Fix an undetected Smi overflow on ARM.

runtime/vm/intermediate_language_arm.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_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/cpu.h"
@@ skipping 2941 matching lines @@
   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());
-    int32_t imm = reinterpret_cast<int32_t>(constant.raw());
+    const int32_t imm = reinterpret_cast<int32_t>(constant.raw());
     switch (op_kind()) {
-      case Token::kSUB: {
-        imm = -imm;  // TODO(regis): What if deopt != NULL && imm == 0x80000000?
-        // Fall through.
-      }
       case Token::kADD: {
         if (deopt == NULL) {
           __ AddImmediate(result, left, imm);
         } else {
           __ AddImmediateSetFlags(result, left, imm);
           __ b(deopt, VS);
         }
         break;
       }
+      case Token::kSUB: {
+        if (deopt == NULL) {
+          __ AddImmediate(result, left, -imm);
+        } else {
+          // Negating imm and using AddImmediateSetFlags would not detect the
+          // overflow when imm == kMinInt32.
+          __ SubImmediateSetFlags(result, left, imm);
+          __ b(deopt, VS);
+        }
+        break;
+      }
       case Token::kMUL: {
         // Keep left value tagged and untag right value.
         const intptr_t value = Smi::Cast(constant).Value();
         if (deopt == NULL) {
           if (value == 2) {
             __ mov(result, ShifterOperand(left, LSL, 1));
           } else {
             __ LoadImmediate(IP, value);
             __ mul(result, left, IP);
           }
@@ skipping 50 matching lines @@
           __ rsb(result, result, ShifterOperand(0));
         }
         __ SmiTag(result);
         break;
       }
       case Token::kBIT_AND: {
         // No overflow check.
         ShifterOperand shifter_op;
         if (ShifterOperand::CanHold(imm, &shifter_op)) {
           __ and_(result, left, shifter_op);
+        } else if (ShifterOperand::CanHold(~imm, &shifter_op)) {
+          __ bic(result, left, shifter_op);
         } else {
-          // TODO(regis): Try to use bic.
           __ LoadImmediate(IP, imm);
           __ and_(result, left, ShifterOperand(IP));
         }
         break;
       }
       case Token::kBIT_OR: {
         // No overflow check.
         ShifterOperand shifter_op;
         if (ShifterOperand::CanHold(imm, &shifter_op)) {
           __ orr(result, left, shifter_op);
         } else {
-          // TODO(regis): Try to use orn.
           __ LoadImmediate(IP, imm);
           __ orr(result, left, ShifterOperand(IP));
         }
         break;
       }
       case Token::kBIT_XOR: {
         // No overflow check.
         ShifterOperand shifter_op;
         if (ShifterOperand::CanHold(imm, &shifter_op)) {
           __ eor(result, left, shifter_op);
@@ skipping 3092 matching lines @@
   compiler->GenerateCall(token_pos(),
                          &label,
                          PcDescriptors::kOther,
                          locs());
   __ Drop(ArgumentCount());  // Discard arguments.
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM