Changes in directory llvm/lib/CodeGen/SelectionDAG:
ScheduleDAGList.cpp updated: 1.18 -> 1.19 --- Log message: update file comment --- Diffs of the changes: (+8 -3) ScheduleDAGList.cpp | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-) Index: llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp diff -u llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp:1.18 llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp:1.19 --- llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp:1.18 Mon Mar 6 01:31:44 2006 +++ llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp Mon Mar 6 11:58:04 2006 @@ -7,9 +7,14 @@ // //===----------------------------------------------------------------------===// // -// This implements a simple two pass scheduler. The first pass attempts to push -// backward any lengthy instructions and critical paths. The second pass packs -// instructions into semi-optimal time slots. +// This implements bottom-up and top-down list schedulers, using standard +// algorithms. The basic approach uses a priority queue of available nodes to +// schedule. One at a time, nodes are taken from the priority queue (thus in +// priority order), checked for legality to schedule, and emitted if legal. +// +// Nodes may not be legal to schedule either due to structural hazards (e.g. +// pipeline or resource constraints) or because an input to the instruction has +// not completed execution. // //===----------------------------------------------------------------------===// _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits