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// +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
}
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