test/codegen: add float max/min codegen test

As CL 514596 and CL 514775 adds hardware implement of float
max/min, we should add codegen test for these two CL.

Change-Id: I347331032fe9f67a2e6fdb5d3cfe20203296b81c
Reviewed-on: https://go-review.googlesource.com/c/go/+/561295
Reviewed-by: Joel Sing <joel@sing.id.au>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: M Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: David Chase <drchase@google.com>

test/codegen/floats.go

@@ -156,3 +156,35 @@ func ArrayCopy(a [16]byte) (b [16]byte) {
 	b = a
 	return
 }
+
+// ---------------- //
+//  Float Min/Max   //
+// ---------------- //
+
+func Float64Min(a, b float64) float64 {
+	// amd64:"MINSD"
+	// arm64:"FMIND"
+	// riscv64:"FMIN"
+	return min(a, b)
+}
+
+func Float64Max(a, b float64) float64 {
+	// amd64:"MINSD"
+	// arm64:"FMAXD"
+	// riscv64:"FMAX"
+	return max(a, b)
+}
+
+func Float32Min(a, b float32) float32 {
+	// amd64:"MINSS"
+	// arm64:"FMINS"
+	// riscv64:"FMINS"
+	return min(a, b)
+}
+
+func Float32Max(a, b float32) float32 {
+	// amd64:"MINSS"
+	// arm64:"FMAXS"
+	// riscv64:"FMAXS"
+	return max(a, b)
+}