Reset trunk to 3.24.35.4

src/a64/deoptimizer-a64.cc

-// Copyright 2013 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"
-
-#include "codegen.h"
-#include "deoptimizer.h"
-#include "full-codegen.h"
-#include "safepoint-table.h"
-
-
-namespace v8 {
-namespace internal {
-
-
-int Deoptimizer::patch_size() {
-  // Size of the code used to patch lazy bailout points.
-  // Patching is done by Deoptimizer::DeoptimizeFunction.
-  return 4 * kInstructionSize;
-}
-
-
-
-void Deoptimizer::PatchCodeForDeoptimization(Isolate* isolate, Code* code) {
-  // Invalidate the relocation information, as it will become invalid by the
-  // code patching below, and is not needed any more.
-  code->InvalidateRelocation();
-
-  // For each LLazyBailout instruction insert a call to the corresponding
-  // deoptimization entry.
-  DeoptimizationInputData* deopt_data =
-      DeoptimizationInputData::cast(code->deoptimization_data());
-  Address code_start_address = code->instruction_start();
-#ifdef DEBUG
-  Address prev_call_address = NULL;
-#endif
-
-  for (int i = 0; i < deopt_data->DeoptCount(); i++) {
-    if (deopt_data->Pc(i)->value() == -1) continue;
-
-    Address call_address = code_start_address + deopt_data->Pc(i)->value();
-    Address deopt_entry = GetDeoptimizationEntry(isolate, i, LAZY);
-
-    PatchingAssembler patcher(call_address, patch_size() / kInstructionSize);
-    patcher.LoadLiteral(ip0, 2 * kInstructionSize);
-    patcher.blr(ip0);
-    patcher.dc64(reinterpret_cast<intptr_t>(deopt_entry));
-
-    ASSERT((prev_call_address == NULL) ||
-           (call_address >= prev_call_address + patch_size()));
-    ASSERT(call_address + patch_size() <= code->instruction_end());
-#ifdef DEBUG
-    prev_call_address = call_address;
-#endif
-  }
-}
-
-
-void Deoptimizer::FillInputFrame(Address tos, JavaScriptFrame* frame) {
-  // Set the register values. The values are not important as there are no
-  // callee saved registers in JavaScript frames, so all registers are
-  // spilled. Registers fp and sp are set to the correct values though.
-  for (int i = 0; i < Register::NumRegisters(); i++) {
-    input_->SetRegister(i, 0);
-  }
-
-  // TODO(all): Do we also need to set a value to csp?
-  input_->SetRegister(jssp.code(), reinterpret_cast<intptr_t>(frame->sp()));
-  input_->SetRegister(fp.code(), reinterpret_cast<intptr_t>(frame->fp()));
-
-  for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); i++) {
-    input_->SetDoubleRegister(i, 0.0);
-  }
-
-  // Fill the frame content from the actual data on the frame.
-  for (unsigned i = 0; i < input_->GetFrameSize(); i += kPointerSize) {
-    input_->SetFrameSlot(i, Memory::uint64_at(tos + i));
-  }
-}
-
-
-bool Deoptimizer::HasAlignmentPadding(JSFunction* function) {
-  // There is no dynamic alignment padding on A64 in the input frame.
-  return false;
-}
-
-
-void Deoptimizer::SetPlatformCompiledStubRegisters(
-    FrameDescription* output_frame, CodeStubInterfaceDescriptor* descriptor) {
-  ApiFunction function(descriptor->deoptimization_handler_);
-  ExternalReference xref(&function, ExternalReference::BUILTIN_CALL, isolate_);
-  intptr_t handler = reinterpret_cast<intptr_t>(xref.address());
-  int params = descriptor->GetHandlerParameterCount();
-  output_frame->SetRegister(x0.code(), params);
-  output_frame->SetRegister(x1.code(), handler);
-}
-
-
-void Deoptimizer::CopyDoubleRegisters(FrameDescription* output_frame) {
-  for (int i = 0; i < DoubleRegister::kMaxNumRegisters; ++i) {
-    double double_value = input_->GetDoubleRegister(i);
-    output_frame->SetDoubleRegister(i, double_value);
-  }
-}
-
-
-Code* Deoptimizer::NotifyStubFailureBuiltin() {
-  return isolate_->builtins()->builtin(Builtins::kNotifyStubFailureSaveDoubles);
-}
-
-
-#define __ masm()->
-
-void Deoptimizer::EntryGenerator::Generate() {
-  GeneratePrologue();
-
-  // TODO(all): This code needs to be revisited. We probably only need to save
-  // caller-saved registers here. Callee-saved registers can be stored directly
-  // in the input frame.
-
-  // Save all allocatable floating point registers.
-  CPURegList saved_fp_registers(CPURegister::kFPRegister, kDRegSize,
-                                0, FPRegister::NumAllocatableRegisters() - 1);
-  __ PushCPURegList(saved_fp_registers);
-
-  // We save all the registers expcept jssp, sp and lr.
-  CPURegList saved_registers(CPURegister::kRegister, kXRegSize, 0, 27);
-  saved_registers.Combine(fp);
-  __ PushCPURegList(saved_registers);
-
-  const int kSavedRegistersAreaSize =
-      (saved_registers.Count() * kXRegSizeInBytes) +
-      (saved_fp_registers.Count() * kDRegSizeInBytes);
-
-  // Floating point registers are saved on the stack above core registers.
-  const int kFPRegistersOffset = saved_registers.Count() * kXRegSizeInBytes;
-
-  // Get the bailout id from the stack.
-  Register bailout_id = x2;
-  __ Peek(bailout_id, kSavedRegistersAreaSize);
-
-  Register code_object = x3;
-  Register fp_to_sp = x4;
-  // Get the address of the location in the code object. This is the return
-  // address for lazy deoptimization.
-  __ Mov(code_object, lr);
-  // Compute the fp-to-sp delta, and correct one word for bailout id.
-  __ Add(fp_to_sp, masm()->StackPointer(),
-         kSavedRegistersAreaSize + (1 * kPointerSize));
-  __ Sub(fp_to_sp, fp, fp_to_sp);
-
-  // Allocate a new deoptimizer object.
-  __ Ldr(x0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-  __ Mov(x1, type());
-  // Following arguments are already loaded:
-  //  - x2: bailout id
-  //  - x3: code object address
-  //  - x4: fp-to-sp delta
-  __ Mov(x5, Operand(ExternalReference::isolate_address(isolate())));
-
-  {
-    // Call Deoptimizer::New().
-    AllowExternalCallThatCantCauseGC scope(masm());
-    __ CallCFunction(ExternalReference::new_deoptimizer_function(isolate()), 6);
-  }
-
-  // Preserve "deoptimizer" object in register x0.
-  Register deoptimizer = x0;
-
-  // Get the input frame descriptor pointer.
-  __ Ldr(x1, MemOperand(deoptimizer, Deoptimizer::input_offset()));
-
-  // Copy core registers into the input frame.
-  CPURegList copy_to_input = saved_registers;
-  for (int i = 0; i < saved_registers.Count(); i++) {
-    // TODO(all): Look for opportunities to optimize this by using ldp/stp.
-    __ Peek(x2, i * kPointerSize);
-    CPURegister current_reg = copy_to_input.PopLowestIndex();
-    int offset = (current_reg.code() * kPointerSize) +
-        FrameDescription::registers_offset();
-    __ Str(x2, MemOperand(x1, offset));
-  }
-
-  // Copy FP registers to the input frame.
-  for (int i = 0; i < saved_fp_registers.Count(); i++) {
-    // TODO(all): Look for opportunities to optimize this by using ldp/stp.
-    int dst_offset = FrameDescription::double_registers_offset() +
-        (i * kDoubleSize);
-    int src_offset = kFPRegistersOffset + (i * kDoubleSize);
-    __ Peek(x2, src_offset);
-    __ Str(x2, MemOperand(x1, dst_offset));
-  }
-
-  // Remove the bailout id and the saved registers from the stack.
-  __ Drop(1 + (kSavedRegistersAreaSize / kXRegSizeInBytes));
-
-  // Compute a pointer to the unwinding limit in register x2; that is
-  // the first stack slot not part of the input frame.
-  Register unwind_limit = x2;
-  __ Ldr(unwind_limit, MemOperand(x1, FrameDescription::frame_size_offset()));
-  __ Add(unwind_limit, unwind_limit, __ StackPointer());
-
-  // Unwind the stack down to - but not including - the unwinding
-  // limit and copy the contents of the activation frame to the input
-  // frame description.
-  __ Add(x3, x1, FrameDescription::frame_content_offset());
-  Label pop_loop;
-  Label pop_loop_header;
-  __ B(&pop_loop_header);
-  __ Bind(&pop_loop);
-  __ Pop(x4);
-  __ Str(x4, MemOperand(x3, kPointerSize, PostIndex));
-  __ Bind(&pop_loop_header);
-  __ Cmp(unwind_limit, __ StackPointer());
-  __ B(ne, &pop_loop);
-
-  // Compute the output frame in the deoptimizer.
-  __ Push(x0);  // Preserve deoptimizer object across call.
-
-  {
-    // Call Deoptimizer::ComputeOutputFrames().
-    AllowExternalCallThatCantCauseGC scope(masm());
-    __ CallCFunction(
-        ExternalReference::compute_output_frames_function(isolate()), 1);
-  }
-  __ Pop(x4);  // Restore deoptimizer object (class Deoptimizer).
-
-  // Replace the current (input) frame with the output frames.
-  Label outer_push_loop, inner_push_loop,
-      outer_loop_header, inner_loop_header;
-  __ Ldrsw(x1, MemOperand(x4, Deoptimizer::output_count_offset()));
-  __ Ldr(x0, MemOperand(x4, Deoptimizer::output_offset()));
-  __ Add(x1, x0, Operand(x1, LSL, kPointerSizeLog2));
-  __ B(&outer_loop_header);
-
-  __ Bind(&outer_push_loop);
-  Register current_frame = x2;
-  __ Ldr(current_frame, MemOperand(x0, 0));
-  __ Ldr(x3, MemOperand(current_frame, FrameDescription::frame_size_offset()));
-  __ B(&inner_loop_header);
-
-  __ Bind(&inner_push_loop);
-  __ Sub(x3, x3, kPointerSize);
-  __ Add(x6, current_frame, x3);
-  __ Ldr(x7, MemOperand(x6, FrameDescription::frame_content_offset()));
-  __ Push(x7);
-  __ Bind(&inner_loop_header);
-  __ Cbnz(x3, &inner_push_loop);
-
-  __ Add(x0, x0, kPointerSize);
-  __ Bind(&outer_loop_header);
-  __ Cmp(x0, x1);
-  __ B(lt, &outer_push_loop);
-
-  __ Ldr(x1, MemOperand(x4, Deoptimizer::input_offset()));
-  ASSERT(!saved_fp_registers.IncludesAliasOf(crankshaft_fp_scratch) &&
-         !saved_fp_registers.IncludesAliasOf(fp_zero) &&
-         !saved_fp_registers.IncludesAliasOf(fp_scratch));
-  int src_offset = FrameDescription::double_registers_offset();
-  while (!saved_fp_registers.IsEmpty()) {
-    const CPURegister reg = saved_fp_registers.PopLowestIndex();
-    __ Ldr(reg, MemOperand(x1, src_offset));
-    src_offset += kDoubleSize;
-  }
-
-  // Push state from the last output frame.
-  __ Ldr(x6, MemOperand(current_frame, FrameDescription::state_offset()));
-  __ Push(x6);
-
-  // TODO(all): ARM copies a lot (if not all) of the last output frame onto the
-  // stack, then pops it all into registers. Here, we try to load it directly
-  // into the relevant registers. Is this correct? If so, we should improve the
-  // ARM code.
-
-  // TODO(all): This code needs to be revisited, We probably don't need to
-  // restore all the registers as fullcodegen does not keep live values in
-  // registers (note that at least fp must be restored though).
-
-  // Restore registers from the last output frame.
-  // Note that lr is not in the list of saved_registers and will be restored
-  // later. We can use it to hold the address of last output frame while
-  // reloading the other registers.
-  ASSERT(!saved_registers.IncludesAliasOf(lr));
-  Register last_output_frame = lr;
-  __ Mov(last_output_frame, current_frame);
-
-  // We don't need to restore x7 as it will be clobbered later to hold the
-  // continuation address.
-  Register continuation = x7;
-  saved_registers.Remove(continuation);
-
-  while (!saved_registers.IsEmpty()) {
-    // TODO(all): Look for opportunities to optimize this by using ldp.
-    CPURegister current_reg = saved_registers.PopLowestIndex();
-    int offset = (current_reg.code() * kPointerSize) +
-        FrameDescription::registers_offset();
-    __ Ldr(current_reg, MemOperand(last_output_frame, offset));
-  }
-
-  __ Ldr(continuation, MemOperand(last_output_frame,
-                                  FrameDescription::continuation_offset()));
-  __ Ldr(lr, MemOperand(last_output_frame, FrameDescription::pc_offset()));
-  __ InitializeRootRegister();
-  __ Br(continuation);
-}
-
-
-// Size of an entry of the second level deopt table.
-// This is the code size generated by GeneratePrologue for one entry.
-const int Deoptimizer::table_entry_size_ = 2 * kInstructionSize;
-
-
-void Deoptimizer::TableEntryGenerator::GeneratePrologue() {
-  // Create a sequence of deoptimization entries.
-  // Note that registers are still live when jumping to an entry.
-  Label done;
-  {
-    InstructionAccurateScope scope(masm());
-
-    // The number of entry will never exceed kMaxNumberOfEntries.
-    // As long as kMaxNumberOfEntries is a valid 16 bits immediate you can use
-    // a movz instruction to load the entry id.
-    ASSERT(is_uint16(Deoptimizer::kMaxNumberOfEntries));
-
-    for (int i = 0; i < count(); i++) {
-      int start = masm()->pc_offset();
-      USE(start);
-      __ movz(masm()->Tmp0(), i);
-      __ b(&done);
-      ASSERT(masm()->pc_offset() - start == table_entry_size_);
-    }
-  }
-  __ Bind(&done);
-  // TODO(all): We need to add some kind of assertion to verify that Tmp0()
-  // is not clobbered by Push.
-  __ Push(masm()->Tmp0());
-}
-
-
-void FrameDescription::SetCallerPc(unsigned offset, intptr_t value) {
-  SetFrameSlot(offset, value);
-}
-
-
-void FrameDescription::SetCallerFp(unsigned offset, intptr_t value) {
-  SetFrameSlot(offset, value);
-}
-
-
-#undef __
-
-} }  // namespace v8::internal