PPC: [turbofan] Enable tail calls for %_CallRuntime.

src/compiler/ppc/code-generator-ppc.cc

 // Copyright 2014 the V8 project authors. 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/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/ppc/macro-assembler-ppc.h"
@@ skipping 567 matching lines @@
     LinkRegisterStatus lr_status = kLRHasNotBeenSaved;                         \
     __ RecordWrite(object, index, value, lr_status, mode);                     \
     DCHECK_EQ(LeaveRC, i.OutputRCBit());                                       \
   } while (0)
 
 
 void CodeGenerator::AssembleDeconstructActivationRecord() {
   CallDescriptor* descriptor = linkage()->GetIncomingDescriptor();
   int stack_slots = frame()->GetSpillSlotCount();
   if (descriptor->IsJSFunctionCall() || stack_slots > 0) {
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ LeaveFrame(StackFrame::MANUAL, pop_count * kPointerSize);
+    __ LeaveFrame(StackFrame::MANUAL);
   }
 }
 
 
 // Assembles an instruction after register allocation, producing machine code.
 void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
   PPCOperandConverter i(this, instr);
   ArchOpcode opcode = ArchOpcodeField::decode(instr->opcode());
 
   switch (opcode) {
@@ skipping 11 matching lines @@
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
     }
     case kArchTailCallCodeObject: {
       AssembleDeconstructActivationRecord();
       if (HasRegisterInput(instr, 0)) {
         __ addi(ip, i.InputRegister(0),
                 Operand(Code::kHeaderSize - kHeapObjectTag));
         __ Jump(ip);
       } else {
+        // We cannot use the constant pool to load the target since
+        // we've already restored the caller's frame.
+        ConstantPoolUnavailableScope constant_pool_unavailable(masm());
         __ Jump(Handle<Code>::cast(i.InputHeapObject(0)),
                 RelocInfo::CODE_TARGET);
       }
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
     }
     case kArchCallJSFunction: {
       EnsureSpaceForLazyDeopt();
       Register func = i.InputRegister(0);
       if (FLAG_debug_code) {
@@ skipping 739 matching lines @@
     __ LeaveFrame(StackFrame::MANUAL);
     __ Ret();
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
     // Canonicalize JSFunction return sites for now.
     if (return_label_.is_bound()) {
       __ b(&return_label_);
     } else {
       __ bind(&return_label_);
       int pop_count = descriptor->IsJSFunctionCall()
                           ? static_cast<int>(descriptor->JSParameterCount())
-                          : 0;
+                          : (info()->IsStub()
+                                 ? info()->code_stub()->GetStackParameterCount()
+                                 : 0);
       __ LeaveFrame(StackFrame::MANUAL, pop_count * kPointerSize);
       __ Ret();
     }
   } else {
     __ Ret();
   }
 }
 
 
 void CodeGenerator::AssembleMove(InstructionOperand* source,
@@ skipping 194 matching lines @@
       }
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8