[heap] Remove max executable size configuration.

src/ppc/assembler-ppc.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 1420 matching lines @@
   // 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 constexpr int kGap = 32;
 
   RelocInfoWriter reloc_info_writer;
 
  private:
+  // Avoid overflows for displacements etc.
+  static const int kMaximalBufferSize = 512 * MB;
+
   // Repeated checking whether the trampoline pool should be emitted is rather
   // expensive. By default we only check again once a number of instructions
   // has been generated.
   int next_trampoline_check_;  // pc offset of next buffer check.
 
   // Emission of the trampoline pool may be blocked in some code sequences.
   int trampoline_pool_blocked_nesting_;  // Block emission if this is not zero.
   int no_trampoline_pool_before_;  // Block emission before this pc offset.
 
   // Do not share constant pool entries.
@@ skipping 103 matching lines @@
   PatchingAssembler(IsolateData isolate_data, byte* address, int instructions);
   ~PatchingAssembler();
 
   void FlushICache(Isolate* isolate);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PPC_ASSEMBLER_PPC_H_