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|
LL| |#![feature(coverage_attribute)]
LL| |//@ edition: 2021
LL| |//@ compile-flags: -Zcoverage-options=branch
LL| |//@ llvm-cov-flags: --show-branches=count
LL| |
LL| |// Tests for branch coverage of the lazy boolean operators `&&` and `||`,
LL| |// as ordinary expressions that aren't part of an `if` condition or similar.
LL| |
LL| |use core::hint::black_box;
LL| |
LL| |// Helper macro to prevent start-of-function spans from being merged into
LL| |// spans on the lines we care about.
LL| |macro_rules! no_merge {
LL| | () => {
LL| | for _ in 0..1 {}
LL| | };
LL| |}
LL| |
LL| 15|fn branch_and(a: bool, b: bool) {
LL| 15| no_merge!();
LL| |
LL| | // |13 |18 (no branch)
LL| 15| let c = a && b;
^12
------------------
| Branch (LL:13): [True: 12, False: 3]
------------------
LL| 15| black_box(c);
LL| 15|}
LL| |
LL| 15|fn branch_or(a: bool, b: bool) {
LL| 15| no_merge!();
LL| |
LL| | // |13 |18 (no branch)
LL| 15| let c = a || b;
^3
------------------
| Branch (LL:13): [True: 12, False: 3]
------------------
LL| 15| black_box(c);
LL| 15|}
LL| |
LL| |// Test for chaining one operator several times.
LL| 16|fn chain(x: u32) {
LL| 16| no_merge!();
LL| |
LL| | // |13 |22 |31 |40 (no branch)
LL| 16| let c = x > 1 && x > 2 && x > 4 && x > 8;
^14 ^13 ^11
------------------
| Branch (LL:13): [True: 14, False: 2]
| Branch (LL:22): [True: 13, False: 1]
| Branch (LL:31): [True: 11, False: 2]
------------------
LL| 16| black_box(c);
LL| |
LL| | // |13 |22 |31 |40 (no branch)
LL| 16| let d = x < 1 || x < 2 || x < 4 || x < 8;
^15 ^14 ^12
------------------
| Branch (LL:13): [True: 1, False: 15]
| Branch (LL:22): [True: 1, False: 14]
| Branch (LL:31): [True: 2, False: 12]
------------------
LL| 16| black_box(d);
LL| 16|}
LL| |
LL| |// Test for nested combinations of different operators.
LL| 16|fn nested_mixed(x: u32) {
LL| 16| no_merge!();
LL| |
LL| | // |14 |23 |35 |44 (no branch)
LL| 16| let c = (x < 4 || x >= 9) && (x < 2 || x >= 10);
^12 ^11 ^9
------------------
| Branch (LL:14): [True: 4, False: 12]
| Branch (LL:23): [True: 7, False: 5]
| Branch (LL:35): [True: 2, False: 9]
------------------
LL| 16| black_box(c);
LL| |
LL| | // |14 |23 |34 |44 (no branch)
LL| 16| let d = (x < 4 && x < 1) || (x >= 8 && x >= 10);
^4 ^15 ^8
------------------
| Branch (LL:14): [True: 4, False: 12]
| Branch (LL:23): [True: 1, False: 3]
| Branch (LL:34): [True: 8, False: 7]
------------------
LL| 16| black_box(d);
LL| 16|}
LL| |
LL| |#[coverage(off)]
LL| |fn main() {
LL| | // Use each set of arguments (2^n) times, so that each combination has a
LL| | // unique sum, and we can use those sums to verify expected control flow.
LL| | // 1x (false, false)
LL| | // 2x (false, true)
LL| | // 4x (true, false)
LL| | // 8x (true, true)
LL| | for a in [false, true, true, true, true] {
LL| | for b in [false, true, true] {
LL| | branch_and(a, b);
LL| | branch_or(a, b);
LL| | }
LL| | }
LL| |
LL| | for x in 0..16 {
LL| | chain(x);
LL| | nested_mixed(x);
LL| | }
LL| |}
|
