+//! Helpers used to print a message and abort in case of certain panics and some detected UB.
+
use crate::prelude::*;
-fn codegen_print(fx: &mut FunctionCx<'_, '_, impl cranelift_module::Backend>, msg: &str) {
- let puts = fx.module.declare_function("puts", Linkage::Import, &Signature {
- call_conv: CallConv::SystemV,
- params: vec![AbiParam::new(pointer_ty(fx.tcx))],
- returns: vec![],
- }).unwrap();
+fn codegen_print(fx: &mut FunctionCx<'_, '_, '_>, msg: &str) {
+ let puts = fx
+ .module
+ .declare_function(
+ "puts",
+ Linkage::Import,
+ &Signature {
+ call_conv: fx.target_config.default_call_conv,
+ params: vec![AbiParam::new(fx.pointer_type)],
+ returns: vec![AbiParam::new(types::I32)],
+ },
+ )
+ .unwrap();
let puts = fx.module.declare_func_in_func(puts, &mut fx.bcx.func);
- fx.add_entity_comment(puts, "puts");
-
- let symbol_name = fx.tcx.symbol_name(fx.instance);
- let real_msg = format!("trap at {:?} ({}): {}\0", fx.instance, symbol_name, msg);
- let mut data_ctx = DataContext::new();
- data_ctx.define(real_msg.as_bytes().to_vec().into_boxed_slice());
- let msg_id = fx.module.declare_data(&(symbol_name.as_str().to_string() + msg), Linkage::Local, false, None).unwrap();
-
- // Ignore DuplicateDefinition error, as the data will be the same
- let _ = fx.module.define_data(msg_id, &data_ctx);
+ if fx.clif_comments.enabled() {
+ fx.add_comment(puts, "puts");
+ }
- let local_msg_id = fx.module.declare_data_in_func(msg_id, fx.bcx.func);
- fx.add_entity_comment(local_msg_id, msg);
- let msg_ptr = fx.bcx.ins().global_value(pointer_ty(fx.tcx), local_msg_id);
+ let real_msg = format!("trap at {:?} ({}): {}\0", fx.instance, fx.symbol_name, msg);
+ let msg_ptr = fx.anonymous_str(&real_msg);
fx.bcx.ins().call(puts, &[msg_ptr]);
}
-/// Trap code: user0
-pub fn trap_panic(fx: &mut FunctionCx<'_, '_, impl cranelift_module::Backend>, msg: impl AsRef<str>) {
- codegen_print(fx, msg.as_ref());
- fx.bcx.ins().trap(TrapCode::User(0));
-}
-
+/// Use this for example when a function call should never return. This will fill the current block,
+/// so you can **not** add instructions to it afterwards.
+///
/// Trap code: user65535
-pub fn trap_unreachable(fx: &mut FunctionCx<'_, '_, impl cranelift_module::Backend>, msg: impl AsRef<str>) {
+pub(crate) fn trap_unreachable(fx: &mut FunctionCx<'_, '_, '_>, msg: impl AsRef<str>) {
codegen_print(fx, msg.as_ref());
- fx.bcx.ins().trap(TrapCode::User(!0));
+ fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
}
-
+/// Use this when something is unimplemented, but `libcore` or `libstd` requires it to codegen.
+/// Unlike `trap_unreachable` this will not fill the current block, so you **must** add instructions
+/// to it afterwards.
+///
/// Trap code: user65535
-pub fn trap_unreachable_ret_value<'tcx>(fx: &mut FunctionCx<'_, 'tcx, impl cranelift_module::Backend>, dest_layout: TyLayout<'tcx>, msg: impl AsRef<str>) -> CValue<'tcx> {
+pub(crate) fn trap_unimplemented(fx: &mut FunctionCx<'_, '_, '_>, msg: impl AsRef<str>) {
codegen_print(fx, msg.as_ref());
let true_ = fx.bcx.ins().iconst(types::I32, 1);
fx.bcx.ins().trapnz(true_, TrapCode::User(!0));
- let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
- CValue::by_ref(zero, dest_layout)
}
+/// Like `trap_unimplemented` but returns a fake value of the specified type.
+///
/// Trap code: user65535
-pub fn trap_unreachable_ret_place<'tcx>(fx: &mut FunctionCx<'_, 'tcx, impl cranelift_module::Backend>, dest_layout: TyLayout<'tcx>, msg: impl AsRef<str>) -> CPlace<'tcx> {
- codegen_print(fx, msg.as_ref());
- let true_ = fx.bcx.ins().iconst(types::I32, 1);
- fx.bcx.ins().trapnz(true_, TrapCode::User(!0));
- let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
- CPlace::for_addr(zero, dest_layout)
+pub(crate) fn trap_unimplemented_ret_value<'tcx>(
+ fx: &mut FunctionCx<'_, '_, 'tcx>,
+ dest_layout: TyAndLayout<'tcx>,
+ msg: impl AsRef<str>,
+) -> CValue<'tcx> {
+ trap_unimplemented(fx, msg);
+ CValue::by_ref(Pointer::const_addr(fx, 0), dest_layout)
}