Avoid generating jmp +0.

When a block branches to a non-following block, but blocks
in-between do branch to it, we can avoid doing the branch.

Change-Id: I9b343f662a4efc718cd4b58168f93162a24e1219

1 files changed, 10 insertions, 0 deletions

diff --git a/compiler/optimizing/code_generator.h b/compiler/optimizing/code_generator.h
index efd0c84..6c78f10 100644
--- a/compiler/optimizing/code_generator.h
+++ b/compiler/optimizing/code_generator.h
@@ -91,6 +91,8 @@ class CodeGenerator {
 
   HGraph* GetGraph() const { return graph_; }
 
+  HBasicBlock* GetNextBlockToEmit() const;
+  HBasicBlock* FirstNonEmptyBlock(HBasicBlock* block) const;
   bool GoesToNextBlock(HBasicBlock* current, HBasicBlock* next) const;
 
   size_t GetStackSlotOfParameter(HParameterValue* parameter) const {
@@ -314,6 +316,14 @@ class CodeGenerator {
     return GetFrameSize() == (CallPushesPC() ? GetWordSize() : 0);
   }
 
+  // Arm64 has its own type for a label, so we need to templatize this method
+  // to share the logic.
+  template <typename T>
+  T* CommonGetLabelOf(T* raw_pointer_to_labels_array, HBasicBlock* block) const {
+    block = FirstNonEmptyBlock(block);
+    return raw_pointer_to_labels_array + block->GetBlockId();
+  }
+
   // Frame size required for this method.
   uint32_t frame_size_;
   uint32_t core_spill_mask_;