Commit 9523d952 authored by Jan de Mooij's avatar Jan de Mooij
Browse files

Bug 1598548 part 12 - Don't treat JSOP_IFEQ as a backedge. r=arai 

Now all loops use either JSOP_IFNE (do-while) or JSOP_GOTO (other loops).

Differential Revision: https://phabricator.services.mozilla.com/D55723

--HG--
extra : moz-landing-system : lando
parent 3ef732aa

js/src/frontend/BytecodeControlStructures.h

+1 −1
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ class LoopControl : public BreakableControl { 
  //     {loop update if present}

  //

  //     # Loop end, backward jump

  //     JSOP_GOTO/JSOP_IFEQ/JSOP_IFNE head

  //     JSOP_GOTO/JSOP_IFNE head

  //

  //   breakTarget:

js/src/jit/IonBuilder.cpp

+3 −10
Original line number Diff line number Diff line
@@ -3112,7 +3112,7 @@ AbortReasonOr<Ok> IonBuilder::jsop_dup2() { 
}



AbortReasonOr<Ok> IonBuilder::visitTestBackedge(JSOp op, bool* restarted) {

  MOZ_ASSERT(op == JSOP_IFNE || op == JSOP_IFEQ);

  MOZ_ASSERT(op == JSOP_IFNE);

  MOZ_ASSERT(loopDepth_ > 0);



  MDefinition* ins = current->pop();
@@ -3128,15 +3128,8 @@ AbortReasonOr<Ok> IonBuilder::visitTestBackedge(JSOp op, bool* restarted) { 
  MBasicBlock* backedge;

  MOZ_TRY_VAR(backedge, newBlock(current, loopHead));



  if (op == JSOP_IFNE) {

  current->end(newTest(ins, backedge, nullptr));

    MOZ_TRY(

        addPendingEdge(PendingEdge::NewTestFalse(current, op), successorPC));

  } else {

    MOZ_ASSERT(op == JSOP_IFEQ);

    current->end(newTest(ins, nullptr, backedge));

    MOZ_TRY(addPendingEdge(PendingEdge::NewTestTrue(current, op), successorPC));

  }

  MOZ_TRY(addPendingEdge(PendingEdge::NewTestFalse(current, op), successorPC));



  MOZ_TRY(startTraversingBlock(backedge));

  return visitBackEdge(restarted);

js/src/vm/BytecodeUtil.h

+0 −1
Original line number Diff line number Diff line
@@ -274,7 +274,6 @@ static inline bool IsBackedgePC(jsbytecode* pc) { 
  switch (JSOp(*pc)) {

    case JSOP_GOTO:

    case JSOP_IFNE:

    case JSOP_IFEQ:

      return GET_JUMP_OFFSET(pc) < 0;

    default:

      return false;