CSE2410 Fall 2014 Bounce

// Copyright 2006-2008 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-inl.h"

#include "debug.h"

namespace v8 { namespace internal {

// Currently debug break is not supported in frame exit code on ARM.

bool BreakLocationIterator::IsDebugBreakAtReturn() {

  return false;

}

// Currently debug break is not supported in frame exit code on ARM.

void BreakLocationIterator::SetDebugBreakAtReturn() {

  UNIMPLEMENTED();

}

// Currently debug break is not supported in frame exit code on ARM.

void BreakLocationIterator::ClearDebugBreakAtReturn() {

  UNIMPLEMENTED();

}

bool Debug::IsDebugBreakAtReturn(RelocInfo* rinfo) {

  ASSERT(RelocInfo::IsJSReturn(rinfo->rmode()));

  // Currently debug break is not supported in frame exit code on ARM.

  return false;

}

#define __ masm->

static void Generate_DebugBreakCallHelper(MacroAssembler* masm,

                                          RegList pointer_regs) {

  // Save the content of all general purpose registers in memory. This copy in

  // memory is later pushed onto the JS expression stack for the fake JS frame

  // generated and also to the C frame generated on top of that. In the JS

  // frame ONLY the registers containing pointers will be pushed on the

  // expression stack. This causes the GC to update these  pointers so that

  // they will have the correct value when returning from the debugger.

  __ SaveRegistersToMemory(kJSCallerSaved);

  __ EnterInternalFrame();

  // Store the registers containing object pointers on the expression stack to

  // make sure that these are correctly updated during GC.

  // Use sp as base to push.

  __ CopyRegistersFromMemoryToStack(sp, pointer_regs);

#ifdef DEBUG

  __ RecordComment("// Calling from debug break to runtime - come in - over");

#endif

  __ mov(r0, Operand(0));  // no arguments

  __ mov(r1, Operand(ExternalReference::debug_break()));

  CEntryDebugBreakStub ceb;

  __ CallStub(&ceb);

  // Restore the register values containing object pointers from the expression

  // stack in the reverse order as they where pushed.

  // Use sp as base to pop.

  __ CopyRegistersFromStackToMemory(sp, r3, pointer_regs);

  __ LeaveInternalFrame();

  // Inlined ExitJSFrame ends here.

  // Finally restore all registers.

  __ RestoreRegistersFromMemory(kJSCallerSaved);

  // 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.

  __ mov(ip, Operand(ExternalReference(Debug_Address::AfterBreakTarget())));

  __ ldr(ip, MemOperand(ip));

  __ Jump(ip);

}

void Debug::GenerateLoadICDebugBreak(MacroAssembler* masm) {

  // Calling convention for IC load (from ic-arm.cc).

  // ----------- S t a t e -------------

  //  -- r0    : receiver

  //  -- r2    : name

  //  -- lr    : return address

  //  -- [sp]  : receiver

  // -----------------------------------

  // Registers r0 and r2 contain objects that needs to be pushed on the

  // expression stack of the fake JS frame.

  Generate_DebugBreakCallHelper(masm, r0.bit() | r2.bit());

}

void Debug::GenerateStoreICDebugBreak(MacroAssembler* masm) {

  // Calling convention for IC store (from ic-arm.cc).

  // ----------- S t a t e -------------

  //  -- r0    : receiver

  //  -- r2    : name

  //  -- lr    : return address

  //  -- [sp]  : receiver

  // -----------------------------------

  // Registers r0 and r2 contain objects that needs to be pushed on the

  // expression stack of the fake JS frame.

  Generate_DebugBreakCallHelper(masm, r0.bit() | r2.bit());

}

void Debug::GenerateKeyedLoadICDebugBreak(MacroAssembler* masm) {

  // Keyed load IC not implemented on ARM.

}

void Debug::GenerateKeyedStoreICDebugBreak(MacroAssembler* masm) {

  // Keyed store IC not implemented on ARM.

}

void Debug::GenerateCallICDebugBreak(MacroAssembler* masm) {

  // Calling convention for IC call (from ic-arm.cc)

  // ----------- S t a t e -------------

  //  -- r0: number of arguments

  //  -- r1: receiver

  //  -- lr: return address

  // -----------------------------------

  // Register r1 contains an object that needs to be pushed on the expression

  // stack of the fake JS frame. r0 is the actual number of arguments not

  // encoded as a smi, therefore it cannot be on the expression stack of the

  // fake JS frame as it can easily be an invalid pointer (e.g. 1). r0 will be

  // pushed on the stack of the C frame and restored from there.

  Generate_DebugBreakCallHelper(masm, r1.bit());

}

void Debug::GenerateConstructCallDebugBreak(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, r0.bit());

}

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, r0.bit());

}

void Debug::GenerateReturnDebugBreakEntry(MacroAssembler* masm) {

  // Generate nothing as this handling of debug break return is not done this

  // way on ARM  - yet.

}

void Debug::GenerateStubNoRegistersDebugBreak(MacroAssembler* masm) {

  // Generate nothing as CodeStub CallFunction is not used on ARM.

}

#undef __

} }  // namespace v8::internal