A64: Synchronize with r17104.

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index bd9524cbc52763c23c551c4fc620ad917fbdc779..a4d2e183420a04f57c27c068eb2f7ab1d0ad8f74 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -386,9 +386,9 @@ void LAccessArgumentsAt::PrintDataTo(StringStream* stream) {
 }
 
 
-int LPlatformChunk::GetNextSpillIndex(bool is_double) {
+int LPlatformChunk::GetNextSpillIndex(RegisterKind kind) {
   // Skip a slot if for a double-width slot.
-  if (is_double) {
+  if (kind == DOUBLE_REGISTERS) {
     spill_slot_count_++;
     spill_slot_count_ |= 1;
     num_double_slots_++;
@@ -397,11 +397,12 @@ int LPlatformChunk::GetNextSpillIndex(bool is_double) {
 }
 
 
-LOperand* LPlatformChunk::GetNextSpillSlot(bool is_double) {
-  int index = GetNextSpillIndex(is_double);
-  if (is_double) {
+LOperand* LPlatformChunk::GetNextSpillSlot(RegisterKind kind) {
+  int index = GetNextSpillIndex(kind);
+  if (kind == DOUBLE_REGISTERS) {
     return LDoubleStackSlot::Create(index, zone());
   } else {
+    ASSERT(kind == GENERAL_REGISTERS);
     return LStackSlot::Create(index, zone());
   }
 }
@@ -479,7 +480,7 @@ LPlatformChunk* LChunkBuilder::Build() {
 
   // Reserve the first spill slot for the state of dynamic alignment.
   if (info()->IsOptimizing()) {
-    int alignment_state_index = chunk_->GetNextSpillIndex(false);
+    int alignment_state_index = chunk_->GetNextSpillIndex(GENERAL_REGISTERS);
     ASSERT_EQ(alignment_state_index, 0);
     USE(alignment_state_index);
   }
@@ -488,7 +489,7 @@ LPlatformChunk* LChunkBuilder::Build() {
   // which will be subsumed into this frame.
   if (graph()->has_osr()) {
     for (int i = graph()->osr()->UnoptimizedFrameSlots(); i > 0; i--) {
-      chunk_->GetNextSpillIndex(false);
+      chunk_->GetNextSpillIndex(GENERAL_REGISTERS);
     }
   }
 
@@ -908,9 +909,31 @@ void LChunkBuilder::VisitInstruction(HInstruction* current) {
   HInstruction* old_current = current_instruction_;
   current_instruction_ = current;
   if (current->has_position()) position_ = current->position();
-  LInstruction* instr = current->CompileToLithium(this);
+
+  LInstruction* instr = NULL;
+  if (current->CanReplaceWithDummyUses()) {
+    HValue* first_operand = current->OperandCount() == 0
+        ? graph()->GetConstant1()
+        : current->OperandAt(0);
+    instr = DefineAsRegister(new(zone()) LDummyUse(UseAny(first_operand)));
+    for (int i = 1; i < current->OperandCount(); ++i) {
+      LInstruction* dummy =
+          new(zone()) LDummyUse(UseAny(current->OperandAt(i)));
+      dummy->set_hydrogen_value(current);
+      chunk_->AddInstruction(dummy, current_block_);
+    }
+  } else {
+    instr = current->CompileToLithium(this);
+  }
+
+  argument_count_ += current->argument_delta();
+  ASSERT(argument_count_ >= 0);
 
   if (instr != NULL) {
+    // Associate the hydrogen instruction first, since we may need it for
+    // the ClobbersRegisters() or ClobbersDoubleRegisters() calls below.
+    instr->set_hydrogen_value(current);
+
 #if DEBUG
     // Make sure that the lithium instruction has either no fixed register
     // constraints in temps or the result OR no uses that are only used at
@@ -957,7 +980,6 @@ void LChunkBuilder::VisitInstruction(HInstruction* current) {
       clobber->set_hydrogen_value(current);
       chunk_->AddInstruction(clobber, current_block_);
     }
-    instr->set_hydrogen_value(current);
     chunk_->AddInstruction(instr, current_block_);
   }
   current_instruction_ = old_current;
@@ -1054,21 +1076,15 @@ LInstruction* LChunkBuilder::DoGoto(HGoto* instr) {
 
 
 LInstruction* LChunkBuilder::DoBranch(HBranch* instr) {
-  HValue* value = instr->value();
-  if (value->EmitAtUses()) {
-    ASSERT(value->IsConstant());
-    ASSERT(!value->representation().IsDouble());
-    HBasicBlock* successor = HConstant::cast(value)->BooleanValue()
-        ? instr->FirstSuccessor()
-        : instr->SecondSuccessor();
-    return new(zone()) LGoto(successor);
-  }
+  LInstruction* goto_instr = CheckElideControlInstruction(instr);
+  if (goto_instr != NULL) return goto_instr;
 
   ToBooleanStub::Types expected = instr->expected_input_types();
 
   // Tagged values that are not known smis or booleans require a
   // deoptimization environment. If the instruction is generic no
   // environment is needed since all cases are handled.
+  HValue* value = instr->value();
   Representation rep = value->representation();
   HType type = value->type();
   if (!rep.IsTagged() || type.IsSmi() || type.IsBoolean()) {
@@ -1164,7 +1180,6 @@ LInstruction* LChunkBuilder::DoApplyArguments(HApplyArguments* instr) {
 
 
 LInstruction* LChunkBuilder::DoPushArgument(HPushArgument* instr) {
-  ++argument_count_;
   LOperand* argument = UseAny(instr->argument());
   return new(zone()) LPushArgument(argument);
 }
@@ -1231,7 +1246,6 @@ LInstruction* LChunkBuilder::DoGlobalReceiver(HGlobalReceiver* instr) {
 
 LInstruction* LChunkBuilder::DoCallConstantFunction(
     HCallConstantFunction* instr) {
-  argument_count_ -= instr->argument_count();
   return MarkAsCall(DefineFixed(new(zone()) LCallConstantFunction, eax), instr);
 }
 
@@ -1239,7 +1253,6 @@ LInstruction* LChunkBuilder::DoCallConstantFunction(
 LInstruction* LChunkBuilder::DoInvokeFunction(HInvokeFunction* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* function = UseFixed(instr->function(), edi);
-  argument_count_ -= instr->argument_count();
   LInvokeFunction* result = new(zone()) LInvokeFunction(context, function);
   return MarkAsCall(DefineFixed(result, eax), instr, CANNOT_DEOPTIMIZE_EAGERLY);
 }
@@ -1349,7 +1362,6 @@ LInstruction* LChunkBuilder::DoCallKeyed(HCallKeyed* instr) {
   ASSERT(instr->key()->representation().IsTagged());
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* key = UseFixed(instr->key(), ecx);
-  argument_count_ -= instr->argument_count();
   LCallKeyed* result = new(zone()) LCallKeyed(context, key);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
@@ -1357,7 +1369,6 @@ LInstruction* LChunkBuilder::DoCallKeyed(HCallKeyed* instr) {
 
 LInstruction* LChunkBuilder::DoCallNamed(HCallNamed* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
-  argument_count_ -= instr->argument_count();
   LCallNamed* result = new(zone()) LCallNamed(context);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
@@ -1365,14 +1376,12 @@ LInstruction* LChunkBuilder::DoCallNamed(HCallNamed* instr) {
 
 LInstruction* LChunkBuilder::DoCallGlobal(HCallGlobal* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
-  argument_count_ -= instr->argument_count();
   LCallGlobal* result = new(zone()) LCallGlobal(context);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
 
 
 LInstruction* LChunkBuilder::DoCallKnownGlobal(HCallKnownGlobal* instr) {
-  argument_count_ -= instr->argument_count();
   return MarkAsCall(DefineFixed(new(zone()) LCallKnownGlobal, eax), instr);
 }
 
@@ -1380,7 +1389,6 @@ LInstruction* LChunkBuilder::DoCallKnownGlobal(HCallKnownGlobal* instr) {
 LInstruction* LChunkBuilder::DoCallNew(HCallNew* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* constructor = UseFixed(instr->constructor(), edi);
-  argument_count_ -= instr->argument_count();
   LCallNew* result = new(zone()) LCallNew(context, constructor);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
@@ -1389,7 +1397,6 @@ LInstruction* LChunkBuilder::DoCallNew(HCallNew* instr) {
 LInstruction* LChunkBuilder::DoCallNewArray(HCallNewArray* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* constructor = UseFixed(instr->constructor(), edi);
-  argument_count_ -= instr->argument_count();
   LCallNewArray* result = new(zone()) LCallNewArray(context, constructor);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
@@ -1398,14 +1405,12 @@ LInstruction* LChunkBuilder::DoCallNewArray(HCallNewArray* instr) {
 LInstruction* LChunkBuilder::DoCallFunction(HCallFunction* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* function = UseFixed(instr->function(), edi);
-  argument_count_ -= instr->argument_count();
   LCallFunction* result = new(zone()) LCallFunction(context, function);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
 
 
 LInstruction* LChunkBuilder::DoCallRuntime(HCallRuntime* instr) {
-  argument_count_ -= instr->argument_count();
   LOperand* context = UseFixed(instr->context(), esi);
   return MarkAsCall(DefineFixed(new(zone()) LCallRuntime(context), eax), instr);
 }
@@ -1740,6 +1745,8 @@ LInstruction* LChunkBuilder::DoCompareNumericAndBranch(
 
 LInstruction* LChunkBuilder::DoCompareObjectEqAndBranch(
     HCompareObjectEqAndBranch* instr) {
+  LInstruction* goto_instr = CheckElideControlInstruction(instr);
+  if (goto_instr != NULL) return goto_instr;
   LOperand* left = UseRegisterAtStart(instr->left());
   LOperand* right = UseOrConstantAtStart(instr->right());
   return new(zone()) LCmpObjectEqAndBranch(left, right);
@@ -2415,7 +2422,11 @@ LInstruction* LChunkBuilder::DoStoreNamedField(HStoreNamedField* instr) {
       !(FLAG_track_double_fields && instr->field_representation().IsDouble());
 
   LOperand* val;
-  if (needs_write_barrier) {
+  if (instr->field_representation().IsByte()) {
+    // mov_b requires a byte register (i.e. any of eax, ebx, ecx, edx).
+    // Just force the value to be in eax and we're safe here.
+    val = UseFixed(instr->value(), eax);
+  } else if (needs_write_barrier) {
     val = UseTempRegister(instr->value());
   } else if (can_be_constant) {
     val = UseRegisterOrConstant(instr->value());
@@ -2562,7 +2573,6 @@ LInstruction* LChunkBuilder::DoUnknownOSRValue(HUnknownOSRValue* instr) {
 
 LInstruction* LChunkBuilder::DoCallStub(HCallStub* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
-  argument_count_ -= instr->argument_count();
   LCallStub* result = new(zone()) LCallStub(context);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
@@ -2691,7 +2701,7 @@ LInstruction* LChunkBuilder::DoLeaveInlined(HLeaveInlined* instr) {
   if (env->entry()->arguments_pushed()) {
     int argument_count = env->arguments_environment()->parameter_count();
     pop = new(zone()) LDrop(argument_count);
-    argument_count_ -= argument_count;
+    ASSERT(instr->argument_delta() == -argument_count);
   }
 
   HEnvironment* outer = current_block_->last_environment()->