[optimizing] Add basic PackedSwitch support

Add HPackedSwitch, and generate it from the builder.  Code generators
convert this to a series of compare/branch tests.  Better implementation
in the code generators as a real jump table will follow as separate CLs.

Change-Id: If14736fa4d62809b6ae95280148c55682e856911
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/compiler/optimizing/graph_checker.cc b/compiler/optimizing/graph_checker.cc
index 583da30438..4e1cafee66 100644
--- a/compiler/optimizing/graph_checker.cc
+++ b/compiler/optimizing/graph_checker.cc
@@ -743,6 +743,22 @@ void SSAChecker::HandleBooleanInput(HInstruction* instruction, size_t input_inde
   }
 }
 
+void SSAChecker::VisitPackedSwitch(HPackedSwitch* instruction) {
+  VisitInstruction(instruction);
+  // Check that the number of block successors matches the switch count plus
+  // one for the default block.
+  HBasicBlock* block = instruction->GetBlock();
+  if (instruction->GetNumEntries() + 1u != block->GetSuccessors().size()) {
+    AddError(StringPrintf(
+        "%s instruction %d in block %d expects %u successors to the block, but found: %zu.",
+        instruction->DebugName(),
+        instruction->GetId(),
+        block->GetBlockId(),
+        instruction->GetNumEntries() + 1u,
+        block->GetSuccessors().size()));
+  }
+}
+
 void SSAChecker::VisitIf(HIf* instruction) {
   VisitInstruction(instruction);
   HandleBooleanInput(instruction, 0);