ab45885dec
coverage: Explicitly test the coverage maps produced by codegen/LLVM Our existing coverage tests verify the output of end-to-end coverage reports, but we don't have any way to test the specific mapping information (code regions and their associated counters) that are emitted by `rustc_codegen_llvm` and LLVM. That makes it harder to to be confident in changes that would modify those mappings (whether deliberately or accidentally). This PR addresses that by adding a new `coverage-map` test suite that does the following: - Compiles test files to LLVM IR assembly (`.ll`) - Feeds those IR files to a custom tool (`src/tools/coverage-dump`) that extracts and decodes coverage mappings, and prints them in a more human-readable format - Checks the output of that tool against known-good snapshots --- I recommend excluding the last commit while reviewing the main changes, because that last commit is just ~40 test files copied over from `tests/run-coverage`, plus their blessed coverage-map snapshots and a readme file. Those snapshots aren't really intended to be checked by hand; they're mostly there to increase the chances that an unintended change to coverage maps will be observable (even if it requires relatively specific circumstances to manifest). |
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| .. | ||
| bootstrap | ||
| ci | ||
| doc | ||
| etc | ||
| librustdoc | ||
| llvm-project@50eecd007f | ||
| rustdoc-json-types | ||
| tools | ||
| README.md | ||
| stage0.json | ||
| version | ||
This directory contains some source code for the Rust project, including:
- The bootstrapping build system
- Various submodules for tools, like cargo, tidy, etc.
For more information on how various parts of the compiler work, see the rustc dev guide.