EXTRACT_SUBREG coalescing support. The coalescer now treats EXTRACT_SUBREG like

[oota-llvm.git] / lib / CodeGen / SelectionDAG / ScheduleDAGRRList.cpp

diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
index c1a85096157d29168621cf4356690236d683eb8c..2baf24d7d54b33235406353ac37d57ff2f681021 100644 (file)
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
@@ -1097,6 +1097,11 @@ namespace {
         // CopyToReg should be close to its uses to facilitate coalescing and
         // avoid spilling.
         return 0;
+      else if (Opc == TargetInstrInfo::EXTRACT_SUBREG ||
+               Opc == TargetInstrInfo::INSERT_SUBREG)
+        // EXTRACT_SUBREG / INSERT_SUBREG should be close to its use to
+        // facilitate coalescing.
+        return 0;
       else if (SU->NumSuccs == 0)
         // If SU does not have a use, i.e. it doesn't produce a value that would
         // be consumed (e.g. store), then it terminates a chain of computation.
@@ -1308,6 +1313,14 @@ void BURegReductionPriorityQueue<SF>::AddPseudoTwoAddrDeps() {
           // Be conservative. Ignore if nodes aren't at the same depth.
           if (SuccSU->Depth != SU->Depth)
             continue;
+          if (!SuccSU->Node || !SuccSU->Node->isTargetOpcode())
+            continue;
+          // Don't constraint extract_subreg / insert_subreg these may be
+          // coalesced away. We don't them close to their uses.
+          unsigned SuccOpc = SuccSU->Node->getTargetOpcode();
+          if (SuccOpc == TargetInstrInfo::EXTRACT_SUBREG ||
+              SuccOpc == TargetInstrInfo::INSERT_SUBREG)
+            continue;
           if ((!canClobber(SuccSU, DUSU) ||
                (hasCopyToRegUse(SU) && !hasCopyToRegUse(SuccSU)) ||
                (!SU->isCommutable && SuccSU->isCommutable)) &&