rustc now generates the coverage map and can support (limited)
coverage report generation, at the function level.
Example:
$ BUILD=$HOME/rust/build/x86_64-unknown-linux-gnu
$ $BUILD/stage1/bin/rustc -Zinstrument-coverage \
$HOME/rust/src/test/run-make-fulldeps/instrument-coverage/main.rs
$ LLVM_PROFILE_FILE="main.profraw" ./main
called
$ $BUILD/llvm/bin/llvm-profdata merge -sparse main.profraw -o main.profdata
$ $BUILD/llvm/bin/llvm-cov show --instr-profile=main.profdata main
1| 1|pub fn will_be_called() {
2| 1| println!("called");
3| 1|}
4| |
5| 0|pub fn will_not_be_called() {
6| 0| println!("should not have been called");
7| 0|}
8| |
9| 1|fn main() {
10| 1| let less = 1;
11| 1| let more = 100;
12| 1|
13| 1| if less < more {
14| 1| will_be_called();
15| 1| } else {
16| 1| will_not_be_called();
17| 1| }
18| 1|}
|
||
|---|---|---|
| .. | ||
| back | ||
| coverageinfo | ||
| debuginfo | ||
| llvm | ||
| abi.rs | ||
| allocator.rs | ||
| asm.rs | ||
| attributes.rs | ||
| base.rs | ||
| build.rs | ||
| builder.rs | ||
| callee.rs | ||
| Cargo.toml | ||
| common.rs | ||
| consts.rs | ||
| context.rs | ||
| declare.rs | ||
| intrinsic.rs | ||
| lib.rs | ||
| llvm_util.rs | ||
| metadata.rs | ||
| mono_item.rs | ||
| README.md | ||
| type_.rs | ||
| type_of.rs | ||
| va_arg.rs | ||
| value.rs | ||
The codegen crate contains the code to convert from MIR into LLVM IR,
and then from LLVM IR into machine code. In general it contains code
that runs towards the end of the compilation process.
For more information about how codegen works, see the rustc dev guide.