forked from rust-lang/rust
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Rollup merge of rust-lang#122405 - celinval:smir-new-const, r=oli-obk
Add methods to create StableMIR constant I've been experimenting with transforming the StableMIR to instrument the code with potential UB checks. The modified body will only be used by our analysis tool, however, constants in StableMIR must be backed by rustc constants. Thus, I'm adding a few functions to build constants, such as building string and other primitives. One question I have is whether we should create a global allocation instead for strings. r? ````@oli-obk````
- Loading branch information
Showing
4 changed files
with
237 additions
and
12 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,147 @@ | ||
| //@ run-pass | ||
| //! Test a few methods to transform StableMIR. | ||
|
|
||
| //@ ignore-stage1 | ||
| //@ ignore-cross-compile | ||
| //@ ignore-remote | ||
| //@ ignore-windows-gnu mingw has troubles with linking https://github.com/rust-lang/rust/pull/116837 | ||
|
|
||
| #![feature(rustc_private)] | ||
| #![feature(assert_matches)] | ||
| #![feature(control_flow_enum)] | ||
| #![feature(ascii_char, ascii_char_variants)] | ||
|
|
||
| extern crate rustc_hir; | ||
| #[macro_use] | ||
| extern crate rustc_smir; | ||
| extern crate rustc_driver; | ||
| extern crate rustc_interface; | ||
| extern crate stable_mir; | ||
|
|
||
| use rustc_smir::rustc_internal; | ||
| use stable_mir::mir::alloc::GlobalAlloc; | ||
| use stable_mir::mir::mono::Instance; | ||
| use stable_mir::mir::{Body, Constant, Operand, Rvalue, StatementKind, TerminatorKind}; | ||
| use stable_mir::ty::{Const, ConstantKind}; | ||
| use stable_mir::{CrateDef, CrateItems, ItemKind}; | ||
| use std::convert::TryFrom; | ||
| use std::io::Write; | ||
| use std::ops::ControlFlow; | ||
|
|
||
| const CRATE_NAME: &str = "input"; | ||
|
|
||
| /// This function uses the Stable MIR APIs to transform the MIR. | ||
| fn test_transform() -> ControlFlow<()> { | ||
| // Find items in the local crate. | ||
| let items = stable_mir::all_local_items(); | ||
|
|
||
| // Test fn_abi | ||
| let target_fn = *get_item(&items, (ItemKind::Fn, "dummy")).unwrap(); | ||
| let instance = Instance::try_from(target_fn).unwrap(); | ||
| let body = instance.body().unwrap(); | ||
| check_msg(&body, "oops"); | ||
|
|
||
| let new_msg = "new panic message"; | ||
| let new_body = change_panic_msg(body, new_msg); | ||
| check_msg(&new_body, new_msg); | ||
|
|
||
| ControlFlow::Continue(()) | ||
| } | ||
|
|
||
| /// Check that the body panic message matches the given message. | ||
| fn check_msg(body: &Body, expected: &str) { | ||
| let msg = body | ||
| .blocks | ||
| .iter() | ||
| .find_map(|bb| match &bb.terminator.kind { | ||
| TerminatorKind::Call { args, .. } => { | ||
| assert_eq!(args.len(), 1, "Expected panic message, but found {args:?}"); | ||
| let msg_const = match &args[0] { | ||
| Operand::Constant(msg_const) => msg_const, | ||
| Operand::Copy(place) | Operand::Move(place) => { | ||
| assert!(place.projection.is_empty()); | ||
| bb.statements | ||
| .iter() | ||
| .find_map(|stmt| match &stmt.kind { | ||
| StatementKind::Assign( | ||
| destination, | ||
| Rvalue::Use(Operand::Constant(msg_const)), | ||
| ) if destination == place => Some(msg_const), | ||
| _ => None, | ||
| }) | ||
| .unwrap() | ||
| } | ||
| }; | ||
| let ConstantKind::Allocated(alloc) = msg_const.literal.kind() else { | ||
| unreachable!() | ||
| }; | ||
| assert_eq!(alloc.provenance.ptrs.len(), 1); | ||
|
|
||
| let alloc_prov_id = alloc.provenance.ptrs[0].1 .0; | ||
| let GlobalAlloc::Memory(val) = GlobalAlloc::from(alloc_prov_id) else { | ||
| unreachable!() | ||
| }; | ||
| let bytes = val.raw_bytes().unwrap(); | ||
| Some(std::str::from_utf8(&bytes).unwrap().to_string()) | ||
| } | ||
| _ => None, | ||
| }) | ||
| .expect("Failed to find panic message"); | ||
| assert_eq!(&msg, expected); | ||
| } | ||
|
|
||
| /// Modify body to use a different panic message. | ||
| fn change_panic_msg(mut body: Body, new_msg: &str) -> Body { | ||
| for bb in &mut body.blocks { | ||
| match &mut bb.terminator.kind { | ||
| TerminatorKind::Call { args, .. } => { | ||
| let new_const = Const::from_str(new_msg); | ||
| args[0] = Operand::Constant(Constant { | ||
| literal: new_const, | ||
| span: bb.terminator.span, | ||
| user_ty: None, | ||
| }); | ||
| } | ||
| _ => {} | ||
| } | ||
| } | ||
| body | ||
| } | ||
|
|
||
| fn get_item<'a>( | ||
| items: &'a CrateItems, | ||
| item: (ItemKind, &str), | ||
| ) -> Option<&'a stable_mir::CrateItem> { | ||
| items.iter().find(|crate_item| (item.0 == crate_item.kind()) && crate_item.name() == item.1) | ||
| } | ||
|
|
||
| /// This test will generate and analyze a dummy crate using the stable mir. | ||
| /// For that, it will first write the dummy crate into a file. | ||
| /// Then it will create a `StableMir` using custom arguments and then | ||
| /// it will run the compiler. | ||
| fn main() { | ||
| let path = "transform_input.rs"; | ||
| generate_input(&path).unwrap(); | ||
| let args = vec![ | ||
| "rustc".to_string(), | ||
| "--crate-type=lib".to_string(), | ||
| "--crate-name".to_string(), | ||
| CRATE_NAME.to_string(), | ||
| path.to_string(), | ||
| ]; | ||
| run!(args, test_transform).unwrap(); | ||
| } | ||
|
|
||
| fn generate_input(path: &str) -> std::io::Result<()> { | ||
| let mut file = std::fs::File::create(path)?; | ||
| write!( | ||
| file, | ||
| r#" | ||
| #![feature(panic_internals)] | ||
| pub fn dummy() {{ | ||
| core::panicking::panic_str("oops"); | ||
| }} | ||
| "# | ||
| )?; | ||
| Ok(()) | ||
| } |