diff options
Diffstat (limited to 'llvm/lib/CodeGen/MacroFusion.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MacroFusion.cpp | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/MacroFusion.cpp b/llvm/lib/CodeGen/MacroFusion.cpp index 26cbc14166b..d2ee21c8720 100644 --- a/llvm/lib/CodeGen/MacroFusion.cpp +++ b/llvm/lib/CodeGen/MacroFusion.cpp @@ -71,6 +71,14 @@ static bool fuseInstructionPair(ScheduleDAGInstrs &DAG, SUnit &FirstSU, if (!DAG.addEdge(&SecondSU, SDep(&FirstSU, SDep::Cluster))) return false; + // TODO - If we want to chain more than two instructions, we need to create + // artifical edges to make dependencies from the FirstSU also dependent + // on other chained instructions, and other chained instructions also + // dependent on the dependencies of the SecondSU, to prevent them from being + // scheduled into these chained instructions. + assert(hasLessThanNumFused(FirstSU, 2) && + "Currently we only support chaining together two instructions"); + // Adjust the latency between both instrs. for (SDep &SI : FirstSU.Succs) if (SI.getSUnit() == &SecondSU) |
