Migrate intrinsics module to use StableMIR (rust-lang#2939)

This one was fairly straight forward. It still uses a few internal APIs
for user friendly errors, for type layout, SIMD information and
intrinsic validity.

Author: celinval

kani-compiler/src/codegen_cprover_gotoc/codegen/assert.rs

@@ -150,7 +150,7 @@ impl<'tcx> GotocCtx<'tcx> {
 
     /// Generate a cover statement for code coverage reports.
     pub fn codegen_coverage(&self, span: Span) -> Stmt {
-        let loc = self.codegen_caller_span(&Some(span));
+        let loc = self.codegen_caller_span(&span);
         // Should use Stmt::cover, but currently this doesn't work with CBMC
         // unless it is run with '--cover cover' (see
         // https://github.com/diffblue/cbmc/issues/6613). So for now use
@@ -214,9 +214,9 @@ impl<'tcx> GotocCtx<'tcx> {
         &self,
         property_class: PropertyClass,
         msg: &str,
-        span: Option<Span>,
+        span: SpanStable,
     ) -> Stmt {
-        let loc = self.codegen_caller_span(&span);
+        let loc = self.codegen_caller_span_stable(span);
         self.codegen_assert_assume_false(property_class, msg, loc)
     }
 
@@ -228,9 +228,7 @@ impl<'tcx> GotocCtx<'tcx> {
         let msg = self.extract_const_message(&fargs[0]).unwrap_or(String::from(
             "This is a placeholder message; Kani doesn't support message formatted at runtime",
         ));
-
-        let loc = self.codegen_caller_span_stable(span);
-        self.codegen_assert_assume_false(PropertyClass::Assertion, &msg, loc)
+        self.codegen_fatal_error(PropertyClass::Assertion, &msg, span)
     }
 
     /// Kani does not currently support all MIR constructs.

kani-compiler/src/codegen_cprover_gotoc/codegen/intrinsic.rs

@@ -393,7 +393,7 @@ impl<'tcx> GotocCtx<'tcx> {
                 // Check that computing `offset` in bytes would not overflow
                 let (offset_bytes, bytes_overflow_check) = self.count_in_bytes(
                     ce2.clone().cast_to(Type::ssize_t()),
-                    rustc_internal::internal(ty),
+                    ty,
                     Type::ssize_t(),
                     "offset",
                     loc,

kani-compiler/src/codegen_cprover_gotoc/codegen/rvalue.rs

@@ -33,20 +33,16 @@ impl<'tcx> GotocCtx<'tcx> {
     }
 
     pub fn codegen_caller_span_stable(&self, sp: SpanStable) -> Location {
-        self.codegen_caller_span(&Some(rustc_internal::internal(sp)))
+        self.codegen_caller_span(&rustc_internal::internal(sp))
     }
 
     /// Get the location of the caller. This will attempt to reach the macro caller.
     /// This function uses rustc_span methods designed to returns span for the macro which
     /// originally caused the expansion to happen.
     /// Note: The API stops backtracing at include! boundary.
-    pub fn codegen_caller_span(&self, sp: &Option<Span>) -> Location {
-        if let Some(span) = sp {
-            let topmost = span.ctxt().outer_expn().expansion_cause().unwrap_or(*span);
-            self.codegen_span(&topmost)
-        } else {
-            Location::none()
-        }
+    pub fn codegen_caller_span(&self, span: &Span) -> Location {
+        let topmost = span.ctxt().outer_expn().expansion_cause().unwrap_or(*span);
+        self.codegen_span(&topmost)
     }
 
     pub fn codegen_span_option(&self, sp: Option<Span>) -> Location {

kani-compiler/src/codegen_cprover_gotoc/codegen/span.rs

@@ -3,6 +3,7 @@
 use super::typ::TypeExt;
 use super::typ::FN_RETURN_VOID_VAR_NAME;
 use super::PropertyClass;
+use crate::codegen_cprover_gotoc::codegen::ty_stable::StableConverter;
 use crate::codegen_cprover_gotoc::{GotocCtx, VtableCtx};
 use crate::unwrap_or_return_codegen_unimplemented_stmt;
 use cbmc::goto_program::{Expr, Location, Stmt, Type};
@@ -18,7 +19,7 @@ use rustc_smir::rustc_internal;
 use rustc_span::Span;
 use rustc_target::abi::VariantIdx;
 use rustc_target::abi::{FieldsShape, Primitive, TagEncoding, Variants};
-use stable_mir::mir::Place as PlaceStable;
+use stable_mir::mir::{Operand as OperandStable, Place as PlaceStable};
 use tracing::{debug, debug_span, trace};
 
 impl<'tcx> GotocCtx<'tcx> {
@@ -68,15 +69,13 @@ impl<'tcx> GotocCtx<'tcx> {
             StatementKind::Intrinsic(box NonDivergingIntrinsic::CopyNonOverlapping(
                 mir::CopyNonOverlapping { ref src, ref dst, ref count },
             )) => {
+                let operands =
+                    [src, dst, count].map(|op| StableConverter::convert_operand(self, op.clone()));
                 // Pack the operands and their types, then call `codegen_copy`
-                let fargs = vec![
-                    self.codegen_operand(src),
-                    self.codegen_operand(dst),
-                    self.codegen_operand(count),
-                ];
-                let farg_types =
-                    &[self.operand_ty(src), self.operand_ty(dst), self.operand_ty(count)];
-                self.codegen_copy("copy_nonoverlapping", true, fargs, farg_types, None, location)
+                let fargs =
+                    operands.iter().map(|op| self.codegen_operand_stable(op)).collect::<Vec<_>>();
+                let farg_types = operands.map(|op| self.operand_ty_stable(&op));
+                self.codegen_copy("copy_nonoverlapping", true, fargs, &farg_types, None, location)
             }
             StatementKind::Intrinsic(box NonDivergingIntrinsic::Assume(ref op)) => {
                 let cond = self.codegen_operand(op).cast_to(Type::bool());
@@ -474,20 +473,20 @@ impl<'tcx> GotocCtx<'tcx> {
     /// This is used because we ignore ZST arguments, except for intrinsics.
     pub(crate) fn codegen_funcall_args(
         &mut self,
-        args: &[Operand<'tcx>],
+        args: &[OperandStable],
         skip_zst: bool,
     ) -> Vec<Expr> {
         let fargs = args
             .iter()
-            .filter_map(|o| {
-                let op_ty = self.operand_ty(o);
-                if op_ty.is_bool() {
-                    Some(self.codegen_operand(o).cast_to(Type::c_bool()))
-                } else if !self.is_zst(op_ty) || !skip_zst {
-                    Some(self.codegen_operand(o))
+            .filter_map(|op| {
+                let op_ty = self.operand_ty_stable(op);
+                if op_ty.kind().is_bool() {
+                    Some(self.codegen_operand_stable(op).cast_to(Type::c_bool()))
+                } else if !self.is_zst_stable(op_ty) || !skip_zst {
+                    Some(self.codegen_operand_stable(op))
                 } else {
                     // We ignore ZST types.
-                    debug!(arg=?o, "codegen_funcall_args ignore");
+                    debug!(arg=?op, "codegen_funcall_args ignore");
                     None
                 }
             })
@@ -517,13 +516,26 @@ impl<'tcx> GotocCtx<'tcx> {
         span: Span,
     ) -> Stmt {
         debug!(?func, ?args, ?destination, ?span, "codegen_funcall");
-        if self.is_intrinsic(func) {
-            return self.codegen_funcall_of_intrinsic(func, args, destination, target, span);
+        let func_stable = StableConverter::convert_operand(self, func.clone());
+        let args_stable = args
+            .iter()
+            .map(|arg| StableConverter::convert_operand(self, arg.clone()))
+            .collect::<Vec<_>>();
+        let destination_stable = StableConverter::convert_place(self, *destination);
+
+        if self.is_intrinsic(&func_stable) {
+            return self.codegen_funcall_of_intrinsic(
+                &func_stable,
+                &args_stable,
+                &destination_stable,
+                target.map(|bb| bb.index()),
+                rustc_internal::stable(span),
+            );
         }
 
         let loc = self.codegen_span(&span);
         let funct = self.operand_ty(func);
-        let mut fargs = self.codegen_funcall_args(args, true);
+        let mut fargs = self.codegen_funcall_args(&args_stable, true);
         match &funct.kind() {
             ty::FnDef(defid, subst) => {
                 let instance =
@@ -700,13 +712,13 @@ impl<'tcx> GotocCtx<'tcx> {
     /// A MIR [Place] is an L-value (i.e. the LHS of an assignment).
     ///
     /// In Kani, we slightly optimize the special case for Unit and don't assign anything.
-    pub(crate) fn codegen_expr_to_place_stable(&mut self, p: &PlaceStable, e: Expr) -> Stmt {
-        if e.typ().is_unit() {
-            e.as_stmt(Location::none())
+    pub(crate) fn codegen_expr_to_place_stable(&mut self, place: &PlaceStable, expr: Expr) -> Stmt {
+        if self.place_ty_stable(place).kind().is_unit() {
+            expr.as_stmt(Location::none())
         } else {
-            unwrap_or_return_codegen_unimplemented_stmt!(self, self.codegen_place_stable(p))
+            unwrap_or_return_codegen_unimplemented_stmt!(self, self.codegen_place_stable(place))
                 .goto_expr
-                .assign(e, Location::none())
+                .assign(expr, Location::none())
         }
     }
 

kani-compiler/src/codegen_cprover_gotoc/codegen/statement.rs

@@ -33,11 +33,11 @@ impl<'tcx> GotocCtx<'tcx> {
         self.codegen_ty_ref(rustc_internal::internal(ty))
     }
 
-    pub fn local_ty_stable(&mut self, local: Local) -> Ty {
+    pub fn local_ty_stable(&self, local: Local) -> Ty {
         self.current_fn().body().local_decl(local).unwrap().ty
     }
 
-    pub fn operand_ty_stable(&mut self, operand: &Operand) -> Ty {
+    pub fn operand_ty_stable(&self, operand: &Operand) -> Ty {
         operand.ty(self.current_fn().body().locals()).unwrap()
     }
 
@@ -89,6 +89,11 @@ impl<'tcx> GotocCtx<'tcx> {
     pub fn rvalue_ty_stable(&self, rvalue: &Rvalue) -> Ty {
         rvalue.ty(self.current_fn().body().locals()).unwrap()
     }
+
+    pub fn simd_size_and_type(&self, ty: Ty) -> (u64, Ty) {
+        let (sz, ty) = rustc_internal::internal(ty).simd_size_and_type(self.tcx);
+        (sz, rustc_internal::stable(ty))
+    }
 }
 /// If given type is a Ref / Raw ref, return the pointee type.
 pub fn pointee_type(mir_type: Ty) -> Option<Ty> {
@@ -99,6 +104,14 @@ pub fn pointee_type(mir_type: Ty) -> Option<Ty> {
     }
 }
 
+/// Convert a type into a user readable type representation.
+///
+/// This should be replaced by StableMIR `pretty_ty()` after
+/// <https://github.com/rust-lang/rust/pull/118364> is merged.
+pub fn pretty_ty(ty: Ty) -> String {
+    rustc_internal::internal(ty).to_string()
+}
+
 /// Convert internal rustc's structs into StableMIR ones.
 ///
 /// The body of a StableMIR instance already comes monomorphized, which is different from rustc's

kani-compiler/src/codegen_cprover_gotoc/codegen/ty_stable.rs

@@ -1898,12 +1898,6 @@ fn common_vtable_fields(drop_in_place: Type) -> Vec<DatatypeComponent> {
     fields
 }
 
-/// The mir type is a mir pointer type (Ref or RawPtr).
-/// This will return false for all smart pointers. See is_std_pointer for a more complete check.
-pub fn is_pointer(mir_type: Ty) -> bool {
-    return pointee_type(mir_type).is_some();
-}
-
 /// If given type is a Ref / Raw ref, return the pointee type.
 pub fn pointee_type(mir_type: Ty) -> Option<Ty> {
     match mir_type.kind() {

kani-compiler/src/codegen_cprover_gotoc/codegen/typ.rs

@@ -1,12 +1,12 @@
 // Copyright Kani Contributors
 // SPDX-License-Identifier: Apache-2.0 OR MIT
 use super::super::codegen::TypeExt;
-use crate::codegen_cprover_gotoc::codegen::typ::{is_pointer, pointee_type};
 use crate::codegen_cprover_gotoc::GotocCtx;
 use cbmc::goto_program::{Expr, ExprValue, Location, SymbolTable, Type};
 use cbmc::{btree_string_map, InternedString};
-use rustc_middle::ty::layout::LayoutOf;
-use rustc_middle::ty::Ty;
+use rustc_middle::ty::TyCtxt;
+use rustc_smir::rustc_internal;
+use stable_mir::ty::Span;
 use tracing::debug;
 
 // Should move into rvalue
@@ -20,21 +20,6 @@ pub fn dynamic_fat_ptr(typ: Type, data: Expr, vtable: Expr, symbol_table: &Symbo
 }
 
 impl<'tcx> GotocCtx<'tcx> {
-    /// Generates an expression `(ptr as usize) % align_of(T) == 0`
-    /// to determine if a pointer `ptr` with pointee type `T` is aligned.
-    pub fn is_ptr_aligned(&mut self, typ: Ty<'tcx>, ptr: Expr) -> Expr {
-        // Ensure `typ` is a pointer, then extract the pointee type
-        assert!(is_pointer(typ));
-        let pointee_type = pointee_type(typ).unwrap();
-        // Obtain the alignment for the pointee type `T`
-        let layout = self.layout_of(pointee_type);
-        let align = Expr::int_constant(layout.align.abi.bytes(), Type::size_t());
-        // Cast the pointer to `usize` and return the alignment expression
-        let cast_ptr = ptr.cast_to(Type::size_t());
-        let zero = Type::size_t().zero();
-        cast_ptr.rem(align).eq(zero)
-    }
-
     pub fn unsupported_msg(item: &str, url: Option<&str>) -> String {
         let mut s = format!("{item} is not currently supported by Kani");
         if let Some(url) = url {
@@ -207,3 +192,7 @@ impl<'tcx> GotocCtx<'tcx> {
         assert!(component.typ().is_pointer() || component.typ().is_rust_fat_ptr(&self.symbol_table))
     }
 }
+
+pub fn span_err(tcx: TyCtxt, span: Span, msg: String) {
+    tcx.sess.span_err(rustc_internal::internal(span), msg);
+}