S390: Fix CEBR sim to treat operands as floats

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 3388 matching lines @@
         fr1_val /= fr2_val;
         set_d_register_from_float32(r1, fr1_val);
         SetS390ConditionCode<float>(fr1_val, 0);
       } else if (op == CDBR) {
         if (isNaN(r1_val) || isNaN(r2_val)) {
           condition_reg_ = CC_OF;
         } else {
           SetS390ConditionCode<double>(r1_val, r2_val);
         }
       } else if (op == CEBR) {
-        if (isNaN(r1_val) || isNaN(r2_val)) {
+        if (isNaN(fr1_val) || isNaN(fr2_val)) {
           condition_reg_ = CC_OF;
         } else {
-          SetS390ConditionCode<float>(r1_val, r2_val);
+          SetS390ConditionCode<float>(fr1_val, fr2_val);
         }
       } else if (op == CDGBR) {
         int64_t r2_val = get_register(r2);
         double r1_val = static_cast<double>(r2_val);
         set_d_register_from_double(r1, r1_val);
       } else if (op == CEGBR) {
         int64_t fr2_val = get_register(r2);
         float fr1_val = static_cast<float>(fr2_val);
         set_d_register_from_float32(r1, fr1_val);
       } else if (op == CDFBR) {
@@ skipping 1616 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