if (VM.VerifyAssertions) VM.assert(vp.modifiedOldObjectsTop==vp.modifiedOldObjectsMax);
if (VM.VerifyAssertions) VM._assert(vp.modifiedOldObjectsTop==vp.modifiedOldObjectsMax);
  static void growWriteBuffer() throws VM_PragmaUninterruptible {    VM_Processor vp = VM_Processor.getCurrentProcessor();    if (VM.VerifyAssertions) VM.assert(vp.modifiedOldObjectsTop==vp.modifiedOldObjectsMax);    VM_Address newBufAddr = VM_Address.fromInt(VM.sysCall1(VM_BootRecord.the_boot_record.sysMallocIP,							   WRITE_BUFFER_SIZE));    if (newBufAddr.isZero()) {      VM.sysWrite(" In growWriteBuffer, call to sysMalloc returned 0 \n");      VM.sysExit(1800);    }    // set last word in current buffer to address of next buffer    VM_Magic.setMemoryAddress(vp.modifiedOldObjectsTop.add(4), newBufAddr);    // set fptr in new buffer to null, to identify it as last    VM_Magic.setMemoryWord(newBufAddr.add(WRITE_BUFFER_SIZE-4),0);    // set writebuffer pointers in processor object for stores into new buffer    vp.modifiedOldObjectsTop = newBufAddr.sub(4);    vp.modifiedOldObjectsMax = newBufAddr.add(WRITE_BUFFER_SIZE - 8);  }