[turbofan] OSR loops assign all local variables.

src/bit-vector.h

 // Copyright 2012 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_DATAFLOW_H_
 #define V8_DATAFLOW_H_
 
 #include "src/v8.h"
 
 #include "src/allocation.h"
@@ skipping 85 matching lines @@
     DCHECK(i >= 0 && i < length());
     uintptr_t block = data_[i / kDataBits];
     return (block & (kOne << (i % kDataBits))) != 0;
   }
 
   void Add(int i) {
     DCHECK(i >= 0 && i < length());
     data_[i / kDataBits] |= (kOne << (i % kDataBits));
   }
 
+  void AddAll() { memset(data_, -1, sizeof(uintptr_t) * data_length_); }
+
   void Remove(int i) {
     DCHECK(i >= 0 && i < length());
     data_[i / kDataBits] &= ~(kOne << (i % kDataBits));
   }
 
   void Union(const BitVector& other) {
     DCHECK(other.length() == length());
     for (int i = 0; i < data_length_; i++) {
       data_[i] |= other.data_[i];
     }
@@ skipping 29 matching lines @@
   }
 
   void Subtract(const BitVector& other) {
     DCHECK(other.length() == length());
     for (int i = 0; i < data_length_; i++) {
       data_[i] &= ~other.data_[i];
     }
   }
 
   void Clear() {
     for (int i = 0; i < data_length_; i++) {

[Michael Starzinger, 2015/02/06 14:59:32]

Just out of curiosity, is there a reason Clear doesn't use memset here?

[titzer, 2015/02/06 15:01:54]

No idea. I can fix it, if you like. I did the memset above because I wasn't sure
that static_cast<uintptr_t>(-1) was a good idea, so I used the big hammer.

       data_[i] = 0;
     }
   }
 
   bool IsEmpty() const {
     for (int i = 0; i < data_length_; i++) {
       if (data_[i] != 0) return false;
     }
     return true;
   }
@@ skipping 77 matching lines @@
     bits_ = new_bits;
   }
 
   BitVector* bits_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DATAFLOW_H_