Update domination chain and RPO manually in MaybeAddExtraGotoBlocks

There's no need to recompute the whole graph as we know what changed.

As a drive-by, we now don't return false for graphs with irreducible
loops so we can remove that restriction from the builder. However,
if a graph with irreducible loops hits this path it means that:
  A) it's being inlined
  B) Has irreducible loops

We don't inline graphs with irreducible loops, and after building
for inline we don't remove them either because constant folding
and instruction simplifier don't remove them, and DCE doesn't
run for graphs with irreducible loops. So, in terms of dex2oat's
outputs nothing should change.

Test: art/test/testrunner/testrunner.py --host --64 --optimizing -b
Change-Id: I8cbf1b5f0518bb5dd14ffd751100ea81f5478863

1 files changed, 5 insertions, 1 deletions

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 006ccfb8ec..591087bae6 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -138,7 +138,6 @@ enum GraphAnalysisResult {
   kAnalysisInvalidBytecode,
   kAnalysisFailThrowCatchLoop,
   kAnalysisFailAmbiguousArrayOp,
-  kAnalysisFailInliningIrreducibleLoop,
   kAnalysisFailIrreducibleLoopAndStringInit,
   kAnalysisFailPhiEquivalentInOsr,
   kAnalysisSuccess,
@@ -515,6 +514,11 @@ class HGraph : public ArenaObject<kArenaAllocGraph> {
   HBasicBlock* SplitEdge(HBasicBlock* block, HBasicBlock* successor);
 
   void SplitCriticalEdge(HBasicBlock* block, HBasicBlock* successor);
+
+  // Splits the edge between `block` and `successor` and then updates the graph's RPO to keep
+  // consistency without recomputing the whole graph.
+  HBasicBlock* SplitEdgeAndUpdateRPO(HBasicBlock* block, HBasicBlock* successor);
+
   void OrderLoopHeaderPredecessors(HBasicBlock* header);
 
   // Transform a loop into a format with a single preheader.