MIPS64: ART Vectorizer

MIPS64 implementation which uses MSA extension. Also extended all
relevant checker tests to test MIPS64 implementation.

Test: booted MIPS64R6 in QEMU
Test: ./testrunner.py --target --optimizing -j1 in QEMU

Change-Id: I8b8a2f601076bca1925e21213db8ed1d41d79b52
diff --git a/compiler/optimizing/code_generator_mips64.cc b/compiler/optimizing/code_generator_mips64.cc
index 0961391..68187ca 100644
--- a/compiler/optimizing/code_generator_mips64.cc
+++ b/compiler/optimizing/code_generator_mips64.cc
@@ -951,7 +951,7 @@
       location_builder_(graph, this),
       instruction_visitor_(graph, this),
       move_resolver_(graph->GetArena(), this),
-      assembler_(graph->GetArena()),
+      assembler_(graph->GetArena(), &isa_features),
       isa_features_(isa_features),
       uint32_literals_(std::less<uint32_t>(),
                        graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),