Move /src/test to /tests

51 files changed, 2504 insertions, 0 deletions

diff --git a/tests/run-make/coverage/WARNING_KEEP_NAMES_SHORT.txt b/tests/run-make/coverage/WARNING_KEEP_NAMES_SHORT.txt
new file mode 100644
index 00000000000..6a1403b8a00
--- /dev/null
+++ b/tests/run-make/coverage/WARNING_KEEP_NAMES_SHORT.txt
@@ -0,0 +1,10 @@
+IMPORTANT: The Rust test programs in this directory generate various output
+files in the `../coverage*` directories (`expected` and `actual` files).
+
+Microsoft Windows has a relatively short limit on file paths (not individual
+path components, but the entire path). The files generated by these
+`../coverage*` tests typically have file paths that include the program
+source file name plus function and type names (depending on the program).
+
+Keep the test file names short, and keep function names and other symbols
+short as well, to avoid hitting the Windows limits.
diff --git a/tests/run-make/coverage/abort.rs b/tests/run-make/coverage/abort.rs
new file mode 100644
index 00000000000..3dac43df8f3
--- /dev/null
+++ b/tests/run-make/coverage/abort.rs
@@ -0,0 +1,66 @@
+#![feature(c_unwind)]
+#![allow(unused_assignments)]
+
+extern "C" fn might_abort(should_abort: bool) {
+    if should_abort {
+        println!("aborting...");
+        panic!("panics and aborts");
+    } else {
+        println!("Don't Panic");
+    }
+}
+
+fn main() -> Result<(), u8> {
+    let mut countdown = 10;
+    while countdown > 0 {
+        if countdown < 5 {
+            might_abort(false);
+        }
+        // See discussion (below the `Notes` section) on coverage results for the closing brace.
+        if countdown < 5 { might_abort(false); } // Counts for different regions on one line.
+        // For the following example, the closing brace is the last character on the line.
+        // This shows the character after the closing brace is highlighted, even if that next
+        // character is a newline.
+        if countdown < 5 { might_abort(false); }
+        countdown -= 1;
+    }
+    Ok(())
+}
+
+// Notes:
+//   1. Compare this program and its coverage results to those of the similar tests
+//      `panic_unwind.rs` and `try_error_result.rs`.
+//   2. This test confirms the coverage generated when a program includes `TerminatorKind::Abort`.
+//   3. The test does not invoke the abort. By executing to a successful completion, the coverage
+//      results show where the program did and did not execute.
+//   4. If the program actually aborted, the coverage counters would not be saved (which "works as
+//      intended"). Coverage results would show no executed coverage regions.
+//   6. If `should_abort` is `true` and the program aborts, the program exits with a `132` status
+//      (on Linux at least).
+
+/*
+
+Expect the following coverage results:
+
+```text
+    16|     11|    while countdown > 0 {
+    17|     10|        if countdown < 5 {
+    18|      4|            might_abort(false);
+    19|      6|        }
+```
+
+This is actually correct.
+
+The condition `countdown < 5` executed 10 times (10 loop iterations).
+
+It evaluated to `true` 4 times, and executed the `might_abort()` call.
+
+It skipped the body of the `might_abort()` call 6 times. If an `if` does not include an explicit
+`else`, the coverage implementation injects a counter, at the character immediately after the `if`s
+closing brace, to count the "implicit" `else`. This is the only way to capture the coverage of the
+non-true condition.
+
+As another example of why this is important, say the condition was `countdown < 50`, which is always
+`true`. In that case, we wouldn't have a test for what happens if `might_abort()` is not called.
+The closing brace would have a count of `0`, highlighting the missed coverage.
+*/
diff --git a/tests/run-make/coverage/assert.rs b/tests/run-make/coverage/assert.rs
new file mode 100644
index 00000000000..c85f2748eb9
--- /dev/null
+++ b/tests/run-make/coverage/assert.rs
@@ -0,0 +1,32 @@
+#![allow(unused_assignments)]
+// expect-exit-status-101
+
+fn might_fail_assert(one_plus_one: u32) {
+    println!("does 1 + 1 = {}?", one_plus_one);
+    assert_eq!(1 + 1, one_plus_one, "the argument was wrong");
+}
+
+fn main() -> Result<(),u8> {
+    let mut countdown = 10;
+    while countdown > 0 {
+        if countdown == 1 {
+            might_fail_assert(3);
+        } else if countdown < 5 {
+            might_fail_assert(2);
+        }
+        countdown -= 1;
+    }
+    Ok(())
+}
+
+// Notes:
+//   1. Compare this program and its coverage results to those of the very similar test
+//      `panic_unwind.rs`, and similar tests `abort.rs` and `try_error_result.rs`.
+//   2. This test confirms the coverage generated when a program passes or fails an `assert!()` or
+//      related `assert_*!()` macro.
+//   3. Notably, the `assert` macros *do not* generate `TerminatorKind::Assert`. The macros produce
+//      conditional expressions, `TerminatorKind::SwitchInt` branches, and a possible call to
+//      `begin_panic_fmt()` (that begins a panic unwind, if the assertion test fails).
+//   4. `TerminatoKind::Assert` is, however, also present in the MIR generated for this test
+//      (and in many other coverage tests). The `Assert` terminator is typically generated by the
+//      Rust compiler to check for runtime failures, such as numeric overflows.
diff --git a/tests/run-make/coverage/async.rs b/tests/run-make/coverage/async.rs
new file mode 100644
index 00000000000..efd9e62d64e
--- /dev/null
+++ b/tests/run-make/coverage/async.rs
@@ -0,0 +1,128 @@
+#![allow(unused_assignments, dead_code)]
+
+// compile-flags: --edition=2018 -C opt-level=1
+
+async fn c(x: u8) -> u8 {
+    if x == 8 {
+        1
+    } else {
+        0
+    }
+}
+
+async fn d() -> u8 { 1 }
+
+async fn e() -> u8 { 1 } // unused function; executor does not block on `g()`
+
+async fn f() -> u8 { 1 }
+
+async fn foo() -> [bool; 10] { [false; 10] } // unused function; executor does not block on `h()`
+
+pub async fn g(x: u8) {
+    match x {
+        y if e().await == y => (),
+        y if f().await == y => (),
+        _ => (),
+    }
+}
+
+async fn h(x: usize) { // The function signature is counted when called, but the body is not
+                       // executed (not awaited) so the open brace has a `0` count (at least when
+                       // displayed with `llvm-cov show` in color-mode).
+    match x {
+        y if foo().await[y] => (),
+        _ => (),
+    }
+}
+
+async fn i(x: u8) { // line coverage is 1, but there are 2 regions:
+                    // (a) the function signature, counted when the function is called; and
+                    // (b) the open brace for the function body, counted once when the body is
+                    // executed asynchronously.
+    match x {
+        y if c(x).await == y + 1 => { d().await; }
+        y if f().await == y + 1 => (),
+        _ => (),
+    }
+}
+
+fn j(x: u8) {
+    // non-async versions of `c()`, `d()`, and `f()` to make it similar to async `i()`.
+    fn c(x: u8) -> u8 {
+        if x == 8 {
+            1 // This line appears covered, but the 1-character expression span covering the `1`
+              // is not executed. (`llvm-cov show` displays a `^0` below the `1` ). This is because
+              // `fn j()` executes the open brace for the function body, followed by the function's
+              // first executable statement, `match x`. Inner function declarations are not
+              // "visible" to the MIR for `j()`, so the code region counts all lines between the
+              // open brace and the first statement as executed, which is, in a sense, true.
+              // `llvm-cov show` overcomes this kind of situation by showing the actual counts
+              // of the enclosed coverages, (that is, the `1` expression was not executed, and
+              // accurately displays a `0`).
+        } else {
+            0
+        }
+    }
+    fn d() -> u8 { 1 } // inner function is defined in-line, but the function is not executed
+    fn f() -> u8 { 1 }
+    match x {
+        y if c(x) == y + 1 => { d(); }
+        y if f() == y + 1 => (),
+        _ => (),
+    }
+}
+
+fn k(x: u8) { // unused function
+    match x {
+        1 => (),
+        2 => (),
+        _ => (),
+    }
+}
+
+fn l(x: u8) {
+    match x {
+        1 => (),
+        2 => (),
+        _ => (),
+    }
+}
+
+async fn m(x: u8) -> u8 { x - 1 }
+
+fn main() {
+    let _ = g(10);
+    let _ = h(9);
+    let mut future = Box::pin(i(8));
+    j(7);
+    l(6);
+    let _ = m(5);
+    executor::block_on(future.as_mut());
+}
+
+mod executor {
+    use core::{
+        future::Future,
+        pin::Pin,
+        task::{Context, Poll, RawWaker, RawWakerVTable, Waker},
+    };
+
+    pub fn block_on<F: Future>(mut future: F) -> F::Output {
+        let mut future = unsafe { Pin::new_unchecked(&mut future) };
+        use std::hint::unreachable_unchecked;
+        static VTABLE: RawWakerVTable = RawWakerVTable::new(
+            |_| unsafe { unreachable_unchecked() }, // clone
+            |_| unsafe { unreachable_unchecked() }, // wake
+            |_| unsafe { unreachable_unchecked() }, // wake_by_ref
+            |_| (),
+        );
+        let waker = unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &VTABLE)) };
+        let mut context = Context::from_waker(&waker);
+
+        loop {
+            if let Poll::Ready(val) = future.as_mut().poll(&mut context) {
+                break val;
+            }
+        }
+    }
+}
diff --git a/tests/run-make/coverage/async2.rs b/tests/run-make/coverage/async2.rs
new file mode 100644
index 00000000000..959d48ce9db
--- /dev/null
+++ b/tests/run-make/coverage/async2.rs
@@ -0,0 +1,69 @@
+// compile-flags: --edition=2018
+
+use core::{
+    future::Future,
+    marker::Send,
+    pin::Pin,
+};
+
+fn non_async_func() {
+    println!("non_async_func was covered");
+    let b = true;
+    if b {
+        println!("non_async_func println in block");
+    }
+}
+
+
+
+
+async fn async_func() {
+    println!("async_func was covered");
+    let b = true;
+    if b {
+        println!("async_func println in block");
+    }
+}
+
+
+
+
+async fn async_func_just_println() {
+    println!("async_func_just_println was covered");
+}
+
+fn main() {
+    println!("codecovsample::main");
+
+    non_async_func();
+
+    executor::block_on(async_func());
+    executor::block_on(async_func_just_println());
+}
+
+mod executor {
+    use core::{
+        future::Future,
+        pin::Pin,
+        task::{Context, Poll, RawWaker, RawWakerVTable, Waker},
+    };
+
+    pub fn block_on<F: Future>(mut future: F) -> F::Output {
+        let mut future = unsafe { Pin::new_unchecked(&mut future) };
+        use std::hint::unreachable_unchecked;
+        static VTABLE: RawWakerVTable = RawWakerVTable::new(
+            |_| unsafe { unreachable_unchecked() }, // clone
+            |_| unsafe { unreachable_unchecked() }, // wake
+            |_| unsafe { unreachable_unchecked() }, // wake_by_ref
+            |_| (),
+        );
+        let waker = unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &VTABLE)) };
+        let mut context = Context::from_waker(&waker);
+
+        loop {
+            if let Poll::Ready(val) = future.as_mut().poll(&mut context) {
+                break val;
+            }
+        }
+    }
+}
diff --git a/tests/run-make/coverage/closure.rs b/tests/run-make/coverage/closure.rs
new file mode 100644
index 00000000000..32ec0bcdf8c
--- /dev/null
+++ b/tests/run-make/coverage/closure.rs
@@ -0,0 +1,215 @@
+#![allow(unused_assignments, unused_variables)]
+// compile-flags: -C opt-level=2 # fix described in rustc_middle/mir/mono.rs
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+    let is_false = ! is_true;
+
+    let mut some_string = Some(String::from("the string content"));
+    println!(
+        "The string or alt: {}"
+        ,
+        some_string
+            .
+            unwrap_or_else
+        (
+            ||
+            {
+                let mut countdown = 0;
+                if is_false {
+                    countdown = 10;
+                }
+                "alt string 1".to_owned()
+            }
+        )
+    );
+
+    some_string = Some(String::from("the string content"));
+    let
+        a
+    =
+        ||
+    {
+        let mut countdown = 0;
+        if is_false {
+            countdown = 10;
+        }
+        "alt string 2".to_owned()
+    };
+    println!(
+        "The string or alt: {}"
+        ,
+        some_string
+            .
+            unwrap_or_else
+        (
+            a
+        )
+    );
+
+    some_string = None;
+    println!(
+        "The string or alt: {}"
+        ,
+        some_string
+            .
+            unwrap_or_else
+        (
+            ||
+            {
+                let mut countdown = 0;
+                if is_false {
+                    countdown = 10;
+                }
+                "alt string 3".to_owned()
+            }
+        )
+    );
+
+    some_string = None;
+    let
+        a
+    =
+        ||
+    {
+        let mut countdown = 0;
+        if is_false {
+            countdown = 10;
+        }
+        "alt string 4".to_owned()
+    };
+    println!(
+        "The string or alt: {}"
+        ,
+        some_string
+            .
+            unwrap_or_else
+        (
+            a
+        )
+    );
+
+    let
+        quote_closure
+    =
+        |val|
+    {
+        let mut countdown = 0;
+        if is_false {
+            countdown = 10;
+        }
+        format!("'{}'", val)
+    };
+    println!(
+        "Repeated, quoted string: {:?}"
+        ,
+        std::iter::repeat("repeat me")
+            .take(5)
+            .map
+        (
+            quote_closure
+        )
+            .collect::<Vec<_>>()
+    );
+
+    let
+        _unused_closure
+    =
+        |
+            mut countdown
+        |
+    {
+        if is_false {
+            countdown = 10;
+        }
+        "closure should be unused".to_owned()
+    };
+
+    let mut countdown = 10;
+    let _short_unused_closure = | _unused_arg: u8 | countdown += 1;
+
+
+    let short_used_covered_closure_macro = | used_arg: u8 | println!("called");
+    let short_used_not_covered_closure_macro = | used_arg: u8 | println!("not called");
+    let _short_unused_closure_macro = | _unused_arg: u8 | println!("not called");
+
+
+
+
+    let _short_unused_closure_block = | _unused_arg: u8 | { println!("not called") };
+
+    let _shortish_unused_closure = | _unused_arg: u8 | {
+        println!("not called")
+    };
+
+    let _as_short_unused_closure = |
+        _unused_arg: u8
+    | { println!("not called") };
+
+    let _almost_as_short_unused_closure = |
+        _unused_arg: u8
+    | { println!("not called") }
+    ;
+
+
+
+
+
+    let _short_unused_closure_line_break_no_block = | _unused_arg: u8 |
+println!("not called")
+    ;
+
+    let _short_unused_closure_line_break_no_block2 =
+        | _unused_arg: u8 |
+            println!(
+                "not called"
+            )
+    ;
+
+    let short_used_not_covered_closure_line_break_no_block_embedded_branch =
+        | _unused_arg: u8 |
+            println!(
+                "not called: {}",
+                if is_true { "check" } else { "me" }
+            )
+    ;
+
+    let short_used_not_covered_closure_line_break_block_embedded_branch =
+        | _unused_arg: u8 |
+        {
+            println!(
+                "not called: {}",
+                if is_true { "check" } else { "me" }
+            )
+        }
+    ;
+
+    let short_used_covered_closure_line_break_no_block_embedded_branch =
+        | _unused_arg: u8 |
+            println!(
+                "not called: {}",
+                if is_true { "check" } else { "me" }
+            )
+    ;
+
+    let short_used_covered_closure_line_break_block_embedded_branch =
+        | _unused_arg: u8 |
+        {
+            println!(
+                "not called: {}",
+                if is_true { "check" } else { "me" }
+            )
+        }
+    ;
+
+    if is_false {
+        short_used_not_covered_closure_macro(0);
+        short_used_not_covered_closure_line_break_no_block_embedded_branch(0);
+        short_used_not_covered_closure_line_break_block_embedded_branch(0);
+    }
+    short_used_covered_closure_macro(0);
+    short_used_covered_closure_line_break_no_block_embedded_branch(0);
+    short_used_covered_closure_line_break_block_embedded_branch(0);
+}
diff --git a/tests/run-make/coverage/closure_macro.rs b/tests/run-make/coverage/closure_macro.rs
new file mode 100644
index 00000000000..5e3b00d1ef5
--- /dev/null
+++ b/tests/run-make/coverage/closure_macro.rs
@@ -0,0 +1,40 @@
+// compile-flags: --edition=2018
+#![feature(no_coverage)]
+
+macro_rules! bail {
+    ($msg:literal $(,)?) => {
+        if $msg.len() > 0 {
+            println!("no msg");
+        } else {
+            println!($msg);
+        }
+        return Err(String::from($msg));
+    };
+}
+
+macro_rules! on_error {
+    ($value:expr, $error_message:expr) => {
+        $value.or_else(|e| { // FIXME(85000): no coverage in closure macros
+            let message = format!($error_message, e);
+            if message.len() > 0 {
+                println!("{}", message);
+                Ok(String::from("ok"))
+            } else {
+                bail!("error");
+            }
+        })
+    };
+}
+
+fn load_configuration_files() -> Result<String, String> {
+    Ok(String::from("config"))
+}
+
+pub fn main() -> Result<(), String> {
+    println!("Starting service");
+    let config = on_error!(load_configuration_files(), "Error loading configs: {}")?;
+
+    let startup_delay_duration = String::from("arg");
+    let _ = (config, startup_delay_duration);
+    Ok(())
+}
diff --git a/tests/run-make/coverage/closure_macro_async.rs b/tests/run-make/coverage/closure_macro_async.rs
new file mode 100644
index 00000000000..e3e89e9c8b3
--- /dev/null
+++ b/tests/run-make/coverage/closure_macro_async.rs
@@ -0,0 +1,81 @@
+// compile-flags: --edition=2018
+#![feature(no_coverage)]
+
+macro_rules! bail {
+    ($msg:literal $(,)?) => {
+        if $msg.len() > 0 {
+            println!("no msg");
+        } else {
+            println!($msg);
+        }
+        return Err(String::from($msg));
+    };
+}
+
+macro_rules! on_error {
+    ($value:expr, $error_message:expr) => {
+        $value.or_else(|e| { // FIXME(85000): no coverage in closure macros
+            let message = format!($error_message, e);
+            if message.len() > 0 {
+                println!("{}", message);
+                Ok(String::from("ok"))
+            } else {
+                bail!("error");
+            }
+        })
+    };
+}
+
+fn load_configuration_files() -> Result<String, String> {
+    Ok(String::from("config"))
+}
+
+pub async fn test() -> Result<(), String> {
+    println!("Starting service");
+    let config = on_error!(load_configuration_files(), "Error loading configs: {}")?;
+
+    let startup_delay_duration = String::from("arg");
+    let _ = (config, startup_delay_duration);
+    Ok(())
+}
+
+#[no_coverage]
+fn main() {
+    executor::block_on(test());
+}
+
+mod executor {
+    use core::{
+        future::Future,
+        pin::Pin,
+        task::{Context, Poll, RawWaker, RawWakerVTable, Waker},
+    };
+
+    #[no_coverage]
+    pub fn block_on<F: Future>(mut future: F) -> F::Output {
+        let mut future = unsafe { Pin::new_unchecked(&mut future) };
+        use std::hint::unreachable_unchecked;
+        static VTABLE: RawWakerVTable = RawWakerVTable::new(
+
+            #[no_coverage]
+            |_| unsafe { unreachable_unchecked() }, // clone
+
+            #[no_coverage]
+            |_| unsafe { unreachable_unchecked() }, // wake
+
+            #[no_coverage]
+            |_| unsafe { unreachable_unchecked() }, // wake_by_ref
+
+            #[no_coverage]
+            |_| (),
+        );
+        let waker = unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &VTABLE)) };
+        let mut context = Context::from_waker(&waker);
+
+        loop {
+            if let Poll::Ready(val) = future.as_mut().poll(&mut context) {
+                break val;
+            }
+        }
+    }
+}
diff --git a/tests/run-make/coverage/compiletest-ignore-dir b/tests/run-make/coverage/compiletest-ignore-dir
new file mode 100644
index 00000000000..b533b272d38
--- /dev/null
+++ b/tests/run-make/coverage/compiletest-ignore-dir
@@ -0,0 +1,3 @@
+# Directory "coverage" supports the tests at prefix ../coverage-*
+
+# Use ./x.py [options] test src/test/run-make/coverage to run all related tests.
diff --git a/tests/run-make/coverage/conditions.rs b/tests/run-make/coverage/conditions.rs
new file mode 100644
index 00000000000..057599d1b47
--- /dev/null
+++ b/tests/run-make/coverage/conditions.rs
@@ -0,0 +1,87 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    let mut countdown = 0;
+    if true {
+        countdown = 10;
+    }
+
+    const B: u32 = 100;
+    let x = if countdown > 7 {
+        countdown -= 4;
+        B
+    } else if countdown > 2 {
+        if countdown < 1 || countdown > 5 || countdown != 9 {
+            countdown = 0;
+        }
+        countdown -= 5;
+        countdown
+    } else {
+        return;
+    };
+
+    let mut countdown = 0;
+    if true {
+        countdown = 10;
+    }
+
+    if countdown > 7 {
+        countdown -= 4;
+    } else if countdown > 2 {
+        if countdown < 1 || countdown > 5 || countdown != 9 {
+            countdown = 0;
+        }
+        countdown -= 5;
+    } else {
+        return;
+    }
+
+    if true {
+        let mut countdown = 0;
+        if true {
+            countdown = 10;
+        }
+
+        if countdown > 7 {
+            countdown -= 4;
+        }
+        else if countdown > 2 {
+            if countdown < 1 || countdown > 5 || countdown != 9 {
+                countdown = 0;
+            }
+            countdown -= 5;
+        } else {
+            return;
+        }
+    }
+
+
+    let mut countdown = 0;
+    if true {
+        countdown = 1;
+    }
+
+    let z = if countdown > 7 {
+        countdown -= 4;
+    } else if countdown > 2 {
+        if countdown < 1 || countdown > 5 || countdown != 9 {
+            countdown = 0;
+        }
+        countdown -= 5;
+    } else {
+        let should_be_reachable = countdown;
+        println!("reached");
+        return;
+    };
+
+    let w = if countdown > 7 {
+        countdown -= 4;
+    } else if countdown > 2 {
+        if countdown < 1 || countdown > 5 || countdown != 9 {
+            countdown = 0;
+        }
+        countdown -= 5;
+    } else {
+        return;
+    };
+}
diff --git a/tests/run-make/coverage/continue.rs b/tests/run-make/coverage/continue.rs
new file mode 100644
index 00000000000..624aa98341b
--- /dev/null
+++ b/tests/run-make/coverage/continue.rs
@@ -0,0 +1,69 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    let is_true = std::env::args().len() == 1;
+
+    let mut x = 0;
+    for _ in 0..10 {
+        match is_true {
+            true => {
+                continue;
+            }
+            _ => {
+                x = 1;
+            }
+        }
+        x = 3;
+    }
+    for _ in 0..10 {
+        match is_true {
+            false => {
+                x = 1;
+            }
+            _ => {
+                continue;
+            }
+        }
+        x = 3;
+    }
+    for _ in 0..10 {
+        match is_true {
+            true => {
+                x = 1;
+            }
+            _ => {
+                continue;
+            }
+        }
+        x = 3;
+    }
+    for _ in 0..10 {
+        if is_true {
+            continue;
+        }
+        x = 3;
+    }
+    for _ in 0..10 {
+        match is_true {
+            false => {
+                x = 1;
+            }
+            _ => {
+                let _ = x;
+            }
+        }
+        x = 3;
+    }
+    for _ in 0..10 {
+        match is_true {
+            false => {
+                x = 1;
+            }
+            _ => {
+                break;
+            }
+        }
+        x = 3;
+    }
+    let _ = x;
+}
diff --git a/tests/run-make/coverage/coverage_tools.mk b/tests/run-make/coverage/coverage_tools.mk
new file mode 100644
index 00000000000..0b6bbc33167
--- /dev/null
+++ b/tests/run-make/coverage/coverage_tools.mk
@@ -0,0 +1,6 @@
+# Common Makefile include for Rust `run-make/coverage-* tests. Include this
+# file with the line:
+#
+# include ../coverage/coverage_tools.mk
+
+include ../../run-make-fulldeps/tools.mk
diff --git a/tests/run-make/coverage/dead_code.rs b/tests/run-make/coverage/dead_code.rs
new file mode 100644
index 00000000000..a1285df0ec6
--- /dev/null
+++ b/tests/run-make/coverage/dead_code.rs
@@ -0,0 +1,37 @@
+#![allow(unused_assignments, unused_variables)]
+
+pub fn unused_pub_fn_not_in_library() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+}
+
+fn unused_fn() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+}
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+}
diff --git a/tests/run-make/coverage/doctest.rs b/tests/run-make/coverage/doctest.rs
new file mode 100644
index 00000000000..ec04ea57063
--- /dev/null
+++ b/tests/run-make/coverage/doctest.rs
@@ -0,0 +1,99 @@
+//! This test ensures that code from doctests is properly re-mapped.
+//! See <https://github.com/rust-lang/rust/issues/79417> for more info.
+//!
+//! Just some random code:
+//! ```
+//! if true {
+//!     // this is executed!
+//!     assert_eq!(1, 1);
+//! } else {
+//!     // this is not!
+//!     assert_eq!(1, 2);
+//! }
+//! ```
+//!
+//! doctest testing external code:
+//! ```
+//! extern crate doctest_crate;
+//! doctest_crate::fn_run_in_doctests(1);
+//! ```
+//!
+//! doctest returning a result:
+//! ```
+//! #[derive(Debug, PartialEq)]
+//! struct SomeError {
+//!     msg: String,
+//! }
+//! let mut res = Err(SomeError { msg: String::from("a message") });
+//! if res.is_ok() {
+//!     res?;
+//! } else {
+//!     if *res.as_ref().unwrap_err() == *res.as_ref().unwrap_err() {
+//!         println!("{:?}", res);
+//!     }
+//!     if *res.as_ref().unwrap_err() == *res.as_ref().unwrap_err() {
+//!         res = Ok(1);
+//!     }
+//!     res = Ok(0);
+//! }
+//! // need to be explicit because rustdoc cant infer the return type
+//! Ok::<(), SomeError>(())
+//! ```
+//!
+//! doctest with custom main:
+//! ```
+//! fn some_func() {
+//!     println!("called some_func()");
+//! }
+//!
+//! #[derive(Debug)]
+//! struct SomeError;
+//!
+//! extern crate doctest_crate;
+//!
+//! fn doctest_main() -> Result<(), SomeError> {
+//!     some_func();
+//!     doctest_crate::fn_run_in_doctests(2);
+//!     Ok(())
+//! }
+//!
+//! // this `main` is not shown as covered, as it clashes with all the other
+//! // `main` functions that were automatically generated for doctests
+//! fn main() -> Result<(), SomeError> {
+//!     doctest_main()
+//! }
+//! ```
+
+/// doctest attached to fn testing external code:
+/// ```
+/// extern crate doctest_crate;
+/// doctest_crate::fn_run_in_doctests(3);
+/// ```
+///
+fn main() {
+    if true {
+        assert_eq!(1, 1);
+    } else {
+        assert_eq!(1, 2);
+    }
+}
+
+// FIXME(Swatinem): Fix known issue that coverage code region columns need to be offset by the
+// doc comment line prefix (`///` or `//!`) and any additional indent (before or after the doc
+// comment characters). This test produces `llvm-cov show` results demonstrating the problem.
+//
+// One of the above tests now includes: `derive(Debug, PartialEq)`, producing an `llvm-cov show`
+// result with a distinct count for `Debug`, denoted by `^1`, but the caret points to the wrong
+// column. Similarly, the `if` blocks without `else` blocks show `^0`, which should point at, or
+// one character past, the `if` block's closing brace. In both cases, these are most likely off
+// by the number of characters stripped from the beginning of each doc comment line: indent
+// whitespace, if any, doc comment prefix (`//!` in this case) and (I assume) one space character
+// (?). Note, when viewing `llvm-cov show` results in `--color` mode, the column offset errors are
+// more pronounced, and show up in more places, with background color used to show some distinct
+// code regions with different coverage counts.
+//
+// NOTE: Since the doc comment line prefix may vary, one possible solution is to replace each
+// character stripped from the beginning of doc comment lines with a space. This will give coverage
+// results the correct column offsets, and I think it should compile correctly, but I don't know
+// what affect it might have on diagnostic messages from the compiler, and whether anyone would care
+// if the indentation changed. I don't know if there is a more viable solution.
diff --git a/tests/run-make/coverage/drop_trait.rs b/tests/run-make/coverage/drop_trait.rs
new file mode 100644
index 00000000000..d15bfc0f877
--- /dev/null
+++ b/tests/run-make/coverage/drop_trait.rs
@@ -0,0 +1,33 @@
+#![allow(unused_assignments)]
+// expect-exit-status-1
+
+struct Firework {
+    strength: i32,
+}
+
+impl Drop for Firework {
+    fn drop(&mut self) {
+        println!("BOOM times {}!!!", self.strength);
+    }
+}
+
+fn main() -> Result<(),u8> {
+    let _firecracker = Firework { strength: 1 };
+
+    let _tnt = Firework { strength: 100 };
+
+    if true {
+        println!("Exiting with error...");
+        return Err(1);
+    }
+
+    let _ = Firework { strength: 1000 };
+
+    Ok(())
+}
+
+// Expected program output:
+//   Exiting with error...
+//   BOOM times 100!!!
+//   BOOM times 1!!!
+//   Error: 1
diff --git a/tests/run-make/coverage/generator.rs b/tests/run-make/coverage/generator.rs
new file mode 100644
index 00000000000..4319991021e
--- /dev/null
+++ b/tests/run-make/coverage/generator.rs
@@ -0,0 +1,30 @@
+#![feature(generators, generator_trait)]
+
+use std::ops::{Generator, GeneratorState};
+use std::pin::Pin;
+
+// The following implementation of a function called from a `yield` statement
+// (apparently requiring the Result and the `String` type or constructor)
+// creates conditions where the `generator::StateTransform` MIR transform will
+// drop all `Counter` `Coverage` statements from a MIR. `simplify.rs` has logic
+// to handle this condition, and still report dead block coverage.
+fn get_u32(val: bool) -> Result<u32, String> {
+    if val { Ok(1) } else { Err(String::from("some error")) }
+}
+
+fn main() {
+    let is_true = std::env::args().len() == 1;
+    let mut generator = || {
+        yield get_u32(is_true);
+        return "foo";
+    };
+
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Yielded(Ok(1)) => {}
+        _ => panic!("unexpected return from resume"),
+    }
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Complete("foo") => {}
+        _ => panic!("unexpected return from resume"),
+    }
+}
diff --git a/tests/run-make/coverage/generics.rs b/tests/run-make/coverage/generics.rs
new file mode 100644
index 00000000000..18b38868496
--- /dev/null
+++ b/tests/run-make/coverage/generics.rs
@@ -0,0 +1,48 @@
+#![allow(unused_assignments)]
+// expect-exit-status-1
+
+struct Firework<T> where T: Copy + std::fmt::Display {
+    strength: T,
+}
+
+impl<T> Firework<T> where T: Copy + std::fmt::Display {
+    #[inline(always)]
+    fn set_strength(&mut self, new_strength: T) {
+        self.strength = new_strength;
+    }
+}
+
+impl<T> Drop for Firework<T> where T: Copy + std::fmt::Display {
+    #[inline(always)]
+    fn drop(&mut self) {
+        println!("BOOM times {}!!!", self.strength);
+    }
+}
+
+fn main() -> Result<(),u8> {
+    let mut firecracker = Firework { strength: 1 };
+    firecracker.set_strength(2);
+
+    let mut tnt = Firework { strength: 100.1 };
+    tnt.set_strength(200.1);
+    tnt.set_strength(300.3);
+
+    if true {
+        println!("Exiting with error...");
+        return Err(1);
+    }
+
+
+
+
+
+    let _ = Firework { strength: 1000 };
+
+    Ok(())
+}
+
+// Expected program output:
+//   Exiting with error...
+//   BOOM times 100!!!
+//   BOOM times 1!!!
+//   Error: 1
diff --git a/tests/run-make/coverage/if.rs b/tests/run-make/coverage/if.rs
new file mode 100644
index 00000000000..8ad5042ff7b
--- /dev/null
+++ b/tests/run-make/coverage/if.rs
@@ -0,0 +1,28 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let
+    is_true
+    =
+        std::env::args().len()
+    ==
+        1
+    ;
+    let
+        mut
+    countdown
+    =
+        0
+    ;
+    if
+        is_true
+    {
+        countdown
+        =
+            10
+        ;
+    }
+}
diff --git a/tests/run-make/coverage/if_else.rs b/tests/run-make/coverage/if_else.rs
new file mode 100644
index 00000000000..3244e1e3afd
--- /dev/null
+++ b/tests/run-make/coverage/if_else.rs
@@ -0,0 +1,40 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+    if
+        is_true
+    {
+        countdown
+        =
+            10
+        ;
+    }
+    else // Note coverage region difference without semicolon
+    {
+        countdown
+        =
+            100
+    }
+
+    if
+        is_true
+    {
+        countdown
+        =
+            10
+        ;
+    }
+    else
+    {
+        countdown
+        =
+            100
+        ;
+    }
+}
diff --git a/tests/run-make/coverage/inline-dead.rs b/tests/run-make/coverage/inline-dead.rs
new file mode 100644
index 00000000000..854fa062967
--- /dev/null
+++ b/tests/run-make/coverage/inline-dead.rs
@@ -0,0 +1,27 @@
+// Regression test for issue #98833.
+// compile-flags: -Zinline-mir -Cdebug-assertions=off
+
+fn main() {
+    println!("{}", live::<false>());
+
+    let f = |x: bool| {
+        debug_assert!(
+            x
+        );
+    };
+    f(false);
+}
+
+#[inline]
+fn live<const B: bool>() -> u32 {
+    if B {
+        dead()
+    } else {
+        0
+    }
+}
+
+#[inline]
+fn dead() -> u32 {
+    42
+}
diff --git a/tests/run-make/coverage/inline.rs b/tests/run-make/coverage/inline.rs
new file mode 100644
index 00000000000..9cfab9ddbad
--- /dev/null
+++ b/tests/run-make/coverage/inline.rs
@@ -0,0 +1,51 @@
+// compile-flags: -Zinline-mir
+
+use std::fmt::Display;
+
+fn main() {
+    permutations(&['a', 'b', 'c']);
+}
+
+#[inline(always)]
+fn permutations<T: Copy + Display>(xs: &[T]) {
+    let mut ys = xs.to_owned();
+    permutate(&mut ys, 0);
+}
+
+fn permutate<T: Copy + Display>(xs: &mut [T], k: usize) {
+    let n = length(xs);
+    if k == n {
+        display(xs);
+    } else if k < n {
+        for i in k..n {
+            swap(xs, i, k);
+            permutate(xs, k + 1);
+            swap(xs, i, k);
+        }
+    } else {
+        error();
+    }
+}
+
+fn length<T>(xs: &[T]) -> usize {
+    xs.len()
+}
+
+#[inline]
+fn swap<T: Copy>(xs: &mut [T], i: usize, j: usize) {
+    let t = xs[i];
+    xs[i] = xs[j];
+    xs[j] = t;
+}
+
+fn display<T: Display>(xs: &[T]) {
+    for x in xs {
+        print!("{}", x);
+    }
+    println!();
+}
+
+#[inline(always)]
+fn error() {
+    panic!("error");
+}
diff --git a/tests/run-make/coverage/inner_items.rs b/tests/run-make/coverage/inner_items.rs
new file mode 100644
index 00000000000..bcb62b3031c
--- /dev/null
+++ b/tests/run-make/coverage/inner_items.rs
@@ -0,0 +1,57 @@
+#![allow(unused_assignments, unused_variables, dead_code)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+
+    mod in_mod {
+        const IN_MOD_CONST: u32 = 1000;
+    }
+
+    fn in_func(a: u32) {
+        let b = 1;
+        let c = a + b;
+        println!("c = {}", c)
+    }
+
+    struct InStruct {
+        in_struct_field: u32,
+    }
+
+    const IN_CONST: u32 = 1234;
+
+    trait InTrait {
+        fn trait_func(&mut self, incr: u32);
+
+        fn default_trait_func(&mut self) {
+            in_func(IN_CONST);
+            self.trait_func(IN_CONST);
+        }
+    }
+
+    impl InTrait for InStruct {
+        fn trait_func(&mut self, incr: u32) {
+            self.in_struct_field += incr;
+            in_func(self.in_struct_field);
+        }
+    }
+
+    type InType = String;
+
+    if is_true {
+        in_func(countdown);
+    }
+
+    let mut val = InStruct {
+        in_struct_field: 101,
+    };
+
+    val.default_trait_func();
+}
diff --git a/tests/run-make/coverage/issue-83601.rs b/tests/run-make/coverage/issue-83601.rs
new file mode 100644
index 00000000000..0b72a81947c
--- /dev/null
+++ b/tests/run-make/coverage/issue-83601.rs
@@ -0,0 +1,14 @@
+// Shows that rust-lang/rust/83601 is resolved
+
+#[derive(Debug, PartialEq, Eq)]
+struct Foo(u32);
+
+fn main() {
+    let bar = Foo(1);
+    assert_eq!(bar, Foo(1));
+    let baz = Foo(0);
+    assert_ne!(baz, Foo(1));
+    println!("{:?}", Foo(1));
+    println!("{:?}", bar);
+    println!("{:?}", baz);
+}
diff --git a/tests/run-make/coverage/issue-84561.rs b/tests/run-make/coverage/issue-84561.rs
new file mode 100644
index 00000000000..b39a289c45e
--- /dev/null
+++ b/tests/run-make/coverage/issue-84561.rs
@@ -0,0 +1,182 @@
+// This demonstrated Issue #84561: function-like macros produce unintuitive coverage results.
+
+// expect-exit-status-101
+#[derive(PartialEq, Eq)]
+struct Foo(u32);
+fn test3() {
+    let is_true = std::env::args().len() == 1;
+    let bar = Foo(1);
+    assert_eq!(bar, Foo(1));
+    let baz = Foo(0);
+    assert_ne!(baz, Foo(1));
+    println!("{:?}", Foo(1));
+    println!("{:?}", bar);
+    println!("{:?}", baz);
+
+    assert_eq!(Foo(1), Foo(1));
+    assert_ne!(Foo(0), Foo(1));
+    assert_eq!(Foo(2), Foo(2));
+    let bar = Foo(0);
+    assert_ne!(bar, Foo(3));
+    assert_ne!(Foo(0), Foo(4));
+    assert_eq!(Foo(3), Foo(3), "with a message");
+    println!("{:?}", bar);
+    println!("{:?}", Foo(1));
+
+    assert_ne!(Foo(0), Foo(5), "{}", if is_true { "true message" } else { "false message" });
+    assert_ne!(
+        Foo(0)
+        ,
+        Foo(5)
+        ,
+        "{}"
+        ,
+        if
+        is_true
+        {
+            "true message"
+        } else {
+            "false message"
+        }
+    );
+
+    let is_true = std::env::args().len() == 1;
+
+    assert_eq!(
+        Foo(1),
+        Foo(1)
+    );
+    assert_ne!(
+        Foo(0),
+        Foo(1)
+    );
+    assert_eq!(
+        Foo(2),
+        Foo(2)
+    );
+    let bar = Foo(1);
+    assert_ne!(
+        bar,
+        Foo(3)
+    );
+    if is_true {
+        assert_ne!(
+            Foo(0),
+            Foo(4)
+        );
+    } else {
+        assert_eq!(
+            Foo(3),
+            Foo(3)
+        );
+    }
+    if is_true {
+        assert_ne!(
+            Foo(0),
+            Foo(4),
+            "with a message"
+        );
+    } else {
+        assert_eq!(
+            Foo(3),
+            Foo(3),
+            "with a message"
+        );
+    }
+    assert_ne!(
+        if is_true {
+            Foo(0)
+        } else {
+            Foo(1)
+        },
+        Foo(5)
+    );
+    assert_ne!(
+        Foo(5),
+        if is_true {
+            Foo(0)
+        } else {
+            Foo(1)
+        }
+    );
+    assert_ne!(
+        if is_true {
+            assert_eq!(
+                Foo(3),
+                Foo(3)
+            );
+            Foo(0)
+        } else {
+            assert_ne!(
+                if is_true {
+                    Foo(0)
+                } else {
+                    Foo(1)
+                },
+                Foo(5)
+            );
+            Foo(1)
+        },
+        Foo(5),
+        "with a message"
+    );
+    assert_eq!(
+        Foo(1),
+        Foo(3),
+        "this assert should fail"
+    );
+    assert_eq!(
+        Foo(3),
+        Foo(3),
+        "this assert should not be reached"
+    );
+}
+
+impl std::fmt::Debug for Foo {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "try and succeed")?;
+        Ok(())
+    }
+}
+
+static mut DEBUG_LEVEL_ENABLED: bool = false;
+
+macro_rules! debug {
+    ($($arg:tt)+) => (
+        if unsafe { DEBUG_LEVEL_ENABLED } {
+            println!($($arg)+);
+        }
+    );
+}
+
+fn test1() {
+    debug!("debug is enabled");
+    debug!("debug is enabled");
+    let _ = 0;
+    debug!("debug is enabled");
+    unsafe {
+        DEBUG_LEVEL_ENABLED = true;
+    }
+    debug!("debug is enabled");
+}
+
+macro_rules! call_debug {
+    ($($arg:tt)+) => (
+        fn call_print(s: &str) {
+            print!("{}", s);
+        }
+
+        call_print("called from call_debug: ");
+        debug!($($arg)+);
+    );
+}
+
+fn test2() {
+    call_debug!("debug is enabled");
+}
+
+fn main() {
+    test1();
+    test2();
+    test3();
+}
diff --git a/tests/run-make/coverage/issue-85461.rs b/tests/run-make/coverage/issue-85461.rs
new file mode 100644
index 00000000000..a1b9ebb1ed3
--- /dev/null
+++ b/tests/run-make/coverage/issue-85461.rs
@@ -0,0 +1,10 @@
+// Regression test for #85461: MSVC sometimes fail to link with dead code and #[inline(always)]
+
+extern crate inline_always_with_dead_code;
+
+use inline_always_with_dead_code::{bar, baz};
+
+fn main() {
+    bar::call_me();
+    baz::call_me();
+}
diff --git a/tests/run-make/coverage/issue-93054.rs b/tests/run-make/coverage/issue-93054.rs
new file mode 100644
index 00000000000..c160b3db03f
--- /dev/null
+++ b/tests/run-make/coverage/issue-93054.rs
@@ -0,0 +1,28 @@
+// Regression test for #93054: Functions using uninhabited types often only have a single,
+// unreachable basic block which doesn't get instrumented. This should not cause llvm-cov to fail.
+// Since these kinds functions can't be invoked anyway, it's ok to not have coverage data for them.
+
+// compile-flags: --edition=2021
+
+enum Never { }
+
+impl Never {
+    fn foo(self) {
+        match self { }
+        make().map(|never| match never { });
+    }
+
+    fn bar(&self) {
+        match *self { }
+    }
+}
+
+async fn foo2(never: Never) {
+    match never { }
+}
+
+fn make() -> Option<Never> {
+    None
+}
+
+fn main() { }
diff --git a/tests/run-make/coverage/lazy_boolean.rs b/tests/run-make/coverage/lazy_boolean.rs
new file mode 100644
index 00000000000..bb6219e851c
--- /dev/null
+++ b/tests/run-make/coverage/lazy_boolean.rs
@@ -0,0 +1,61 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let (mut a, mut b, mut c) = (0, 0, 0);
+    if is_true {
+        a = 1;
+        b = 10;
+        c = 100;
+    }
+    let
+        somebool
+        =
+            a < b
+        ||
+            b < c
+    ;
+    let
+        somebool
+        =
+            b < a
+        ||
+            b < c
+    ;
+    let somebool = a < b && b < c;
+    let somebool = b < a && b < c;
+
+    if
+        !
+        is_true
+    {
+        a = 2
+        ;
+    }
+
+    if
+        is_true
+    {
+        b = 30
+        ;
+    }
+    else
+    {
+        c = 400
+        ;
+    }
+
+    if !is_true {
+        a = 2;
+    }
+
+    if is_true {
+        b = 30;
+    } else {
+        c = 400;
+    }
+}
diff --git a/tests/run-make/coverage/lib/doctest_crate.rs b/tests/run-make/coverage/lib/doctest_crate.rs
new file mode 100644
index 00000000000..c3210146d69
--- /dev/null
+++ b/tests/run-make/coverage/lib/doctest_crate.rs
@@ -0,0 +1,9 @@
+/// A function run only from within doctests
+pub fn fn_run_in_doctests(conditional: usize) {
+    match conditional {
+        1 => assert_eq!(1, 1), // this is run,
+        2 => assert_eq!(1, 1), // this,
+        3 => assert_eq!(1, 1), // and this too
+        _ => assert_eq!(1, 2), // however this is not
+    }
+}
diff --git a/tests/run-make/coverage/lib/inline_always_with_dead_code.rs b/tests/run-make/coverage/lib/inline_always_with_dead_code.rs
new file mode 100644
index 00000000000..2b21dee6ccf
--- /dev/null
+++ b/tests/run-make/coverage/lib/inline_always_with_dead_code.rs
@@ -0,0 +1,22 @@
+// compile-flags: -Cinstrument-coverage -Ccodegen-units=4 -Copt-level=0
+
+#![allow(dead_code)]
+
+mod foo {
+    #[inline(always)]
+    pub fn called() { }
+
+    fn uncalled() { }
+}
+
+pub mod bar {
+    pub fn call_me() {
+        super::foo::called();
+    }
+}
+
+pub mod baz {
+    pub fn call_me() {
+        super::foo::called();
+    }
+}
diff --git a/tests/run-make/coverage/lib/unused_mod_helper.rs b/tests/run-make/coverage/lib/unused_mod_helper.rs
new file mode 100644
index 00000000000..ae1cc1531ed
--- /dev/null
+++ b/tests/run-make/coverage/lib/unused_mod_helper.rs
@@ -0,0 +1,3 @@
+pub fn never_called_function() {
+    println!("I am never called");
+}
diff --git a/tests/run-make/coverage/lib/used_crate.rs b/tests/run-make/coverage/lib/used_crate.rs
new file mode 100644
index 00000000000..8b8b1f7f351
--- /dev/null
+++ b/tests/run-make/coverage/lib/used_crate.rs
@@ -0,0 +1,100 @@
+#![allow(unused_assignments, unused_variables)]
+// compile-flags: -C opt-level=3 # validates coverage now works with optimizations
+use std::fmt::Debug;
+
+pub fn used_function() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+    use_this_lib_crate();
+}
+
+pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_only_from_bin_crate_generic_function with {:?}", arg);
+}
+// Expect for above function: `Unexecuted instantiation` (see below)
+pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
+}
+
+pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
+}
+
+pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
+}
+
+pub fn unused_generic_function<T: Debug>(arg: T) {
+    println!("unused_generic_function with {:?}", arg);
+}
+
+pub fn unused_function() {
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 2;
+    if !is_true {
+        countdown = 20;
+    }
+}
+
+fn unused_private_function() {
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 2;
+    if !is_true {
+        countdown = 20;
+    }
+}
+
+fn use_this_lib_crate() {
+    used_from_bin_crate_and_lib_crate_generic_function("used from library used_crate.rs");
+    used_with_same_type_from_bin_crate_and_lib_crate_generic_function(
+        "used from library used_crate.rs",
+    );
+    let some_vec = vec![5, 6, 7, 8];
+    used_only_from_this_lib_crate_generic_function(some_vec);
+    used_only_from_this_lib_crate_generic_function("used ONLY from library used_crate.rs");
+}
+
+// FIXME(#79651): "Unexecuted instantiation" errors appear in coverage results,
+// for example:
+//
+// | Unexecuted instantiation: used_crate::used_only_from_bin_crate_generic_function::<_>
+//
+// These notices appear when `llvm-cov` shows instantiations. This may be a
+// default option, but it can be suppressed with:
+//
+// ```shell
+// $ `llvm-cov show --show-instantiations=0 ...`
+// ```
+//
+// The notice is triggered because the function is unused by the library itself,
+// and when the library is compiled, a synthetic function is generated, so
+// unused function coverage can be reported. Coverage can be skipped for unused
+// generic functions with:
+//
+// ```shell
+// $ `rustc -Zunstable-options -C instrument-coverage=except-unused-generics ...`
+// ```
+//
+// Even though this function is used by `uses_crate.rs` (and
+// counted), with substitutions for `T`, those instantiations are only generated
+// when the generic function is actually used (from the binary, not from this
+// library crate). So the test result shows coverage for all instantiated
+// versions and their generic type substitutions, plus the `Unexecuted
+// instantiation` message for the non-substituted version. This is valid, but
+// unfortunately a little confusing.
+//
+// The library crate has its own coverage map, and the only way to show unused
+// coverage of a generic function is to include the generic function in the
+// coverage map, marked as an "unused function". If the library were used by
+// another binary that never used this generic function, then it would be valid
+// to show the unused generic, with unknown substitution (`_`).
+//
+// The alternative is to exclude all generics from being included in the "unused
+// functions" list, which would then omit coverage results for
+// `unused_generic_function<T>()`, below.
diff --git a/tests/run-make/coverage/lib/used_inline_crate.rs b/tests/run-make/coverage/lib/used_inline_crate.rs
new file mode 100644
index 00000000000..4a052756d4e
--- /dev/null
+++ b/tests/run-make/coverage/lib/used_inline_crate.rs
@@ -0,0 +1,90 @@
+#![allow(unused_assignments, unused_variables)]
+
+// compile-flags: -C opt-level=3 # validates coverage now works with optimizations
+
+use std::fmt::Debug;
+
+pub fn used_function() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+    use_this_lib_crate();
+}
+
+#[inline(always)]
+pub fn used_inline_function() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 0;
+    if is_true {
+        countdown = 10;
+    }
+    use_this_lib_crate();
+}
+
+
+
+
+
+
+
+#[inline(always)]
+pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_only_from_bin_crate_generic_function with {:?}", arg);
+}
+// Expect for above function: `Unexecuted instantiation` (see notes in `used_crate.rs`)
+
+#[inline(always)]
+pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
+}
+
+#[inline(always)]
+pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
+}
+
+#[inline(always)]
+pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
+    println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
+}
+
+#[inline(always)]
+pub fn unused_generic_function<T: Debug>(arg: T) {
+    println!("unused_generic_function with {:?}", arg);
+}
+
+#[inline(always)]
+pub fn unused_function() {
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 2;
+    if !is_true {
+        countdown = 20;
+    }
+}
+
+#[inline(always)]
+fn unused_private_function() {
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 2;
+    if !is_true {
+        countdown = 20;
+    }
+}
+
+fn use_this_lib_crate() {
+    used_from_bin_crate_and_lib_crate_generic_function("used from library used_crate.rs");
+    used_with_same_type_from_bin_crate_and_lib_crate_generic_function(
+        "used from library used_crate.rs",
+    );
+    let some_vec = vec![5, 6, 7, 8];
+    used_only_from_this_lib_crate_generic_function(some_vec);
+    used_only_from_this_lib_crate_generic_function("used ONLY from library used_crate.rs");
+}
diff --git a/tests/run-make/coverage/loop_break_value.rs b/tests/run-make/coverage/loop_break_value.rs
new file mode 100644
index 00000000000..dbc4fad7a23
--- /dev/null
+++ b/tests/run-make/coverage/loop_break_value.rs
@@ -0,0 +1,13 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    let result
+        =
+            loop
+        {
+            break
+            10
+            ;
+        }
+    ;
+}
diff --git a/tests/run-make/coverage/loops_branches.rs b/tests/run-make/coverage/loops_branches.rs
new file mode 100644
index 00000000000..7116ce47f4b
--- /dev/null
+++ b/tests/run-make/coverage/loops_branches.rs
@@ -0,0 +1,61 @@
+#![allow(unused_assignments, unused_variables, while_true)]
+
+// This test confirms that (1) unexecuted infinite loops are handled correctly by the
+// InstrumentCoverage MIR pass; and (2) Counter Expressions that subtract from zero can be dropped.
+
+struct DebugTest;
+
+impl std::fmt::Debug for DebugTest {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        if true {
+            if false {
+                while true {
+                }
+            }
+            write!(f, "cool")?;
+        } else {
+        }
+
+        for i in 0..10 {
+            if true {
+                if false {
+                    while true {}
+                }
+                write!(f, "cool")?;
+            } else {
+            }
+        }
+        Ok(())
+    }
+}
+
+struct DisplayTest;
+
+impl std::fmt::Display for DisplayTest {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        if false {
+        } else {
+            if false {
+                while true {}
+            }
+            write!(f, "cool")?;
+        }
+        for i in 0..10 {
+            if false {
+            } else {
+                if false {
+                    while true {}
+                }
+                write!(f, "cool")?;
+            }
+        }
+        Ok(())
+    }
+}
+
+fn main() {
+    let debug_test = DebugTest;
+    println!("{:?}", debug_test);
+    let display_test = DisplayTest;
+    println!("{}", display_test);
+}
diff --git a/tests/run-make/coverage/match_or_pattern.rs b/tests/run-make/coverage/match_or_pattern.rs
new file mode 100644
index 00000000000..4c6a8a9b703
--- /dev/null
+++ b/tests/run-make/coverage/match_or_pattern.rs
@@ -0,0 +1,45 @@
+#![feature(or_patterns)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut a: u8 = 0;
+    let mut b: u8 = 0;
+    if is_true {
+        a = 2;
+        b = 0;
+    }
+    match (a, b) {
+        // Or patterns generate MIR `SwitchInt` with multiple targets to the same `BasicBlock`.
+        // This test confirms a fix for Issue #79569.
+        (0 | 1, 2 | 3) => {}
+        _ => {}
+    }
+    if is_true {
+        a = 0;
+        b = 0;
+    }
+    match (a, b) {
+        (0 | 1, 2 | 3) => {}
+        _ => {}
+    }
+    if is_true {
+        a = 2;
+        b = 2;
+    }
+    match (a, b) {
+        (0 | 1, 2 | 3) => {}
+        _ => {}
+    }
+    if is_true {
+        a = 0;
+        b = 2;
+    }
+    match (a, b) {
+        (0 | 1, 2 | 3) => {}
+        _ => {}
+    }
+}
diff --git a/tests/run-make/coverage/nested_loops.rs b/tests/run-make/coverage/nested_loops.rs
new file mode 100644
index 00000000000..4c7c7842796
--- /dev/null
+++ b/tests/run-make/coverage/nested_loops.rs
@@ -0,0 +1,25 @@
+fn main() {
+    let is_true = std::env::args().len() == 1;
+    let mut countdown = 10;
+
+    'outer: while countdown > 0 {
+        let mut a = 100;
+        let mut b = 100;
+        for _ in 0..50 {
+            if a < 30 {
+                break;
+            }
+            a -= 5;
+            b -= 5;
+            if b < 90 {
+                a -= 10;
+                if is_true {
+                    break 'outer;
+                } else {
+                    a -= 2;
+                }
+            }
+        }
+        countdown -= 1;
+    }
+}
diff --git a/tests/run-make/coverage/no_cov_crate.rs b/tests/run-make/coverage/no_cov_crate.rs
new file mode 100644
index 00000000000..0bfbdda2cab
--- /dev/null
+++ b/tests/run-make/coverage/no_cov_crate.rs
@@ -0,0 +1,86 @@
+// Enables `no_coverage` on the entire crate
+#![feature(no_coverage)]
+
+#[no_coverage]
+fn do_not_add_coverage_1() {
+    println!("called but not covered");
+}
+
+fn do_not_add_coverage_2() {
+    #![no_coverage]
+    println!("called but not covered");
+}
+
+#[no_coverage]
+fn do_not_add_coverage_not_called() {
+    println!("not called and not covered");
+}
+
+fn add_coverage_1() {
+    println!("called and covered");
+}
+
+fn add_coverage_2() {
+    println!("called and covered");
+}
+
+fn add_coverage_not_called() {
+    println!("not called but covered");
+}
+
+// FIXME: These test-cases illustrate confusing results of nested functions.
+// See https://github.com/rust-lang/rust/issues/93319
+mod nested_fns {
+    #[no_coverage]
+    pub fn outer_not_covered(is_true: bool) {
+        fn inner(is_true: bool) {
+            if is_true {
+                println!("called and covered");
+            } else {
+                println!("absolutely not covered");
+            }
+        }
+        println!("called but not covered");
+        inner(is_true);
+    }
+
+    pub fn outer(is_true: bool) {
+        println!("called and covered");
+        inner_not_covered(is_true);
+
+        #[no_coverage]
+        fn inner_not_covered(is_true: bool) {
+            if is_true {
+                println!("called but not covered");
+            } else {
+                println!("absolutely not covered");
+            }
+        }
+    }
+
+    pub fn outer_both_covered(is_true: bool) {
+        println!("called and covered");
+        inner(is_true);
+
+        fn inner(is_true: bool) {
+            if is_true {
+                println!("called and covered");
+            } else {
+                println!("absolutely not covered");
+            }
+        }
+    }
+}
+
+fn main() {
+    let is_true = std::env::args().len() == 1;
+
+    do_not_add_coverage_1();
+    do_not_add_coverage_2();
+    add_coverage_1();
+    add_coverage_2();
+
+    nested_fns::outer_not_covered(is_true);
+    nested_fns::outer(is_true);
+    nested_fns::outer_both_covered(is_true);
+}
diff --git a/tests/run-make/coverage/overflow.rs b/tests/run-make/coverage/overflow.rs
new file mode 100644
index 00000000000..e537b0e95c3
--- /dev/null
+++ b/tests/run-make/coverage/overflow.rs
@@ -0,0 +1,63 @@
+#![allow(unused_assignments)]
+// expect-exit-status-101
+
+fn might_overflow(to_add: u32) -> u32 {
+    if to_add > 5 {
+        println!("this will probably overflow");
+    }
+    let add_to = u32::MAX - 5;
+    println!("does {} + {} overflow?", add_to, to_add);
+    let result = to_add + add_to;
+    println!("continuing after overflow check");
+    result
+}
+
+fn main() -> Result<(),u8> {
+    let mut countdown = 10;
+    while countdown > 0 {
+        if countdown == 1 {
+            let result = might_overflow(10);
+            println!("Result: {}", result);
+        } else if countdown < 5 {
+            let result = might_overflow(1);
+            println!("Result: {}", result);
+        }
+        countdown -= 1;
+    }
+    Ok(())
+}
+
+// Notes:
+//   1. Compare this program and its coverage results to those of the very similar test `assert.rs`,
+//      and similar tests `panic_unwind.rs`, abort.rs` and `try_error_result.rs`.
+//   2. This test confirms the coverage generated when a program passes or fails a
+//      compiler-generated `TerminatorKind::Assert` (based on an overflow check, in this case).
+//   3. Similar to how the coverage instrumentation handles `TerminatorKind::Call`,
+//      compiler-generated assertion failures are assumed to be a symptom of a program bug, not
+//      expected behavior. To simplify the coverage graphs and keep instrumented programs as
+//      small and fast as possible, `Assert` terminators are assumed to always succeed, and
+//      therefore are considered "non-branching" terminators. So, an `Assert` terminator does not
+//      get its own coverage counter.
+//   4. After an unhandled panic or failed Assert, coverage results may not always be intuitive.
+//      In this test, the final count for the statements after the `if` block in `might_overflow()`
+//      is 4, even though the lines after `to_add + add_to` were executed only 3 times. Depending
+//      on the MIR graph and the structure of the code, this count could have been 3 (which might
+//      have been valid for the overflowed add `+`, but should have been 4 for the lines before
+//      the overflow. The reason for this potential uncertainty is, a `CounterKind` is incremented
+//      via StatementKind::Counter at the end of the block, but (as in the case in this test),
+//      a CounterKind::Expression is always evaluated. In this case, the expression was based on
+//      a `Counter` incremented as part of the evaluation of the `if` expression, which was
+//      executed, and counted, 4 times, before reaching the overflow add.
+
+// If the program did not overflow, the coverage for `might_overflow()` would look like this:
+//
+//     4|       |fn might_overflow(to_add: u32) -> u32 {
+//     5|      4|    if to_add > 5 {
+//     6|      0|        println!("this will probably overflow");
+//     7|      4|    }
+//     8|      4|    let add_to = u32::MAX - 5;
+//     9|      4|    println!("does {} + {} overflow?", add_to, to_add);
+//    10|      4|    let result = to_add + add_to;
+//    11|      4|    println!("continuing after overflow check");
+//    12|      4|    result
+//    13|      4|}
diff --git a/tests/run-make/coverage/panic_unwind.rs b/tests/run-make/coverage/panic_unwind.rs
new file mode 100644
index 00000000000..03128c2cce6
--- /dev/null
+++ b/tests/run-make/coverage/panic_unwind.rs
@@ -0,0 +1,31 @@
+#![allow(unused_assignments)]
+// expect-exit-status-101
+
+fn might_panic(should_panic: bool) {
+    if should_panic {
+        println!("panicking...");
+        panic!("panics");
+    } else {
+        println!("Don't Panic");
+    }
+}
+
+fn main() -> Result<(), u8> {
+    let mut countdown = 10;
+    while countdown > 0 {
+        if countdown == 1 {
+            might_panic(true);
+        } else if countdown < 5 {
+            might_panic(false);
+        }
+        countdown -= 1;
+    }
+    Ok(())
+}
+
+// Notes:
+//   1. Compare this program and its coverage results to those of the similar tests `abort.rs` and
+//      `try_error_result.rs`.
+//   2. Since the `panic_unwind.rs` test is allowed to unwind, it is also allowed to execute the
+//      normal program exit cleanup, including writing out the current values of the coverage
+//      counters.
diff --git a/tests/run-make/coverage/partial_eq.rs b/tests/run-make/coverage/partial_eq.rs
new file mode 100644
index 00000000000..4ceaba9b111
--- /dev/null
+++ b/tests/run-make/coverage/partial_eq.rs
@@ -0,0 +1,46 @@
+// This test confirms an earlier problem was resolved, supporting the MIR graph generated by the
+// structure of this test.
+
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Version {
+    major: usize,
+    minor: usize,
+    patch: usize,
+}
+
+impl Version {
+    pub fn new(major: usize, minor: usize, patch: usize) -> Self {
+        Self {
+            major,
+            minor,
+            patch,
+        }
+    }
+}
+
+fn main() {
+    let version_3_2_1 = Version::new(3, 2, 1);
+    let version_3_3_0 = Version::new(3, 3, 0);
+
+    println!("{:?} < {:?} = {}", version_3_2_1, version_3_3_0, version_3_2_1 < version_3_3_0);
+}
+
+/*
+
+This test verifies a bug was fixed that otherwise generated this error:
+
+thread 'rustc' panicked at 'No counters provided the source_hash for function:
+    Instance {
+        def: Item(WithOptConstParam {
+            did: DefId(0:101 ~ autocfg[c44a]::version::{impl#2}::partial_cmp),
+            const_param_did: None
+        }),
+        substs: []
+    }'
+The `PartialOrd` derived by `Version` happened to generate a MIR that generated coverage
+without a code region associated with any `Counter`. Code regions were associated with at least
+one expression, which is allowed, but the `function_source_hash` was only passed to the codegen
+(coverage mapgen) phase from a `Counter`s code region. A new method was added to pass the
+`function_source_hash` without a code region, if necessary.
+
+*/
diff --git a/tests/run-make/coverage/simple_loop.rs b/tests/run-make/coverage/simple_loop.rs
new file mode 100644
index 00000000000..6f7f23475b8
--- /dev/null
+++ b/tests/run-make/coverage/simple_loop.rs
@@ -0,0 +1,35 @@
+#![allow(unused_assignments)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 0;
+
+    if
+        is_true
+    {
+        countdown
+        =
+            10
+        ;
+    }
+
+    loop
+    {
+        if
+            countdown
+                ==
+            0
+        {
+            break
+            ;
+        }
+        countdown
+        -=
+        1
+        ;
+    }
+}
diff --git a/tests/run-make/coverage/simple_match.rs b/tests/run-make/coverage/simple_match.rs
new file mode 100644
index 00000000000..be99e59a826
--- /dev/null
+++ b/tests/run-make/coverage/simple_match.rs
@@ -0,0 +1,43 @@
+#![allow(unused_assignments, unused_variables)]
+
+fn main() {
+    // Initialize test constants in a way that cannot be determined at compile time, to ensure
+    // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
+    // dependent conditions.
+    let is_true = std::env::args().len() == 1;
+
+    let mut countdown = 1;
+    if is_true {
+        countdown = 0;
+    }
+
+    for
+        _
+    in
+        0..2
+    {
+        let z
+        ;
+        match
+            countdown
+        {
+            x
+            if
+                x
+                    <
+                1
+            =>
+            {
+                z = countdown
+                ;
+                let y = countdown
+                ;
+                countdown = 10
+                ;
+            }
+            _
+            =>
+            {}
+        }
+    }
+}
diff --git a/tests/run-make/coverage/tight_inf_loop.rs b/tests/run-make/coverage/tight_inf_loop.rs
new file mode 100644
index 00000000000..cef99027aaa
--- /dev/null
+++ b/tests/run-make/coverage/tight_inf_loop.rs
@@ -0,0 +1,5 @@
+fn main() {
+    if false {
+        loop {}
+    }
+}
diff --git a/tests/run-make/coverage/try_error_result.rs b/tests/run-make/coverage/try_error_result.rs
new file mode 100644
index 00000000000..cd0acf72302
--- /dev/null
+++ b/tests/run-make/coverage/try_error_result.rs
@@ -0,0 +1,118 @@
+#![allow(unused_assignments)]
+// expect-exit-status-1
+
+fn call(return_error: bool) -> Result<(),()> {
+    if return_error {
+        Err(())
+    } else {
+        Ok(())
+    }
+}
+
+fn test1() -> Result<(),()> {
+    let mut
+        countdown = 10
+    ;
+    for
+        _
+    in
+        0..10
+    {
+        countdown
+            -= 1
+        ;
+        if
+            countdown < 5
+        {
+            call(/*return_error=*/ true)?;
+            call(/*return_error=*/ false)?;
+        }
+        else
+        {
+            call(/*return_error=*/ false)?;
+        }
+    }
+    Ok(())
+}
+
+struct Thing1;
+impl Thing1 {
+    fn get_thing_2(&self, return_error: bool) -> Result<Thing2,()> {
+        if return_error {
+            Err(())
+        } else {
+            Ok(Thing2{})
+        }
+    }
+}
+
+struct Thing2;
+impl Thing2 {
+    fn call(&self, return_error: bool) -> Result<u32,()> {
+        if return_error {
+            Err(())
+        } else {
+            Ok(57)
+        }
+    }
+}
+
+fn test2() -> Result<(),()> {
+    let thing1 = Thing1{};
+    let mut
+        countdown = 10
+    ;
+    for
+        _
+    in
+        0..10
+    {
+        countdown
+            -= 1
+        ;
+        if
+            countdown < 5
+        {
+            thing1.get_thing_2(/*err=*/ false)?.call(/*err=*/ true).expect_err("call should fail");
+            thing1
+                .
+                get_thing_2(/*return_error=*/ false)
+                ?
+                .
+                call(/*return_error=*/ true)
+                .
+                expect_err(
+                    "call should fail"
+                );
+            let val = thing1.get_thing_2(/*return_error=*/ true)?.call(/*return_error=*/ true)?;
+            assert_eq!(val, 57);
+            let val = thing1.get_thing_2(/*return_error=*/ true)?.call(/*return_error=*/ false)?;
+            assert_eq!(val, 57);
+        }
+        else
+        {
+            let val = thing1.get_thing_2(/*return_error=*/ false)?.call(/*return_error=*/ false)?;
+            assert_eq!(val, 57);
+            let val = thing1
+                .get_thing_2(/*return_error=*/ false)?
+                .call(/*return_error=*/ false)?;
+            assert_eq!(val, 57);
+            let val = thing1
+                .get_thing_2(/*return_error=*/ false)
+                ?
+                .call(/*return_error=*/ false)
+                ?
+                ;
+            assert_eq!(val, 57);
+        }
+    }
+    Ok(())
+}
+
+fn main() -> Result<(),()> {
+    test1().expect_err("test1 should fail");
+    test2()
+    ?
+    ;
+    Ok(())
+}
diff --git a/tests/run-make/coverage/unused.rs b/tests/run-make/coverage/unused.rs
new file mode 100644
index 00000000000..fb6113eb01c
--- /dev/null
+++ b/tests/run-make/coverage/unused.rs
@@ -0,0 +1,39 @@
+fn foo<T>(x: T) {
+    let mut i = 0;
+    while i < 10 {
+        i != 0 || i != 0;
+        i += 1;
+    }
+}
+
+fn unused_template_func<T>(x: T) {
+    let mut i = 0;
+    while i < 10 {
+        i != 0 || i != 0;
+        i += 1;
+    }
+}
+
+fn unused_func(mut a: u32) {
+    if a != 0 {
+        a += 1;
+    }
+}
+
+fn unused_func2(mut a: u32) {
+    if a != 0 {
+        a += 1;
+    }
+}
+
+fn unused_func3(mut a: u32) {
+    if a != 0 {
+        a += 1;
+    }
+}
+
+fn main() -> Result<(), u8> {
+    foo::<u32>(0);
+    foo::<f32>(0.0);
+    Ok(())
+}
diff --git a/tests/run-make/coverage/unused_mod.rs b/tests/run-make/coverage/unused_mod.rs
new file mode 100644
index 00000000000..679b4e53188
--- /dev/null
+++ b/tests/run-make/coverage/unused_mod.rs
@@ -0,0 +1,6 @@
+#[path = "lib/unused_mod_helper.rs"]
+mod unused_module;
+
+fn main() {
+    println!("hello world!");
+}
diff --git a/tests/run-make/coverage/uses_crate.rs b/tests/run-make/coverage/uses_crate.rs
new file mode 100644
index 00000000000..20cb05fe5b0
--- /dev/null
+++ b/tests/run-make/coverage/uses_crate.rs
@@ -0,0 +1,12 @@
+#![allow(unused_assignments, unused_variables)]
+// compile-flags: -C opt-level=3 # validates coverage now works with optimizations
+extern crate used_crate;
+
+fn main() {
+    used_crate::used_function();
+    let some_vec = vec![1, 2, 3, 4];
+    used_crate::used_only_from_bin_crate_generic_function(&some_vec);
+    used_crate::used_only_from_bin_crate_generic_function("used from bin uses_crate.rs");
+    used_crate::used_from_bin_crate_and_lib_crate_generic_function(some_vec);
+    used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function("interesting?");
+}
diff --git a/tests/run-make/coverage/uses_inline_crate.rs b/tests/run-make/coverage/uses_inline_crate.rs
new file mode 100644
index 00000000000..a7fe8532be3
--- /dev/null
+++ b/tests/run-make/coverage/uses_inline_crate.rs
@@ -0,0 +1,17 @@
+#![allow(unused_assignments, unused_variables)]
+
+// compile-flags: -C opt-level=3 # validates coverage now works with optimizations
+
+extern crate used_inline_crate;
+
+fn main() {
+    used_inline_crate::used_function();
+    used_inline_crate::used_inline_function();
+    let some_vec = vec![1, 2, 3, 4];
+    used_inline_crate::used_only_from_bin_crate_generic_function(&some_vec);
+    used_inline_crate::used_only_from_bin_crate_generic_function("used from bin uses_crate.rs");
+    used_inline_crate::used_from_bin_crate_and_lib_crate_generic_function(some_vec);
+    used_inline_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function(
+        "interesting?",
+    );
+}
diff --git a/tests/run-make/coverage/while.rs b/tests/run-make/coverage/while.rs
new file mode 100644
index 00000000000..781b90b3566
--- /dev/null
+++ b/tests/run-make/coverage/while.rs
@@ -0,0 +1,5 @@
+fn main() {
+    let num = 9;
+    while num >= 10 {
+    }
+}
diff --git a/tests/run-make/coverage/while_early_ret.rs b/tests/run-make/coverage/while_early_ret.rs
new file mode 100644
index 00000000000..1fcea9c85c4
--- /dev/null
+++ b/tests/run-make/coverage/while_early_ret.rs
@@ -0,0 +1,42 @@
+#![allow(unused_assignments)]
+// expect-exit-status-1
+
+fn main() -> Result<(),u8> {
+    let mut countdown = 10;
+    while
+        countdown
+            >
+        0
+    {
+        if
+            countdown
+                <
+            5
+        {
+            return
+                if
+                    countdown
+                        >
+                    8
+                {
+                    Ok(())
+                }
+                else
+                {
+                    Err(1)
+                }
+                ;
+        }
+        countdown
+            -=
+        1
+        ;
+    }
+    Ok(())
+}
+
+// ISSUE(77553): Originally, this test had `Err(1)` on line 22 (instead of `Ok(())`) and
+// `std::process::exit(2)` on line 26 (instead of `Err(1)`); and this worked as expected on Linux
+// and MacOS. But on Windows (MSVC, at least), the call to `std::process::exit()` exits the program
+// without saving the InstrProf coverage counters. The use of `std::process:exit()` is not critical
+// to the coverage test for early returns, but this is a limitation that should be fixed.
diff --git a/tests/run-make/coverage/yield.rs b/tests/run-make/coverage/yield.rs
new file mode 100644
index 00000000000..ff7616656ff
--- /dev/null
+++ b/tests/run-make/coverage/yield.rs
@@ -0,0 +1,37 @@
+#![feature(generators, generator_trait)]
+#![allow(unused_assignments)]
+
+use std::ops::{Generator, GeneratorState};
+use std::pin::Pin;
+
+fn main() {
+    let mut generator = || {
+        yield 1;
+        return "foo"
+    };
+
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Yielded(1) => {}
+        _ => panic!("unexpected value from resume"),
+    }
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Complete("foo") => {}
+        _ => panic!("unexpected value from resume"),
+    }
+
+    let mut generator = || {
+        yield 1;
+        yield 2;
+        yield 3;
+        return "foo"
+    };
+
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Yielded(1) => {}
+        _ => panic!("unexpected value from resume"),
+    }
+    match Pin::new(&mut generator).resume(()) {
+        GeneratorState::Yielded(2) => {}
+        _ => panic!("unexpected value from resume"),
+    }
+}