ART: Enable basic optimizations for try/catch

Generating code for try/catch methods requires having run at least the
instruction simplifier to remove redundant suspend checks. This patch
enables the first group of optimizations when try/catch is present.

Enabled optimizations:
1) IntrinsicsRecognizer
Does not modify the graph, only sets HInvoke::intrinsic_.

2) ConstantFolding
Does not deal with throwing instructions.

3) InstructionSimplifier
May remove a throwing instruction (e.g. LoadClass in VisitCheckCast),
or may turn a throwing instruction into a non-throwing one (ArraySet).
Their corresponding catch phi inputs are not removed but correctness
is preserved.

4) ReferenceTypePropagation
Does not modify the graph, only sets type properties. Typing of
LoadException from catch handler information was added.

5) DeadCodeElimination
Removing individual instructions is fine (same as 3). Removal of dead
blocks was disabled for try/catch.

Change-Id: I2722c3229eb8aaf326391e07f522dbf5186774b8

1 files changed, 5 insertions, 0 deletions

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index c4f64b4ebe..c8b22a838e 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -350,6 +350,9 @@ class HGraph : public ArenaObject<kArenaAllocMisc> {
     return instruction_set_;
   }
 
+  // TODO: Remove once the full compilation pipeline is enabled for try/catch.
+  bool HasTryCatch() const;
+
  private:
   void VisitBlockForDominatorTree(HBasicBlock* block,
                                   HBasicBlock* predecessor,
@@ -4471,6 +4474,8 @@ class HLoadException : public HExpression<0> {
  public:
   HLoadException() : HExpression(Primitive::kPrimNot, SideEffects::None()) {}
 
+  bool CanBeNull() const OVERRIDE { return false; }
+
   DECLARE_INSTRUCTION(LoadException);
 
  private: