Introduce FrameAndConstantPoolScope and ConstantPoolUnavailableScope.

src/arm/assembler-arm.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 1428 matching lines @@
   static const int kMaxNumPending32RelocInfo = kMaxDistToIntPool/kInstrSize;
   static const int kMaxNumPending64RelocInfo = kMaxDistToFPPool/kInstrSize;
 
   // Postpone the generation of the constant pool for the specified number of
   // instructions.
   void BlockConstPoolFor(int instructions);
 
   // Check if is time to emit a constant pool.
   void CheckConstPool(bool force_emit, bool require_jump);
 
+  bool can_use_constant_pool() const {
+    return is_constant_pool_available() && !constant_pool_full_;
+  }
+
+  void set_constant_pool_full() {
+    constant_pool_full_ = true;
+  }
+
  protected:
   // Relocation for a type-recording IC has the AST id added to it.  This
   // member variable is a way to pass the information from the call site to
   // the relocation info.
   TypeFeedbackId recorded_ast_id_;
 
   int buffer_space() const { return reloc_info_writer.pos() - pc_; }
 
   // Decode branch instruction at pos and return branch target pos
   int target_at(int pos);
@@ skipping 33 matching lines @@
       //    trigger a check.
       next_buffer_check_ = no_const_pool_before_;
     }
   }
 
   bool is_const_pool_blocked() const {
     return (const_pool_blocked_nesting_ > 0) ||
            (pc_offset() < no_const_pool_before_);
   }
 
+  bool is_constant_pool_available() const {
+    return constant_pool_available_;
+  }
+
+  void set_constant_pool_available(bool available) {
+    constant_pool_available_ = available;
+  }
+
  private:
   int next_buffer_check_;  // pc offset of next buffer check
 
   // Code generation
   // The relocation writer's position is at least kGap bytes below the end of
   // the generated instructions. This is so that multi-instruction sequences do
   // not have to check for overflow. The same is true for writes of large
   // relocation info entries.
   static const int kGap = 32;
 
@@ skipping 40 matching lines @@
   RelocInfo pending_32_bit_reloc_info_[kMaxNumPending32RelocInfo];
   RelocInfo pending_64_bit_reloc_info_[kMaxNumPending64RelocInfo];
   // Number of pending reloc info entries in the 32 bits buffer.
   int num_pending_32_bit_reloc_info_;
   // Number of pending reloc info entries in the 64 bits buffer.
   int num_pending_64_bit_reloc_info_;
 
   // The bound position, before this we cannot do instruction elimination.
   int last_bound_pos_;
 
+  bool constant_pool_available_;
+  bool constant_pool_full_;

[ulan, 2014/03/11 13:00:46]

Could you add a comment explaining what constant_pool_full_ indicates?

[rmcilroy, 2014/03/11 16:36:34]

Done (and for constant_pool_available)

+
   // Code emission
   inline void CheckBuffer();
   void GrowBuffer();
   inline void emit(Instr x);
 
   // 32-bit immediate values
   void move_32_bit_immediate(Condition cond,
                              Register rd,
                              SBit s,
                              const Operand& x);
@@ skipping 17 matching lines @@
 
   // Record reloc info for current pc_
   void RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data = 0,
                        UseConstantPoolMode mode = USE_CONSTANT_POOL);
   void RecordRelocInfo(double data);
   void RecordRelocInfoConstantPoolEntryHelper(const RelocInfo& rinfo);
 
   friend class RelocInfo;
   friend class CodePatcher;
   friend class BlockConstPoolScope;
+  friend class FrameAndConstantPoolScope;
+  friend class ConstantPoolUnavailableScope;
 
   PositionsRecorder positions_recorder_;
   friend class PositionsRecorder;
   friend class EnsureSpace;
 };
 
 
 class EnsureSpace BASE_EMBEDDED {
  public:
   explicit EnsureSpace(Assembler* assembler) {
     assembler->CheckBuffer();
   }
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_ASSEMBLER_ARM_H_