[turbofan] Introduce a dedicated CheckBounds operator.

src/compiler/simplified-lowering.cc

Index: src/compiler/simplified-lowering.cc
diff --git a/src/compiler/simplified-lowering.cc b/src/compiler/simplified-lowering.cc
index 98b5a83068b6bfae56ede79bee3c174794140329..628745c711df5707f1cb86eb4070417e559af620 100644
--- a/src/compiler/simplified-lowering.cc
+++ b/src/compiler/simplified-lowering.cc
@@ -1533,6 +1533,13 @@ class RepresentationSelector {
         }
         return;
       }
+
+      case IrOpcode::kCheckBounds: {
+        VisitBinop(node, UseInfo::CheckedSigned32AsWord32(),
+                   UseInfo::TruncatingWord32(), MachineRepresentation::kWord32);
+        return;
+      }
+
       case IrOpcode::kAllocate: {
         ProcessInput(node, 0, UseInfo::TruncatingWord32());
         ProcessRemainingInputs(node, 1);