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
..
dep_graph	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
hir	Address review comment	2020-09-25 22:48:44 +01:00
ich	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
infer	use relevant span when unifying ConstVarValues	2020-09-23 11:00:44 +02:00
middle	Add support for cmse_nonsecure_entry attribute	2020-09-30 15:48:59 +01:00
mir	Updates to experimental coverage counter injection	2020-10-05 08:02:58 -07:00
query	Remove rustc_allow_const_fn_ptr	2020-09-27 10:46:41 -07:00
traits	remove enum name from ImplSource variants	2020-09-24 19:22:36 +02:00
ty	Auto merge of #77171 - VFLashM:better_sso_structures, r=oli-obk	2020-10-05 17:18:01 +00:00
util	Remove unused #[allow(...)] statements from compiler/	2020-09-26 01:25:55 +02:00
arena.rs	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
lib.rs	/nightly/nightly-rustc	2020-09-23 21:51:56 +02:00
lint.rs	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
macros.rs	mv compiler to compiler/	2020-08-30 18:45:07 +03:00
tests.rs	mv compiler to compiler/	2020-08-30 18:45:07 +03:00