R5: null
// R6: iterator which initially points to the start of the variable
// data area to be initialized.
// R7: new object end address.
// R5: allocation size.
__ IncrementAllocationStatsWithSize(R3, R5, space);
__ LoadObject(R4, Object::null_object());
__ mov(R5, Operand(R4));
__ AddImmediate(R6, R0, sizeof(RawArray) - kHeapObjectTag);
__ InitializeFieldsNoBarrier(R0, R6, R7, R4, R5);
__ Ret(); // Returns the newly allocated object in R0.
// Unable to allocate the array using the fast inline code, just call
// into the runtime.
__ Bind(&slow_case);
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ LoadObject(IP, Object::null_object());
// Setup space on stack for return value.
// Push array length as Smi and element type.
__ PushList((1 << R1) | (1 << R2) | (1 << IP));
__ CallRuntime(kAllocateArrayRuntimeEntry, 2);
// Pop arguments; result is popped in IP.
__ PopList((1 << R1) | (1 << R2) | (1 << IP)); // R2 is restored.
__ mov(R0, Operand(IP));
__ LeaveStubFrame();
__ Ret();
}
// Called when invoking Dart code from C++ (VM code).
// Input parameters:
// LR : points to return address.
// R0 : code object of the Dart function to call.
// R1 : arguments descriptor array.
// R2 : arguments array.
// R3 : current thread.
void StubCode::GenerateInvokeDartCodeStub(Assembler* assembler) {
// Save frame pointer coming in.
__ EnterFrame((1 << FP) | (1 << LR), 0);
// Push code object to PC marker slot.
__ ldr(IP, Address(R3, Thread::invoke_dart_code_stub_offset()));
__ Push(IP);
// Save new context and C++ ABI callee-saved registers.
__ PushList(kAbiPreservedCpuRegs);
const DRegister firstd = EvenDRegisterOf(kAbiFirstPreservedFpuReg);
if (TargetCPUFeatures::vfp_supported()) {
ASSERT(2 * kAbiPreservedFpuRegCount < 16);
// Save FPU registers. 2 D registers per Q register.
__ vstmd(DB_W, SP, firstd, 2 * kAbiPreservedFpuRegCount);
} else {
__ sub(SP, SP, Operand(kAbiPreservedFpuRegCount * kFpuRegisterSize));
}
// Set up THR, which caches the current thread in Dart code.
if (THR != R3) {
__ mov(THR, Operand(R3));
}
// Save the current VMTag on the stack.
__ LoadFromOffset(kWord, R5, THR, Thread::vm_tag_offset());
__ Push(R5);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R5, VMTag::kDartTagId);
__ StoreToOffset(kWord, R5, THR, Thread::vm_tag_offset());
// Save top resource and top exit frame info. Use R4-6 as temporary registers.
// StackFrameIterator reads the top exit frame info saved in this frame.
__ LoadFromOffset(kWord, R5, THR, Thread::top_exit_frame_info_offset());
__ LoadFromOffset(kWord, R4, THR, Thread::top_resource_offset());
__ LoadImmediate(R6, 0);
__ StoreToOffset(kWord, R6, THR, Thread::top_resource_offset());
__ StoreToOffset(kWord, R6, THR, Thread::top_exit_frame_info_offset());
// kExitLinkSlotFromEntryFp must be kept in sync with the code below.
__ Push(R4);
ASSERT(kExitLinkSlotFromEntryFp == -27);
__ Push(R5);
// Load arguments descriptor array into R4, which is passed to Dart code.
__ ldr(R4, Address(R1, VMHandles::kOffsetOfRawPtrInHandle));
// Load number of arguments into R5.
__ ldr(R5, FieldAddress(R4, ArgumentsDescriptor::count_offset()));
__ SmiUntag(R5);
// Compute address of 'arguments array' data area into R2.
__ ldr(R2, Address(R2, VMHandles::kOffsetOfRawPtrInHandle));
__ AddImmediate(R2, R2, Array::data_offset() - kHeapObjectTag);
// Set up arguments for the Dart call.
Label push_arguments;
Label done_push_arguments;
__ CompareImmediate(R5, 0); // check if there are arguments.
__ b(&done_push_arguments, EQ);
__ LoadImmediate(R1, 0);
__ Bind(&push_arguments);
__ ldr(R3, Address(R2));
__ Push(R3);
__ AddImmediate(R2, kWordSize);
__ AddImmediate(R1, 1);
__ cmp(R1, Operand(R5));
__ b(&push_arguments, LT);
__ Bind(&done_push_arguments);
// Call the Dart code entrypoint.
__ LoadImmediate(PP, 0); // GC safe value into PP.
__ ldr(CODE_REG, Address(R0, VMHandles::kOffsetOfRawPtrInHandle));
__ ldr(R0, FieldAddress(CODE_REG, Code::entry_point_offset()));
__ blx(R0); // R4 is the arguments descriptor array.
// Get rid of arguments pushed on the stack.
__ AddImmediate(SP, FP, kExitLinkSlotFromEntryFp * kWordSize);
// Restore the saved top exit frame info and top resource back into the
// Isolate structure. Uses R5 as a temporary register for this.
__ Pop(R5);
__ StoreToOffset(kWord, R5, THR, Thread::top_exit_frame_info_offset());
__ Pop(R5);
__ StoreToOffset(kWord, R5, THR, Thread::top_resource_offset());
// Restore the current VMTag from the stack.
__ Pop(R4);
__ StoreToOffset(kWord, R4, THR, Thread::vm_tag_offset());
// Restore C++ ABI callee-saved registers.
if (TargetCPUFeatures::vfp_supported()) {
// Restore FPU registers. 2 D registers per Q register.
__ vldmd(IA_W, SP, firstd, 2 * kAbiPreservedFpuRegCount);
} else {
__ AddImmediate(SP, kAbiPreservedFpuRegCount * kFpuRegisterSize);
}
// Restore CPU registers.
__ PopList(kAbiPreservedCpuRegs);
__ set_constant_pool_allowed(false);
// Restore the frame pointer and return.
__ LeaveFrame((1 << FP) | (1 << LR));
__ Ret();
}
// Called for inline allocation of contexts.
// Input:
// R1: number of context variables.
// Output:
// R0: new allocated RawContext object.
void StubCode::GenerateAllocateContextStub(Assembler* assembler) {
if (FLAG_inline_alloc) {
Label slow_case;
// First compute the rounded instance size.
// R1: number of context variables.
intptr_t fixed_size = sizeof(RawContext) + kObjectAlignment - 1;
__ LoadImmediate(R2, fixed_size);
__ add(R2, R2, Operand(R1, LSL, 2));
ASSERT(kSmiTagShift == 1);
__ bic(R2, R2, Operand(kObjectAlignment - 1));
__ MaybeTraceAllocation(kContextCid, R4, &slow_case,
/* inline_isolate = */ false);
// Now allocate the object.
// R1: number of context variables.
// R2: object size.
const intptr_t cid = kContextCid;
Heap::Space space = Heap::SpaceForAllocation(cid);
__ LoadIsolate(R5);
__ ldr(R5, Address(R5, Isolate::heap_offset()));
__ ldr(R0, Address(R5, Heap::TopOffset(space)));
__ add(R3, R2, Operand(R0));
// Check if the allocation fits into the remaining space.
// R0: potential new object.
// R1: number of context variables.
// R2: object size.
// R3: potential next object start.
// R5: heap.
__ ldr(IP, Address(R5, Heap::EndOffset(space)));
__ cmp(R3, Operand(IP));
if (FLAG_use_slow_path) {
__ b(&slow_case);
} else {
__ b(&slow_case, CS); // Branch if unsigned higher or equal.
}
// Successfully allocated the object, now update top to point to
// next object start and initialize the object.
// R0: new object start (untagged).
// R1: number of context variables.
// R2: object size.
// R3: next object start.
// R5: heap.
__ LoadAllocationStatsAddress(R6, cid, /* inline_isolate = */ false);
__ str(R3, Address(R5, Heap::TopOffset(space)));
__ add(R0, R0, Operand(kHeapObjectTag));
// Calculate the size tag.
// R0: new object (tagged).
// R1: number of context variables.
// R2: object size.
// R3: next object start.
// R6: allocation stats address.
const intptr_t shift = RawObject::kSizeTagPos - kObjectAlignmentLog2;
__ CompareImmediate(R2, RawObject::SizeTag::kMaxSizeTag);
// If no size tag overflow, shift R2 left, else set R2 to zero.
__ mov(R5, Operand(R2, LSL, shift), LS);
__ mov(R5, Operand(0), HI);
// Get the class index and insert it into the tags.
// R5: size and bit tags.
__ LoadImmediate(IP, RawObject::ClassIdTag::encode(cid));
__ orr(R5, R5, Operand(IP));
__ str(R5, FieldAddress(R0, Context::tags_offset()));
// Setup up number of context variables field.
// R0: new object.
// R1: number of context variables as integer value (not object).
// R2: object size.
// R3: next object start.
// R6: allocation stats address.
__ str(R1, FieldAddress(R0, Context::num_variables_offset()));
// Setup the parent field.
// R0: new object.
// R1: number of context variables.
// R2: object size.
// R3: next object start.
// R6: allocation stats address.
__ LoadObject(R4, Object::null_object());
__ InitializeFieldNoBarrier(R0, FieldAddress(R0, Context::parent_offset()),
R4);
// Initialize the context variables.
// R0: new object.
// R1: number of context variables.
// R2: object size.
// R3: next object start.
// R4, R5: raw null.
// R6: allocation stats address.
Label loop;
__ AddImmediate(R7, R0, Context::variable_offset(0) - kHeapObjectTag);
__ InitializeFieldsNoBarrier(R0, R7, R3, R4, R5);
__ IncrementAllocationStatsWithSize(R6, R2, space);
// Done allocating and initializing the context.
// R0: new object.
__ Ret();
__ Bind(&slow_case);
}
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value.
__ LoadObject(R2, Object::null_object());
__ SmiTag(R1);
__ PushList((1 << R1) | (1 << R2));
__ CallRuntime(kAllocateContextRuntimeEntry, 1); // Allocate context.
__ Drop(1); // Pop number of context variables argument.
__ Pop(R0); // Pop the new context object.
// R0: new object
// Restore the frame pointer.
__ LeaveStubFrame();
__ Ret();
}
// Helper stub to implement Assembler::StoreIntoObject.
// Input parameters:
// R0: address (i.e. object) being stored into.
void StubCode::GenerateUpdateStoreBufferStub(Assembler* assembler) {
// Save values being destroyed.
__ PushList((1 << R1) | (1 << R2) | (1 << R3));
Label add_to_buffer;
// Check whether this object has already been remembered. Skip adding to the
// store buffer if the object is in the store buffer already.
// Spilled: R1, R2, R3
// R0: Address being stored
__ ldr(R2, FieldAddress(R0, Object::tags_offset()));
__ tst(R2, Operand(1 << RawObject::kRememberedBit));
__ b(&add_to_buffer, EQ);
__ PopList((1 << R1) | (1 << R2) | (1 << R3));
__ Ret();
__ Bind(&add_to_buffer);
// R2: Header word.
if (TargetCPUFeatures::arm_version() == ARMv5TE) {
// TODO(21263): Implement 'swp' and use it below.
#if !defined(USING_SIMULATOR)
ASSERT(OS::NumberOfAvailableProcessors() <= 1);
#endif
__ orr(R2, R2, Operand(1 << RawObject::kRememberedBit));
__ str(R2, FieldAddress(R0, Object::tags_offset()));
} else {
// Atomically set the remembered bit of the object header.
ASSERT(Object::tags_offset() == 0);
__ sub(R3, R0, Operand(kHeapObjectTag));
// R3: Untagged address of header word (ldrex/strex do not support offsets).
Label retry;
__ Bind(&retry);
__ ldrex(R2, R3);
__ orr(R2, R2, Operand(1 << RawObject::kRememberedBit));
__ strex(R1, R2, R3);
__ cmp(R1, Operand(1));
__ b(&retry, EQ);
}
// Load the StoreBuffer block out of the thread. Then load top_ out of the
// StoreBufferBlock and add the address to the pointers_.
__ ldr(R1, Address(THR, Thread::store_buffer_block_offset()));
__ ldr(R2, Address(R1, StoreBufferBlock::top_offset()));
__ add(R3, R1, Operand(R2, LSL, 2));
__ str(R0, Address(R3, StoreBufferBlock::pointers_offset()));
// Increment top_ and check for overflow.
// R2: top_.
// R1: StoreBufferBlock.
Label L;
__ add(R2, R2, Operand(1));
__ str(R2, Address(R1, StoreBufferBlock::top_offset()));
__ CompareImmediate(R2, StoreBufferBlock::kSize);
// Restore values.
__ PopList((1 << R1) | (1 << R2) | (1 << R3));
__ b(&L, EQ);
__ Ret();
// Handle overflow: Call the runtime leaf function.
__ Bind(&L);
// Setup frame, push callee-saved registers.
__ EnterCallRuntimeFrame(0 * kWordSize);
__ mov(R0, Operand(THR));
__ CallRuntime(kStoreBufferBlockProcessRuntimeEntry, 1);
// Restore callee-saved registers, tear down frame.
__ LeaveCallRuntimeFrame();
__ Ret();
}
// Called for inline allocation of objects.
// Input parameters:
// LR : return address.
// SP + 0 : type arguments object (only if class is parameterized).
void StubCode::GenerateAllocationStubForClass(Assembler* assembler,
const Class& cls) {
// Must load pool pointer before being able to patch.
Register new_pp = R7;
__ LoadPoolPointer(new_pp);
// The generated code is different if the class is parameterized.
const bool is_cls_parameterized = cls.NumTypeArguments() > 0;
ASSERT(!is_cls_parameterized ||
(cls.type_arguments_field_offset() != Class::kNoTypeArguments));
// kInlineInstanceSize is a constant used as a threshold for determining
// when the object initialization should be done as a loop or as
// straight line code.
const int kInlineInstanceSize = 12;
const intptr_t instance_size = cls.instance_size();
ASSERT(instance_size > 0);
Isolate* isolate = Isolate::Current();
if (FLAG_inline_alloc && Heap::IsAllocatableInNewSpace(instance_size) &&
!cls.TraceAllocation(isolate)) {
Label slow_case;
// Allocate the object and update top to point to
// next object start and initialize the allocated object.
Heap::Space space = Heap::SpaceForAllocation(cls.id());
__ ldr(R5, Address(THR, Thread::heap_offset()));
__ ldr(R0, Address(R5, Heap::TopOffset(space)));
__ AddImmediate(R1, R0, instance_size);
// Check if the allocation fits into the remaining space.
// R0: potential new object start.
// R1: potential next object start.
// R5: heap.
__ ldr(IP, Address(R5, Heap::EndOffset(space)));
__ cmp(R1, Operand(IP));
if (FLAG_use_slow_path) {
__ b(&slow_case);
} else {
__ b(&slow_case, CS); // Unsigned higher or equal.
}
__ str(R1, Address(R5, Heap::TopOffset(space)));
// Load the address of the allocation stats table. We split up the load
// and the increment so that the dependent load is not too nearby.
__ LoadAllocationStatsAddress(R5, cls.id(), /* inline_isolate = */ false);
// R0: new object start.
// R1: next object start.
// R5: allocation stats table.
// Set the tags.
uword tags = 0;
tags = RawObject::SizeTag::update(instance_size, tags);
ASSERT(cls.id() != kIllegalCid);
tags = RawObject::ClassIdTag::update(cls.id(), tags);
__ LoadImmediate(R2, tags);
__ str(R2, Address(R0, Instance::tags_offset()));
__ add(R0, R0, Operand(kHeapObjectTag));
// Initialize the remaining words of the object.
__ LoadObject(R2, Object::null_object());
// R2: raw null.
// R0: new object (tagged).
// R1: next object start.
// R5: allocation stats table.
// First try inlining the initialization without a loop.
if (instance_size < (kInlineInstanceSize * kWordSize)) {
// Small objects are initialized using a consecutive set of writes.
intptr_t begin_offset = Instance::NextFieldOffset() - kHeapObjectTag;
intptr_t end_offset = instance_size - kHeapObjectTag;
// Save one move if less than two fields.
if ((end_offset - begin_offset) >= (2 * kWordSize)) {
__ mov(R3, Operand(R2));
}
__ InitializeFieldsNoBarrierUnrolled(R0, R0, begin_offset, end_offset,
R2, R3);
} else {
// There are more than kInlineInstanceSize(12) fields
__ add(R4, R0, Operand(Instance::NextFieldOffset() - kHeapObjectTag));
__ mov(R3, Operand(R2));
// Loop until the whole object is initialized.
// R2: raw null.
// R3: raw null.
// R0: new object (tagged).
// R1: next object start.
// R4: next word to be initialized.
// R5: allocation stats table.
__ InitializeFieldsNoBarrier(R0, R4, R1, R2, R3);
}
if (is_cls_parameterized) {
// Set the type arguments in the new object.
__ ldr(R4, Address(SP, 0));
FieldAddress type_args(R0, cls.type_arguments_field_offset());
__ InitializeFieldNoBarrier(R0, type_args, R4);
}
// Done allocating and initializing the instance.
// R0: new object (tagged).
// R5: allocation stats table.
// Update allocation stats.
__ IncrementAllocationStats(R5, cls.id(), space);
// R0: new object (tagged).
__ Ret();
__ Bind(&slow_case);
}
if (is_cls_parameterized) {
// Load the type arguments.
__ ldr(R4, Address(SP, 0));
}
// If is_cls_parameterized:
// R4: new object type arguments.
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame(); // Uses pool pointer to pass cls to runtime.
__ LoadObject(R2, Object::null_object());
__ Push(R2); // Setup space on stack for return value.
__ PushObject(cls); // Push class of object to be allocated.
if (is_cls_parameterized) {
// Push type arguments.
__ Push(R4);
} else {
// Push null type arguments.
__ Push(R2);
}
__ CallRuntime(kAllocateObjectRuntimeEntry, 2); // Allocate object.
__ Drop(2); // Pop arguments.
__ Pop(R0); // Pop result (newly allocated object).
// R0: new object
// Restore the frame pointer.
__ LeaveStubFrame();
__ Ret();
}
// Called for invoking "dynamic noSuchMethod(Invocation invocation)" function
// from the entry code of a dart function after an error in passed argument
// name or number is detected.
// Input parameters:
// LR : return address.
// SP : address of last argument.
// R4: arguments descriptor array.
void StubCode::GenerateCallClosureNoSuchMethodStub(Assembler* assembler) {
__ EnterStubFrame();
// Load the receiver.
__ ldr(R2, FieldAddress(R4, ArgumentsDescriptor::count_offset()));
__ add(IP, FP, Operand(R2, LSL, 1)); // R2 is Smi.
__ ldr(R6, Address(IP, kParamEndSlotFromFp * kWordSize));
// Push space for the return value.
// Push the receiver.
// Push arguments descriptor array.
__ LoadObject(IP, Object::null_object());
__ PushList((1 << R4) | (1 << R6) | (1 << IP));
// R2: Smi-tagged arguments array length.
PushArgumentsArray(assembler);
const intptr_t kNumArgs = 3;
__ CallRuntime(kInvokeClosureNoSuchMethodRuntimeEntry, kNumArgs);
// noSuchMethod on closures always throws an error, so it will never return.
__ bkpt(0);
}
// R6: function object.
// R5: inline cache data object.
// Cannot use function object from ICData as it may be the inlined
// function and not the top-scope function.
void StubCode::GenerateOptimizedUsageCounterIncrement(Assembler* assembler) {
Register ic_reg = R5;
Register func_reg = R6;
if (FLAG_trace_optimized_ic_calls) {
__ EnterStubFrame();
__ PushList((1 << R5) | (1 << R6)); // Preserve.
__ Push(ic_reg); // Argument.
__ Push(func_reg); // Argument.
__ CallRuntime(kTraceICCallRuntimeEntry, 2);
__ Drop(2); // Discard argument;
__ PopList((1 << R5) | (1 << R6)); // Restore.
__ LeaveStubFrame();
}
__ ldr(R7, FieldAddress(func_reg, Function::usage_counter_offset()));
__ add(R7, R7, Operand(1));
__ str(R7, FieldAddress(func_reg, Function::usage_counter_offset()));
}
// Loads function into 'temp_reg'.
void StubCode::GenerateUsageCounterIncrement(Assembler* assembler,
Register temp_reg) {
if (FLAG_optimization_counter_threshold >= 0) {
Register ic_reg = R5;
Register func_reg = temp_reg;
ASSERT(temp_reg == R6);
__ Comment("Increment function counter");
__ ldr(func_reg, FieldAddress(ic_reg, ICData::owner_offset()));
__ ldr(R7, FieldAddress(func_reg, Function::usage_counter_offset()));
__ add(R7, R7, Operand(1));
__ str(R7, FieldAddress(func_reg, Function::usage_counter_offset()));
}
}
// Note: R5 must be preserved.
// Attempt a quick Smi operation for known operations ('kind'). The ICData
// must have been primed with a Smi/Smi check that will be used for counting
// the invocations.
static void EmitFastSmiOp(Assembler* assembler,
Token::Kind kind,
intptr_t num_args,
Label* not_smi_or_overflow) {
__ Comment("Fast Smi op");
__ ldr(R0, Address(SP, 0 * kWordSize));
__ ldr(R1, Address(SP, 1 * kWordSize));
__ orr(TMP, R0, Operand(R1));
__ tst(TMP, Operand(kSmiTagMask));
__ b(not_smi_or_overflow, NE);
switch (kind) {
case Token::kADD: {
__ adds(R0, R1, Operand(R0)); // Adds.
__ b(not_smi_or_overflow, VS); // Branch if overflow.
break;
}
case Token::kSUB: {
__ subs(R0, R1, Operand(R0)); // Subtract.
__ b(not_smi_or_overflow, VS); // Branch if overflow.
break;
}
case Token::kEQ: {
__ cmp(R0, Operand(R1));
__ LoadObject(R0, Bool::True(), EQ);
__ LoadObject(R0, Bool::False(), NE);
break;
}
default: UNIMPLEMENTED();
}
// R5: IC data object (preserved).
__ ldr(R6, FieldAddress(R5, ICData::ic_data_offset()));
// R6: ic_data_array with check entries: classes and target functions.
__ AddImmediate(R6, R6, Array::data_offset() - kHeapObjectTag);
// R6: points directly to the first ic data array element.
#if defined(DEBUG)
// Check that first entry is for Smi/Smi.
Label error, ok;
const intptr_t imm_smi_cid = reinterpret_cast<intptr_t>(Smi::New(kSmiCid));
__ ldr(R1, Address(R6, 0));
__ CompareImmediate(R1, imm_smi_cid);
__ b(&error, NE);
__ ldr(R1, Address(R6, kWordSize));
__ CompareImmediate(R1, imm_smi_cid);
__ b(&ok, EQ);
__ Bind(&error);
__ Stop("Incorrect IC data");
__ Bind(&ok);
#endif
if (FLAG_optimization_counter_threshold >= 0) {
// Update counter.
const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
__ LoadFromOffset(kWord, R1, R6, count_offset);
__ adds(R1, R1, Operand(Smi::RawValue(1)));
__ LoadImmediate(R1, Smi::RawValue(Smi::kMaxValue), VS); // Overflow.
__ StoreIntoSmiField(Address(R6, count_offset), R1);
}
__ Ret();
}
// Generate inline cache check for 'num_args'.
// LR: return address.
// R5: inline cache data object.
// Control flow:
// - If receiver is null -> jump to IC miss.
// - If receiver is Smi -> load Smi class.
// - If receiver is not-Smi -> load receiver's class.
// - Check if 'num_args' (including receiver) match any IC data group.
// - Match found -> jump to target.
// - Match not found -> jump to IC miss.
void StubCode::GenerateNArgsCheckInlineCacheStub(
Assembler* assembler,
intptr_t num_args,
const RuntimeEntry& handle_ic_miss,
Token::Kind kind,
RangeCollectionMode range_collection_mode,
bool optimized) {
__ CheckCodePointer();
ASSERT(num_args > 0);
#if defined(DEBUG)
{ Label ok;
// Check that the IC data array has NumArgsTested() == num_args.
// 'NumArgsTested' is stored in the least significant bits of 'state_bits'.
__ ldr(R6, FieldAddress(R5, ICData::state_bits_offset()));
ASSERT(ICData::NumArgsTestedShift() == 0); // No shift needed.
__ and_(R6, R6, Operand(ICData::NumArgsTestedMask()));
__ CompareImmediate(R6, num_args);
__ b(&ok, EQ);
__ Stop("Incorrect stub for IC data");
__ Bind(&ok);
}
#endif // DEBUG
Label stepping, done_stepping;
if (FLAG_support_debugger && !optimized) {
__ Comment("Check single stepping");
__ LoadIsolate(R6);
__ ldrb(R6, Address(R6, Isolate::single_step_offset()));
__ CompareImmediate(R6, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
}
__ Comment("Range feedback collection");
Label not_smi_or_overflow;
if (range_collection_mode == kCollectRanges) {
ASSERT((num_args == 1) || (num_args == 2));
if (num_args == 2) {
__ ldr(R0, Address(SP, 1 * kWordSize));
__ UpdateRangeFeedback(R0, 0, R5, R1, R4, &not_smi_or_overflow);
}
__ ldr(R0, Address(SP, 0 * kWordSize));
__ UpdateRangeFeedback(R0, num_args - 1, R5, R1, R4, &not_smi_or_overflow);
}
if (kind != Token::kILLEGAL) {
EmitFastSmiOp(assembler, kind, num_args, &not_smi_or_overflow);
}
__ Bind(&not_smi_or_overflow);
__ Comment("Extract ICData initial values and receiver cid");
// Load arguments descriptor into R4.
__ ldr(R4, FieldAddress(R5, ICData::arguments_descriptor_offset()));
// Loop that checks if there is an IC data match.
Label loop, update, test, found;
// R5: IC data object (preserved).
__ ldr(R6, FieldAddress(R5, ICData::ic_data_offset()));
// R6: ic_data_array with check entries: classes and target functions.
__ AddImmediate(R6, R6, Array::data_offset() - kHeapObjectTag);
// R6: points directly to the first ic data array element.
// Get the receiver's class ID (first read number of arguments from
// arguments descriptor array and then access the receiver from the stack).
__ ldr(R7, FieldAddress(R4, ArgumentsDescriptor::count_offset()));
__ sub(R7, R7, Operand(Smi::RawValue(1)));
__ ldr(R0, Address(SP, R7, LSL, 1)); // R7 (argument_count - 1) is smi.
__ LoadTaggedClassIdMayBeSmi(R0, R0);
// R7: argument_count - 1 (smi).
// R0: receiver's class ID (smi).
__ ldr(R1, Address(R6, 0)); // First class id (smi) to check.
__ b(&test);
__ Comment("ICData loop");
__ Bind(&loop);
for (int i = 0; i < num_args; i++) {
if (i > 0) {
// If not the first, load the next argument's class ID.
__ AddImmediate(R0, R7, Smi::RawValue(-i));
__ ldr(R0, Address(SP, R0, LSL, 1));
__ LoadTaggedClassIdMayBeSmi(R0, R0);
// R0: next argument class ID (smi).
__ LoadFromOffset(kWord, R1, R6, i * kWordSize);
// R1: next class ID to check (smi).
}
__ cmp(R0, Operand(R1)); // Class id match?
if (i < (num_args - 1)) {
__ b(&update, NE); // Continue.
} else {
// Last check, all checks before matched.
__ b(&found, EQ); // Break.
}
}
__ Bind(&update);
// Reload receiver class ID. It has not been destroyed when num_args == 1.
if (num_args > 1) {
__ ldr(R0, Address(SP, R7, LSL, 1));
__ LoadTaggedClassIdMayBeSmi(R0, R0);
}
const intptr_t entry_size = ICData::TestEntryLengthFor(num_args) * kWordSize;
__ AddImmediate(R6, entry_size); // Next entry.
__ ldr(R1, Address(R6, 0)); // Next class ID.
__ Bind(&test);
__ CompareImmediate(R1, Smi::RawValue(kIllegalCid)); // Done?
__ b(&loop, NE);
__ Comment("IC miss");
// Compute address of arguments.
// R7: argument_count - 1 (smi).
__ add(R7, SP, Operand(R7, LSL, 1)); // R7 is Smi.
// R7: address of receiver.
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ LoadObject(R0, Object::null_object());
// Preserve IC data object and arguments descriptor array and
// setup space on stack for result (target code object).
__ PushList((1 << R0) | (1 << R4) | (1 << R5));
// Push call arguments.
for (intptr_t i = 0; i < num_args; i++) {
__ LoadFromOffset(kWord, IP, R7, -i * kWordSize);
__ Push(IP);
}
// Pass IC data object.
__ Push(R5);
__ CallRuntime(handle_ic_miss, num_args + 1);
// Remove the call arguments pushed earlier, including the IC data object.
__ Drop(num_args + 1);
// Pop returned function object into R0.
// Restore arguments descriptor array and IC data array.
__ PopList((1 << R0) | (1 << R4) | (1 << R5));
if (range_collection_mode == kCollectRanges) {
__ RestoreCodePointer();
}
__ LeaveStubFrame();
Label call_target_function;
if (!FLAG_lazy_dispatchers) {
GenerateDispatcherCode(assembler, &call_target_function);
} else {
__ b(&call_target_function);
}
__ Bind(&found);
// R6: pointer to an IC data check group.
const intptr_t target_offset = ICData::TargetIndexFor(num_args) * kWordSize;
const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
__ LoadFromOffset(kWord, R0, R6, target_offset);
if (FLAG_optimization_counter_threshold >= 0) {
__ Comment("Update caller's counter");
__ LoadFromOffset(kWord, R1, R6, count_offset);
__ adds(R1, R1, Operand(Smi::RawValue(1)));
__ LoadImmediate(R1, Smi::RawValue(Smi::kMaxValue), VS); // Overflow.
__ StoreIntoSmiField(Address(R6, count_offset), R1);
}
__ Comment("Call target");
__ Bind(&call_target_function);
// R0: target function.
__ ldr(R2, FieldAddress(R0, Function::entry_point_offset()));
if (range_collection_mode == kCollectRanges) {
__ ldr(R1, Address(SP, 0 * kWordSize));
if (num_args == 2) {
__ ldr(R3, Address(SP, 1 * kWordSize));
}
__ EnterStubFrame();
if (num_args == 2) {
__ PushList((1 << R1) | (1 << R3) | (1 << R5));
} else {
__ PushList((1 << R1) | (1 << R5));
}
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ blx(R2);
Label done;
__ ldr(R5, Address(FP, kFirstLocalSlotFromFp * kWordSize));
__ UpdateRangeFeedback(R0, 2, R5, R1, R4, &done);
__ Bind(&done);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ Ret();
} else {
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ bx(R2);
}
if (FLAG_support_debugger && !optimized) {
__ Bind(&stepping);
__ EnterStubFrame();
__ Push(R5); // Preserve IC data.
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ Pop(R5);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
}
}
// Use inline cache data array to invoke the target or continue in inline
// cache miss handler. Stub for 1-argument check (receiver class).
// LR: return address.
// R5: inline cache data object.
// Inline cache data object structure:
// 0: function-name
// 1: N, number of arguments checked.
// 2 .. (length - 1): group of checks, each check containing:
// - N classes.
// - 1 target function.
void StubCode::GenerateOneArgCheckInlineCacheStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler,
1,
kInlineCacheMissHandlerOneArgRuntimeEntry,
Token::kILLEGAL,
kIgnoreRanges);
}
void StubCode::GenerateTwoArgsCheckInlineCacheStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler,
2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry,
Token::kILLEGAL,
kIgnoreRanges);
}
void StubCode::GenerateSmiAddInlineCacheStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler,
2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry,
Token::kADD,
kCollectRanges);
}
void StubCode::GenerateSmiSubInlineCacheStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler, 2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kSUB,
kCollectRanges);
}
void StubCode::GenerateSmiEqualInlineCacheStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler, 2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kEQ,
kIgnoreRanges);
}
void StubCode::GenerateUnaryRangeCollectingInlineCacheStub(
Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler, 1,
kInlineCacheMissHandlerOneArgRuntimeEntry,
Token::kILLEGAL,
kCollectRanges);
}
void StubCode::GenerateBinaryRangeCollectingInlineCacheStub(
Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler, 2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry,
Token::kILLEGAL,
kCollectRanges);
}
void StubCode::GenerateOneArgOptimizedCheckInlineCacheStub(
Assembler* assembler) {
GenerateOptimizedUsageCounterIncrement(assembler);
GenerateNArgsCheckInlineCacheStub(assembler, 1,
kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kIgnoreRanges, true /* optimized */);
}
void StubCode::GenerateTwoArgsOptimizedCheckInlineCacheStub(
Assembler* assembler) {
GenerateOptimizedUsageCounterIncrement(assembler);
GenerateNArgsCheckInlineCacheStub(assembler, 2,
kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kIgnoreRanges, true /* optimized */);
}
// Intermediary stub between a static call and its target. ICData contains
// the target function and the call count.
// R5: ICData
void StubCode::GenerateZeroArgsUnoptimizedStaticCallStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
#if defined(DEBUG)
{ Label ok;
// Check that the IC data array has NumArgsTested() == 0.
// 'NumArgsTested' is stored in the least significant bits of 'state_bits'.
__ ldr(R6, FieldAddress(R5, ICData::state_bits_offset()));
ASSERT(ICData::NumArgsTestedShift() == 0); // No shift needed.
__ and_(R6, R6, Operand(ICData::NumArgsTestedMask()));
__ CompareImmediate(R6, 0);
__ b(&ok, EQ);
__ Stop("Incorrect IC data for unoptimized static call");
__ Bind(&ok);
}
#endif // DEBUG
// Check single stepping.
Label stepping, done_stepping;
if (FLAG_support_debugger) {
__ LoadIsolate(R6);
__ ldrb(R6, Address(R6, Isolate::single_step_offset()));
__ CompareImmediate(R6, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
}
// R5: IC data object (preserved).
__ ldr(R6, FieldAddress(R5, ICData::ic_data_offset()));
// R6: ic_data_array with entries: target functions and count.
__ AddImmediate(R6, R6, Array::data_offset() - kHeapObjectTag);
// R6: points directly to the first ic data array element.
const intptr_t target_offset = ICData::TargetIndexFor(0) * kWordSize;
const intptr_t count_offset = ICData::CountIndexFor(0) * kWordSize;
if (FLAG_optimization_counter_threshold >= 0) {
// Increment count for this call.
__ LoadFromOffset(kWord, R1, R6, count_offset);
__ adds(R1, R1, Operand(Smi::RawValue(1)));
__ LoadImmediate(R1, Smi::RawValue(Smi::kMaxValue), VS); // Overflow.
__ StoreIntoSmiField(Address(R6, count_offset), R1);
}
// Load arguments descriptor into R4.
__ ldr(R4, FieldAddress(R5, ICData::arguments_descriptor_offset()));
// Get function and call it, if possible.
__ LoadFromOffset(kWord, R0, R6, target_offset);
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ ldr(R2, FieldAddress(R0, Function::entry_point_offset()));
__ bx(R2);
if (FLAG_support_debugger) {
__ Bind(&stepping);
__ EnterStubFrame();
__ Push(R5); // Preserve IC data.
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ Pop(R5);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
}
}
void StubCode::GenerateOneArgUnoptimizedStaticCallStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(
assembler, 1, kStaticCallMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kIgnoreRanges);
}
void StubCode::GenerateTwoArgsUnoptimizedStaticCallStub(Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, R6);
GenerateNArgsCheckInlineCacheStub(assembler, 2,
kStaticCallMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kIgnoreRanges);
}
// Stub for compiling a function and jumping to the compiled code.
// R5: IC-Data (for methods).
// R4: Arguments descriptor.
// R0: Function.
void StubCode::GenerateLazyCompileStub(Assembler* assembler) {
// Preserve arg desc. and IC data object.
__ EnterStubFrame();
__ PushList((1 << R4) | (1 << R5));
__ Push(R0); // Pass function.
__ CallRuntime(kCompileFunctionRuntimeEntry, 1);
__ Pop(R0); // Restore argument.
__ PopList((1 << R4) | (1 << R5)); // Restore arg desc. and IC data.
__ LeaveStubFrame();
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ ldr(R2, FieldAddress(R0, Function::entry_point_offset()));
__ bx(R2);
}
// R5: Contains an ICData.
void StubCode::GenerateICCallBreakpointStub(Assembler* assembler) {
__ EnterStubFrame();
__ LoadObject(R0, Object::null_object());
// Preserve arguments descriptor and make room for result.
__ PushList((1 << R0) | (1 << R5));
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ PopList((1 << R0) | (1 << R5));
__ LeaveStubFrame();
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(CODE_REG, Code::entry_point_offset()));
__ bx(R0);
}
void StubCode::GenerateRuntimeCallBreakpointStub(Assembler* assembler) {
__ EnterStubFrame();
__ LoadObject(R0, Object::null_object());
// Make room for result.
__ PushList((1 << R0));
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ PopList((1 << CODE_REG));
__ LeaveStubFrame();
__ ldr(R0, FieldAddress(CODE_REG, Code::entry_point_offset()));
__ bx(R0);
}
// Called only from unoptimized code. All relevant registers have been saved.
void StubCode::GenerateDebugStepCheckStub(
Assembler* assembler) {
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(R1);
__ ldrb(R1, Address(R1, Isolate::single_step_offset()));
__ CompareImmediate(R1, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
__ Ret();
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ LeaveStubFrame();
__ b(&done_stepping);
}
// Used to check class and type arguments. Arguments passed in registers:
// LR: return address.
// R0: instance (must be preserved).
// R1: instantiator type arguments or NULL.
// R2: cache array.
// Result in R1: null -> not found, otherwise result (true or false).
static void GenerateSubtypeNTestCacheStub(Assembler* assembler, int n) {
ASSERT((1 <= n) && (n <= 3));
if (n > 1) {
// Get instance type arguments.
__ LoadClass(R3, R0, R4);
// Compute instance type arguments into R4.
Label has_no_type_arguments;
__ LoadObject(R4, Object::null_object());
__ ldr(R5, FieldAddress(R3,
Class::type_arguments_field_offset_in_words_offset()));
__ CompareImmediate(R5, Class::kNoTypeArguments);
__ b(&has_no_type_arguments, EQ);
__ add(R5, R0, Operand(R5, LSL, 2));
__ ldr(R4, FieldAddress(R5, 0));
__ Bind(&has_no_type_arguments);
}
__ LoadClassId(R3, R0);
// R0: instance.
// R1: instantiator type arguments or NULL.
// R2: SubtypeTestCache.
// R3: instance class id.
// R4: instance type arguments (null if none), used only if n > 1.
__ ldr(R2, FieldAddress(R2, SubtypeTestCache::cache_offset()));
__ AddImmediate(R2, Array::data_offset() - kHeapObjectTag);
Label loop, found, not_found, next_iteration;
// R2: entry start.
// R3: instance class id.
// R4: instance type arguments.
__ SmiTag(R3);
__ Bind(&loop);
__ ldr(R5, Address(R2, kWordSize * SubtypeTestCache::kInstanceClassId));
__ CompareObject(R5, Object::null_object());
__ b(&not_found, EQ);
__ cmp(R5, Operand(R3));
if (n == 1) {
__ b(&found, EQ);
} else {
__ b(&next_iteration, NE);
__ ldr(R5,
Address(R2, kWordSize * SubtypeTestCache::kInstanceTypeArguments));
__ cmp(R5, Operand(R4));
if (n == 2) {
__ b(&found, EQ);
} else {
__ b(&next_iteration, NE);
__ ldr(R5, Address(R2, kWordSize *
SubtypeTestCache::kInstantiatorTypeArguments));
__ cmp(R5, Operand(R1));
__ b(&found, EQ);
}
}
__ Bind(&next_iteration);
__ AddImmediate(R2, kWordSize * SubtypeTestCache::kTestEntryLength);
__ b(&loop);
// Fall through to not found.
__ Bind(&not_found);
__ LoadObject(R1, Object::null_object());
__ Ret();
__ Bind(&found);
__ ldr(R1, Address(R2, kWordSize * SubtypeTestCache::kTestResult));
__ Ret();
}
// Used to check class and type arguments. Arguments passed in registers:
// LR: return address.
// R0: instance (must be preserved).
// R1: instantiator type arguments or NULL.
// R2: cache array.
// Result in R1: null -> not found, otherwise result (true or false).
void StubCode::GenerateSubtype1TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 1);
}
// Used to check class and type arguments. Arguments passed in registers:
// LR: return address.
// R0: instance (must be preserved).
// R1: instantiator type arguments or NULL.
// R2: cache array.
// Result in R1: null -> not found, otherwise result (true or false).
void StubCode::GenerateSubtype2TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 2);
}
// Used to check class and type arguments. Arguments passed in registers:
// LR: return address.
// R0: instance (must be preserved).
// R1: instantiator type arguments or NULL.
// R2: cache array.
// Result in R1: null -> not found, otherwise result (true or false).
void StubCode::GenerateSubtype3TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 3);
}
// Return the current stack pointer address, used to do stack alignment checks.
void StubCode::GenerateGetStackPointerStub(Assembler* assembler) {
__ mov(R0, Operand(SP));
__ Ret();
}
// Jump to the exception or error handler.
// LR: return address.
// R0: program_counter.
// R1: stack_pointer.
// R2: frame_pointer.
// R3: error object.
// SP + 0: address of stacktrace object.
// SP + 4: thread.
// Does not return.
void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
ASSERT(kExceptionObjectReg == R0);
ASSERT(kStackTraceObjectReg == R1);
__ mov(IP, Operand(R1)); // Copy Stack pointer into IP.
__ mov(LR, Operand(R0)); // Program counter.
__ mov(R0, Operand(R3)); // Exception object.
__ ldr(R1, Address(SP, 0)); // StackTrace object.
__ ldr(THR, Address(SP, 4)); // Thread.
__ mov(FP, Operand(R2)); // Frame_pointer.
__ mov(SP, Operand(IP)); // Set Stack pointer.
// Set the tag.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(kWord, R2, THR, Thread::vm_tag_offset());
// Clear top exit frame.
__ LoadImmediate(R2, 0);
__ StoreToOffset(kWord, R2, THR, Thread::top_exit_frame_info_offset());
__ bx(LR); // Jump to the exception handler code.
}
// Calls to the runtime to optimize the given function.
// R6: function to be reoptimized.
// R4: argument descriptor (preserved).
void StubCode::GenerateOptimizeFunctionStub(Assembler* assembler) {
__ EnterStubFrame();
__ Push(R4);
__ LoadObject(IP, Object::null_object());
__ Push(IP); // Setup space on stack for return value.
__ Push(R6);
__ CallRuntime(kOptimizeInvokedFunctionRuntimeEntry, 1);
__ Pop(R0); // Discard argument.
__ Pop(R0); // Get Code object
__ Pop(R4); // Restore argument descriptor.
__ LeaveStubFrame();
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(R0, Code::entry_point_offset()));
__ bx(R0);
__ bkpt(0);
}
// Does identical check (object references are equal or not equal) with special
// checks for boxed numbers.
// LR: return address.
// Return Zero condition flag set if equal.
// Note: A Mint cannot contain a value that would fit in Smi, a Bigint
// cannot contain a value that fits in Mint or Smi.
static void GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
const Register left,
const Register right,
const Register temp) {
Label reference_compare, done, check_mint, check_bigint;
// If any of the arguments is Smi do reference compare.
__ tst(left, Operand(kSmiTagMask));
__ b(&reference_compare, EQ);
__ tst(right, Operand(kSmiTagMask));
__ b(&reference_compare, EQ);
// Value compare for two doubles.
__ CompareClassId(left, kDoubleCid, temp);
__ b(&check_mint, NE);
__ CompareClassId(right, kDoubleCid, temp);
__ b(&done, NE);
// Double values bitwise compare.
__ ldr(temp, FieldAddress(left, Double::value_offset() + 0 * kWordSize));
__ ldr(IP, FieldAddress(right, Double::value_offset() + 0 * kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done, NE);
__ ldr(temp, FieldAddress(left, Double::value_offset() + 1 * kWordSize));
__ ldr(IP, FieldAddress(right, Double::value_offset() + 1 * kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done);
__ Bind(&check_mint);
__ CompareClassId(left, kMintCid, temp);
__ b(&check_bigint, NE);
__ CompareClassId(right, kMintCid, temp);
__ b(&done, NE);
__ ldr(temp, FieldAddress(left, Mint::value_offset() + 0 * kWordSize));
__ ldr(IP, FieldAddress(right, Mint::value_offset() + 0 * kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done, NE);
__ ldr(temp, FieldAddress(left, Mint::value_offset() + 1 * kWordSize));
__ ldr(IP, FieldAddress(right, Mint::value_offset() + 1 * kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done);
__ Bind(&check_bigint);
__ CompareClassId(left, kBigintCid, temp);
__ b(&reference_compare, NE);
__ CompareClassId(right, kBigintCid, temp);
__ b(&done, NE);
__ EnterStubFrame();
__ ReserveAlignedFrameSpace(2 * kWordSize);
__ stm(IA, SP, (1 << R0) | (1 << R1));
__ CallRuntime(kBigintCompareRuntimeEntry, 2);
// Result in R0, 0 means equal.
__ LeaveStubFrame();
__ cmp(R0, Operand(0));
__ b(&done);
__ Bind(&reference_compare);
__ cmp(left, Operand(right));
__ Bind(&done);
}
// Called only from unoptimized code. All relevant registers have been saved.
// LR: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return Zero condition flag set if equal.
void StubCode::GenerateUnoptimizedIdenticalWithNumberCheckStub(
Assembler* assembler) {
// Check single stepping.
Label stepping, done_stepping;
if (FLAG_support_debugger) {
__ LoadIsolate(R1);
__ ldrb(R1, Address(R1, Isolate::single_step_offset()));
__ CompareImmediate(R1, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
}
const Register temp = R2;
const Register left = R1;
const Register right = R0;
__ ldr(left, Address(SP, 1 * kWordSize));
__ ldr(right, Address(SP, 0 * kWordSize));
GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
__ Ret();
if (FLAG_support_debugger) {
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
}
}
// Called from optimized code only.
// LR: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return Zero condition flag set if equal.
void StubCode::GenerateOptimizedIdenticalWithNumberCheckStub(
Assembler* assembler) {
const Register temp = R2;
const Register left = R1;
const Register right = R0;
__ ldr(left, Address(SP, 1 * kWordSize));
__ ldr(right, Address(SP, 0 * kWordSize));
GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
__ Ret();
}
void StubCode::EmitMegamorphicLookup(
Assembler* assembler, Register receiver, Register cache, Register target) {
ASSERT((cache != R0) && (cache != R2));
__ LoadTaggedClassIdMayBeSmi(R0, receiver);
// R0: class ID of the receiver (smi).
__ ldr(R2, FieldAddress(cache, MegamorphicCache::buckets_offset()));
__ ldr(R1, FieldAddress(R1, MegamorphicCache::mask_offset()));
// R2: cache buckets array.
// R1: mask.
__ mov(R3, Operand(R0));
Label loop, update, call_target_function;
__ b(&loop);
__ Bind(&update);
__ add(R3, R3, Operand(Smi::RawValue(1)));
__ Bind(&loop);
__ and_(R3, R3, Operand(R1));
const intptr_t base = Array::data_offset();
// R3 is smi tagged, but table entries are two words, so LSL 2.
__ add(IP, R2, Operand(R3, LSL, 2));
__ ldr(R4, FieldAddress(IP, base));
ASSERT(kIllegalCid == 0);
__ tst(R4, Operand(R4));
__ b(&call_target_function, EQ);
__ cmp(R4, Operand(R0));
__ b(&update, NE);
__ Bind(&call_target_function);
// Call the target found in the cache. For a class id match, this is a
// proper target for the given name and arguments descriptor. If the
// illegal class id was found, the target is a cache miss handler that can
// be invoked as a normal Dart function.
__ add(IP, R2, Operand(R3, LSL, 2));
__ ldr(R0, FieldAddress(IP, base + kWordSize));
__ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
__ ldr(target, FieldAddress(R0, Function::entry_point_offset()));
}
// Called from megamorphic calls.
// R0: receiver.
// R1: lookup cache.
// Result:
// R1: entry point.
void StubCode::GenerateMegamorphicLookupStub(Assembler* assembler) {
EmitMegamorphicLookup(assembler, R0, R1, R1);
__ Ret();
}
} // namespace dart
#endif // defined TARGET_ARCH_ARM