s390: improve floating point and integer convertion

src/full-codegen/s390/full-codegen-s390.cc

 // Copyright 2015 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.
 
 #if V8_TARGET_ARCH_S390
 
 #include "src/ast/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-factory.h"
@@ skipping 1579 matching lines @@
         __ lr(ip, scratch2);  // 32 bit load
         __ sra(ip, Operand(31));
         __ cr_z(ip, scratch1);  // 32 bit compare
         __ bne(&stub_call);
 #else
         __ SmiUntag(ip, right);
         __ LoadRR(scratch2, left);  // load into low order of reg pair
         __ mr_z(scratch1, ip);      // R4:R5 = R5 * ip
         // Check for overflowing the smi range - no overflow if higher 33 bits
         // of the result are identical.
-        __ TestIfInt32(scratch1, scratch2, ip);
+        __ lr(ip, scratch2);  // 32 bit load
+        __ sra(ip, Operand(31));
+        __ cr_z(ip, scratch1);  // 32 bit compare
         __ bne(&stub_call);
 #endif
         // Go slow on zero result to handle -0.
         __ chi(scratch2, Operand::Zero());
         __ beq(&mul_zero, Label::kNear);
 #if V8_TARGET_ARCH_S390X
         __ SmiTag(right, scratch2);
 #else
         __ LoadRR(right, scratch2);
 #endif
@@ skipping 1113 matching lines @@
   USE(kOSRBranchInstruction);
   DCHECK(kOSRBranchInstruction == br_instr);
 
   DCHECK(interrupt_address ==
          isolate->builtins()->OnStackReplacement()->entry());
   return ON_STACK_REPLACEMENT;
 }
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_S390