[turbofan] introduce Int32/64AbsWithOverflow optional operator

src/compiler/s390/instruction-selector-s390.cc

Index: src/compiler/s390/instruction-selector-s390.cc
diff --git a/src/compiler/s390/instruction-selector-s390.cc b/src/compiler/s390/instruction-selector-s390.cc
index 4b70e41ffdab884eb5ee8aae7fe74652c4cc9a54..3ead655b7b076b9a59be69783fbbb2b5eaa5b290 100644
--- a/src/compiler/s390/instruction-selector-s390.cc
+++ b/src/compiler/s390/instruction-selector-s390.cc
@@ -389,6 +389,11 @@ bool ProduceWord32Result(Node* node) {
       switch (load_rep.representation()) {
         case MachineRepresentation::kWord32:
           return true;
+        case MachineRepresentation::kWord8:
+          if (load_rep.IsSigned())
+            return false;
+          else
+            return true;
         default:
           return false;
       }
@@ -1242,6 +1247,14 @@ void InstructionSelector::VisitWord32ReverseBits(Node* node) { UNREACHABLE(); }
 void InstructionSelector::VisitWord64ReverseBits(Node* node) { UNREACHABLE(); }
 #endif
 
+void InstructionSelector::VisitInt32AbsWithOverflow(Node* node) {
+  UNREACHABLE();

[Benedikt Meurer, 2017/03/31 04:33:08]

Can you also provide a baseline implementation of this.

+}
+
+void InstructionSelector::VisitInt64AbsWithOverflow(Node* node) {
+  UNREACHABLE();

[Benedikt Meurer, 2017/03/31 04:33:08]

Same here.

+}
+
 void InstructionSelector::VisitWord64ReverseBytes(Node* node) {
   S390OperandGenerator g(this);
   Emit(kS390_LoadReverse64RR, g.DefineAsRegister(node),
@@ -2037,7 +2050,15 @@ void VisitWordCompareZero(InstructionSelector* selector, Node* user,
                     selector, node, kS390_Mul32WithOverflow,
                     OperandMode::kInt32Imm | OperandMode::kAllowDistinctOps,
                     cont);
+              case IrOpcode::kInt32AbsWithOverflow:
+                cont->OverwriteAndNegateIfEqual(kOverflow);
+                return VisitWord32UnaryOp(selector, node, kS390_Abs32,
+                                          OperandMode::kNone, cont);
 #if V8_TARGET_ARCH_S390X
+              case IrOpcode::kInt64AbsWithOverflow:
+                cont->OverwriteAndNegateIfEqual(kOverflow);
+                return VisitWord64UnaryOp(selector, node, kS390_Abs64,
+                                          OperandMode::kNone, cont);
               case IrOpcode::kInt64AddWithOverflow:
                 cont->OverwriteAndNegateIfEqual(kOverflow);
                 return VisitWord64BinOp(selector, node, kS390_Add64,
@@ -2450,6 +2471,8 @@ InstructionSelector::SupportedMachineOperatorFlags() {
          MachineOperatorBuilder::kWord32Popcnt |
          MachineOperatorBuilder::kWord32ReverseBytes |
          MachineOperatorBuilder::kWord64ReverseBytes |
+         MachineOperatorBuilder::kInt32AbsWithOverflow |
+         MachineOperatorBuilder::kInt64AbsWithOverflow |
          MachineOperatorBuilder::kWord64Popcnt;
 }