CodeGen: Fix assertion in machine inst sheduler due to llvm.dbg.value

Two issues were found about machine inst scheduler when compiling ProRender
with -g for amdgcn target:

GCNScheduleDAGMILive::schedule tries to update LiveIntervals for DBG_VALUE, which it
should not since DBG_VALUE is not mapped in LiveIntervals.

when DBG_VALUE is the last instruction of MBB, ScheduleDAGInstrs::buildSchedGraph and
ScheduleDAGMILive::scheduleMI does not move RPTracker properly, which causes assertion.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D41132

llvm-svn: 320650

1 files changed, 11 insertions, 8 deletions

diff --git a/llvm/lib/Target/AMDGPU/GCNSchedStrategy.cpp b/llvm/lib/Target/AMDGPU/GCNSchedStrategy.cpp
index b325a49e11f..0e80e936ab8 100644
--- a/llvm/lib/Target/AMDGPU/GCNSchedStrategy.cpp
+++ b/llvm/lib/Target/AMDGPU/GCNSchedStrategy.cpp
@@ -394,7 +394,8 @@ void GCNScheduleDAGMILive::schedule() {
     if (MI->getIterator() != RegionEnd) {
       BB->remove(MI);
       BB->insert(RegionEnd, MI);
-      LIS->handleMove(*MI, true);
+      if (!MI->isDebugValue())
+        LIS->handleMove(*MI, true);
     }
     // Reset read-undef flags and update them later.
     for (auto &Op : MI->operands())
@@ -402,13 +403,15 @@ void GCNScheduleDAGMILive::schedule() {
         Op.setIsUndef(false);
     RegisterOperands RegOpers;
     RegOpers.collect(*MI, *TRI, MRI, ShouldTrackLaneMasks, false);
-    if (ShouldTrackLaneMasks) {
-      // Adjust liveness and add missing dead+read-undef flags.
-      SlotIndex SlotIdx = LIS->getInstructionIndex(*MI).getRegSlot();
-      RegOpers.adjustLaneLiveness(*LIS, MRI, SlotIdx, MI);
-    } else {
-      // Adjust for missing dead-def flags.
-      RegOpers.detectDeadDefs(*MI, *LIS);
+    if (!MI->isDebugValue()) {
+      if (ShouldTrackLaneMasks) {
+        // Adjust liveness and add missing dead+read-undef flags.
+        SlotIndex SlotIdx = LIS->getInstructionIndex(*MI).getRegSlot();
+        RegOpers.adjustLaneLiveness(*LIS, MRI, SlotIdx, MI);
+      } else {
+        // Adjust for missing dead-def flags.
+        RegOpers.detectDeadDefs(*MI, *LIS);
+      }
     }
     RegionEnd = MI->getIterator();
     ++RegionEnd;