Refactor FrameAndConstantPoolScope and ConstantPoolUnavailableScope to be architecture independent

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 5152fdc18291f7deb592ca85bde186d476139341..b8d55b04243ea8f3bbdb124c2a9720c03ff65b70 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -79,6 +79,16 @@ class AssemblerBase: public Malloced {
     return (enabled_cpu_features_ & (static_cast<uint64_t>(1) << f)) != 0;
   }
 
+  bool is_ool_constant_pool_available() const {
+    if (FLAG_enable_ool_constant_pool) {
+      return ool_constant_pool_available_;
+    } else {
+      // Out-of-line constant pool not supported on this architecture.
+      UNREACHABLE();
+      return false;
+    }
+  }
+
   // Overwrite a host NaN with a quiet target NaN.  Used by mksnapshot for
   // cross-snapshotting.
   static void QuietNaN(HeapObject* nan) { }
@@ -98,6 +108,15 @@ class AssemblerBase: public Malloced {
   int buffer_size_;
   bool own_buffer_;
 
+  void set_ool_constant_pool_available(bool available) {
+    if (FLAG_enable_ool_constant_pool) {
+      ool_constant_pool_available_ = available;
+    } else {
+      // Out-of-line constant pool not supported on this architecture.
+      UNREACHABLE();
+    }
+  }
+
   // The program counter, which points into the buffer above and moves forward.
   byte* pc_;
 
@@ -108,6 +127,14 @@ class AssemblerBase: public Malloced {
   bool emit_debug_code_;
   bool predictable_code_size_;
   bool serializer_enabled_;
+
+  // Indicates whether the constant pool can be accessed, which is only possible
+  // if the pp register points to the current code object's constant pool.
+  bool ool_constant_pool_available_;
+
+  // Constant pool.
+  friend class FrameAndConstantPoolScope;
+  friend class ConstantPoolUnavailableScope;
 };