Assert that all trace candidate blocks have been visited by the PO.
When computing a trace, all the candidates for pred/succ must have been
visited. Filter out back-edges first, though. The PO traversal ignores
them.
Thanks to Andy for spotting this in review.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160995 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineTraceMetrics.cpp b/lib/CodeGen/MachineTraceMetrics.cpp
index c31e6bd..64f4a95 100644
--- a/lib/CodeGen/MachineTraceMetrics.cpp
+++ b/lib/CodeGen/MachineTraceMetrics.cpp
@@ -214,15 +214,12 @@
for (MachineBasicBlock::const_pred_iterator
I = MBB->pred_begin(), E = MBB->pred_end(); I != E; ++I) {
const MachineBasicBlock *Pred = *I;
- const MachineTraceMetrics::TraceBlockInfo *PredTBI =
- getDepthResources(Pred);
- // Ignore invalidated predecessors. This never happens on the first scan,
- // but if we rejected this predecessor earlier, it won't be revalidated.
- if (!PredTBI)
- continue;
// Don't consider predecessors in other loops.
if (getLoopFor(Pred) != CurLoop)
continue;
+ const MachineTraceMetrics::TraceBlockInfo *PredTBI =
+ getDepthResources(Pred);
+ assert(PredTBI && "Predecessor must be visited first");
// Pick the predecessor that would give this block the smallest InstrDepth.
unsigned Depth = PredTBI->InstrDepth + CurCount;
if (!Best || Depth < BestDepth)
@@ -242,17 +239,15 @@
for (MachineBasicBlock::const_succ_iterator
I = MBB->succ_begin(), E = MBB->succ_end(); I != E; ++I) {
const MachineBasicBlock *Succ = *I;
- const MachineTraceMetrics::TraceBlockInfo *SuccTBI =
- getHeightResources(Succ);
- // Ignore invalidated successors.
- if (!SuccTBI)
- continue;
// Don't consider back-edges.
if (CurLoop && Succ == CurLoop->getHeader())
continue;
// Don't consider successors in other loops.
if (getLoopFor(Succ) != CurLoop)
continue;
+ const MachineTraceMetrics::TraceBlockInfo *SuccTBI =
+ getHeightResources(Succ);
+ assert(SuccTBI && "Successor must be visited first");
// Pick the successor that would give this block the smallest InstrHeight.
unsigned Height = SuccTBI->InstrHeight;
if (!Best || Height < BestHeight)