| 1 | use std::collections::BTreeSet; |
| 2 | use std::path::PathBuf; |
| 3 | |
| 4 | use armfortas::driver::OptLevel; |
| 5 | use armfortas::testing::{capture_from_path, CaptureRequest, CapturedStage, Stage}; |
| 6 | |
| 7 | fn fixture(name: &str) -> PathBuf { |
| 8 | let path = PathBuf::from("test_programs").join(name); |
| 9 | assert!(path.exists(), "missing test fixture {}", path.display()); |
| 10 | path |
| 11 | } |
| 12 | |
| 13 | fn capture_text(request: CaptureRequest, stage: Stage) -> String { |
| 14 | let result = capture_from_path(&request).expect("capture should succeed"); |
| 15 | match result.get(stage) { |
| 16 | Some(CapturedStage::Text(text)) => text.clone(), |
| 17 | Some(CapturedStage::Run(_)) => panic!("expected text stage for {}", stage.as_str()), |
| 18 | None => panic!("missing requested stage {}", stage.as_str()), |
| 19 | } |
| 20 | } |
| 21 | |
| 22 | fn function_section<'a>(ir: &'a str, name: &str) -> &'a str { |
| 23 | let header = format!(" func @{}", name); |
| 24 | let start = ir |
| 25 | .find(&header) |
| 26 | .unwrap_or_else(|| panic!("missing function section for {}", name)); |
| 27 | let rest = &ir[start..]; |
| 28 | let end = rest |
| 29 | .find("\n }\n") |
| 30 | .unwrap_or_else(|| panic!("unterminated function section for {}", name)); |
| 31 | &rest[..end + "\n }".len()] |
| 32 | } |
| 33 | |
| 34 | fn function_sections(ir: &str) -> Vec<&str> { |
| 35 | ir.match_indices(" func @") |
| 36 | .map(|(idx, _)| { |
| 37 | let rest = &ir[idx..]; |
| 38 | let end = rest |
| 39 | .find("\n }\n") |
| 40 | .unwrap_or_else(|| panic!("unterminated function section in:\n{}", rest)); |
| 41 | &rest[..end + "\n }".len()] |
| 42 | }) |
| 43 | .collect() |
| 44 | } |
| 45 | |
| 46 | fn function_name<'a>(func_section: &'a str) -> &'a str { |
| 47 | let header = func_section.lines().next().expect("function header").trim(); |
| 48 | let rest = header |
| 49 | .strip_prefix("func @") |
| 50 | .expect("function header prefix"); |
| 51 | let end = rest |
| 52 | .find(|ch: char| ch == ' ' || ch == '(') |
| 53 | .unwrap_or(rest.len()); |
| 54 | &rest[..end] |
| 55 | } |
| 56 | |
| 57 | fn count(haystack: &str, needle: &str) -> usize { |
| 58 | haystack.matches(needle).count() |
| 59 | } |
| 60 | |
| 61 | #[test] |
| 62 | fn o2_reuses_pure_recursive_call_in_program_caller() { |
| 63 | let source = fixture("pure_recursive_reuse.f90"); |
| 64 | |
| 65 | let raw_ir = capture_text( |
| 66 | CaptureRequest { |
| 67 | input: source.clone(), |
| 68 | requested: BTreeSet::from([Stage::Ir]), |
| 69 | opt_level: OptLevel::O0, |
| 70 | }, |
| 71 | Stage::Ir, |
| 72 | ); |
| 73 | let opt_ir = capture_text( |
| 74 | CaptureRequest { |
| 75 | input: source, |
| 76 | requested: BTreeSet::from([Stage::OptIr]), |
| 77 | opt_level: OptLevel::O2, |
| 78 | }, |
| 79 | Stage::OptIr, |
| 80 | ); |
| 81 | let raw_sections = function_sections(&raw_ir); |
| 82 | assert_eq!( |
| 83 | raw_sections.len(), |
| 84 | 2, |
| 85 | "raw IR should include the program body plus one contained pure helper:\n{}", |
| 86 | raw_ir |
| 87 | ); |
| 88 | let helper_name = function_name(raw_sections[1]); |
| 89 | |
| 90 | let raw_main = function_section(&raw_ir, "__prog_pure_recursive_reuse"); |
| 91 | let opt_main = function_section(&opt_ir, "__prog_pure_recursive_reuse"); |
| 92 | |
| 93 | let raw_pure_calls = count(raw_main, &format!("call @{}(", helper_name)); |
| 94 | let opt_pure_calls = count(opt_main, &format!("call @{}(", helper_name)); |
| 95 | |
| 96 | assert_eq!( |
| 97 | raw_pure_calls, 2, |
| 98 | "lowered caller should materialize two recursive PURE calls before optimization:\n{}", |
| 99 | raw_main |
| 100 | ); |
| 101 | assert_eq!( |
| 102 | opt_pure_calls, 1, |
| 103 | "O2 optimized caller should reuse the repeated PURE call result:\n{}", |
| 104 | opt_main |
| 105 | ); |
| 106 | } |
| 107 |