s390: exploit new mul in TF

src/compiler/s390/instruction-selector-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.
 
 #include "src/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 #include "src/s390/frames-s390.h"
 
@@ skipping 1341 matching lines @@
 
 static inline bool TryMatchInt32SubWithOverflow(InstructionSelector* selector,
                                                 Node* node) {
   return TryMatchInt32OpWithOverflow<kS390_Sub32>(selector, node,
                                                   SubOperandMode);
 }
 
 static inline bool TryMatchInt32MulWithOverflow(InstructionSelector* selector,
                                                 Node* node) {
   if (Node* ovf = NodeProperties::FindProjection(node, 1)) {
-    FlagsContinuation cont = FlagsContinuation::ForSet(kNotEqual, ovf);
-    VisitWord32BinOp(selector, node, kS390_Mul32WithOverflow,
-                     OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps,
-                     &cont);
+    if (CpuFeatures::IsSupported(MISC_INSTR_EXT2)) {
+      DCHECK(TryMatchInt32OpWithOverflow<kS390_Mul32>(
+                 selector, node,
+                 OperandMode::kAllowRRR | OperandMode::kAllowRM) == true);
+    } else {
+      FlagsContinuation cont = FlagsContinuation::ForSet(kNotEqual, ovf);
+      VisitWord32BinOp(selector, node, kS390_Mul32WithOverflow,
+                       OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps,
+                       &cont);
+    }
     return true;
   }
   return TryMatchShiftFromMul<Int32BinopMatcher, kS390_ShiftLeft32>(selector,
                                                                     node);
 }
 
 #if V8_TARGET_ARCH_S390X
 template <ArchOpcode opcode>
 static inline bool TryMatchInt64OpWithOverflow(InstructionSelector* selector,
                                                Node* node, OperandModes mode) {
@@ skipping 1103 matching lines @@
 // static
 MachineOperatorBuilder::AlignmentRequirements
 InstructionSelector::AlignmentRequirements() {
   return MachineOperatorBuilder::AlignmentRequirements::
       FullUnalignedAccessSupport();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8