[dev.ssa] cmd/compile: implement ONOT

Co-hacking with josharian at Gophercon.

Change-Id: Ia59dfab676c6ed598c2c25483439cd1395a4ea87
Reviewed-on: https://go-review.googlesource.com/12029
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/cmd/compile/internal/ssa/gen/genericOps.go b/src/cmd/compile/internal/ssa/gen/genericOps.go
index c410cc4..9155e00 100644
--- a/src/cmd/compile/internal/ssa/gen/genericOps.go
+++ b/src/cmd/compile/internal/ssa/gen/genericOps.go
@@ -22,6 +22,9 @@
 	{name: "Greater"}, // arg0 > arg1
 	{name: "Geq"},     // arg0 <= arg1
 
+	// 1-input ops
+	{name: "Not"}, // !arg0
+
 	// Data movement
 	{name: "Phi"},  // select an argument based on which predecessor block we came from
 	{name: "Copy"}, // output = arg0