Faster filling newly allocated arrays with the holes from the Array construction stub.

src/ia32/assembler-ia32.cc

 // 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 735 matching lines @@
   ASSERT(CpuFeatures::IsEnabled(CMOV));
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // Opcode: 0f 40 + cc /r.
   EMIT(0x0F);
   EMIT(0x40 + cc);
   emit_operand(dst, src);
 }
 
 
+void Assembler::cld() {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  EMIT(0xFC);
+}
+
+
 void Assembler::rep_movs() {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0xA5);
 }
 
 
+void Assembler::rep_stos() {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  EMIT(0xF3);
+  EMIT(0xAB);
+}
+
+
 void Assembler::xchg(Register dst, Register src) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   if (src.is(eax) || dst.is(eax)) {  // Single-byte encoding.
     EMIT(0x90 | (src.is(eax) ? dst.code() : src.code()));
   } else {
     EMIT(0x87);
     EMIT(0xC0 | src.code() << 3 | dst.code());
   }
 }
@@ skipping 1716 matching lines @@
   push_insn[1] = 13;    // Skip over coverage insns.
   if (coverage_log != NULL) {
     fprintf(coverage_log, "%s\n", file_line);
     fflush(coverage_log);
   }
 }
 
 #endif
 
 } }  // namespace v8::internal