bors a1dfd2490a Auto merge of #77080 - richkadel:llvm-coverage-counters-2, r=tmandry ... Working branch-level code coverage Add a generalized implementation for computing branch-level coverage spans. This iteration resolves some of the challenges I had identified a few weeks ago. I've tried to implement a solution that is general enough to work for a lot of different graphs/patterns. It's encouraging to see the results on fairly large and complex crates seem to meet my expectations. This may be a "functionally complete" implementation. Except for bug fixes or edge cases I haven't run into yet, the next and essentially final step, I think, is to replace some Counters with CounterExpressions (where their counter values can be computed by adding or subtracting other counters/expressions). Examples of branch-level coverage support enabled in this PR: * https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-cov-reports-base/expected_show_coverage.coverage_of_drop_trait.txt * https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-cov-reports-base/expected_show_coverage.coverage_of_if.txt * https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-cov-reports-base/expected_show_coverage.coverage_of_if_else.txt * https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-cov-reports-base/expected_show_coverage.coverage_of_simple_loop.txt * https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-cov-reports-base/expected_show_coverage.coverage_of_simple_match.txt * ... _and others in the same directory_ Examples of coverage analysis results (MIR spanview files) used to inject counters in the right `BasicBlocks`: * https://htmlpreview.github.io/?https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-mir-cov-html-base/expected_mir_dump.coverage_of_drop_trait/coverage_of_drop_trait.main.-------.InstrumentCoverage.0.html * https://htmlpreview.github.io/?https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-mir-cov-html-base/expected_mir_dump.coverage_of_if/coverage_of_if.main.-------.InstrumentCoverage.0.html * https://htmlpreview.github.io/?https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-mir-cov-html-base/expected_mir_dump.coverage_of_if_else/coverage_of_if_else.main.-------.InstrumentCoverage.0.html * https://htmlpreview.github.io/?https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-mir-cov-html-base/expected_mir_dump.coverage_of_simple_loop/coverage_of_simple_loop.main.-------.InstrumentCoverage.0.html * https://htmlpreview.github.io/?https://github.com/richkadel/rust/blob/llvm-coverage-counters-2/src/test/run-make-fulldeps/instrument-coverage-mir-cov-html-base/expected_mir_dump.coverage_of_simple_match/coverage_of_simple_match.main.-------.InstrumentCoverage.0.html * ... _and others in the same directory_ Here is some sample coverage output after compiling a few real-world crates with the new branch-level coverage features: <img width="801" alt="Screen Shot 2020-09-25 at 1 03 11 PM" src="https://user-images.githubusercontent.com/3827298/94316848-fd882c00-ff39-11ea-9cff-0402d3abd1e7.png"> <img width="721" alt="Screen Shot 2020-09-25 at 1 00 36 PM" src="https://user-images.githubusercontent.com/3827298/94316886-11cc2900-ff3a-11ea-9d03-80b26c8a5173.png"> <img width="889" alt="Screen Shot 2020-09-25 at 12 54 57 PM" src="https://user-images.githubusercontent.com/3827298/94316900-18f33700-ff3a-11ea-8a80-58f67d84b8de.png"> r? `@tmandry` FYI: `@wesleywiser`		2020-10-05 19:34:44 +00:00
..
back	Instruct lld that our @ files are posix-style, not Windows	2020-10-05 08:01:44 -04:00
coverageinfo	Updates to experimental coverage counter injection	2020-10-05 08:02:58 -07:00
debuginfo	Simplify some match statements on `DefPathDataName'	2020-09-25 22:46:15 +01:00
mir	Auto merge of #73453 - erikdesjardins:tuplayout, r=eddyb	2020-09-25 14:42:20 +00:00
traits	Implement Make handle_alloc_error default to panic (for no_std + liballoc)	2020-10-02 09:00:29 +02:00
base.rs	Implement Make handle_alloc_error default to panic (for no_std + liballoc)	2020-10-02 09:00:29 +02:00
common.rs	Remove unused #[allow(...)] statements from compiler/	2020-09-26 01:25:55 +02:00
glue.rs	Change ty.kind to a method	2020-09-04 17:47:51 +02:00
lib.rs	Move target feature whitelist from cg_llvm to cg_ssa	2020-10-04 11:49:00 +02:00
meth.rs	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
mono_item.rs	ty: remove obsolete printer	2020-08-30 18:59:07 +01:00
target_features.rs	Move target feature whitelist from cg_llvm to cg_ssa	2020-10-04 11:49:00 +02:00