[llvm] r298861 - [AMDGPU] SISched: Update colorEndsAccordingToDependencies

[Valery Pykhtin via llvm-commits]

Author: vpykhtin
Date: Mon Mar 27 12:26:40 2017
New Revision: 298861

URL: http://llvm.org/viewvc/llvm-project?rev=298861&view=rev
Log:
[AMDGPU] SISched: Update colorEndsAccordingToDependencies

Patch by Axel Davy (axel.davy at normalesup.org)

Differential revision: https://reviews.llvm.org/D30150

Modified:
    llvm/trunk/lib/Target/AMDGPU/SIMachineScheduler.cpp

Modified: llvm/trunk/lib/Target/AMDGPU/SIMachineScheduler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/SIMachineScheduler.cpp?rev=298861&r1=298860&r2=298861&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/SIMachineScheduler.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/SIMachineScheduler.cpp Mon Mar 27 12:26:40 2017
@@ -835,6 +835,17 @@ void SIScheduleBlockCreator::colorEndsAc
   unsigned DAGSize = DAG->SUnits.size();
   std::vector<int> PendingColoring = CurrentColoring;
 
+  assert(DAGSize >= 1 &&
+         CurrentBottomUpReservedDependencyColoring.size() == DAGSize &&
+         CurrentTopDownReservedDependencyColoring.size() == DAGSize);
+  // If there is no reserved block at all, do nothing. We don't want
+  // everything in one block.
+  if (*std::max_element(CurrentBottomUpReservedDependencyColoring.begin(),
+                        CurrentBottomUpReservedDependencyColoring.end()) == 0 &&
+      *std::max_element(CurrentTopDownReservedDependencyColoring.begin(),
+                        CurrentTopDownReservedDependencyColoring.end()) == 0)
+    return;
+
   for (unsigned SUNum : DAG->BottomUpIndex2SU) {
     SUnit *SU = &DAG->SUnits[SUNum];
     std::set<unsigned> SUColors;
@@ -856,6 +867,9 @@ void SIScheduleBlockCreator::colorEndsAc
         SUColors.insert(CurrentColoring[Succ->NodeNum]);
       SUColorsPending.insert(PendingColoring[Succ->NodeNum]);
     }
+    // If there is only one child/parent block, and that block
+    // is not among the ones we are removing in this path, then
+    // merge the instruction to that block
     if (SUColors.size() == 1 && SUColorsPending.size() == 1)
       PendingColoring[SU->NodeNum] = *SUColors.begin();
     else // TODO: Attribute new colors depending on color