Adds support for ARMv6.

runtime/vm/instructions_arm_test.cc

Index: runtime/vm/instructions_arm_test.cc
===================================================================
--- runtime/vm/instructions_arm_test.cc	(revision 33437)
+++ runtime/vm/instructions_arm_test.cc	(working copy)
@@ -6,6 +6,7 @@
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
+#include "vm/cpu.h"
 #include "vm/instructions.h"
 #include "vm/stub_code.h"
 #include "vm/unit_test.h"
@@ -62,6 +63,45 @@
             jump2.TargetAddress());
 }
 
+
+#if defined(USING_SIMULATOR)
+ASSEMBLER_TEST_GENERATE(JumpARMv6, assembler) {
+  // ARMv7 is the default.
+  HostCPUFeatures::set_arm_version(ARMv6);
+  __ BranchPatchable(&StubCode::InstanceFunctionLookupLabel());
+  __ BranchPatchable(&StubCode::AllocateArrayLabel());
+  HostCPUFeatures::set_arm_version(ARMv7);
+}
+
+
+ASSEMBLER_TEST_RUN(JumpARMv6, test) {
+  HostCPUFeatures::set_arm_version(ARMv6);
+  const Code& code = test->code();
+  const Instructions& instrs = Instructions::Handle(code.instructions());
+  bool status =
+      VirtualMemory::Protect(reinterpret_cast<void*>(instrs.EntryPoint()),
+                             instrs.size(),
+                             VirtualMemory::kReadWrite);
+  EXPECT(status);
+  JumpPattern jump1(test->entry(), test->code());
+  EXPECT_EQ(StubCode::InstanceFunctionLookupLabel().address(),
+            jump1.TargetAddress());
+  JumpPattern jump2(test->entry() + jump1.pattern_length_in_bytes(),
+                    test->code());
+  EXPECT_EQ(StubCode::AllocateArrayLabel().address(),
+            jump2.TargetAddress());
+  uword target1 = jump1.TargetAddress();
+  uword target2 = jump2.TargetAddress();
+  jump1.SetTargetAddress(target2);
+  jump2.SetTargetAddress(target1);
+  EXPECT_EQ(StubCode::AllocateArrayLabel().address(),
+            jump1.TargetAddress());
+  EXPECT_EQ(StubCode::InstanceFunctionLookupLabel().address(),
+            jump2.TargetAddress());
+  HostCPUFeatures::set_arm_version(ARMv7);
+}
+#endif
+
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM