S390: Implemented SLBR in s390 simulator.

src/s390/simulator-s390.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdarg.h>
 #include <stdlib.h>
 #include <cmath>
 
 #if V8_TARGET_ARCH_S390
 
@@ skipping 3021 matching lines @@
       if (TestConditionCode((Condition)2) || TestConditionCode((Condition)3)) {
         alu_out = alu_out + 1;
         isOF = isOF_original || CheckOverflowForUIntAdd(alu_out, 1);
       } else {
         isOF = isOF_original;
       }
       set_low_register(r1, alu_out);
       SetS390ConditionCodeCarry<uint32_t>(alu_out, isOF);
       break;
     }
+    case SLBR: {
+      RREInstruction* rrinst = reinterpret_cast<RREInstruction*>(instr);
+      int r1 = rrinst->R1Value();
+      int r2 = rrinst->R2Value();
+      uint32_t r1_val = get_low_register<uint32_t>(r1);
+      uint32_t r2_val = get_low_register<uint32_t>(r2);
+      uint32_t alu_out = 0;
+      bool isOF = false;
+
+      alu_out = r1_val - r2_val;
+      bool isOF_original = CheckOverflowForUIntSub(r1_val, r2_val);
+      if (TestConditionCode((Condition)2) || TestConditionCode((Condition)3)) {
+        alu_out = alu_out - 1;
+        isOF = isOF_original || CheckOverflowForUIntSub(alu_out, 1);
+      } else {
+        isOF = isOF_original;
+      }
+      set_low_register(r1, alu_out);
+      SetS390ConditionCodeCarry<uint32_t>(alu_out, isOF);
+      break;
+    }
     default: { return DecodeFourByteFloatingPoint(instr); }
   }
   return true;
 }
 
 void Simulator::DecodeFourByteFloatingPointIntConversion(Instruction* instr) {
   Opcode op = instr->S390OpcodeValue();
   switch (op) {
     case CDLFBR:
     case CDLGBR:
@@ skipping 2046 matching lines @@
   uintptr_t address = *stack_slot;
   set_register(sp, current_sp + sizeof(uintptr_t));
   return address;
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // USE_SIMULATOR
 #endif  // V8_TARGET_ARCH_S390