diff --git a/src/cmd/compile/internal/ssa/expand_calls.go b/src/cmd/compile/internal/ssa/expand_calls.go
index 39d0b61..2852753 100644
--- a/src/cmd/compile/internal/ssa/expand_calls.go
+++ b/src/cmd/compile/internal/ssa/expand_calls.go
@@ -1714,6 +1714,21 @@
 	} else {
 		w = baseArg.Block.NewValue0IA(pos, op, t, auxInt, aux)
 	}
+	// If we are creating an OpArgIntReg/OpArgFloatReg that
+	// corresponds to an in-param that fits entirely in a register,
+	// then enter it into the name/value table. The LocalSlot
+	// is somewhat fictitious, since there is no incoming live
+	// memory version of the parameter, but we need an entry in
+	// NamedValues in order for ssa debug tracking to include
+	// the value in the tracking analysis.
+	if len(pa.Registers) == 1 {
+		loc := LocalSlot{N: aux.Name, Type: t, Off: 0}
+		values, ok := x.f.NamedValues[loc]
+		if !ok {
+			x.f.Names = append(x.f.Names, loc)
+		}
+		x.f.NamedValues[loc] = append(values, w)
+	}
 	x.commonArgs[key] = w
 	if toReplace != nil {
 		toReplace.copyOf(w)