Contribution of PowerPC port.

src/ppc/debug-ppc.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
+//
+// Copyright IBM Corp. 2012, 2013. All rights reserved.
+//
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
-#if V8_TARGET_ARCH_ARM
+#if V8_TARGET_ARCH_PPC
 
 #include "src/codegen.h"
 #include "src/debug.h"
 
 namespace v8 {
 namespace internal {
 
 bool BreakLocationIterator::IsDebugBreakAtReturn() {
   return Debug::IsDebugBreakAtReturn(rinfo());
 }
 
 
 void BreakLocationIterator::SetDebugBreakAtReturn() {
   // Patch the code changing the return from JS function sequence from
-  //   mov sp, fp
-  //   ldmia sp!, {fp, lr}
-  //   add sp, sp, #4
-  //   bx lr
+  //
+  //   LeaveFrame
+  //   addi sp, sp, <delta>
+  //   blr
+  //
   // to a call to the debug break return code.
-  //   ldr ip, [pc, #0]
-  //   blx ip
-  //   <debug break return code entry point address>
-  //   bkpt 0
+  // this uses a FIXED_SEQUENCE to load an address constant
+  //
+  //   mov r0, <address>
+  //   mtlr r0
+  //   blrl
+  //   bkpt
+  //
   CodePatcher patcher(rinfo()->pc(), Assembler::kJSReturnSequenceInstructions);
-  patcher.masm()->ldr(v8::internal::ip, MemOperand(v8::internal::pc, 0));
-  patcher.masm()->blx(v8::internal::ip);
-  patcher.Emit(
-      debug_info_->GetIsolate()->builtins()->Return_DebugBreak()->entry());
+  Assembler::BlockTrampolinePoolScope block_trampoline_pool(patcher.masm());
+  patcher.masm()->mov(
+      v8::internal::r0,
+      Operand(reinterpret_cast<intptr_t>(debug_info_->GetIsolate()
+                                             ->builtins()
+                                             ->Return_DebugBreak()
+                                             ->entry())));
+  patcher.masm()->mtlr(v8::internal::r0);
+  patcher.masm()->bclr(BA, SetLK);
   patcher.masm()->bkpt(0);
 }
 
 
 // Restore the JS frame exit code.
 void BreakLocationIterator::ClearDebugBreakAtReturn() {
   rinfo()->PatchCode(original_rinfo()->pc(),
                      Assembler::kJSReturnSequenceInstructions);
 }
 
 
 // A debug break in the frame exit code is identified by the JS frame exit code
 // having been patched with a call instruction.
 bool Debug::IsDebugBreakAtReturn(RelocInfo* rinfo) {
   DCHECK(RelocInfo::IsJSReturn(rinfo->rmode()));
   return rinfo->IsPatchedReturnSequence();
 }
 
 
 bool BreakLocationIterator::IsDebugBreakAtSlot() {
   DCHECK(IsDebugBreakSlot());
   // Check whether the debug break slot instructions have been patched.
   return rinfo()->IsPatchedDebugBreakSlotSequence();
 }
 
 
 void BreakLocationIterator::SetDebugBreakAtSlot() {
   DCHECK(IsDebugBreakSlot());
   // Patch the code changing the debug break slot code from
-  //   mov r2, r2
-  //   mov r2, r2
-  //   mov r2, r2
-  // to a call to the debug break slot code.
-  //   ldr ip, [pc, #0]
-  //   blx ip
-  //   <debug break slot code entry point address>
+  //
+  //   ori r3, r3, 0
+  //   ori r3, r3, 0
+  //   ori r3, r3, 0
+  //   ori r3, r3, 0
+  //   ori r3, r3, 0
+  //
+  // to a call to the debug break code, using a FIXED_SEQUENCE.
+  //
+  //   mov r0, <address>
+  //   mtlr r0
+  //   blrl
+  //
   CodePatcher patcher(rinfo()->pc(), Assembler::kDebugBreakSlotInstructions);
-  patcher.masm()->ldr(v8::internal::ip, MemOperand(v8::internal::pc, 0));
-  patcher.masm()->blx(v8::internal::ip);
-  patcher.Emit(
-      debug_info_->GetIsolate()->builtins()->Slot_DebugBreak()->entry());
+  Assembler::BlockTrampolinePoolScope block_trampoline_pool(patcher.masm());
+  patcher.masm()->mov(
+      v8::internal::r0,
+      Operand(reinterpret_cast<intptr_t>(
+          debug_info_->GetIsolate()->builtins()->Slot_DebugBreak()->entry())));
+  patcher.masm()->mtlr(v8::internal::r0);
+  patcher.masm()->bclr(BA, SetLK);
 }
 
 
 void BreakLocationIterator::ClearDebugBreakAtSlot() {
   DCHECK(IsDebugBreakSlot());
   rinfo()->PatchCode(original_rinfo()->pc(),
                      Assembler::kDebugBreakSlotInstructions);
 }
 
 
 #define __ ACCESS_MASM(masm)
 
 
 static void Generate_DebugBreakCallHelper(MacroAssembler* masm,
                                           RegList object_regs,
                                           RegList non_object_regs) {
   {
     FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
 
     // Load padding words on stack.
-    __ mov(ip, Operand(Smi::FromInt(LiveEdit::kFramePaddingValue)));
+    __ LoadSmiLiteral(ip, Smi::FromInt(LiveEdit::kFramePaddingValue));
     for (int i = 0; i < LiveEdit::kFramePaddingInitialSize; i++) {
       __ push(ip);
     }
-    __ mov(ip, Operand(Smi::FromInt(LiveEdit::kFramePaddingInitialSize)));
+    __ LoadSmiLiteral(ip, Smi::FromInt(LiveEdit::kFramePaddingInitialSize));
     __ push(ip);
 
     // Store the registers containing live values on the expression stack to
     // make sure that these are correctly updated during GC. Non object values
     // are stored as a smi causing it to be untouched by GC.
     DCHECK((object_regs & ~kJSCallerSaved) == 0);
     DCHECK((non_object_regs & ~kJSCallerSaved) == 0);
     DCHECK((object_regs & non_object_regs) == 0);
     if ((object_regs | non_object_regs) != 0) {
       for (int i = 0; i < kNumJSCallerSaved; i++) {
         int r = JSCallerSavedCode(i);
-        Register reg = { r };
+        Register reg = {r};
         if ((non_object_regs & (1 << r)) != 0) {
           if (FLAG_debug_code) {
-            __ tst(reg, Operand(0xc0000000));
-            __ Assert(eq, kUnableToEncodeValueAsSmi);
+            __ TestUnsignedSmiCandidate(reg, r0);
+            __ Assert(eq, kUnableToEncodeValueAsSmi, cr0);
           }
           __ SmiTag(reg);
         }
       }
-      __ stm(db_w, sp, object_regs | non_object_regs);
+      __ MultiPush(object_regs | non_object_regs);
     }
 
 #ifdef DEBUG
     __ RecordComment("// Calling from debug break to runtime - come in - over");
 #endif
-    __ mov(r0, Operand::Zero());  // no arguments
-    __ mov(r1, Operand(ExternalReference::debug_break(masm->isolate())));
+    __ mov(r3, Operand::Zero());  // no arguments
+    __ mov(r4, Operand(ExternalReference::debug_break(masm->isolate())));
 
     CEntryStub ceb(masm->isolate(), 1);
     __ CallStub(&ceb);
 
     // Restore the register values from the expression stack.
     if ((object_regs | non_object_regs) != 0) {
-      __ ldm(ia_w, sp, object_regs | non_object_regs);
+      __ MultiPop(object_regs | non_object_regs);
       for (int i = 0; i < kNumJSCallerSaved; i++) {
         int r = JSCallerSavedCode(i);
-        Register reg = { r };
+        Register reg = {r};
         if ((non_object_regs & (1 << r)) != 0) {
           __ SmiUntag(reg);
         }
         if (FLAG_debug_code &&
-            (((object_regs |non_object_regs) & (1 << r)) == 0)) {
+            (((object_regs | non_object_regs) & (1 << r)) == 0)) {
           __ mov(reg, Operand(kDebugZapValue));
         }
       }
     }
 
     // Don't bother removing padding bytes pushed on the stack
     // as the frame is going to be restored right away.
 
     // 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 =
       ExternalReference::debug_after_break_target_address(masm->isolate());
   __ mov(ip, Operand(after_break_target));
-  __ ldr(ip, MemOperand(ip));
+  __ LoadP(ip, MemOperand(ip));
   __ Jump(ip);
 }
 
 
 void DebugCodegen::GenerateCallICStubDebugBreak(MacroAssembler* masm) {
   // Register state for CallICStub
   // ----------- S t a t e -------------
-  //  -- r1 : function
-  //  -- r3 : slot in feedback array (smi)
+  //  -- r4 : function
+  //  -- r6 : slot in feedback array (smi)
   // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, r1.bit() | r3.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, r4.bit() | r6.bit(), 0);
 }
 
 
 void DebugCodegen::GenerateLoadICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC load (from ic-arm.cc).
+  // Calling convention for IC load (from ic-ppc.cc).
   Register receiver = LoadIC::ReceiverRegister();
   Register name = LoadIC::NameRegister();
   Generate_DebugBreakCallHelper(masm, receiver.bit() | name.bit(), 0);
 }
 
 
 void DebugCodegen::GenerateStoreICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC store (from ic-arm.cc).
+  // Calling convention for IC store (from ic-ppc.cc).
   Register receiver = StoreIC::ReceiverRegister();
   Register name = StoreIC::NameRegister();
   Register value = StoreIC::ValueRegister();
-  Generate_DebugBreakCallHelper(
-      masm, receiver.bit() | name.bit() | value.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, receiver.bit() | name.bit() | value.bit(),
+                                0);
 }
 
 
 void DebugCodegen::GenerateKeyedLoadICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for keyed IC load (from ic-arm.cc).
+  // Calling convention for keyed IC load (from ic-ppc.cc).
   GenerateLoadICDebugBreak(masm);
 }
 
 
 void DebugCodegen::GenerateKeyedStoreICDebugBreak(MacroAssembler* masm) {
-  // Calling convention for IC keyed store call (from ic-arm.cc).
+  // Calling convention for IC keyed store call (from ic-ppc.cc).
   Register receiver = KeyedStoreIC::ReceiverRegister();
   Register name = KeyedStoreIC::NameRegister();
   Register value = KeyedStoreIC::ValueRegister();
-  Generate_DebugBreakCallHelper(
-      masm, receiver.bit() | name.bit() | value.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, receiver.bit() | name.bit() | value.bit(),
+                                0);
 }
 
 
 void DebugCodegen::GenerateCompareNilICDebugBreak(MacroAssembler* masm) {
   // Register state for CompareNil IC
   // ----------- S t a t e -------------
-  //  -- r0    : value
+  //  -- r3    : value
   // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, r0.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, r3.bit(), 0);
 }
 
 
 void DebugCodegen::GenerateReturnDebugBreak(MacroAssembler* masm) {
-  // In places other than IC call sites it is expected that r0 is TOS which
+  // In places other than IC call sites it is expected that r3 is TOS which
   // is an object - this is not generally the case so this should be used with
   // care.
-  Generate_DebugBreakCallHelper(masm, r0.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, r3.bit(), 0);
 }
 
 
 void DebugCodegen::GenerateCallFunctionStubDebugBreak(MacroAssembler* masm) {
-  // Register state for CallFunctionStub (from code-stubs-arm.cc).
+  // Register state for CallFunctionStub (from code-stubs-ppc.cc).
   // ----------- S t a t e -------------
-  //  -- r1 : function
+  //  -- r4 : function
   // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, r1.bit(), 0);
+  Generate_DebugBreakCallHelper(masm, r4.bit(), 0);
 }
 
 
 void DebugCodegen::GenerateCallConstructStubDebugBreak(MacroAssembler* masm) {
-  // Calling convention for CallConstructStub (from code-stubs-arm.cc)
+  // Calling convention for CallConstructStub (from code-stubs-ppc.cc)
   // ----------- S t a t e -------------
-  //  -- r0     : number of arguments (not smi)
-  //  -- r1     : constructor function
+  //  -- r3     : number of arguments (not smi)
+  //  -- r4     : constructor function
   // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, r1.bit(), r0.bit());
+  Generate_DebugBreakCallHelper(masm, r4.bit(), r3.bit());
 }
 
 
 void DebugCodegen::GenerateCallConstructStubRecordDebugBreak(
     MacroAssembler* masm) {
-  // Calling convention for CallConstructStub (from code-stubs-arm.cc)
+  // Calling convention for CallConstructStub (from code-stubs-ppc.cc)
   // ----------- S t a t e -------------
-  //  -- r0     : number of arguments (not smi)
-  //  -- r1     : constructor function
-  //  -- r2     : feedback array
-  //  -- r3     : feedback slot (smi)
+  //  -- r3     : number of arguments (not smi)
+  //  -- r4     : constructor function
+  //  -- r5     : feedback array
+  //  -- r6     : feedback slot (smi)
   // -----------------------------------
-  Generate_DebugBreakCallHelper(masm, r1.bit() | r2.bit() | r3.bit(), r0.bit());
+  Generate_DebugBreakCallHelper(masm, r4.bit() | r5.bit() | r6.bit(), r3.bit());
 }
 
 
 void DebugCodegen::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.
-  Assembler::BlockConstPoolScope block_const_pool(masm);
+  // the trampoline pool in the debug break slot code.
+  Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm);
   Label check_codesize;
   __ bind(&check_codesize);
   __ RecordDebugBreakSlot();
   for (int i = 0; i < Assembler::kDebugBreakSlotInstructions; i++) {
     __ nop(MacroAssembler::DEBUG_BREAK_NOP);
   }
   DCHECK_EQ(Assembler::kDebugBreakSlotInstructions,
             masm->InstructionsGeneratedSince(&check_codesize));
 }
 
 
 void DebugCodegen::GenerateSlotDebugBreak(MacroAssembler* masm) {
   // In the places where a debug break slot is inserted no registers can contain
   // object pointers.
   Generate_DebugBreakCallHelper(masm, 0, 0);
 }
 
 
 void DebugCodegen::GeneratePlainReturnLiveEdit(MacroAssembler* masm) {
   __ Ret();
 }
 
 
 void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) {
   ExternalReference restarter_frame_function_slot =
       ExternalReference::debug_restarter_frame_function_pointer_address(
           masm->isolate());
   __ mov(ip, Operand(restarter_frame_function_slot));
-  __ mov(r1, Operand::Zero());
-  __ str(r1, MemOperand(ip, 0));
+  __ li(r4, Operand::Zero());
+  __ StoreP(r4, MemOperand(ip, 0));
 
   // Load the function pointer off of our current stack frame.
-  __ ldr(r1, MemOperand(fp,
-         StandardFrameConstants::kConstantPoolOffset - kPointerSize));
+  __ LoadP(r4, MemOperand(fp, StandardFrameConstants::kConstantPoolOffset -
+                                  kPointerSize));
 
   // Pop return address, frame and constant pool pointer (if
   // FLAG_enable_ool_constant_pool).
   __ LeaveFrame(StackFrame::INTERNAL);
 
-  { ConstantPoolUnavailableScope constant_pool_unavailable(masm);
-    // Load context from the function.
-    __ ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
+  // Load context from the function.
+  __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
 
-    // Get function code.
-    __ ldr(ip, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
-    __ ldr(ip, FieldMemOperand(ip, SharedFunctionInfo::kCodeOffset));
-    __ add(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
+  // Get function code.
+  __ LoadP(ip, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
+  __ LoadP(ip, FieldMemOperand(ip, SharedFunctionInfo::kCodeOffset));
+  __ addi(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
 
-    // Re-run JSFunction, r1 is function, cp is context.
-    __ Jump(ip);
-  }
+  // Re-run JSFunction, r4 is function, cp is context.
+  __ Jump(ip);
 }
 
 
 const bool LiveEdit::kFrameDropperSupported = true;
 
 #undef __
+}
+}  // namespace v8::internal
 
-} }  // namespace v8::internal
-
-#endif  // V8_TARGET_ARCH_ARM
+#endif  // V8_TARGET_ARCH_PPC