1 files changed, 117 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/gc/testdata/loadstore_ssa.go b/src/cmd/compile/internal/gc/testdata/loadstore_ssa.go
new file mode 100644
index 0000000000..e0b0b4dfab
--- /dev/null
+++ b/src/cmd/compile/internal/gc/testdata/loadstore_ssa.go
@@ -0,0 +1,117 @@
+// run
+
+// 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.
+
+// Tests load/store ordering
+
+package main
+
+import "fmt"
+
+// testLoadStoreOrder tests for reordering of stores/loads.
+func testLoadStoreOrder() {
+	z := uint32(1000)
+	if testLoadStoreOrder_ssa(&z, 100) == 0 {
+		println("testLoadStoreOrder failed")
+		failed = true
+	}
+}
+func testLoadStoreOrder_ssa(z *uint32, prec uint) int {
+	switch {
+	}
+	old := *z         // load
+	*z = uint32(prec) // store
+	if *z < old {     // load
+		return 1
+	}
+	return 0
+}
+
+func testStoreSize() {
+	a := [4]uint16{11, 22, 33, 44}
+	testStoreSize_ssa(&a[0], &a[2], 77)
+	want := [4]uint16{77, 22, 33, 44}
+	if a != want {
+		fmt.Println("testStoreSize failed.  want =", want, ", got =", a)
+		failed = true
+	}
+}
+func testStoreSize_ssa(p *uint16, q *uint16, v uint32) {
+	switch {
+	}
+	// Test to make sure that (Store ptr (Trunc32to16 val) mem)
+	// does not end up as a 32-bit store.  It must stay a 16 bit store
+	// even when Trunc32to16 is rewritten to be a nop.
+	// To ensure that we get rewrite the Trunc32to16 before
+	// we rewrite the Store, we force the truncate into an
+	// earlier basic block by using it on both branches.
+	w := uint16(v)
+	if p != nil {
+		*p = w
+	} else {
+		*q = w
+	}
+}
+
+var failed = false
+
+func testExtStore_ssa(p *byte, b bool) int {
+	switch {
+	}
+	x := *p
+	*p = 7
+	if b {
+		return int(x)
+	}
+	return 0
+}
+
+func testExtStore() {
+	const start = 8
+	var b byte = start
+	if got := testExtStore_ssa(&b, true); got != start {
+		fmt.Println("testExtStore failed.  want =", start, ", got =", got)
+		failed = true
+	}
+}
+
+var b int
+
+// testDeadStorePanic_ssa ensures that we don't optimize away stores
+// that could be read by after recover().  Modeled after fixedbugs/issue1304.
+func testDeadStorePanic_ssa(a int) (r int) {
+	switch {
+	}
+	defer func() {
+		recover()
+		r = a
+	}()
+	a = 2      // store
+	b := a - a // optimized to zero
+	c := 4
+	a = c / b // store, but panics
+	a = 3     // store
+	r = a
+	return
+}
+
+func testDeadStorePanic() {
+	if want, got := 2, testDeadStorePanic_ssa(1); want != got {
+		fmt.Println("testDeadStorePanic failed.  want =", want, ", got =", got)
+		failed = true
+	}
+}
+
+func main() {
+
+	testLoadStoreOrder()
+	testStoreSize()
+	testExtStore()
+	testDeadStorePanic()
+
+	if failed {
+		panic("failed")
+	}
+}