Re-enable tests with the optimizing compiler.

Tests run ok on my host/target. I reverted the move to
using thumb2, because tests were crashing. But I could not
reproduce file limits issues.

Change-Id: I26bc4ec1eb6c227750d11210e012d9d3b1d824af
diff --git a/compiler/optimizing/code_generator_arm.h b/compiler/optimizing/code_generator_arm.h
index 0e2a079..712a24c 100644
--- a/compiler/optimizing/code_generator_arm.h
+++ b/compiler/optimizing/code_generator_arm.h
@@ -20,7 +20,7 @@
 #include "code_generator.h"
 #include "nodes.h"
 #include "parallel_move_resolver.h"
-#include "utils/arm/assembler_thumb2.h"
+#include "utils/arm/assembler_arm32.h"
 
 namespace art {
 namespace arm {
@@ -180,7 +180,7 @@
   LocationsBuilderARM location_builder_;
   InstructionCodeGeneratorARM instruction_visitor_;
   ParallelMoveResolverARM move_resolver_;
-  Thumb2Assembler assembler_;
+  Arm32Assembler assembler_;
 
   DISALLOW_COPY_AND_ASSIGN(CodeGeneratorARM);
 };
diff --git a/compiler/optimizing/codegen_test.cc b/compiler/optimizing/codegen_test.cc
index fd534ce..7ec0c84 100644
--- a/compiler/optimizing/codegen_test.cc
+++ b/compiler/optimizing/codegen_test.cc
@@ -52,10 +52,6 @@
   typedef int32_t (*fptr)();
   CommonCompilerTest::MakeExecutable(allocator.GetMemory(), allocator.GetSize());
   fptr f = reinterpret_cast<fptr>(allocator.GetMemory());
-#if defined(__arm__)
-  // For thumb we need the bottom bit set.
-  f = reinterpret_cast<fptr>(reinterpret_cast<uintptr_t>(f) + 1);
-#endif
   int32_t result = f();
   if (has_result) {
     CHECK_EQ(result, expected);
diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 56029aa..ccacbef 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -101,6 +101,10 @@
   }
 
   InstructionSet instruction_set = GetCompilerDriver()->GetInstructionSet();
+  // The optimizing compiler currently does not have a Thumb2 assembler.
+  if (instruction_set == kThumb2) {
+    instruction_set = kArm;
+  }
   CodeGenerator* codegen = CodeGenerator::Create(&arena, graph, instruction_set);
   if (codegen == nullptr) {
     if (shouldCompile) {