MIPS: Lattice-based representation inference, powered by left/right specific type feedback for Bina…

src/mips/simulator-mips.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2201 matching lines @@
         // Instructions using HI and LO registers.
         case MULT:
           set_register(LO, static_cast<int32_t>(i64hilo & 0xffffffff));
           set_register(HI, static_cast<int32_t>(i64hilo >> 32));
           break;
         case MULTU:
           set_register(LO, static_cast<int32_t>(u64hilo & 0xffffffff));
           set_register(HI, static_cast<int32_t>(u64hilo >> 32));
           break;
         case DIV:
-          // Divide by zero was not checked in the configuration step - div and
-          // divu do not raise exceptions. On division by 0, the result will
-          // be UNPREDICTABLE.
-          if (rt != 0) {
+          // Divide by zero and overflow was not checked in the configuration
+          // step - div and divu do not raise exceptions. On division by 0 and
+          // on overflow (INT_MIN/-1), the result will be UNPREDICTABLE.
+          if (rt != 0 && !(rs == INT_MIN && rt == -1)) {
             set_register(LO, rs / rt);
             set_register(HI, rs % rt);
           }
           break;
         case DIVU:
           if (rt_u != 0) {
             set_register(LO, rs_u / rt_u);
             set_register(HI, rs_u % rt_u);
           }
           break;
@@ skipping 601 matching lines @@
 }
 
 
 #undef UNSUPPORTED
 
 } }  // namespace v8::internal
 
 #endif  // USE_SIMULATOR
 
 #endif  // V8_TARGET_ARCH_MIPS