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-rw-r--r--test/opt_branchlikely.go86
1 files changed, 86 insertions, 0 deletions
diff --git a/test/opt_branchlikely.go b/test/opt_branchlikely.go
new file mode 100644
index 0000000..884c349
--- /dev/null
+++ b/test/opt_branchlikely.go
@@ -0,0 +1,86 @@
+// +build amd64
+// errorcheck -0 -d=ssa/likelyadjust/debug=1,ssa/insert_resched_checks/off
+// rescheduling check insertion is turned off because the inserted conditional branches perturb the errorcheck
+
+// Copyright 2016 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 that branches have some prediction properties.
+package foo
+
+func f(x, y, z int) int {
+ a := 0
+ for i := 0; i < x; i++ { // ERROR "Branch prediction rule stay in loop"
+ for j := 0; j < y; j++ { // ERROR "Branch prediction rule stay in loop"
+ a += j
+ }
+ for k := 0; k < z; k++ { // ERROR "Branch prediction rule stay in loop"
+ a -= x + y + z
+ }
+ }
+ return a
+}
+
+func g(x, y, z int) int {
+ a := 0
+ if y == 0 { // ERROR "Branch prediction rule default < call"
+ y = g(y, z, x)
+ } else {
+ y++
+ }
+ if y == x { // ERROR "Branch prediction rule default < call"
+ y = g(y, z, x)
+ } else {
+ }
+ if y == 2 { // ERROR "Branch prediction rule default < call"
+ z++
+ } else {
+ y = g(z, x, y)
+ }
+ if y+z == 3 { // ERROR "Branch prediction rule call < exit"
+ println("ha ha")
+ } else {
+ panic("help help help")
+ }
+ if x != 0 { // ERROR "Branch prediction rule default < ret"
+ for i := 0; i < x; i++ { // ERROR "Branch prediction rule stay in loop"
+ if x == 4 { // ERROR "Branch prediction rule stay in loop"
+ return a
+ }
+ for j := 0; j < y; j++ { // ERROR "Branch prediction rule stay in loop"
+ for k := 0; k < z; k++ { // ERROR "Branch prediction rule stay in loop"
+ a -= j * i
+ }
+ a += j
+ }
+ }
+ }
+ return a
+}
+
+func h(x, y, z int) int {
+ a := 0
+ for i := 0; i < x; i++ { // ERROR "Branch prediction rule stay in loop"
+ for j := 0; j < y; j++ { // ERROR "Branch prediction rule stay in loop"
+ a += j
+ if i == j { // ERROR "Branch prediction rule stay in loop"
+ break
+ }
+ a *= j
+ }
+ for k := 0; k < z; k++ { // ERROR "Branch prediction rule stay in loop"
+ a -= k
+ if i == k {
+ continue
+ }
+ a *= k
+ }
+ }
+ if a > 0 { // ERROR "Branch prediction rule default < call"
+ a = g(x, y, z)
+ } else {
+ a = -a
+ }
+ return a
+}