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

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 12185866cd..1e06ea86a2 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -27,6 +27,7 @@
 #endif
 
 #ifdef ART_ENABLE_CODEGEN_mips
+#include "instruction_simplifier_mips.h"
 #include "pc_relative_fixups_mips.h"
 #endif
 
@@ -528,6 +529,8 @@ static HOptimization* BuildOptimization(
 #ifdef ART_ENABLE_CODEGEN_mips
   } else if (opt_name == mips::PcRelativeFixups::kPcRelativeFixupsMipsPassName) {
     return new (arena) mips::PcRelativeFixups(graph, codegen, stats);
+  } else if (opt_name == mips::InstructionSimplifierMips::kInstructionSimplifierMipsPassName) {
+    return new (arena) mips::InstructionSimplifierMips(graph, codegen, stats);
 #endif
 #ifdef ART_ENABLE_CODEGEN_x86
   } else if (opt_name == x86::PcRelativeFixups::kPcRelativeFixupsX86PassName) {
@@ -669,11 +672,14 @@ void OptimizingCompiler::RunArchOptimizations(InstructionSet instruction_set,
 #endif
 #ifdef ART_ENABLE_CODEGEN_mips
     case kMips: {
+      mips::InstructionSimplifierMips* simplifier =
+          new (arena) mips::InstructionSimplifierMips(graph, codegen, stats);
       SideEffectsAnalysis* side_effects = new (arena) SideEffectsAnalysis(graph);
       GVNOptimization* gvn = new (arena) GVNOptimization(graph, *side_effects, "GVN$after_arch");
       mips::PcRelativeFixups* pc_relative_fixups =
           new (arena) mips::PcRelativeFixups(graph, codegen, stats);
       HOptimization* mips_optimizations[] = {
+          simplifier,
           side_effects,
           gvn,
           pc_relative_fixups,