Files
wasmtime/crates/api/tests/traps.rs
Alex Crichton be85242a3f Expose precise offset information in wasmtime::FrameInfo (#1495)
* Consolidate trap/frame information

This commit removes `TrapRegistry` in favor of consolidating this
information in the `FRAME_INFO` we already have in the `wasmtime` crate.
This allows us to keep information generally in one place and have one
canonical location for "map this PC to some original wasm stuff". The
intent for this is to next update with enough information to go from a
program counter to a position in the original wasm file.

* Expose module offset information in `FrameInfo`

This commit implements functionality for `FrameInfo`, the wasm stack
trace of a `Trap`, to return the module/function offset. This allows
knowing the precise wasm location of each stack frame, instead of only
the main trap itself. The intention here is to provide more visibility
into the wasm source when something traps, so you know precisely where
calls were and where traps were, in order to assist in debugging.
Eventually we might use this information for mapping back to native
source languages as well (given sufficient debug information).

This change makes a previously-optional artifact of compilation always
computed on the cranelift side of things. This `ModuleAddressMap` is
then propagated to the same store of information other frame information
is stored within. This also removes the need for passing a `SourceLoc`
with wasm traps or to wasm trap creation, since the backtrace's wasm
frames will be able to infer their own `SourceLoc` from the relevant
program counters.
2020-04-15 08:00:15 -05:00

414 lines
11 KiB
Rust

use anyhow::Result;
use std::panic::{self, AssertUnwindSafe};
use wasmtime::*;
#[test]
fn test_trap_return() -> Result<()> {
let store = Store::default();
let wat = r#"
(module
(func $hello (import "" "hello"))
(func (export "run") (call $hello))
)
"#;
let module = Module::new(&store, wat)?;
let hello_type = FuncType::new(Box::new([]), Box::new([]));
let hello_func = Func::new(&store, hello_type, |_, _, _| Err(Trap::new("test 123")));
let instance = Instance::new(&module, &[hello_func.into()])?;
let run_func = instance.exports()[0]
.func()
.expect("expected function export");
let e = run_func
.call(&[])
.err()
.expect("error calling function")
.downcast::<Trap>()?;
assert_eq!(e.message(), "test 123");
Ok(())
}
#[test]
fn test_trap_trace() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $hello_mod
(func (export "run") (call $hello))
(func $hello (unreachable))
)
"#;
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[])?;
let run_func = instance.exports()[0]
.func()
.expect("expected function export");
let e = run_func
.call(&[])
.err()
.expect("error calling function")
.downcast::<Trap>()?;
let trace = e.trace();
assert_eq!(trace.len(), 2);
assert_eq!(trace[0].module_name().unwrap(), "hello_mod");
assert_eq!(trace[0].func_index(), 1);
assert_eq!(trace[0].func_name(), Some("hello"));
assert_eq!(trace[0].func_offset(), 1);
assert_eq!(trace[0].module_offset(), 0x26);
assert_eq!(trace[1].module_name().unwrap(), "hello_mod");
assert_eq!(trace[1].func_index(), 0);
assert_eq!(trace[1].func_name(), None);
assert_eq!(trace[1].func_offset(), 1);
assert_eq!(trace[1].module_offset(), 0x21);
assert!(
e.message().contains("unreachable"),
"wrong message: {}",
e.message()
);
Ok(())
}
#[test]
fn test_trap_trace_cb() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $hello_mod
(import "" "throw" (func $throw))
(func (export "run") (call $hello))
(func $hello (call $throw))
)
"#;
let fn_type = FuncType::new(Box::new([]), Box::new([]));
let fn_func = Func::new(&store, fn_type, |_, _, _| Err(Trap::new("cb throw")));
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[fn_func.into()])?;
let run_func = instance.exports()[0]
.func()
.expect("expected function export");
let e = run_func
.call(&[])
.err()
.expect("error calling function")
.downcast::<Trap>()?;
let trace = e.trace();
assert_eq!(trace.len(), 2);
assert_eq!(trace[0].module_name().unwrap(), "hello_mod");
assert_eq!(trace[0].func_index(), 2);
assert_eq!(trace[1].module_name().unwrap(), "hello_mod");
assert_eq!(trace[1].func_index(), 1);
assert_eq!(e.message(), "cb throw");
Ok(())
}
#[test]
fn test_trap_stack_overflow() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $rec_mod
(func $run (export "run") (call $run))
)
"#;
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[])?;
let run_func = instance.exports()[0]
.func()
.expect("expected function export");
let e = run_func
.call(&[])
.err()
.expect("error calling function")
.downcast::<Trap>()?;
let trace = e.trace();
assert!(trace.len() >= 32);
for i in 0..trace.len() {
assert_eq!(trace[i].module_name().unwrap(), "rec_mod");
assert_eq!(trace[i].func_index(), 0);
assert_eq!(trace[i].func_name(), Some("run"));
}
assert!(e.message().contains("call stack exhausted"));
Ok(())
}
#[test]
fn trap_display_pretty() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $m
(func $die unreachable)
(func call $die)
(func $foo call 1)
(func (export "bar") call $foo)
)
"#;
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[])?;
let run_func = instance.exports()[0]
.func()
.expect("expected function export");
let e = run_func.call(&[]).err().expect("error calling function");
assert_eq!(
e.to_string(),
"\
wasm trap: unreachable
wasm backtrace:
0: 0x23 - m!die
1: 0x27 - m!<wasm function 1>
2: 0x2c - m!foo
3: 0x31 - m!<wasm function 3>
"
);
Ok(())
}
#[test]
fn trap_display_multi_module() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $a
(func $die unreachable)
(func call $die)
(func $foo call 1)
(func (export "bar") call $foo)
)
"#;
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[])?;
let bar = instance.exports()[0].clone();
let wat = r#"
(module $b
(import "" "" (func $bar))
(func $middle call $bar)
(func (export "bar2") call $middle)
)
"#;
let module = Module::new(&store, wat)?;
let instance = Instance::new(&module, &[bar])?;
let bar2 = instance.exports()[0]
.func()
.expect("expected function export");
let e = bar2.call(&[]).err().expect("error calling function");
assert_eq!(
e.to_string(),
"\
wasm trap: unreachable
wasm backtrace:
0: 0x23 - a!die
1: 0x27 - a!<wasm function 1>
2: 0x2c - a!foo
3: 0x31 - a!<wasm function 3>
4: 0x29 - b!middle
5: 0x2e - b!<wasm function 2>
"
);
Ok(())
}
#[test]
fn trap_start_function_import() -> Result<()> {
let store = Store::default();
let binary = wat::parse_str(
r#"
(module $a
(import "" "" (func $foo))
(start $foo)
)
"#,
)?;
let module = Module::new(&store, &binary)?;
let sig = FuncType::new(Box::new([]), Box::new([]));
let func = Func::new(&store, sig, |_, _, _| Err(Trap::new("user trap")));
let err = Instance::new(&module, &[func.into()]).err().unwrap();
assert_eq!(err.downcast_ref::<Trap>().unwrap().message(), "user trap");
Ok(())
}
#[test]
fn rust_panic_import() -> Result<()> {
let store = Store::default();
let binary = wat::parse_str(
r#"
(module $a
(import "" "" (func $foo))
(import "" "" (func $bar))
(func (export "foo") call $foo)
(func (export "bar") call $bar)
)
"#,
)?;
let module = Module::new(&store, &binary)?;
let sig = FuncType::new(Box::new([]), Box::new([]));
let func = Func::new(&store, sig, |_, _, _| panic!("this is a panic"));
let instance = Instance::new(
&module,
&[
func.into(),
Func::wrap(&store, || panic!("this is another panic")).into(),
],
)?;
let func = instance.exports()[0].func().unwrap().clone();
let err = panic::catch_unwind(AssertUnwindSafe(|| {
drop(func.call(&[]));
}))
.unwrap_err();
assert_eq!(err.downcast_ref::<&'static str>(), Some(&"this is a panic"));
let func = instance.exports()[1].func().unwrap().clone();
let err = panic::catch_unwind(AssertUnwindSafe(|| {
drop(func.call(&[]));
}))
.unwrap_err();
assert_eq!(
err.downcast_ref::<&'static str>(),
Some(&"this is another panic")
);
Ok(())
}
#[test]
fn rust_panic_start_function() -> Result<()> {
let store = Store::default();
let binary = wat::parse_str(
r#"
(module $a
(import "" "" (func $foo))
(start $foo)
)
"#,
)?;
let module = Module::new(&store, &binary)?;
let sig = FuncType::new(Box::new([]), Box::new([]));
let func = Func::new(&store, sig, |_, _, _| panic!("this is a panic"));
let err = panic::catch_unwind(AssertUnwindSafe(|| {
drop(Instance::new(&module, &[func.into()]));
}))
.unwrap_err();
assert_eq!(err.downcast_ref::<&'static str>(), Some(&"this is a panic"));
let func = Func::wrap(&store, || panic!("this is another panic"));
let err = panic::catch_unwind(AssertUnwindSafe(|| {
drop(Instance::new(&module, &[func.into()]));
}))
.unwrap_err();
assert_eq!(
err.downcast_ref::<&'static str>(),
Some(&"this is another panic")
);
Ok(())
}
#[test]
fn mismatched_arguments() -> Result<()> {
let store = Store::default();
let binary = wat::parse_str(
r#"
(module $a
(func (export "foo") (param i32))
)
"#,
)?;
let module = Module::new(&store, &binary)?;
let instance = Instance::new(&module, &[])?;
let func = instance.exports()[0].func().unwrap().clone();
assert_eq!(
func.call(&[]).unwrap_err().to_string(),
"expected 1 arguments, got 0"
);
assert_eq!(
func.call(&[Val::F32(0)]).unwrap_err().to_string(),
"argument type mismatch",
);
assert_eq!(
func.call(&[Val::I32(0), Val::I32(1)])
.unwrap_err()
.to_string(),
"expected 1 arguments, got 2"
);
Ok(())
}
#[test]
fn call_signature_mismatch() -> Result<()> {
let store = Store::default();
let binary = wat::parse_str(
r#"
(module $a
(func $foo
i32.const 0
call_indirect)
(func $bar (param i32))
(start $foo)
(table 1 anyfunc)
(elem (i32.const 0) 1)
)
"#,
)?;
let module = Module::new(&store, &binary)?;
let err = Instance::new(&module, &[])
.err()
.unwrap()
.downcast::<Trap>()
.unwrap();
assert_eq!(err.message(), "wasm trap: indirect call type mismatch");
Ok(())
}
#[test]
fn start_trap_pretty() -> Result<()> {
let store = Store::default();
let wat = r#"
(module $m
(func $die unreachable)
(func call $die)
(func $foo call 1)
(func $start call $foo)
(start $start)
)
"#;
let module = Module::new(&store, wat)?;
let e = match Instance::new(&module, &[]) {
Ok(_) => panic!("expected failure"),
Err(e) => e.downcast::<Trap>()?,
};
assert_eq!(
e.to_string(),
"\
wasm trap: unreachable
wasm backtrace:
0: 0x1d - m!die
1: 0x21 - m!<wasm function 1>
2: 0x26 - m!foo
3: 0x2b - m!start
"
);
Ok(())
}