1 files changed, 149 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/test/testdata/ctl_test.go b/src/cmd/compile/internal/test/testdata/ctl_test.go
new file mode 100644
index 0000000000..16d571ce2c
--- /dev/null
+++ b/src/cmd/compile/internal/test/testdata/ctl_test.go
@@ -0,0 +1,149 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test control flow
+
+package main
+
+import "testing"
+
+// nor_ssa calculates NOR(a, b).
+// It is implemented in a way that generates
+// phi control values.
+func nor_ssa(a, b bool) bool {
+	var c bool
+	if a {
+		c = true
+	}
+	if b {
+		c = true
+	}
+	if c {
+		return false
+	}
+	return true
+}
+
+func testPhiControl(t *testing.T) {
+	tests := [...][3]bool{ // a, b, want
+		{false, false, true},
+		{true, false, false},
+		{false, true, false},
+		{true, true, false},
+	}
+	for _, test := range tests {
+		a, b := test[0], test[1]
+		got := nor_ssa(a, b)
+		want := test[2]
+		if want != got {
+			t.Errorf("nor(%t, %t)=%t got %t", a, b, want, got)
+		}
+	}
+}
+
+func emptyRange_ssa(b []byte) bool {
+	for _, x := range b {
+		_ = x
+	}
+	return true
+}
+
+func testEmptyRange(t *testing.T) {
+	if !emptyRange_ssa([]byte{}) {
+		t.Errorf("emptyRange_ssa([]byte{})=false, want true")
+	}
+}
+
+func switch_ssa(a int) int {
+	ret := 0
+	switch a {
+	case 5:
+		ret += 5
+	case 4:
+		ret += 4
+	case 3:
+		ret += 3
+	case 2:
+		ret += 2
+	case 1:
+		ret += 1
+	}
+	return ret
+
+}
+
+func fallthrough_ssa(a int) int {
+	ret := 0
+	switch a {
+	case 5:
+		ret++
+		fallthrough
+	case 4:
+		ret++
+		fallthrough
+	case 3:
+		ret++
+		fallthrough
+	case 2:
+		ret++
+		fallthrough
+	case 1:
+		ret++
+	}
+	return ret
+
+}
+
+func testFallthrough(t *testing.T) {
+	for i := 0; i < 6; i++ {
+		if got := fallthrough_ssa(i); got != i {
+			t.Errorf("fallthrough_ssa(i) = %d, wanted %d", got, i)
+		}
+	}
+}
+
+func testSwitch(t *testing.T) {
+	for i := 0; i < 6; i++ {
+		if got := switch_ssa(i); got != i {
+			t.Errorf("switch_ssa(i) = %d, wanted %d", got, i)
+		}
+	}
+}
+
+type junk struct {
+	step int
+}
+
+// flagOverwrite_ssa is intended to reproduce an issue seen where a XOR
+// was scheduled between a compare and branch, clearing flags.
+//go:noinline
+func flagOverwrite_ssa(s *junk, c int) int {
+	if '0' <= c && c <= '9' {
+		s.step = 0
+		return 1
+	}
+	if c == 'e' || c == 'E' {
+		s.step = 0
+		return 2
+	}
+	s.step = 0
+	return 3
+}
+
+func testFlagOverwrite(t *testing.T) {
+	j := junk{}
+	if got := flagOverwrite_ssa(&j, ' '); got != 3 {
+		t.Errorf("flagOverwrite_ssa = %d, wanted 3", got)
+	}
+}
+
+func TestCtl(t *testing.T) {
+	testPhiControl(t)
+	testEmptyRange(t)
+
+	testSwitch(t)
+	testFallthrough(t)
+
+	testFlagOverwrite(t)
+}