s390: use new mul instruction

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 1564 matching lines @@
       break;
     }
     case Token::SUB: {
       __ SubP(scratch1, left, right);
       __ b(overflow, &stub_call);
       __ LoadRR(right, scratch1);
       break;
     }
     case Token::MUL: {
       Label mul_zero;
+      if (CpuFeatures::IsSupported(MISC_INSTR_EXT2)) {
+        __ SmiUntag(ip, right);
+        __ MulPWithCondition(scratch2, ip, left);
+        __ b(overflow, &stub_call);
+        __ beq(&mul_zero, Label::kNear);
+        __ LoadRR(right, scratch2);
+      } else {
 #if V8_TARGET_ARCH_S390X
-      // Remove tag from both operands.
-      __ SmiUntag(ip, right);
-      __ SmiUntag(scratch2, left);
-      __ mr_z(scratch1, ip);
-      // Check for overflowing the smi range - no overflow if higher 33 bits of
-      // the result are identical.
-      __ lr(ip, scratch2);  // 32 bit load
-      __ sra(ip, Operand(31));
-      __ cr_z(ip, scratch1);  // 32 bit compare
-      __ bne(&stub_call);
+        // Remove tag from both operands.
+        __ SmiUntag(ip, right);
+        __ SmiUntag(scratch2, left);
+        __ mr_z(scratch1, ip);
+        // Check for overflowing the smi range - no overflow if higher 33 bits
+        // of the result are identical.
+        __ 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);
-      __ bne(&stub_call);
+        __ 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);
+        __ bne(&stub_call);
 #endif
-      // Go slow on zero result to handle -0.
-      __ chi(scratch2, Operand::Zero());
-      __ beq(&mul_zero, Label::kNear);
+        // 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);
+        __ SmiTag(right, scratch2);
 #else
-      __ LoadRR(right, scratch2);
+        __ LoadRR(right, scratch2);
 #endif
+      }
       __ b(&done);
       // We need -0 if we were multiplying a negative number with 0 to get 0.
       // We know one of them was zero.
       __ bind(&mul_zero);
       __ AddP(scratch2, right, left);
       __ CmpP(scratch2, Operand::Zero());
       __ blt(&stub_call);
       __ LoadSmiLiteral(right, Smi::kZero);
       break;
     }
@@ skipping 1163 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