Jokler/cargo-llvm-lines

Count lines of LLVM IR per generic function

cargo-llvm-lines

Count the number of lines of LLVM IR across all instantiations of a generic function. Based on a suggestion from @eddyb on how to count monomorphized functions in order to debug compiler memory usage, executable size and compile time.

<eddyb> unoptimized LLVM IR
<eddyb> first used grep '^define' to get only the lines defining function bodies
<eddyb> then regex replace in my editor to remove everything before @ and everything after (
<eddyb> then sort | uniq -c

Installation

Install with cargo install cargo-llvm-lines.

Output

One line per function with three columns of output:

1. Total number of lines of LLVM IR generated across all instantiations of the function.
2. Number of instantiations of the function. For a generic function, roughly the number of distinct combinations of generic type parameters it is called with.
3. Name of the function.

$ cargo llvm-lines | head -20

   2447  130  core::ptr::drop_in_place
   1720   19  <core::option::Option<T>>::map
    862    2  core::str::pattern::TwoWaySearcher::next
    726    4  <alloc::raw_vec::RawVec<T, A>>::double
    698    4  <alloc::raw_vec::RawVec<T, A>>::reserve
    677    6  <core::result::Result<T, E>>::map
    602    1  cargo_llvm_lines::read_llvm_ir
    598    5  <alloc::vec::Vec<T>>::extend_desugared
    477    1  cargo_llvm_lines::count_lines
    476    9  <alloc::raw_vec::RawVec<T, A>>::dealloc_buffer
    464   10  alloc::heap::box_free
    452    5  <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::spec_extend
    448    1  alloc::slice::merge_sort
    436    1  <std::process::Command as cargo_llvm_lines::PipeTo>::pipe_to
    419    4  <core::slice::Iter<'a, T> as core::iter::iterator::Iterator>::next
    400    1  <core::hash::sip::Sip13Rounds as core::hash::sip::Sip>::d_rounds
    378    9  <alloc::raw_vec::RawVec<T, A>>::current_layout
    362    3  <alloc::raw_vec::RawVec<T, A>>::allocate_in
    354    4  <alloc::vec::Vec<T>>::push
    341    4  <[T] as core::slice::SliceExt>::iter

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in cargo-llvm-lines by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.