Merge TRUNCDIV and MOD into TRUNCDIV_MOD single operation.

runtime/vm/intermediate_language_arm.cc

Index: runtime/vm/intermediate_language_arm.cc
===================================================================
--- runtime/vm/intermediate_language_arm.cc	(revision 30236)
+++ runtime/vm/intermediate_language_arm.cc	(working copy)
@@ -2266,6 +2266,16 @@
     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::RequiresFpuRegister());
+    summary->AddTemp(Location::RequiresRegister());  // result_div.
+    summary->AddTemp(Location::RequiresRegister());  // result_mod.
+    summary->set_out(Location::RequiresRegister());
+    return summary;
+  }
   if (op_kind() == Token::kMOD) {
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::RequiresRegister());
@@ -2534,6 +2544,57 @@
       __ Bind(&done);
       break;
     }
+    case Token::kTRUNCDIVMOD: {
+      // Handle divide by zero in runtime.
+      __ cmp(right, ShifterOperand(0));
+      __ b(deopt, EQ);
+      Register temp = locs()->temp(0).reg();
+      DRegister dtemp = EvenDRegisterOf(locs()->temp(1).fpu_reg());
+      Register result_div = locs()->temp(2).reg();
+      Register result_mod = locs()->temp(3).reg();
+      __ Asr(temp, left, kSmiTagSize);  // SmiUntag left into temp.
+      __ Asr(IP, right, kSmiTagSize);  // SmiUntag right into IP.
+
+      __ IntegerDivide(result_div, temp, IP, dtemp, DTMP);
+
+      // Check the corner case of dividing the 'MIN_SMI' with -1, in which
+      // case we cannot tag the result.
+      __ CompareImmediate(result_div, 0x40000000);
+      __ b(deopt, EQ);
+      __ Asr(IP, right, kSmiTagSize);  // SmiUntag right into IP.
+      // result_mod <- left - right * result_div.
+      __ mls(result_mod, IP, result_div, temp);
+      __ SmiTag(result_div);
+      __ SmiTag(result_mod);
+      // Correct MOD result:
+      //  res = left % right;
+      //  if (res < 0) {
+      //    if (right < 0) {
+      //      res = res - right;
+      //    } else {
+      //      res = res + right;
+      //    }
+      //  }
+      Label done;
+      __ cmp(result_mod, ShifterOperand(0));
+      __ b(&done, GE);
+      // Result is negative, adjust it.
+      __ cmp(right, ShifterOperand(0));
+      __ sub(result_mod, result_mod, ShifterOperand(right), LT);
+      __ add(result_mod, result_mod, ShifterOperand(right), GE);
+      __ Bind(&done);
+
+      __ 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.
+      __ mov(temp, ShifterOperand(0 +
+          FlowGraphCompiler::DataOffsetFor(kArrayCid) - kHeapObjectTag));
+      Address store_address(result, temp, LSL, 0);
+      __ StoreIntoObjectNoBarrier(result, store_address, result_div);
+      __ add(temp, temp, ShifterOperand(kWordSize));
+      __ StoreIntoObjectNoBarrier(result, store_address, result_mod);
+      break;
+    }
     case Token::kSHR: {
       if (CanDeoptimize()) {
         __ CompareImmediate(right, 0);