charon_lib/ast/
ullbc_ast.rs

1//! "Unstructured LLBC" ast (ULLBC). This is LLBC before the control-flow
2//! reconstruction. In effect, this is a cleaned up version of MIR.
3pub use crate::ast::*;
4use derive_generic_visitor::{Drive, DriveMut};
5use macros::{EnumAsGetters, EnumIsA, VariantIndexArity, VariantName};
6use serde::{Deserialize, Serialize};
7
8// Block identifier. Similar to rust's `BasicBlock`.
9generate_index_type!(BlockId, "Block");
10
11// The entry block of a function is always the block with id 0
12pub static START_BLOCK_ID: BlockId = BlockId::ZERO;
13
14#[charon::rename("Blocks")]
15pub type BodyContents = Vector<BlockId, BlockData>;
16pub type ExprBody = GExprBody<BodyContents>;
17
18/// A raw statement: a statement without meta data.
19#[derive(
20    Debug, Clone, EnumIsA, EnumAsGetters, VariantName, Serialize, Deserialize, Drive, DriveMut,
21)]
22pub enum RawStatement {
23    Assign(Place, Rvalue),
24    /// A call. For now, we don't support dynamic calls (i.e. to a function pointer in memory).
25    SetDiscriminant(Place, VariantId),
26    /// Equivalent to std::intrinsics::copy_nonoverlapping; this is not modelled as a function
27    /// call as it cannot diverge
28    CopyNonOverlapping(Box<CopyNonOverlapping>),
29    /// Indicates that this local should be allocated; if it is already allocated, this frees
30    /// the local and re-allocates it. The return value and arguments do not receive a
31    /// `StorageLive`. We ensure in the micro-pass `insert_storage_lives` that all other locals
32    /// have a `StorageLive` associated with them.
33    StorageLive(LocalId),
34    /// Indicates that this local should be deallocated; if it is already deallocated, this is
35    /// a no-op. A local may not have a `StorageDead` in the function's body, in which case it
36    /// is implicitly deallocated at the end of the function.
37    StorageDead(LocalId),
38    Deinit(Place),
39    Drop(Place),
40    /// A built-in assert, which corresponds to runtime checks that we remove, namely: bounds
41    /// checks, over/underflow checks, div/rem by zero checks, pointer alignement check.
42    Assert(Assert),
43    /// Does nothing. Useful for passes.
44    Nop,
45    #[charon::opaque]
46    #[drive(skip)]
47    Error(String),
48}
49
50#[derive(Debug, Clone, Serialize, Deserialize, Drive, DriveMut)]
51pub struct Statement {
52    pub span: Span,
53    pub content: RawStatement,
54    /// Comments that precede this statement.
55    // This is filled in a late pass after all the control-flow manipulation.
56    #[drive(skip)]
57    pub comments_before: Vec<String>,
58}
59
60#[derive(
61    Debug,
62    Clone,
63    EnumIsA,
64    EnumAsGetters,
65    VariantName,
66    VariantIndexArity,
67    Serialize,
68    Deserialize,
69    Drive,
70    DriveMut,
71)]
72#[charon::rename("Switch")]
73pub enum SwitchTargets {
74    /// Gives the `if` block and the `else` block
75    If(BlockId, BlockId),
76    /// Gives the integer type, a map linking values to switch branches, and the
77    /// otherwise block. Note that matches over enumerations are performed by
78    /// switching over the discriminant, which is an integer.
79    SwitchInt(IntegerTy, Vec<(ScalarValue, BlockId)>, BlockId),
80}
81
82/// A raw terminator: a terminator without meta data.
83#[derive(Debug, Clone, EnumIsA, EnumAsGetters, Serialize, Deserialize, Drive, DriveMut)]
84pub enum RawTerminator {
85    Goto {
86        target: BlockId,
87    },
88    Switch {
89        discr: Operand,
90        targets: SwitchTargets,
91    },
92    Call {
93        call: Call,
94        target: BlockId,
95        on_unwind: BlockId,
96    },
97    /// Handles panics and impossible cases.
98    Abort(AbortKind),
99    Return,
100    UnwindResume,
101}
102
103#[derive(Debug, Clone, Serialize, Deserialize, Drive, DriveMut)]
104pub struct Terminator {
105    pub span: Span,
106    pub content: RawTerminator,
107    /// Comments that precede this terminator.
108    // This is filled in a late pass after all the control-flow manipulation.
109    #[drive(skip)]
110    pub comments_before: Vec<String>,
111}
112
113#[derive(Debug, Clone, Serialize, Deserialize, Drive, DriveMut)]
114#[charon::rename("Block")]
115pub struct BlockData {
116    pub statements: Vec<Statement>,
117    pub terminator: Terminator,
118}
charon_lib/ast/ullbc_ast.rs

charon_lib/ast/
ullbc_ast.rs
