//! Main evaluator loop and setting up the initial stack frame.
+use std::convert::TryFrom;
+use std::ffi::OsStr;
+
use rand::rngs::StdRng;
use rand::SeedableRng;
+use log::info;
-use rustc::hir::def_id::DefId;
-use rustc::ty::layout::{LayoutOf, Size};
-use rustc::ty::{self, TyCtxt};
-use syntax::source_map::DUMMY_SP;
+use rustc_hir::def_id::DefId;
+use rustc_middle::ty::{self, layout::LayoutCx, TyCtxt};
+use rustc_target::abi::LayoutOf;
-use crate::{
- struct_error, EnvVars, Evaluator, FnVal, HelpersEvalContextExt, InterpCx, InterpError,
- InterpResult, MemoryExtra, MiriMemoryKind, Pointer, Scalar, StackPopCleanup, Tag,
- TlsEvalContextExt,
-};
+use crate::*;
/// Configuration needed to spawn a Miri instance.
#[derive(Clone)]
pub struct MiriConfig {
- /// Determine if validity checking and Stacked Borrows are enabled.
+ /// Determine if validity checking is enabled.
pub validate: bool,
+ /// Determines if Stacked Borrows is enabled.
+ pub stacked_borrows: bool,
+ /// Determines if alignment checking is enabled.
+ pub check_alignment: bool,
/// Determines if communication with the host environment is enabled.
pub communicate: bool,
+ /// Determines if memory leaks should be ignored.
+ pub ignore_leaks: bool,
/// Environment variables that should always be isolated from the host.
pub excluded_env_vars: Vec<String>,
/// Command-line arguments passed to the interpreted program.
pub args: Vec<String>,
/// The seed to use when non-determinism or randomness are required (e.g. ptr-to-int cast, `getrandom()`).
pub seed: Option<u64>,
+ /// The stacked borrows pointer id to report about
+ pub tracked_pointer_tag: Option<PtrId>,
+ /// The stacked borrows call ID to report about
+ pub tracked_call_id: Option<CallId>,
+ /// The allocation id to report about.
+ pub tracked_alloc_id: Option<AllocId>,
+}
+
+impl Default for MiriConfig {
+ fn default() -> MiriConfig {
+ MiriConfig {
+ validate: true,
+ stacked_borrows: true,
+ check_alignment: true,
+ communicate: false,
+ ignore_leaks: false,
+ excluded_env_vars: vec![],
+ args: vec![],
+ seed: None,
+ tracked_pointer_tag: None,
+ tracked_call_id: None,
+ tracked_alloc_id: None,
+ }
+ }
}
-// Used by priroda.
+/// Returns a freshly created `InterpCx`, along with an `MPlaceTy` representing
+/// the location where the return value of the `start` lang item will be
+/// written to.
+/// Public because this is also used by `priroda`.
pub fn create_ecx<'mir, 'tcx: 'mir>(
tcx: TyCtxt<'tcx>,
main_id: DefId,
config: MiriConfig,
-) -> InterpResult<'tcx, InterpCx<'mir, 'tcx, Evaluator<'tcx>>> {
+) -> InterpResult<'tcx, (InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>, MPlaceTy<'tcx, Tag>)> {
+ let param_env = ty::ParamEnv::reveal_all();
+ let layout_cx = LayoutCx { tcx, param_env };
let mut ecx = InterpCx::new(
- tcx.at(syntax::source_map::DUMMY_SP),
- ty::ParamEnv::reveal_all(),
- Evaluator::new(config.communicate),
+ tcx,
+ rustc_span::source_map::DUMMY_SP,
+ param_env,
+ Evaluator::new(config.communicate, config.validate, layout_cx),
MemoryExtra::new(
StdRng::seed_from_u64(config.seed.unwrap_or(0)),
- config.validate,
+ config.stacked_borrows,
+ config.tracked_pointer_tag,
+ config.tracked_call_id,
+ config.tracked_alloc_id,
+ config.check_alignment,
),
);
// Complete initialization.
- EnvVars::init(&mut ecx, config.excluded_env_vars);
+ EnvVars::init(&mut ecx, config.excluded_env_vars)?;
+ MemoryExtra::init_extern_statics(&mut ecx)?;
// Setup first stack-frame
let main_instance = ty::Instance::mono(tcx, main_id);
let main_mir = ecx.load_mir(main_instance.def, None)?;
-
- if !main_mir.return_ty().is_unit() || main_mir.arg_count != 0 {
- throw_unsup_format!("miri does not support main functions without `fn()` type signatures");
+ if main_mir.arg_count != 0 {
+ bug!("main function must not take any arguments");
}
let start_id = tcx.lang_items().start_fn().unwrap();
start_id,
tcx.mk_substs(::std::iter::once(ty::subst::GenericArg::from(main_ret_ty))),
)
+ .unwrap()
.unwrap();
- let start_mir = ecx.load_mir(start_instance.def, None)?;
-
- if start_mir.arg_count != 3 {
- bug!(
- "'start' lang item should have three arguments, but has {}",
- start_mir.arg_count
- );
- }
-
- // Return value (in static memory so that it does not count as leak).
- let ret = ecx.layout_of(start_mir.return_ty())?;
- let ret_ptr = ecx.allocate(ret, MiriMemoryKind::Static.into());
-
- // Push our stack frame.
- ecx.push_stack_frame(
- start_instance,
- // There is no call site.
- DUMMY_SP,
- start_mir,
- Some(ret_ptr.into()),
- StackPopCleanup::None { cleanup: true },
- )?;
-
- let mut args = ecx.frame().body.args_iter();
// First argument: pointer to `main()`.
- let main_ptr = ecx
- .memory
- .create_fn_alloc(FnVal::Instance(main_instance));
- let dest = ecx.local_place(args.next().unwrap())?;
- ecx.write_scalar(Scalar::Ptr(main_ptr), dest)?;
-
- // Second argument (argc): `1`.
- let dest = ecx.local_place(args.next().unwrap())?;
- let argc = Scalar::from_uint(config.args.len() as u128, dest.layout.size);
- ecx.write_scalar(argc, dest)?;
- // Store argc for macOS's `_NSGetArgc`.
- {
- let argc_place = ecx.allocate(dest.layout, MiriMemoryKind::Env.into());
- ecx.write_scalar(argc, argc_place.into())?;
- ecx.machine.argc = Some(argc_place.ptr);
- }
-
+ let main_ptr = ecx.memory.create_fn_alloc(FnVal::Instance(main_instance));
+ // Second argument (argc): length of `config.args`.
+ let argc = Scalar::from_machine_usize(u64::try_from(config.args.len()).unwrap(), &ecx);
// Third argument (`argv`): created from `config.args`.
- let dest = ecx.local_place(args.next().unwrap())?;
- // For Windows, construct a command string with all the aguments.
- let mut cmd = String::new();
- for arg in config.args.iter() {
- if !cmd.is_empty() {
- cmd.push(' ');
+ let argv = {
+ // Put each argument in memory, collect pointers.
+ let mut argvs = Vec::<Scalar<Tag>>::new();
+ for arg in config.args.iter() {
+ // Make space for `0` terminator.
+ let size = u64::try_from(arg.len()).unwrap().checked_add(1).unwrap();
+ let arg_type = tcx.mk_array(tcx.types.u8, size);
+ let arg_place = ecx.allocate(ecx.layout_of(arg_type)?, MiriMemoryKind::Machine.into());
+ ecx.write_os_str_to_c_str(OsStr::new(arg), arg_place.ptr, size)?;
+ argvs.push(arg_place.ptr);
}
- cmd.push_str(&*shell_escape::windows::escape(arg.as_str().into()));
- }
- // Don't forget `0` terminator.
- cmd.push(std::char::from_u32(0).unwrap());
- // Collect the pointers to the individual strings.
- let mut argvs = Vec::<Pointer<Tag>>::new();
- for arg in config.args {
- // Add `0` terminator.
- let mut arg = arg.into_bytes();
- arg.push(0);
- argvs.push(
- ecx.memory
- .allocate_static_bytes(arg.as_slice(), MiriMemoryKind::Static.into()),
- );
- }
- // Make an array with all these pointers, in the Miri memory.
- let argvs_layout = ecx.layout_of(
- tcx.mk_array(tcx.mk_imm_ptr(tcx.types.u8), argvs.len() as u64),
- )?;
- let argvs_place = ecx.allocate(argvs_layout, MiriMemoryKind::Env.into());
- for (idx, arg) in argvs.into_iter().enumerate() {
- let place = ecx.mplace_field(argvs_place, idx as u64)?;
- ecx.write_scalar(Scalar::Ptr(arg), place.into())?;
- }
- ecx.memory
- .mark_immutable(argvs_place.ptr.assert_ptr().alloc_id)?;
- // Write a pointer to that place as the argument.
- let argv = argvs_place.ptr;
- ecx.write_scalar(argv, dest)?;
- // Store `argv` for macOS `_NSGetArgv`.
- {
- let argv_place = ecx.allocate(dest.layout, MiriMemoryKind::Env.into());
- ecx.write_scalar(argv, argv_place.into())?;
- ecx.machine.argv = Some(argv_place.ptr);
- }
- // Store command line as UTF-16 for Windows `GetCommandLineW`.
- {
- let cmd_utf16: Vec<u16> = cmd.encode_utf16().collect();
- let cmd_type = tcx.mk_array(tcx.types.u16, cmd_utf16.len() as u64);
- let cmd_place = ecx.allocate(ecx.layout_of(cmd_type)?, MiriMemoryKind::Env.into());
- ecx.machine.cmd_line = Some(cmd_place.ptr);
- // Store the UTF-16 string. We just allocated so we know the bounds are fine.
- let char_size = Size::from_bytes(2);
- for (idx, &c) in cmd_utf16.iter().enumerate() {
- let place = ecx.mplace_field(cmd_place, idx as u64)?;
- ecx.write_scalar(Scalar::from_uint(c, char_size), place.into())?;
+ // Make an array with all these pointers, in the Miri memory.
+ let argvs_layout =
+ ecx.layout_of(tcx.mk_array(tcx.mk_imm_ptr(tcx.types.u8), u64::try_from(argvs.len()).unwrap()))?;
+ let argvs_place = ecx.allocate(argvs_layout, MiriMemoryKind::Machine.into());
+ for (idx, arg) in argvs.into_iter().enumerate() {
+ let place = ecx.mplace_field(argvs_place, idx)?;
+ ecx.write_scalar(arg, place.into())?;
}
- }
+ ecx.memory.mark_immutable(argvs_place.ptr.assert_ptr().alloc_id)?;
+ // A pointer to that place is the 3rd argument for main.
+ let argv = argvs_place.ptr;
+ // Store `argc` and `argv` for macOS `_NSGetArg{c,v}`.
+ {
+ let argc_place =
+ ecx.allocate(ecx.machine.layouts.isize, MiriMemoryKind::Machine.into());
+ ecx.write_scalar(argc, argc_place.into())?;
+ ecx.machine.argc = Some(argc_place.ptr);
- args.next().expect_none("start lang item has more arguments than expected");
+ let argv_place = ecx.allocate(
+ ecx.layout_of(tcx.mk_imm_ptr(tcx.types.unit))?,
+ MiriMemoryKind::Machine.into(),
+ );
+ ecx.write_scalar(argv, argv_place.into())?;
+ ecx.machine.argv = Some(argv_place.ptr);
+ }
+ // Store command line as UTF-16 for Windows `GetCommandLineW`.
+ {
+ // Construct a command string with all the aguments.
+ let mut cmd = String::new();
+ for arg in config.args.iter() {
+ if !cmd.is_empty() {
+ cmd.push(' ');
+ }
+ cmd.push_str(&*shell_escape::windows::escape(arg.as_str().into()));
+ }
+ // Don't forget `0` terminator.
+ cmd.push(std::char::from_u32(0).unwrap());
+
+ let cmd_utf16: Vec<u16> = cmd.encode_utf16().collect();
+ let cmd_type = tcx.mk_array(tcx.types.u16, u64::try_from(cmd_utf16.len()).unwrap());
+ let cmd_place = ecx.allocate(ecx.layout_of(cmd_type)?, MiriMemoryKind::Machine.into());
+ ecx.machine.cmd_line = Some(cmd_place.ptr);
+ // Store the UTF-16 string. We just allocated so we know the bounds are fine.
+ for (idx, &c) in cmd_utf16.iter().enumerate() {
+ let place = ecx.mplace_field(cmd_place, idx)?;
+ ecx.write_scalar(Scalar::from_u16(c), place.into())?;
+ }
+ }
+ argv
+ };
+
+ // Return place (in static memory so that it does not count as leak).
+ let ret_place = ecx.allocate(ecx.machine.layouts.isize, MiriMemoryKind::Machine.into());
+ // Call start function.
+ ecx.call_function(
+ start_instance,
+ &[main_ptr.into(), argc.into(), argv.into()],
+ Some(ret_place.into()),
+ StackPopCleanup::None { cleanup: true },
+ )?;
// Set the last_error to 0
- let errno_layout = ecx.layout_of(tcx.types.u32)?;
- let errno_place = ecx.allocate(errno_layout, MiriMemoryKind::Static.into());
+ let errno_layout = ecx.machine.layouts.u32;
+ let errno_place = ecx.allocate(errno_layout, MiriMemoryKind::Machine.into());
ecx.write_scalar(Scalar::from_u32(0), errno_place.into())?;
ecx.machine.last_error = Some(errno_place);
- Ok(ecx)
+ Ok((ecx, ret_place))
}
-pub fn eval_main<'tcx>(tcx: TyCtxt<'tcx>, main_id: DefId, config: MiriConfig) {
- let mut ecx = match create_ecx(tcx, main_id, config) {
- Ok(ecx) => ecx,
- Err(mut err) => {
+/// Evaluates the main function specified by `main_id`.
+/// Returns `Some(return_code)` if program executed completed.
+/// Returns `None` if an evaluation error occured.
+pub fn eval_main<'tcx>(tcx: TyCtxt<'tcx>, main_id: DefId, config: MiriConfig) -> Option<i64> {
+ // Copy setting before we move `config`.
+ let ignore_leaks = config.ignore_leaks;
+
+ let (mut ecx, ret_place) = match create_ecx(tcx, main_id, config) {
+ Ok(v) => v,
+ Err(err) => {
err.print_backtrace();
- panic!("Miri initialziation error: {}", err.kind)
+ panic!("Miri initialization error: {}", err.kind)
}
};
// Perform the main execution.
- let res: InterpResult<'_> = (|| {
- ecx.run()?;
- ecx.run_tls_dtors()
+ let res: InterpResult<'_, i64> = (|| {
+ // Main loop.
+ loop {
+ let info = ecx.preprocess_diagnostics();
+ match ecx.schedule()? {
+ SchedulingAction::ExecuteStep => {
+ assert!(ecx.step()?, "a terminated thread was scheduled for execution");
+ }
+ SchedulingAction::ExecuteTimeoutCallback => {
+ assert!(ecx.machine.communicate,
+ "scheduler callbacks require disabled isolation, but the code \
+ that created the callback did not check it");
+ ecx.run_timeout_callback()?;
+ }
+ SchedulingAction::ExecuteDtors => {
+ // This will either enable the thread again (so we go back
+ // to `ExecuteStep`), or determine that this thread is done
+ // for good.
+ ecx.schedule_next_tls_dtor_for_active_thread()?;
+ }
+ SchedulingAction::Stop => {
+ break;
+ }
+ }
+ ecx.process_diagnostics(info);
+ }
+ let return_code = ecx.read_scalar(ret_place.into())?.check_init()?.to_machine_isize(&ecx)?;
+ Ok(return_code)
})();
+ // Machine cleanup.
+ EnvVars::cleanup(&mut ecx).unwrap();
+
// Process the result.
match res {
- Ok(()) => {
- let leaks = ecx.memory.leak_report();
- // Disable the leak test on some platforms where we do not
- // correctly implement TLS destructors.
- let target_os = ecx.tcx.tcx.sess.target.target.target_os.to_lowercase();
- let ignore_leaks = target_os == "windows" || target_os == "macos";
- if !ignore_leaks && leaks != 0 {
- tcx.sess.err("the evaluated program leaked memory");
- }
- }
- Err(mut e) => {
- // Special treatment for some error kinds
- let msg = match e.kind {
- InterpError::Exit(code) => std::process::exit(code),
- err_unsup!(NoMirFor(..)) =>
- format!("{}. Did you set `MIRI_SYSROOT` to a Miri-enabled sysroot? You can prepare one with `cargo miri setup`.", e),
- _ => e.to_string()
- };
- e.print_backtrace();
- if let Some(frame) = ecx.stack().last() {
- let block = &frame.body.basic_blocks()[frame.block];
- let span = if frame.stmt < block.statements.len() {
- block.statements[frame.stmt].source_info.span
- } else {
- block.terminator().source_info.span
- };
-
- let msg = format!("Miri evaluation error: {}", msg);
- let mut err = struct_error(ecx.tcx.tcx.at(span), msg.as_str());
- let frames = ecx.generate_stacktrace(None);
- err.span_label(span, msg);
- // We iterate with indices because we need to look at the next frame (the caller).
- for idx in 0..frames.len() {
- let frame_info = &frames[idx];
- let call_site_is_local = frames.get(idx + 1).map_or(false, |caller_info| {
- caller_info.instance.def_id().is_local()
- });
- if call_site_is_local {
- err.span_note(frame_info.call_site, &frame_info.to_string());
- } else {
- err.note(&frame_info.to_string());
- }
- }
- err.emit();
- } else {
- ecx.tcx.sess.err(&msg);
- }
-
- for (i, frame) in ecx.stack().iter().enumerate() {
- trace!("-------------------");
- trace!("Frame {}", i);
- trace!(" return: {:?}", frame.return_place.map(|p| *p));
- for (i, local) in frame.locals.iter().enumerate() {
- trace!(" local {}: {:?}", i, local.value);
+ Ok(return_code) => {
+ if !ignore_leaks {
+ info!("Additonal static roots: {:?}", ecx.machine.static_roots);
+ let leaks = ecx.memory.leak_report(&ecx.machine.static_roots);
+ if leaks != 0 {
+ tcx.sess.err("the evaluated program leaked memory");
+ // Ignore the provided return code - let the reported error
+ // determine the return code.
+ return None;
}
}
+ Some(return_code)
}
+ Err(e) => report_error(&ecx, e),
}
}