chore: checkpoint before Python removal

vendor/psm/examples/info.rs

@@ -0,0 +1,20 @@
+extern crate psm;
+
+psm::psm_stack_information! {
+    yes {
+        fn main() {
+            println!("Stack is {:?} and is at {:p} currently",
+                     psm::StackDirection::new(), psm::stack_pointer());
+        }
+    }
+    no {
+        fn main() {
+            eprintln!("Stack information not supported by this target");
+        }
+    }
+}
+
+#[test]
+fn run_example() {
+    main();
+}

vendor/psm/examples/on_stack_fibo.rs

@@ -0,0 +1,77 @@
+extern crate psm;
+
+psm::psm_stack_manipulation! {
+    yes {
+        use std::alloc;
+
+        #[inline(never)]
+        fn fib(n: usize, stack_limit: *mut u8) -> Option<u64> {
+            // match psm::StackDirection::new() {
+            //     psm::StackDirection::Ascending => if psm::stack_pointer() > stack_limit {
+            //         return None;
+            //     }
+            //     psm::StackDirection::Descending => if psm::stack_pointer() < stack_limit {
+            //         return None;
+            //     }
+            // }
+
+            match n {
+                0 => Some(0),
+                1 => Some(1),
+                _ => fib(n - 1, stack_limit).and_then(|x| fib(n - 2, stack_limit).map(|y| x + y)),
+            }
+        }
+
+        const STACK_ALIGN: usize = 4096;
+        const STACK_REDLINE: usize = 512;
+        const FIB_COUNTS: [(usize, u64); 3] = [
+            (8, 21),
+            (16, 987),
+            (32, 2178309),
+        ];
+
+
+        fn main() {
+            let mut stack_size = 1024 * 128;
+            unsafe {
+                for &(n, expected) in FIB_COUNTS.iter() {
+                    loop {
+                        println!("fib({}) with {} bytes of stack", n, stack_size - STACK_REDLINE);
+                        let layout = alloc::Layout::from_size_align(stack_size, STACK_ALIGN).unwrap();
+                        let new_stack = alloc::alloc(layout);
+                        assert!(!new_stack.is_null(), "allocations must succeed!");
+                        let max_stack = match psm::StackDirection::new() {
+                            psm::StackDirection::Ascending =>
+                                new_stack.offset((stack_size - STACK_REDLINE) as isize),
+                            psm::StackDirection::Descending =>
+                                new_stack.offset(STACK_REDLINE as isize),
+                        };
+                        let result = psm::on_stack(new_stack, stack_size, || {
+                            fib(n, max_stack)
+                        });
+                        alloc::dealloc(new_stack, layout);
+                        if let Some(res) = result {
+                            assert_eq!(res, expected);
+                            println!("fib({}) = {}", n, res);
+                            break;
+                        } else {
+                            println!("Stack not large enough!");
+                            stack_size *= 2;
+                        }
+                    }
+                }
+            }
+        }
+
+    }
+    no {
+        fn main() {
+            eprintln!("Stack manipulation not supported by this target");
+        }
+    }
+}
+
+#[test]
+fn run_example() {
+    main()
+}

vendor/psm/examples/on_stack_fibo_alloc_each_frame.rs

@@ -0,0 +1,53 @@
+extern crate psm;
+
+psm::psm_stack_manipulation! {
+    yes {
+        use std::alloc;
+
+        const STACK_ALIGN: usize = 4096;
+        const FRAME_SIZE: usize = 4096;
+        const FIB_COUNTS: [(usize, u64); 3] = [
+            (8, 21),
+            (16, 987),
+            (24, 46368),
+        ];
+
+        #[inline(never)]
+        fn fib(n: usize) -> u64 {
+            unsafe {
+                let layout = alloc::Layout::from_size_align(FRAME_SIZE, STACK_ALIGN).unwrap();
+                let new_stack = alloc::alloc(layout);
+                assert!(!new_stack.is_null(), "allocations must succeed!");
+                let r = match n {
+                    0 => 0,
+                    1 => 1,
+                    _ => {
+                        psm::on_stack(new_stack, FRAME_SIZE, || {
+                            fib(n - 1) + fib(n - 2)
+                        })
+                    }
+                };
+                alloc::dealloc(new_stack, layout);
+                r
+            }
+        }
+
+        fn main() {
+            for &(n, expected) in FIB_COUNTS.iter() {
+                let res = fib(n);
+                assert_eq!(res, expected);
+                println!("fib({}) = {}", n, res);
+            }
+        }
+    }
+    no {
+        fn main() {
+            eprintln!("Stack manipulation not supported by this target");
+        }
+    }
+}
+
+#[test]
+fn run_example() {
+    main()
+}

vendor/psm/examples/panics.rs

@@ -0,0 +1,52 @@
+extern crate psm;
+
+use std::panic;
+
+const CHAIN_DEPTH: usize = 16;
+
+psm::psm_stack_manipulation! {
+    yes {
+        use std::alloc;
+        const STACK_ALIGN: usize = 4096;
+        // Generating backraces (because of RUST_BACKTRACE) create a few quite large frames, so it is
+        // important, that all frames have sufficient amount of available memory to not run over the
+        // stack...
+        const FRAME_SIZE: usize = 4096 * 10;
+
+        fn panic_chain(depth: usize) {
+            if depth == 0 {
+                panic!("full chain!");
+            } else {
+                unsafe {
+                    let layout = alloc::Layout::from_size_align(FRAME_SIZE, STACK_ALIGN).unwrap();
+                    let new_stack = alloc::alloc(layout);
+                    assert!(!new_stack.is_null(), "allocations must succeed!");
+                    let p = psm::on_stack(new_stack, FRAME_SIZE, || {
+                        panic::catch_unwind(|| {
+                            panic_chain(depth - 1);
+                        })
+                    });
+                    alloc::dealloc(new_stack, layout);
+                    p.map_err(panic::resume_unwind).unwrap()
+                }
+            }
+        }
+
+        fn main() {
+            panic_chain(CHAIN_DEPTH);
+        }
+
+        #[test]
+        fn run_example() {
+            assert!(panic::catch_unwind(|| {
+                panic_chain(CHAIN_DEPTH);
+            }).is_err(), "Panic did not propagate!");
+        }
+    }
+
+    no {
+        fn main() {
+            eprintln!("Stack manipulation not supported by this target");
+        }
+    }
+}

vendor/psm/examples/replace_stack_1.rs

@@ -0,0 +1,33 @@
+extern crate psm;
+
+psm::psm_stack_manipulation! {
+    yes {
+        use std::alloc;
+
+        const STACK_SIZE: usize = 4096 * 64;
+        const STACK_ALIGN: usize = 4096;
+
+        fn main() {
+            println!("current stack pointer is {:p}", psm::stack_pointer());
+            unsafe {
+                let new_stack = alloc::alloc(alloc::Layout::from_size_align(STACK_SIZE, STACK_ALIGN).unwrap());
+                println!("new stack is between {:p} and {:p}", new_stack, new_stack.offset(STACK_SIZE as isize));
+                psm::replace_stack(new_stack, STACK_SIZE, || {
+                    println!("after replacement stack pointer is {:p}", psm::stack_pointer());
+                    ::std::process::exit(0);
+                });
+            }
+        }
+    }
+    no {
+        fn main() {
+            eprintln!("Stack manipulation not supported by this target");
+        }
+    }
+}
+
+#[test]
+fn run_example() {
+    // NOTE: intentionally out-of-processes, as the example exits with `process::exit(0)`.
+    main()
+}

vendor/psm/examples/thread.rs

@@ -0,0 +1,60 @@
+extern crate psm;
+
+psm::psm_stack_manipulation! {
+    yes {
+        use std::alloc;
+
+        const STACK_ALIGN: usize = 4096;
+        const FRAME_SIZE: usize = 4096;
+        const FIB_COUNTS: [(usize, u64); 3] = [
+            (8, 21),
+            (16, 987),
+            (24, 46368),
+        ];
+
+        #[inline(never)]
+        fn fib(n: usize) -> u64 {
+            unsafe {
+                let layout = alloc::Layout::from_size_align(FRAME_SIZE, STACK_ALIGN).unwrap();
+                let new_stack = alloc::alloc(layout);
+                assert!(!new_stack.is_null(), "allocations must succeed!");
+                let r = match n {
+                    0 => 0,
+                    1 => 1,
+                    _ => {
+                        psm::on_stack(new_stack, FRAME_SIZE, || {
+                            fib(n - 1) + fib(n - 2)
+                        })
+                    }
+                };
+                alloc::dealloc(new_stack, layout);
+                r
+            }
+        }
+
+        fn main() {
+            for (n, expected, handle) in FIB_COUNTS.iter().map(|&(n, expected)|
+                (n, expected, std::thread::spawn(move || {
+                    fib(n)
+                }))
+            ) {
+                if let Ok(res) = handle.join() {
+                    assert_eq!(res, expected);
+                    println!("fib({}) = {}", n, res);
+                } else {
+                    panic!("joining a thread returned an Err");
+                }
+            }
+        }
+    }
+    no {
+        fn main() {
+            eprintln!("Stack manipulation not supported by this target");
+        }
+    }
+}
+
+#[test]
+fn run_example() {
+    main()
+}