core/irrt: add ErrorContext

nac3core/irrt/irrt/artiq_defs.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <irrt/int_defs.hpp>
+
+/*
+This file defines all ARTIQ-specific structures
+*/
+
+/**
+ * @brief ARTIQ's `cslice` object
+ *
+ * See https://docs.rs/cslice/0.3.0/src/cslice/lib.rs.html#33-37
+ */
+template <typename SizeT>
+struct CSlice {
+    const char *base;
+    SizeT len;
+};
+
+/**
+ * @brief Int type of ARTIQ's `Exception` IDs.
+ */
+typedef uint32_t ExceptionId;
+
+/**
+ * @brief ARTIQ's `Exception` object
+ *
+ * See https://github.com/m-labs/artiq/blob/b0d2705c385f64b6e6711c1726cd9178f40b598e/artiq/firmware/libeh/eh_artiq.rs#L1C1-L17C1
+ */
+template <typename SizeT>
+struct Exception {
+    ExceptionId id;
+    CSlice<SizeT> file;
+    uint32_t line;
+    uint32_t column;
+    CSlice<SizeT> function;
+    CSlice<SizeT> message;
+    uint32_t param;
+};

nac3core/irrt/irrt/error_context.hpp

@@ -0,0 +1,92 @@
+#pragma once
+
+#include <irrt/artiq_defs.hpp>
+#include <irrt/int_defs.hpp>
+#include <irrt/utils.hpp>
+
+namespace {
+/**
+ * @brief A (limited) set of known Exception IDs usable in IRRT
+ */
+struct ErrorContextExceptions {
+    ExceptionId index_error;
+    ExceptionId value_error;
+    ExceptionId assertion_error;
+    ExceptionId runtime_error;
+    ExceptionId type_error;
+};
+
+/**
+ * @brief The IRRT error context object
+ *
+ * This object contains all the details needed to propagate Python-like Exceptions in
+ * IRRT - within IRRT itself or propagate out of extern calls from nac3core.
+ */
+struct ErrorContext {
+    const ErrorContextExceptions *exceptions;
+
+    // Exception thrown by IRRT
+    ExceptionId exception_id;
+    // Points to empty c-string if there is no thrown Exception
+    const char *msg;
+    uint64_t param1;
+    uint64_t param2;
+    uint64_t param3;
+
+    void initialize(const ErrorContextExceptions *exceptions) {
+        this->exceptions = exceptions;
+        clear_error();
+    }
+
+    void clear_error() {
+        // NOTE: Point the msg to an empty str.
+        // Don't set it to nullptr - to implement `has_exception`
+        this->msg = "";
+    }
+
+    void set_exception(ExceptionId exception_id, const char *msg,
+                       uint64_t param1 = 0, uint64_t param2 = 0,
+                       uint64_t param3 = 0) {
+        this->exception_id = exception_id;
+        this->msg = msg;
+        this->param1 = param1;
+        this->param2 = param2;
+        this->param3 = param3;
+    }
+
+    bool has_exception() { return !cstr_utils::is_empty(msg); }
+
+    template <typename SizeT>
+    void get_exception_str(CSlice<SizeT> *dst_str) {
+        dst_str->base = msg;
+        dst_str->len = (SizeT)cstr_utils::length(msg);
+    }
+};
+}  // namespace
+
+extern "C" {
+void __nac3_error_context_initialize(ErrorContext *errctx,
+                                     ErrorContextExceptions *exceptions) {
+    errctx->initialize(exceptions);
+}
+
+bool __nac3_error_context_has_exception(ErrorContext *errctx) {
+    return errctx->has_exception();
+}
+
+void __nac3_error_context_get_exception_str(ErrorContext *errctx,
+                                            CSlice<int32_t> *dst_str) {
+    errctx->get_exception_str<int32_t>(dst_str);
+}
+
+void __nac3_error_context_get_exception_str64(ErrorContext *errctx,
+                                              CSlice<int64_t> *dst_str) {
+    errctx->get_exception_str<int64_t>(dst_str);
+}
+
+// Used for testing
+void __nac3_error_dummy_raise(ErrorContext *errctx) {
+    errctx->set_exception(errctx->exceptions->runtime_error,
+                      "Error thrown from __nac3_error_dummy_raise");
+}
+}

nac3core/irrt/irrt_everything.hpp

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <irrt/artiq_defs.hpp>
 #include <irrt/core.hpp>
+#include <irrt/error_context.hpp>
 #include <irrt/int_defs.hpp>
 #include <irrt/utils.hpp>

nac3core/irrt/test/util.hpp

@@ -114,3 +114,70 @@ void __assert_values_match(const char* file, int line, T expected, T got) {
 
 #define assert_values_match(expected, got) \
     __assert_values_match(__FILE__, __LINE__, expected, got)
+
+// A fake set of ExceptionIds for testing only
+const ErrorContextExceptions TEST_ERROR_CONTEXT_EXCEPTIONS = {
+    .index_error = 0,
+    .value_error = 1,
+    .assertion_error = 2,
+    .runtime_error = 3,
+    .type_error = 4,
+};
+
+ErrorContext create_testing_errctx() {
+    // Everything is global so it is fine to directly return a struct
+    // ErrorContext
+    ErrorContext errctx;
+    errctx.initialize(&TEST_ERROR_CONTEXT_EXCEPTIONS);
+    return errctx;
+}
+
+void print_errctx_content(ErrorContext* errctx) {
+    if (errctx->has_exception()) {
+        printf(
+            "(Exception ID %d): %s ... where param1 = %ld, param2 = %ld, "
+            "param3 = "
+            "%ld\n",
+            errctx->exception_id, errctx->msg, errctx->param1, errctx->param2,
+            errctx->param3);
+    } else {
+        printf("<no exception>\n");
+    }
+}
+
+void __assert_errctx_no_exception(const char* file, int line,
+                                  ErrorContext* errctx) {
+    if (errctx->has_exception()) {
+        print_assertion_failed(file, line);
+        printf("Expecting no exception but caught the following:\n\n");
+        print_errctx_content(errctx);
+        test_fail();
+    }
+}
+
+#define assert_errctx_no_exception(errctx) \
+    __assert_errctx_no_exception(__FILE__, __LINE__, errctx)
+
+void __assert_errctx_has_exception(const char* file, int line,
+                                   ErrorContext* errctx,
+                                   ExceptionId expected_exception_id) {
+    if (errctx->has_exception()) {
+        if (errctx->exception_id != expected_exception_id) {
+            print_assertion_failed(file, line);
+            printf(
+                "Expecting exception id %d but got exception id %d. Error "
+                "caught:\n\n",
+                expected_exception_id, errctx->exception_id);
+            print_errctx_content(errctx);
+            test_fail();
+        }
+    } else {
+        print_assertion_failed(file, line);
+        printf("Expecting an exception, but there is none.");
+        test_fail();
+    }
+}
+
+#define assert_errctx_has_exception(errctx, expected_exception_id) \
+    __assert_errctx_has_exception(__FILE__, __LINE__, errctx,      \
+                                  expected_exception_id)

nac3core/src/codegen/expr.rs

@@ -572,20 +572,16 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         })
     }
 
-    pub fn raise_exn<G: CodeGenerator + ?Sized>(
+    pub fn raise_exn_impl<G: CodeGenerator + ?Sized>(
         &mut self,
         generator: &mut G,
-        name: &str,
+        exn_id: Int<'ctx, ExceptionId>,
         msg: Struct<'ctx, CSlice>,
         params: [Option<Int<'ctx, Int64>>; 3],
         loc: Location,
     ) {
-        let type_context = generator.type_context(self.ctx);
         let exn_model = StructModel(Exception);
-        let exn_id_model = IntModel(ExceptionId::default());
 
-        let exn_id =
-            exn_id_model.constant(type_context, self.ctx, self.resolver.get_string_id(name) as u64);
         let exn = self.exception_val.unwrap_or_else(|| {
             let exn = exn_model.var_alloca(generator, self, Some("exn")).unwrap();
             *self.exception_val.insert(exn)
@@ -602,6 +598,23 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         gen_raise(generator, self, Some(exn), loc);
     }
 
+    pub fn raise_exn<G: CodeGenerator + ?Sized>(
+        &mut self,
+        generator: &mut G,
+        name: &str,
+        msg: Struct<'ctx, CSlice>,
+        params: [Option<Int<'ctx, Int64>>; 3],
+        loc: Location,
+    ) {
+        let tyctx = generator.type_context(self.ctx);
+        let exn_id_model = IntModel(ExceptionId::default());
+
+        let exn_id = self.resolver.get_string_id(name);
+        let exn_id = exn_id_model.constant(tyctx, self.ctx, exn_id as u64);
+
+        self.raise_exn_impl(generator, exn_id, msg, params, loc);
+    }
+
     pub fn make_assert<G: CodeGenerator + ?Sized>(
         &mut self,
         generator: &mut G,

nac3core/src/codegen/irrt/error_context.rs

@@ -0,0 +1,198 @@
+use super::util::{function::CallFunction, get_sizet_dependent_function_name};
+use crate::codegen::{
+    model::*,
+    structure::{cslice::CSlice, exception::ExceptionId},
+    CodeGenContext, CodeGenerator,
+};
+
+#[allow(clippy::struct_field_names)]
+pub struct ErrorContextExceptionsFields<F: FieldVisitor> {
+    pub index_error: F::Field<IntModel<ExceptionId>>,
+    pub value_error: F::Field<IntModel<ExceptionId>>,
+    pub assertion_error: F::Field<IntModel<ExceptionId>>,
+    pub runtime_error: F::Field<IntModel<ExceptionId>>,
+    pub type_error: F::Field<IntModel<ExceptionId>>,
+}
+
+/// Corresponds to IRRT's `struct ErrorContextExceptions`
+#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
+pub struct ErrorContextExceptions;
+
+impl StructKind for ErrorContextExceptions {
+    type Fields<F: FieldVisitor> = ErrorContextExceptionsFields<F>;
+
+    fn visit_fields<F: FieldVisitor>(&self, visitor: &mut F) -> Self::Fields<F> {
+        Self::Fields {
+            index_error: visitor.add("index_error"),
+            value_error: visitor.add("value_error"),
+            assertion_error: visitor.add("assertion_error"),
+            runtime_error: visitor.add("runtime_error"),
+            type_error: visitor.add("type_error"),
+        }
+    }
+}
+
+pub struct ErrorContextFields<F: FieldVisitor> {
+    pub exceptions: F::Field<PtrModel<StructModel<ErrorContextExceptions>>>,
+    pub exception_id: F::Field<IntModel<ExceptionId>>,
+    pub msg: F::Field<PtrModel<IntModel<Byte>>>,
+    pub param1: F::Field<IntModel<Int64>>,
+    pub param2: F::Field<IntModel<Int64>>,
+    pub param3: F::Field<IntModel<Int64>>,
+}
+
+/// Corresponds to IRRT's `struct ErrorContext`
+#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
+pub struct ErrorContext;
+
+impl StructKind for ErrorContext {
+    type Fields<F: FieldVisitor> = ErrorContextFields<F>;
+
+    fn visit_fields<F: FieldVisitor>(&self, visitor: &mut F) -> Self::Fields<F> {
+        Self::Fields {
+            exceptions: visitor.add("exceptions"),
+            exception_id: visitor.add("exception_id"),
+            msg: visitor.add("msg"),
+            param1: visitor.add("param1"),
+            param2: visitor.add("param2"),
+            param3: visitor.add("param3"),
+        }
+    }
+}
+
+/// Build an [`ErrorContextExceptions`] loaded with resolved [`ExceptionID`]s according to the [`SymbolResolver`].
+fn build_error_context_exceptions<'ctx>(
+    tyctx: TypeContext<'ctx>,
+    ctx: &CodeGenContext<'ctx, '_>,
+) -> Ptr<'ctx, StructModel<ErrorContextExceptions>> {
+    let exceptions =
+        StructModel(ErrorContextExceptions).alloca(tyctx, ctx, "error_context_exceptions");
+    let i32_model = IntModel(Int32);
+
+    let get_string_id = |string_id| {
+        i32_model.constant(tyctx, ctx.ctx, ctx.resolver.get_string_id(string_id) as u64)
+    };
+
+    exceptions.gep(ctx, |f| f.index_error).store(ctx, get_string_id("0:IndexError"));
+    exceptions.gep(ctx, |f| f.value_error).store(ctx, get_string_id("0:ValueError"));
+    exceptions.gep(ctx, |f| f.assertion_error).store(ctx, get_string_id("0:AssertionError"));
+    exceptions.gep(ctx, |f| f.runtime_error).store(ctx, get_string_id("0:RuntimeError"));
+    exceptions.gep(ctx, |f| f.type_error).store(ctx, get_string_id("0:TypeError"));
+
+    exceptions
+}
+
+pub fn call_nac3_error_context_initialize<'ctx>(
+    tyctx: TypeContext<'ctx>,
+    ctx: &CodeGenContext<'ctx, '_>,
+    perrctx: Ptr<'ctx, StructModel<ErrorContext>>,
+    pexceptions: Ptr<'ctx, StructModel<ErrorContextExceptions>>,
+) {
+    CallFunction::begin(tyctx, ctx, "__nac3_error_context_initialize")
+        .arg("errctx", perrctx)
+        .arg("exceptions", pexceptions)
+        .returning_void();
+}
+
+pub fn call_nac3_error_context_has_exception<'ctx>(
+    tyctx: TypeContext<'ctx>,
+    ctx: &CodeGenContext<'ctx, '_>,
+    perrctx: Ptr<'ctx, StructModel<ErrorContext>>,
+) -> Int<'ctx, Bool> {
+    CallFunction::begin(tyctx, ctx, "__nac3_error_context_has_exception")
+        .arg("errctx", perrctx)
+        .returning("has_exception")
+}
+
+pub fn call_nac3_error_context_get_exception_str<'ctx>(
+    tyctx: TypeContext<'ctx>,
+    ctx: &CodeGenContext<'ctx, '_>,
+    perrctx: Ptr<'ctx, StructModel<ErrorContext>>,
+    dst_str: Ptr<'ctx, StructModel<CSlice>>,
+) {
+    CallFunction::begin(
+        tyctx,
+        ctx,
+        &get_sizet_dependent_function_name(tyctx, "__nac3_error_context_get_exception_str"),
+    )
+    .arg("errctx", perrctx)
+    .arg("dst_str", dst_str)
+    .returning_void();
+}
+
+/// Setup a [`ErrorContext`] that could be passed to IRRT functions taking in a `ErrorContext* errctx`
+/// for error reporting purposes.
+///
+/// Also see: [`check_error_context`]
+pub fn setup_error_context<'ctx>(
+    tyctx: TypeContext<'ctx>,
+    ctx: &CodeGenContext<'ctx, '_>,
+) -> Ptr<'ctx, StructModel<ErrorContext>> {
+    let errctx_model = StructModel(ErrorContext);
+
+    let exceptions = build_error_context_exceptions(tyctx, ctx);
+    let errctx_ptr = errctx_model.alloca(tyctx, ctx, "errctx");
+
+    call_nac3_error_context_initialize(tyctx, ctx, errctx_ptr, exceptions);
+
+    errctx_ptr
+}
+
+/// Check a [`ErrorContext`] to see if it contains error. **If there is an error,
+/// a Pythonic exception will be raised in the firmware**.
+pub fn check_error_context<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    perrctx: Ptr<'ctx, StructModel<ErrorContext>>,
+) {
+    let tyctx = generator.type_context(ctx.ctx);
+    let cslice_model = StructModel(CSlice);
+
+    let current_bb = ctx.builder.get_insert_block().unwrap();
+    let irrt_has_exception_bb = ctx.ctx.insert_basic_block_after(current_bb, "irrt_has_exception");
+    let end_bb = ctx.ctx.insert_basic_block_after(irrt_has_exception_bb, "end");
+
+    // Inserting into `current_bb`
+    let has_exception = call_nac3_error_context_has_exception(tyctx, ctx, perrctx);
+    ctx.builder
+        .build_conditional_branch(has_exception.value, irrt_has_exception_bb, end_bb)
+        .unwrap();
+
+    // Inserting into `irrt_has_exception_bb`
+    ctx.builder.position_at_end(irrt_has_exception_bb);
+
+    // Load all the values for `ctx.make_assert_impl_by_id`
+    let pexception_str = cslice_model.alloca(tyctx, ctx, "exception_str");
+    call_nac3_error_context_get_exception_str(tyctx, ctx, perrctx, pexception_str);
+
+    let exception_id = perrctx.gep(ctx, |f| f.exception_id).load(tyctx, ctx, "exception_id");
+    let msg = pexception_str.load(tyctx, ctx, "msg");
+    let param1 = perrctx.gep(ctx, |f| f.param1).load(tyctx, ctx, "param1");
+    let param2 = perrctx.gep(ctx, |f| f.param2).load(tyctx, ctx, "param2");
+    let param3 = perrctx.gep(ctx, |f| f.param3).load(tyctx, ctx, "param3");
+
+    ctx.raise_exn_impl(
+        generator,
+        exception_id,
+        msg,
+        [Some(param1), Some(param2), Some(param3)],
+        ctx.current_loc,
+    );
+
+    // Position to `end_bb` for continuation
+    ctx.builder.position_at_end(end_bb);
+}
+
+pub fn call_nac3_dummy_raise<G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext,
+) {
+    let tyctx = generator.type_context(ctx.ctx);
+
+    let errctx = setup_error_context(tyctx, ctx);
+    CallFunction::begin(tyctx, ctx, "__nac3_error_dummy_raise")
+        .arg("errctx", errctx)
+        .returning_void();
+
+    check_error_context(generator, ctx, errctx);
+}

nac3core/src/codegen/irrt/mod.rs

@@ -1,6 +1,8 @@
 use crate::typecheck::typedef::Type;
 
+pub mod error_context;
 mod test;
+mod util;
 
 use super::model::*;
 use super::{

nac3core/src/codegen/irrt/util.rs

@@ -0,0 +1,103 @@
+use crate::codegen::model::*;
+
+// When [`TypeContext::size_type`] is 32-bits, the function name is "{fn_name}".
+// When [`TypeContext::size_type`] is 64-bits, the function name is "{fn_name}64".
+#[must_use]
+pub fn get_sizet_dependent_function_name(tyctx: TypeContext<'_>, name: &str) -> String {
+    let mut name = name.to_owned();
+    match tyctx.size_type.get_bit_width() {
+        32 => {}
+        64 => name.push_str("64"),
+        bit_width => {
+            panic!("Unsupported int type bit width {bit_width}, must be either 32-bits or 64-bits")
+        }
+    }
+    name
+}
+
+pub mod function {
+    use crate::codegen::{model::*, CodeGenContext};
+    use inkwell::{
+        types::{BasicMetadataTypeEnum, BasicType, FunctionType},
+        values::{AnyValue, BasicMetadataValueEnum, BasicValue, BasicValueEnum, CallSiteValue},
+    };
+    use itertools::Itertools;
+
+    #[derive(Debug, Clone, Copy)]
+    struct Arg<'ctx> {
+        ty: BasicMetadataTypeEnum<'ctx>,
+        val: BasicMetadataValueEnum<'ctx>,
+    }
+
+    /// Helper structure to reduce IRRT Inkwell function call boilerplate
+    /// TODO: Optimize
+    pub struct CallFunction<'ctx, 'a, 'b, 'c> {
+        tyctx: TypeContext<'ctx>,
+        ctx: &'b CodeGenContext<'ctx, 'a>,
+        /// Function name
+        name: &'c str,
+        /// Call arguments
+        args: Vec<Arg<'ctx>>,
+    }
+
+    impl<'ctx, 'a, 'b, 'c> CallFunction<'ctx, 'a, 'b, 'c> {
+        pub fn begin(
+            tyctx: TypeContext<'ctx>,
+            ctx: &'b CodeGenContext<'ctx, 'a>,
+            name: &'c str,
+        ) -> Self {
+            CallFunction { tyctx, ctx, name, args: Vec::new() }
+        }
+
+        /// Push a call argument to the function call.
+        ///
+        /// The `_name` parameter is there for self-documentation purposes.
+        #[allow(clippy::needless_pass_by_value)]
+        pub fn arg<M: Model>(mut self, _name: &str, arg: Instance<'ctx, M>) -> Self {
+            let arg = Arg {
+                ty: arg.model.get_type(self.tyctx, self.ctx.ctx).as_basic_type_enum().into(),
+                val: arg.value.as_basic_value_enum().into(),
+            };
+            self.args.push(arg);
+            self
+        }
+
+        /// Like [`CallFunction::returning_`] but `return_model` is automatically inferred.
+        pub fn returning<M: Model>(self, name: &str) -> Instance<'ctx, M> {
+            self.returning_(name, M::default())
+        }
+
+        /// Call the function and expect the function to return a value of type of `return_model`.
+        pub fn returning_<M: Model>(self, name: &str, return_model: M) -> Instance<'ctx, M> {
+            let ret_ty = return_model.get_type(self.tyctx, self.ctx.ctx);
+
+            let ret = self.get_function(|tys| ret_ty.fn_type(tys, false), name);
+            let ret = BasicValueEnum::try_from(ret.as_any_value_enum()).unwrap(); // Must work
+            let ret = return_model.check_value(self.tyctx, self.ctx.ctx, ret).unwrap(); // Must work
+            ret
+        }
+
+        /// Call the function and expect the function to return a void-type.
+        pub fn returning_void(self) {
+            let ret_ty = self.ctx.ctx.void_type();
+
+            let _ = self.get_function(|tys| ret_ty.fn_type(tys, false), "");
+        }
+
+        fn get_function<F>(&self, make_fn_type: F, return_value_name: &str) -> CallSiteValue<'ctx>
+        where
+            F: FnOnce(&[BasicMetadataTypeEnum<'ctx>]) -> FunctionType<'ctx>,
+        {
+            // Get the LLVM function, declare the function if it doesn't exist - it will be defined by other
+            // components of NAC3.
+            let func = self.ctx.module.get_function(self.name).unwrap_or_else(|| {
+                let tys = self.args.iter().map(|arg| arg.ty).collect_vec();
+                let fn_type = make_fn_type(&tys);
+                self.ctx.module.add_function(self.name, fn_type, None)
+            });
+
+            let vals = self.args.iter().map(|arg| arg.val).collect_vec();
+            self.ctx.builder.build_call(func, &vals, return_value_name).unwrap()
+        }
+    }
+}