Align code entry points to 32 bytes.

src/heap.cc

 // Copyright 2006-2008 the V8 project authors. 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.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1613 matching lines @@
 
 Object* Heap::CreateCode(const CodeDesc& desc,
                          ScopeInfo<>* sinfo,
                          Code::Flags flags,
                          Handle<Object> self_reference) {
   // Compute size
   int body_size = RoundUp(desc.instr_size + desc.reloc_size, kObjectAlignment);
   int sinfo_size = 0;
   if (sinfo != NULL) sinfo_size = sinfo->Serialize(NULL);
   int obj_size = Code::SizeFor(body_size, sinfo_size);
+  ASSERT((obj_size % Code::kCodeAlignment) == 0);

[Kasper Lund, 2009/02/27 10:32:11]

IsAligned(obj_size, Code::kCodeAlignment) would be easier to read.

[iposva, 2009/02/27 11:08:28]

Done.

   Object* result;
   if (obj_size > MaxHeapObjectSize()) {
     result = lo_space_->AllocateRawCode(obj_size);
   } else {
     result = code_space_->AllocateRaw(obj_size);
   }
 
   if (result->IsFailure()) return result;
 
   // Initialize the object
@@ skipping 14 matching lines @@
   // that are dereferenced during the copy to point directly to the actual heap
   // objects. These pointers can include references to the code object itself,
   // through the self_reference parameter.
   code->CopyFrom(desc);
   if (sinfo != NULL) sinfo->Serialize(code);  // write scope info
   LOG(CodeAllocateEvent(code, desc.origin));
 
 #ifdef DEBUG
   code->Verify();
 #endif
   return code;

[Kasper Lund, 2009/02/27 10:32:11]

It would be nice if you could assert that the entry point (instruction start) is
aligned the way you want it.

[iposva, 2009/02/27 11:08:28]

Done now as part of CodeVerify().

 }
 
 
 Object* Heap::CopyCode(Code* code) {
   // Allocate an object the same size as the code object.
   int obj_size = code->Size();
   Object* result;
   if (obj_size > MaxHeapObjectSize()) {
     result = lo_space_->AllocateRawCode(obj_size);
   } else {
@@ skipping 1646 matching lines @@
 #ifdef DEBUG
 bool Heap::GarbageCollectionGreedyCheck() {
   ASSERT(FLAG_gc_greedy);
   if (Bootstrapper::IsActive()) return true;
   if (disallow_allocation_failure()) return true;
   return CollectGarbage(0, NEW_SPACE);
 }
 #endif
 
 } }  // namespace v8::internal