Rename A64 port to ARM64 port

src/a64/debug-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"
-
-#if V8_TARGET_ARCH_A64
-
-#include "codegen.h"
-#include "debug.h"
-
-namespace v8 {
-namespace internal {
-
-
-#define __ ACCESS_MASM(masm)
-
-
-#ifdef ENABLE_DEBUGGER_SUPPORT
-bool BreakLocationIterator::IsDebugBreakAtReturn() {
-  return Debug::IsDebugBreakAtReturn(rinfo());
-}
-
-
-void BreakLocationIterator::SetDebugBreakAtReturn() {
-  // Patch the code emitted by FullCodeGenerator::EmitReturnSequence, changing
-  // the return from JS function sequence from
-  //   mov sp, fp
-  //   ldp fp, lr, [sp] #16
-  //   lrd ip0, [pc, #(3 * kInstructionSize)]
-  //   add sp, sp, ip0
-  //   ret
-  //   <number of paramters ...
-  //    ... plus one (64 bits)>
-  // to a call to the debug break return code.
-  //   ldr ip0, [pc, #(3 * kInstructionSize)]
-  //   blr ip0
-  //   hlt kHltBadCode    @ code should not return, catch if it does.
-  //   <debug break return code ...
-  //    ... entry point address (64 bits)>
-
-  // The patching code must not overflow the space occupied by the return
-  // sequence.
-  STATIC_ASSERT(Assembler::kJSRetSequenceInstructions >= 5);
-  PatchingAssembler patcher(reinterpret_cast<Instruction*>(rinfo()->pc()), 5);
-  byte* entry =
-      debug_info_->GetIsolate()->debug()->debug_break_return()->entry();
-
-  // The first instruction of a patched return sequence must be a load literal
-  // loading the address of the debug break return code.
-  patcher.LoadLiteral(ip0, 3 * kInstructionSize);
-  // TODO(all): check the following is correct.
-  // The debug break return code will push a frame and call statically compiled
-  // code. By using blr, even though control will not return after the branch,
-  // this call site will be registered in the frame (lr being saved as the pc
-  // of the next instruction to execute for this frame). The debugger can now
-  // iterate on the frames to find call to debug break return code.
-  patcher.blr(ip0);
-  patcher.hlt(kHltBadCode);
-  patcher.dc64(reinterpret_cast<int64_t>(entry));
-}
-
-
-void BreakLocationIterator::ClearDebugBreakAtReturn() {
-  // Reset the code emitted by EmitReturnSequence to its original state.
-  rinfo()->PatchCode(original_rinfo()->pc(),
-                     Assembler::kJSRetSequenceInstructions);
-}
-
-
-bool Debug::IsDebugBreakAtReturn(RelocInfo* rinfo) {
-  ASSERT(RelocInfo::IsJSReturn(rinfo->rmode()));
-  return rinfo->IsPatchedReturnSequence();
-}
-
-
-bool BreakLocationIterator::IsDebugBreakAtSlot() {
-  ASSERT(IsDebugBreakSlot());
-  // Check whether the debug break slot instructions have been patched.
-  return rinfo()->IsPatchedDebugBreakSlotSequence();
-}
-
-
-void BreakLocationIterator::SetDebugBreakAtSlot() {
-  // Patch the code emitted by Debug::GenerateSlots, changing the debug break
-  // slot code from
-  //   mov x0, x0    @ nop DEBUG_BREAK_NOP
-  //   mov x0, x0    @ nop DEBUG_BREAK_NOP
-  //   mov x0, x0    @ nop DEBUG_BREAK_NOP
-  //   mov x0, x0    @ nop DEBUG_BREAK_NOP
-  // to a call to the debug slot code.
-  //   ldr ip0, [pc, #(2 * kInstructionSize)]
-  //   blr ip0
-  //   <debug break slot code ...
-  //    ... entry point address (64 bits)>
-
-  // TODO(all): consider adding a hlt instruction after the blr as we don't
-  // expect control to return here. This implies increasing
-  // kDebugBreakSlotInstructions to 5 instructions.
-
-  // The patching code must not overflow the space occupied by the return
-  // sequence.
-  STATIC_ASSERT(Assembler::kDebugBreakSlotInstructions >= 4);
-  PatchingAssembler patcher(reinterpret_cast<Instruction*>(rinfo()->pc()), 4);
-  byte* entry =
-      debug_info_->GetIsolate()->debug()->debug_break_slot()->entry();
-
-  // The first instruction of a patched debug break slot must be a load literal
-  // loading the address of the debug break slot code.
-  patcher.LoadLiteral(ip0, 2 * kInstructionSize);
-  // TODO(all): check the following is correct.
-  // The debug break slot code will push a frame and call statically compiled
-  // code. By using blr, event hough control will not return after the branch,
-  // this call site will be registered in the frame (lr being saved as the pc
-  // of the next instruction to execute for this frame). The debugger can now
-  // iterate on the frames to find call to debug break slot code.
-  patcher.blr(ip0);
-  patcher.dc64(reinterpret_cast<int64_t>(entry));
-}
-
-
-void BreakLocationIterator::ClearDebugBreakAtSlot() {
-  ASSERT(IsDebugBreakSlot());
-  rinfo()->PatchCode(original_rinfo()->pc(),
-                     Assembler::kDebugBreakSlotInstructions);
-}
-
-const bool Debug::FramePaddingLayout::kIsSupported = false;
-
-static void Generate_DebugBreakCallHelper(MacroAssembler* masm,
-                                          RegList object_regs,
-                                          RegList non_object_regs,
-                                          Register scratch) {
-  {
-    FrameScope scope(masm, StackFrame::INTERNAL);
-
-    // Any live values (object_regs and non_object_regs) in caller-saved
-    // registers (or lr) need to be stored on the stack so that their values are
-    // safely preserved for a call into C code.
-    //
-    // Also:
-    //  * object_regs may be modified during the C code by the garbage
-    //    collector. Every object register must be a valid tagged pointer or
-    //    SMI.
-    //
-    //  * non_object_regs will be converted to SMIs so that the garbage
-    //    collector doesn't try to interpret them as pointers.
-    //
-    // TODO(jbramley): Why can't this handle callee-saved registers?
-    ASSERT((~kCallerSaved.list() & object_regs) == 0);
-    ASSERT((~kCallerSaved.list() & non_object_regs) == 0);
-    ASSERT((object_regs & non_object_regs) == 0);
-    ASSERT((scratch.Bit() & object_regs) == 0);
-    ASSERT((scratch.Bit() & non_object_regs) == 0);
-    ASSERT((masm->TmpList()->list() & (object_regs | non_object_regs)) == 0);
-    STATIC_ASSERT(kSmiValueSize == 32);
-
-    CPURegList non_object_list =
-        CPURegList(CPURegister::kRegister, kXRegSizeInBits, non_object_regs);
-    while (!non_object_list.IsEmpty()) {
-      // Store each non-object register as two SMIs.
-      Register reg = Register(non_object_list.PopLowestIndex());
-      __ Push(reg);
-      __ Poke(wzr, 0);
-      __ Push(reg.W(), wzr);
-      // Stack:
-      //  jssp[12]: reg[63:32]
-      //  jssp[8]: 0x00000000 (SMI tag & padding)
-      //  jssp[4]: reg[31:0]
-      //  jssp[0]: 0x00000000 (SMI tag & padding)
-      STATIC_ASSERT((kSmiTag == 0) && (kSmiShift == 32));
-    }
-
-    if (object_regs != 0) {
-      __ PushXRegList(object_regs);
-    }
-
-#ifdef DEBUG
-    __ RecordComment("// Calling from debug break to runtime - come in - over");
-#endif
-    __ Mov(x0, 0);  // No arguments.
-    __ Mov(x1, ExternalReference::debug_break(masm->isolate()));
-
-    CEntryStub stub(1);
-    __ CallStub(&stub);
-
-    // Restore the register values from the expression stack.
-    if (object_regs != 0) {
-      __ PopXRegList(object_regs);
-    }
-
-    non_object_list =
-        CPURegList(CPURegister::kRegister, kXRegSizeInBits, non_object_regs);
-    while (!non_object_list.IsEmpty()) {
-      // Load each non-object register from two SMIs.
-      // Stack:
-      //  jssp[12]: reg[63:32]
-      //  jssp[8]: 0x00000000 (SMI tag & padding)
-      //  jssp[4]: reg[31:0]
-      //  jssp[0]: 0x00000000 (SMI tag & padding)
-      Register reg = Register(non_object_list.PopHighestIndex());
-      __ Pop(scratch, reg);
-      __ Bfxil(reg, scratch, 32, 32);
-    }
-
-    // Leave the internal frame.
-  }
-
-  // Now that the break point has been handled, resume normal execution by
-  // jumping to the target address intended by the caller and that was
-  // overwritten by the address of DebugBreakXXX.
-  ExternalReference after_break_target(Debug_Address::AfterBreakTarget(),
-                                       masm->isolate());
-  __ Mov(scratch, after_break_target);
-  __ Ldr(scratch, MemOperand(scratch));
-  __ Br(scratch);
-}
-
-
-void Debug::GenerateLoadICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC load (from ic-arm.cc).
-  // ----------- S t a t e -------------
-  //  -- x2    : name
-  //  -- lr    : return address
-  //  -- x0    : receiver
-  //  -- [sp]  : receiver
-  // -----------------------------------
-  // Registers x0 and x2 contain objects that need to be pushed on the
-  // expression stack of the fake JS frame.
-  Generate_DebugBreakCallHelper(masm, x0.Bit() | x2.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateStoreICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC store (from ic-arm.cc).
-  // ----------- S t a t e -------------
-  //  -- x0    : value
-  //  -- x1    : receiver
-  //  -- x2    : name
-  //  -- lr    : return address
-  // -----------------------------------
-  // Registers x0, x1, and x2 contain objects that need to be pushed on the
-  // expression stack of the fake JS frame.
-  Generate_DebugBreakCallHelper(masm, x0.Bit() | x1.Bit() | x2.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateKeyedLoadICDebugBreak(MacroAssembler* masm) {
-  // ---------- S t a t e --------------
-  //  -- lr     : return address
-  //  -- x0     : key
-  //  -- x1     : receiver
-  Generate_DebugBreakCallHelper(masm, x0.Bit() | x1.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateKeyedStoreICDebugBreak(MacroAssembler* masm) {
-  // ---------- S t a t e --------------
-  //  -- x0     : value
-  //  -- x1     : key
-  //  -- x2     : receiver
-  //  -- lr     : return address
-  Generate_DebugBreakCallHelper(masm, x0.Bit() | x1.Bit() | x2.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateCompareNilICDebugBreak(MacroAssembler* masm) {
-  // Register state for CompareNil IC
-  // ----------- S t a t e -------------
-  //  -- r0    : value
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, x0.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateCallICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC call (from ic-arm.cc)
-  // ----------- S t a t e -------------
-  //  -- x2     : name
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, x2.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateReturnDebugBreak(MacroAssembler* masm) {
-  // In places other than IC call sites it is expected that r0 is TOS which
-  // is an object - this is not generally the case so this should be used with
-  // care.
-  Generate_DebugBreakCallHelper(masm, x0.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateCallFunctionStubDebugBreak(MacroAssembler* masm) {
-  // Register state for CallFunctionStub (from code-stubs-a64.cc).
-  // ----------- S t a t e -------------
-  //  -- x1 : function
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, x1.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateCallFunctionStubRecordDebugBreak(MacroAssembler* masm) {
-  // Register state for CallFunctionStub (from code-stubs-a64.cc).
-  // ----------- S t a t e -------------
-  //  -- x1 : function
-  //  -- x2 : feedback array
-  //  -- x3 : slot in feedback array
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, x1.Bit() | x2.Bit() | x3.Bit(), 0, x10);
-}
-
-
-void Debug::GenerateCallConstructStubDebugBreak(MacroAssembler* masm) {
-  // Calling convention for CallConstructStub (from code-stubs-a64.cc).
-  // ----------- S t a t e -------------
-  //  -- x0 : number of arguments (not smi)
-  //  -- x1 : constructor function
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, x1.Bit(), x0.Bit(), x10);
-}
-
-
-void Debug::GenerateCallConstructStubRecordDebugBreak(MacroAssembler* masm) {
-  // Calling convention for CallConstructStub (from code-stubs-a64.cc).
-  // ----------- S t a t e -------------
-  //  -- x0 : number of arguments (not smi)
-  //  -- x1 : constructor function
-  //  -- x2     : feedback array
-  //  -- x3     : feedback slot (smi)
-  // -----------------------------------
-  Generate_DebugBreakCallHelper(
-      masm, x1.Bit() | x2.Bit() | x3.Bit(), x0.Bit(), x10);
-}
-
-
-void Debug::GenerateSlot(MacroAssembler* masm) {
-  // Generate enough nop's to make space for a call instruction. Avoid emitting
-  // the constant pool in the debug break slot code.
-  InstructionAccurateScope scope(masm, Assembler::kDebugBreakSlotInstructions);
-
-  __ RecordDebugBreakSlot();
-  for (int i = 0; i < Assembler::kDebugBreakSlotInstructions; i++) {
-    __ nop(Assembler::DEBUG_BREAK_NOP);
-  }
-}
-
-
-void Debug::GenerateSlotDebugBreak(MacroAssembler* masm) {
-  // In the places where a debug break slot is inserted no registers can contain
-  // object pointers.
-  Generate_DebugBreakCallHelper(masm, 0, 0, x10);
-}
-
-
-void Debug::GeneratePlainReturnLiveEdit(MacroAssembler* masm) {
-  masm->Abort(kLiveEditFrameDroppingIsNotSupportedOnA64);
-}
-
-
-void Debug::GenerateFrameDropperLiveEdit(MacroAssembler* masm) {
-  masm->Abort(kLiveEditFrameDroppingIsNotSupportedOnA64);
-}
-
-const bool Debug::kFrameDropperSupported = false;
-
-#endif  // ENABLE_DEBUGGER_SUPPORT
-
-} }  // namespace v8::internal
-
-#endif  // V8_TARGET_ARCH_A64