ARM64: use jssp for stack slots

src/arm64/lithium-codegen-arm64.h

 // Copyright 2013 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.
 
 #ifndef V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
 #define V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
 
 #include "arm64/lithium-arm64.h"
 
 #include "arm64/lithium-gap-resolver-arm64.h"
@@ skipping 19 matching lines @@
         deopt_jump_table_(4, info->zone()),
         deoptimization_literals_(8, info->zone()),
         inlined_function_count_(0),
         scope_(info->scope()),
         translations_(info->zone()),
         deferred_(8, info->zone()),
         osr_pc_offset_(-1),
         frame_is_built_(false),
         safepoints_(info->zone()),
         resolver_(this),
-        expected_safepoint_kind_(Safepoint::kSimple) {
+        expected_safepoint_kind_(Safepoint::kSimple),
+        after_push_argument_(false),
+        inlined_arguments_(false) {
     PopulateDeoptimizationLiteralsWithInlinedFunctions();
   }
 
+  ~LCodeGen() {
+    ASSERT(!after_push_argument_ || inlined_arguments_);
+  }
+
   // Simple accessors.
   Scope* scope() const { return scope_; }
 
   int LookupDestination(int block_id) const {
     return chunk()->LookupDestination(block_id);
   }
 
   bool IsNextEmittedBlock(int block_id) const {
     return LookupDestination(block_id) == GetNextEmittedBlock();
   }
@@ skipping 21 matching lines @@
   // information on it.
   void FinishCode(Handle<Code> code);
 
   // Support for converting LOperands to assembler types.
   // LOperand must be a register.
   Register ToRegister(LOperand* op) const;
   Register ToRegister32(LOperand* op) const;
   Operand ToOperand(LOperand* op);
   Operand ToOperand32I(LOperand* op);
   Operand ToOperand32U(LOperand* op);
-  MemOperand ToMemOperand(LOperand* op) const;
+  enum StackMode { kMustUseFramePointer, kCanUseStackPointer };
+  MemOperand ToMemOperand(LOperand* op,
+                          StackMode stack_mode = kCanUseStackPointer) const;
   Handle<Object> ToHandle(LConstantOperand* op) const;
 
   // TODO(jbramley): Examine these helpers and check that they make sense.
   // IsInteger32Constant returns true for smi constants, for example.
   bool IsInteger32Constant(LConstantOperand* op) const;
   bool IsSmi(LConstantOperand* op) const;
 
   int32_t ToInteger32(LConstantOperand* op) const;
   Smi* ToSmi(LConstantOperand* op) const;
   double ToDouble(LConstantOperand* op) const;
@@ skipping 245 matching lines @@
 
   // Builder that keeps track of safepoints in the code. The table itself is
   // emitted at the end of the generated code.
   SafepointTableBuilder safepoints_;
 
   // Compiler from a set of parallel moves to a sequential list of moves.
   LGapResolver resolver_;
 
   Safepoint::Kind expected_safepoint_kind_;
 
+  // This flag is true when we are after a push (but before a call).
+  // In this situation, jssp no longer references the end of the stack slots so,
+  // we can only reference a stack slot via fp.
+  bool after_push_argument_;
+  // If we have inlined arguments, we are no longer able to use jssp because
+  // jssp is modified and we never know if we are in a block after or before
+  // the pop of the arguments (which restores jssp).
+  bool inlined_arguments_;
+
   int old_position_;
 
   class PushSafepointRegistersScope BASE_EMBEDDED {
    public:
     PushSafepointRegistersScope(LCodeGen* codegen,
                                 Safepoint::Kind kind)
         : codegen_(codegen) {
       ASSERT(codegen_->info()->is_calling());
       ASSERT(codegen_->expected_safepoint_kind_ == Safepoint::kSimple);
       codegen_->expected_safepoint_kind_ = kind;
@@ skipping 100 matching lines @@
 
  protected:
   MacroAssembler* masm() const { return codegen_->masm(); }
 
   LCodeGen* codegen_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_