diff options
Diffstat (limited to 'js/src/jit/BacktrackingAllocator.cpp')
| -rw-r--r-- | js/src/jit/BacktrackingAllocator.cpp | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/js/src/jit/BacktrackingAllocator.cpp b/js/src/jit/BacktrackingAllocator.cpp index 73aceeccb..645aefc4f 100644 --- a/js/src/jit/BacktrackingAllocator.cpp +++ b/js/src/jit/BacktrackingAllocator.cpp @@ -1736,6 +1736,18 @@ BacktrackingAllocator::deadRange(LiveRange* range) } bool +BacktrackingAllocator::moveAtEdge(LBlock* predecessor, LBlock* successor, LiveRange* from, + LiveRange* to, LDefinition::Type type) +{ + if (successor->mir()->numPredecessors() > 1) { + MOZ_ASSERT(predecessor->mir()->numSuccessors() == 1); + return moveAtExit(predecessor, from, to, type); + } + + return moveAtEntry(successor, from, to, type); +} + +bool BacktrackingAllocator::resolveControlFlow() { // Add moves to handle changing assignments for vregs over their lifetime. @@ -1843,10 +1855,15 @@ BacktrackingAllocator::resolveControlFlow() LiveRange* from = vreg(input).rangeFor(exitOf(predecessor), /* preferRegister = */ true); MOZ_ASSERT(from); - if (!alloc().ensureBallast()) + if (!alloc().ensureBallast()) { return false; - if (!moveAtExit(predecessor, from, to, def->type())) + } + + // Note: we have to use moveAtEdge both here and below (for edge + // resolution) to avoid conflicting moves. See bug 1493900. + if (!moveAtEdge(predecessor, successor, from, to, def->type())) { return false; + } } } } @@ -1875,16 +1892,12 @@ BacktrackingAllocator::resolveControlFlow() if (targetRange->covers(exitOf(predecessor))) continue; - if (!alloc().ensureBallast()) + if (!alloc().ensureBallast()) { return false; + } LiveRange* from = reg.rangeFor(exitOf(predecessor), true); - if (successor->mir()->numPredecessors() > 1) { - MOZ_ASSERT(predecessor->mir()->numSuccessors() == 1); - if (!moveAtExit(predecessor, from, targetRange, reg.type())) - return false; - } else { - if (!moveAtEntry(successor, from, targetRange, reg.type())) - return false; + if (!moveAtEdge(predecessor, successor, from, targetRange, reg.type())) { + return false; } } } |