MIPS32R2: Share address computation

For array accesses the element address has the following structure:
Address = CONST_OFFSET + base_addr + index << ELEM_SHIFT

The address part (index << ELEM_SHIFT) can be shared across array
accesses with the same data type and index.

For example, in the following loop 5 accesses can share address
computation:

void foo(int[] a, int[] b, int[] c) {
  for (i...) {
    a[i] = a[i] + 5;
    b[i] = b[i] + c[i];
  }
}

Test: test-art-host, test-art-target
Change-Id: Id09fa782934aad4ee47669275e7e1a4d7d23b0fa
diff --git a/compiler/Android.bp b/compiler/Android.bp
index 3044890..59ca4c7 100644
--- a/compiler/Android.bp
+++ b/compiler/Android.bp
@@ -135,6 +135,7 @@
                 "linker/mips/relative_patcher_mips.cc",
                 "optimizing/code_generator_mips.cc",
                 "optimizing/code_generator_vector_mips.cc",
+                "optimizing/instruction_simplifier_mips.cc",
                 "optimizing/intrinsics_mips.cc",
                 "optimizing/pc_relative_fixups_mips.cc",
                 "utils/mips/assembler_mips.cc",