MIPS: Optimize code generation of check-cast and instance-of.

This is in preparation for read barrier support.

Test: test-art-host-gtest
Test: booted MIPS32R2 in QEMU
Test: test-art-target
Test: booted MIPS64 (with 2nd arch MIPS32R2) in QEMU
Test: test-art-target (MIPS64R6 only)

Note: built with ART_HEAP_POISONING=true.

Change-Id: I072ad41944a5ef390c81458c0ba49a71684cb2a9
2 files changed