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|
LL| |#![feature(coverage_attribute)]
LL| |//@ edition: 2021
LL| |//@ min-llvm-version: 18
LL| |//@ compile-flags: -Zcoverage-options=mcdc
LL| |//@ llvm-cov-flags: --show-branches=count --show-mcdc
LL| |
LL| |// Check that MC/DC instrumentation can gracefully handle conditions that
LL| |// exceed LLVM's limit of 6 conditions per decision.
LL| |//
LL| |// (The limit is enforced in `compiler/rustc_mir_build/src/build/coverageinfo/mcdc.rs`.)
LL| |
LL| 1|fn good() {
LL| 1| // With only 6 conditions, perform full MC/DC instrumentation.
LL| 1| let [a, b, c, d, e, f] = <[bool; 6]>::default();
LL| 1| if a && b && c && d && e && f {
^0 ^0 ^0 ^0 ^0
------------------
| Branch (LL:8): [True: 0, False: 1]
| Branch (LL:13): [True: 0, False: 0]
| Branch (LL:18): [True: 0, False: 0]
| Branch (LL:23): [True: 0, False: 0]
| Branch (LL:28): [True: 0, False: 0]
| Branch (LL:33): [True: 0, False: 0]
------------------
|---> MC/DC Decision Region (LL:8) to (LL:34)
|
| Number of Conditions: 6
| Condition C1 --> (LL:8)
| Condition C2 --> (LL:13)
| Condition C3 --> (LL:18)
| Condition C4 --> (LL:23)
| Condition C5 --> (LL:28)
| Condition C6 --> (LL:33)
|
| Executed MC/DC Test Vectors:
|
| C1, C2, C3, C4, C5, C6 Result
| 1 { F, -, -, -, -, - = F }
|
| C1-Pair: not covered
| C2-Pair: not covered
| C3-Pair: not covered
| C4-Pair: not covered
| C5-Pair: not covered
| C6-Pair: not covered
| MC/DC Coverage for Decision: 0.00%
|
------------------
LL| 0| core::hint::black_box("hello");
LL| 1| }
LL| 1|}
LL| |
LL| 1|fn bad() {
LL| 1| // With 7 conditions, fall back to branch instrumentation only.
LL| 1| let [a, b, c, d, e, f, g] = <[bool; 7]>::default();
LL| 1| if a && b && c && d && e && f && g {
^0 ^0 ^0 ^0 ^0 ^0
------------------
| Branch (LL:8): [True: 0, False: 1]
| Branch (LL:13): [True: 0, False: 0]
| Branch (LL:18): [True: 0, False: 0]
| Branch (LL:23): [True: 0, False: 0]
| Branch (LL:28): [True: 0, False: 0]
| Branch (LL:33): [True: 0, False: 0]
| Branch (LL:38): [True: 0, False: 0]
------------------
LL| 0| core::hint::black_box("hello");
LL| 1| }
LL| 1|}
LL| |
LL| |#[coverage(off)]
LL| |fn main() {
LL| | good();
LL| | bad();
LL| |}
|
