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 10namespace v8 { 11namespace internal { 12namespace compiler { 13 14// Forwards jumps to empty basic blocks that end with a second jump to the 15// destination of the second jump, transitively. 16class 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, bool frame_at_start); 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 34