Merge TRUNCDIV and MOD into TRUNCDIV_MOD single operation.

runtime/vm/intermediate_language_mips.cc

Index: runtime/vm/intermediate_language_mips.cc
===================================================================
--- runtime/vm/intermediate_language_mips.cc	(revision 30236)
+++ runtime/vm/intermediate_language_mips.cc	(working copy)
@@ -2393,6 +2393,15 @@
     summary->set_out(Location::RequiresRegister());
     return summary;
   }
+  if (op_kind() == Token::kTRUNCDIVMOD) {
+    summary->set_in(0, Location::RequiresRegister());
+    summary->set_in(1, Location::RequiresRegister());
+    summary->AddTemp(Location::RequiresRegister());
+    summary->AddTemp(Location::RequiresRegister());  // result_div.
+    summary->AddTemp(Location::RequiresRegister());  // result_mod.
+    summary->set_out(Location::RequiresRegister());
+    return summary;
+  }
   summary->set_in(0, Location::RequiresRegister());
   summary->set_in(1, Location::RegisterOrSmiConstant(right()));
   if (((op_kind() == Token::kSHL) && !is_truncating()) ||
@@ -2660,6 +2669,51 @@
       __ SmiTag(result);
       break;
     }
+    case Token::kTRUNCDIVMOD: {
+      Register temp = locs()->temp(0).reg();
+      Register result_div = locs()->temp(1).reg();
+      Register result_mod = locs()->temp(2).reg();
+      // Handle divide by zero in runtime.
+      __ beq(right, ZR, deopt);
+      __ sra(temp, left, kSmiTagSize);  // SmiUntag left into temp.
+      __ sra(TMP, right, kSmiTagSize);  // SmiUntag right into TMP.
+      __ div(temp, TMP);
+      __ mflo(result_div);
+      __ mfhi(result_mod);
+      // Check the corner case of dividing the 'MIN_SMI' with -1, in which
+      // case we cannot tag the result.
+      __ BranchEqual(result_div, 0x40000000, deopt);
+      //  res = left % right;
+      //  if (res < 0) {
+      //    if (right < 0) {
+      //      res = res - right;
+      //    } else {
+      //      res = res + right;
+      //    }
+      //  }
+      Label done, subtract;
+      __ bgez(result_mod, &done);
+      __ bltz(right, &subtract);
+      __ addu(result_mod, result_mod, TMP);
+      __ b(&done);
+      __ Bind(&subtract);
+      __ subu(result_mod, result_mod, TMP);
+      __ Bind(&done);
+
+      __ SmiTag(result_div);
+      __ SmiTag(result_mod);
+      __ LoadObject(result, Array::ZoneHandle(Array::New(2, Heap::kOld)));
+      // Note that index is expected smi-tagged, (i.e, times 2) for all arrays.
+      // [0]: divide resut, [1]: mod result.
+      __ LoadImmediate(temp,
+          FlowGraphCompiler::DataOffsetFor(kArrayCid) - kHeapObjectTag);
+      __ addu(temp, result, temp);
+      Address div_result_address(temp, 0);
+      Address mod_result_address(temp, kWordSize);
+      __ StoreIntoObjectNoBarrier(result, div_result_address, result_div);
+      __ StoreIntoObjectNoBarrier(result, mod_result_address, result_mod);
+      break;
+    }
     case Token::kSHR: {
       Register temp = locs()->temp(0).reg();
       if (CanDeoptimize()) {