[heap] Remove max executable size configuration.

src/arm64/assembler-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_ASSEMBLER_ARM64_H_
 #define V8_ARM64_ASSEMBLER_ARM64_H_
 
 #include <deque>
 #include <list>
 #include <map>
@@ skipping 2116 matching lines @@
     DCHECK(!unresolved_branches_.empty());
     return unresolved_branches_.begin()->first;
   }
   // This is similar to next_constant_pool_check_ and helps reduce the overhead
   // of checking for veneer pools.
   // It is maintained to the closest unresolved branch limit minus the maximum
   // veneer margin (or kMaxInt if there are no unresolved branches).
   int next_veneer_pool_check_;
 
  private:
+  // Avoid overflows for displacements etc.
+  static const int kMaximalBufferSize = 512 * MB;
+
   // If a veneer is emitted for a branch instruction, that instruction must be
   // removed from the associated label's link chain so that the assembler does
   // not later attempt (likely unsuccessfully) to patch it to branch directly to
   // the label.
   void DeleteUnresolvedBranchInfoForLabel(Label* label);
   // This function deletes the information related to the label by traversing
   // the label chain, and for each PC-relative instruction in the chain checking
   // if pending unresolved information exists. Its complexity is proportional to
   // the length of the label chain.
   void DeleteUnresolvedBranchInfoForLabelTraverse(Label* label);
@@ skipping 56 matching lines @@
  public:
   explicit EnsureSpace(Assembler* assembler) {
     assembler->CheckBufferSpace();
   }
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM64_ASSEMBLER_ARM64_H_