Fix excessive deoptimizations in Meteor: kSHL on two Smi-s can easily overflow, which led to deopti…

runtime/vm/intermediate_language_ia32.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 1389 matching lines @@
     return summary;
   } else if (op_kind() == Token::kSHR) {
     const intptr_t kNumTemps = 1;
     LocationSummary* summary = new LocationSummary(kNumInputs, kNumTemps);
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::RegisterLocation(ECX));
     summary->set_out(Location::SameAsFirstInput());
     summary->set_temp(0, Location::RequiresRegister());
     return summary;
   } else if (op_kind() == Token::kSHL) {
+    // Two Smi operands can easily overflow into Mint.
     const intptr_t kNumTemps = 2;
-    LocationSummary* summary = new LocationSummary(kNumInputs, kNumTemps);
-    summary->set_in(0, Location::RequiresRegister());
+    LocationSummary* summary =
+        new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
+    summary->set_in(0, Location::RegisterLocation(EAX));
     summary->set_in(1, Location::RequiresRegister());
     summary->set_out(Location::SameAsFirstInput());
     summary->set_temp(0, Location::RequiresRegister());
     summary->set_temp(1, Location::RegisterLocation(ECX));
     return summary;
   } else {
     const intptr_t kNumTemps = 1;
     LocationSummary* summary = new LocationSummary(kNumInputs, kNumTemps);
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::RequiresRegister());
@@ skipping 89 matching lines @@
       __ j(LESS, &count_ok, Assembler::kNearJump);
       __ movl(right, kCountLimit);
       __ Bind(&count_ok);
       ASSERT(right == ECX);  // Count must be in ECX
       __ SmiUntag(left);
       __ sarl(left, right);
       __ SmiTag(left);
       break;
     }
     case Token::kSHL: {
+      Label call_method, done;
       // Check if count too large for handling it inlined.
       __ cmpl(right,
           Immediate(reinterpret_cast<int64_t>(Smi::New(Smi::kBits))));
-      __ j(ABOVE_EQUAL, deopt);
+      __ j(ABOVE_EQUAL, &call_method, Assembler::kNearJump);
       Register right_temp = comp->locs()->temp(1).reg();
       ASSERT(right_temp == ECX);  // Count must be in ECX
       __ movl(right_temp, right);
       __ SmiUntag(right_temp);
       // Overflow test (preserve temp and right);
       __ shll(left, right_temp);
       __ sarl(left, right_temp);
       __ cmpl(left, temp);
-      __ j(NOT_EQUAL, deopt);  // Overflow.
+      __ j(NOT_EQUAL, &call_method, Assembler::kNearJump);  // Overflow.
       // Shift for result now we know there is no overflow.
       __ shll(left, right_temp);
+      __ jmp(&done);
+      {
+        __ Bind(&call_method);
+        Function& target = Function::ZoneHandle(
+            comp->ic_data()->GetTargetForReceiverClassId(kSmi));
+        ASSERT(!target.IsNull());
+        const intptr_t kArgumentCount = 2;
+        __ pushl(temp);
+        __ pushl(right);
+        compiler->GenerateStaticCall(comp->instance_call()->cid(),
+                                     comp->instance_call()->token_index(),
+                                     comp->instance_call()->try_index(),
+                                     target,
+                                     kArgumentCount,
+                                     Array::Handle());  // No argument names.
+        ASSERT(result == EAX);
+      }
+      __ Bind(&done);
       break;
     }
     case Token::kDIV: {
       // Dispatches to 'Double./'.
       // TODO(srdjan): Implement as conversion to double and double division.
       UNREACHABLE();
       break;
     }
     case Token::kMOD: {
       // TODO(srdjan): Implement.
@@ skipping 187 matching lines @@
   intptr_t test_class_id;
   Function& target = Function::Handle();
   ic_data.GetOneClassCheckAt(0, &test_class_id, &target);
 
   Register value = locs()->in(0).reg();
   Register result = locs()->out().reg();
   ASSERT(value == result);
   Label* deopt = compiler->AddDeoptStub(instance_call()->cid(),
                                         instance_call()->token_index(),
                                         instance_call()->try_index(),
-                                        kDeoptSmiBinaryOp,
+                                        kDeoptUnaryOp,
                                         value);
   if (test_class_id == kSmi) {
     __ testl(value, Immediate(kSmiTagMask));
     __ j(NOT_ZERO, deopt);
     switch (op_kind()) {
       case Token::kNEGATE:
         __ negl(value);
         __ j(OVERFLOW, deopt);
         break;
       case Token::kBIT_NOT:
@@ skipping 32 matching lines @@
   intptr_t test_class_id;
   Function& target = Function::Handle();
   ic_data.GetOneClassCheckAt(0, &test_class_id, &target);
 
   Register value = locs()->in(0).reg();
   Register result = locs()->out().reg();
   ASSERT(value == result);
   Label* deopt = compiler->AddDeoptStub(instance_call()->cid(),
                                         instance_call()->token_index(),
                                         instance_call()->try_index(),
-                                        kDeoptSmiBinaryOp,
+                                        kDeoptUnaryOp,
                                         value);
   if (test_class_id == kDouble) {
     Register temp = locs()->temp(0).reg();
     ASSERT(result != temp);
     __ testl(value, Immediate(kSmiTagMask));
     __ j(ZERO, deopt);  // Smi.
     __ CompareClassId(value, kDouble, temp);
     __ j(NOT_EQUAL, deopt);
     // Allocate result object.
     const Class& double_class = compiler->double_class();
@@ skipping 127 matching lines @@
                                  instance_call()->argument_names());
   }
   __ Bind(&done);
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64