deps/v8/src/compiler/jump-threading.h

   1 // Copyright 2014 the V8 project authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef V8_COMPILER_JUMP_THREADING_H_
   6 #define V8_COMPILER_JUMP_THREADING_H_
   7
   8 #include "src/compiler/instruction.h"
   9
  10 namespace v8 {
  11 namespace internal {
  12 namespace compiler {
  13
  14 // Forwards jumps to empty basic blocks that end with a second jump to the
  15 // destination of the second jump, transitively.
  16 class JumpThreading {
  17  public:
  18   // Compute the forwarding map of basic blocks to their ultimate destination.
  19   // Returns {true} if there is at least one block that is forwarded.
  20   static bool ComputeForwarding(Zone* local_zone, ZoneVector<RpoNumber>& result,
  21                                 InstructionSequence* code);
  22
  23   // Rewrite the instructions to forward jumps and branches.
  24   // May also negate some branches.
  25   static void ApplyForwarding(ZoneVector<RpoNumber>& forwarding,
  26                               InstructionSequence* code);
  27 };
  28
  29 }  // namespace compiler
  30 }  // namespace internal
  31 }  // namespace v8
  32
  33 #endif  // V8_COMPILER_JUMP_THREADING_H