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/*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
package codetoanalyze.java.performance;
public class Cost_test {
// Cost: 5
private static int foo_OK() {
int i, j;
i = 17;
j = 31;
return i + j + 3 + 7;
}
// Cost: 17
private static int bar_OK() {
int j = 0;
j++;
j++;
j++;
j = foo_OK();
j++;
return j;
}
// Cost: 25
private static int cond_OK(int i) {
int x;
if (i < 0) {
x = bar_OK();
} else {
x = 1;
}
return x;
}
// Cost: 5
private static void alias_OK() {
int i = 0, j;
j = i;
i = ++i;
}
// Cost: 7
private static void alias2_OK() {
int i = 0, j, z;
j = 1;
z = 2;
j = i;
i = z;
}
// Cost: 1101
private static int loop0_bad() {
for (int i = 0; i < 100; i++) {
alias2_OK();
}
return 0;
}
// Cost: 1203
private static int loop1_bad() {
int k = 100;
for (int i = 0; i < k; i++) {
alias2_OK();
}
return 0;
}
// Expected: Linear bound
private static int FN_loop2(int k) {
for (int i = 0; i < k; i++) {
alias2_OK();
}
return 0;
}
// Expected: constant
private static int loop3(int k) {
for (int i = k; i < k + 18; i++) {
alias2_OK();
}
return 0;
}
// Cost: 218
// Shows that calling many times non expensive function can
// result in an expensive computation
private static int main_bad() {
int k1, k2, k3, k4;
cond_OK(2);
k1 = bar_OK() + foo_OK() + cond_OK(15) * 2;
k2 = bar_OK() + foo_OK() + cond_OK(17) * 3;
k3 = bar_OK() + foo_OK() + cond_OK(11) * 3;
k4 = bar_OK() + foo_OK() + cond_OK(19) * 3;
return 0;
}
// Cost: 1
private static void unitCostFunction() {}
boolean rand() {
if (Math.random() > 0.5) {
return true;
} else {
return false;
}
}
// Cost: Linear to n, not b
void ignore_boolean_symbols_linear(boolean b, int n) {
for (int i = 0; b && i < n; i++) {
b = true;
}
}
// Cost should not include the symbol of b.
void ignore_boolean_symbols_constant1(boolean b) {
for (; b; ) {
if (rand()) {
b = true;
}
}
}
// Cost should not include the symbol of b.
void ignore_boolean_symbols_constant2(boolean b) {
for (; b; ) {
if (rand()) {
b = false;
}
}
}
// Cost should not include the symbol of f.
void ignore_float_symbols_constant(float f) {
for (; f < (float) 1.0; ) {
if (rand()) {
f = (float) 1.0;
}
}
}
// Cost should not include the symbol of d.
void ignore_double_symbols_constant(double d) {
for (; d < (double) 1.0; ) {
if (rand()) {
d = 1.0;
}
}
}
// Cost should not include the symbol of c.
void ignore_character_symbols_constant(char c) {
for (; c < 'z'; ) {
if (rand()) {
c = 'a';
}
}
}
}