Eliminate overflow check for non-overflowing smi << operations.

runtime/vm/intermediate_language_mips.cc

 // Copyright (c) 2013, 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_MIPS.
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 2543 matching lines @@
   }
   if (compiler->ForceSlowPathForStackOverflow()) {
     __ b(slow_path->entry_label());
   }
   __ Bind(slow_path->exit_label());
 }
 
 
 static void EmitSmiShiftLeft(FlowGraphCompiler* compiler,
                              BinarySmiOpInstr* shift_left) {
-  const bool is_truncating = shift_left->is_truncating();
+  const bool is_truncating = shift_left->IsTruncating();
   const LocationSummary& locs = *shift_left->locs();
   Register left = locs.in(0).reg();
   Register result = locs.out(0).reg();
   Label* deopt = shift_left->CanDeoptimize() ?
       compiler->AddDeoptStub(shift_left->deopt_id(), ICData::kDeoptBinarySmiOp)
       : NULL;
 
   __ TraceSimMsg("EmitSmiShiftLeft");
 
   if (locs.in(1).IsConstant()) {
@@ skipping 99 matching lines @@
 }
 
 
 LocationSummary* BinarySmiOpInstr::MakeLocationSummary(Isolate* isolate,
                                                        bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps =
       ((op_kind() == Token::kADD) ||
        (op_kind() == Token::kMOD) ||
        (op_kind() == Token::kTRUNCDIV) ||
-       (((op_kind() == Token::kSHL) && !is_truncating()) ||
+       (((op_kind() == Token::kSHL) && !IsTruncating()) ||
          (op_kind() == Token::kSHR))) ? 1 : 0;
   LocationSummary* summary = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   if (op_kind() == Token::kTRUNCDIV) {
     summary->set_in(0, Location::RequiresRegister());
     if (RightIsPowerOfTwoConstant()) {
       ConstantInstr* right_constant = right()->definition()->AsConstant();
       summary->set_in(1, Location::Constant(right_constant->value()));
     } else {
       summary->set_in(1, Location::RequiresRegister());
     }
     summary->set_temp(0, Location::RequiresRegister());
     summary->set_out(0, Location::RequiresRegister());
     return summary;
   }
   if (op_kind() == Token::kMOD) {
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::RequiresRegister());
     summary->set_temp(0, Location::RequiresRegister());
     summary->set_out(0, Location::RequiresRegister());
     return summary;
   }
   summary->set_in(0, Location::RequiresRegister());
   summary->set_in(1, Location::RegisterOrSmiConstant(right()));
-  if (((op_kind() == Token::kSHL) && !is_truncating()) ||
+  if (((op_kind() == Token::kSHL) && !IsTruncating()) ||
       (op_kind() == Token::kSHR)) {
     summary->set_temp(0, Location::RequiresRegister());
   } else if (op_kind() == Token::kADD) {
     // Need an extra temp for the overflow detection code.
     summary->set_temp(0, Location::RequiresRegister());
   }
   // We make use of 3-operand instructions by not requiring result register
   // to be identical to first input register as on Intel.
   summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void BinarySmiOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   __ TraceSimMsg("BinarySmiOpInstr");
   if (op_kind() == Token::kSHL) {
     EmitSmiShiftLeft(compiler, this);
     return;
   }
 
-  ASSERT(!is_truncating());
   Register left = locs()->in(0).reg();
   Register result = locs()->out(0).reg();
   Label* deopt = NULL;
   if (CanDeoptimize()) {
     deopt = compiler->AddDeoptStub(deopt_id(), ICData::kDeoptBinarySmiOp);
   }
 
   if (locs()->in(1).IsConstant()) {
     const Object& constant = locs()->in(1).constant();
     ASSERT(constant.IsSmi());
@@ skipping 1951 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(S4, kInvalidObjectPointer);
   __ LoadImmediate(S5, kInvalidObjectPointer);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS