ART: Fix missing dependency between GVN and other passes

The GVN may be turned off completely, or skip running when the
method is too complex. Turn off DCE in that case.

The dependent cleanup pass is not an optimization pass, so can't be
turned off that way. Check whether the GVN skipped in the gate function.

A possible follow-up is proper dependencies between passes.

Change-Id: I5b7951ecd6c74ebbfa5b23726a3d2f3ea1a23a47

3 files changed, 20 insertions, 1 deletions

diff --git a/compiler/dex/bb_optimizations.cc b/compiler/dex/bb_optimizations.cc
index 11a7e44f98..f351d990d0 100644
--- a/compiler/dex/bb_optimizations.cc
+++ b/compiler/dex/bb_optimizations.cc
@@ -17,6 +17,7 @@
 #include "bb_optimizations.h"
 #include "dataflow_iterator.h"
 #include "dataflow_iterator-inl.h"
+#include "global_value_numbering.h"
 
 namespace art {
 
@@ -79,4 +80,14 @@ bool MethodUseCount::Worker(PassDataHolder* data) const {
   return false;
 }
 
+bool GlobalValueNumberingCleanupPass::Gate(const PassDataHolder* data) const {
+  DCHECK(data != nullptr);
+  CompilationUnit* c_unit = down_cast<const PassMEDataHolder*>(data)->c_unit;
+  DCHECK(c_unit != nullptr);
+  // Do not do cleanup if GVN skipped this.
+  // TODO: Proper dependencies between passes?
+  return !GlobalValueNumbering::Skip(c_unit);
+}
+
+
 }  // namespace art
diff --git a/compiler/dex/bb_optimizations.h b/compiler/dex/bb_optimizations.h
index eb87c29f9d..b948afd605 100644
--- a/compiler/dex/bb_optimizations.h
+++ b/compiler/dex/bb_optimizations.h
@@ -284,6 +284,9 @@ class GlobalValueNumberingCleanupPass : public PassME {
     : PassME("GVNCleanup", kNoNodes, "") {
   }
 
+  // Depends on GlobalValueNumbering, so implemented in cc file.
+  bool Gate(const PassDataHolder* data) const OVERRIDE;
+
   void Start(PassDataHolder* data) const OVERRIDE {
     DCHECK(data != nullptr);
     CompilationUnit* c_unit = down_cast<const PassMEDataHolder*>(data)->c_unit;
diff --git a/compiler/dex/mir_optimization.cc b/compiler/dex/mir_optimization.cc
index 0d5da32d6d..3482602704 100644
--- a/compiler/dex/mir_optimization.cc
+++ b/compiler/dex/mir_optimization.cc
@@ -1355,8 +1355,13 @@ void MIRGraph::EliminateClassInitChecksEnd() {
   temp_scoped_alloc_.reset();
 }
 
+static void DisableGVNDependentOptimizations(CompilationUnit* cu) {
+  cu->disable_opt |= (1u << kGvnDeadCodeElimination);
+}
+
 bool MIRGraph::ApplyGlobalValueNumberingGate() {
   if (GlobalValueNumbering::Skip(cu_)) {
+    DisableGVNDependentOptimizations(cu_);
     return false;
   }
 
@@ -1407,7 +1412,7 @@ void MIRGraph::ApplyGlobalValueNumberingEnd() {
     cu_->disable_opt |= (1u << kLocalValueNumbering);
   } else {
     LOG(WARNING) << "GVN failed for " << PrettyMethod(cu_->method_idx, *cu_->dex_file);
-    cu_->disable_opt |= (1u << kGvnDeadCodeElimination);
+    DisableGVNDependentOptimizations(cu_);
   }
 }