aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/llvm/value.rs
blob: 219c85587e1c47f08912a0d801a2b23069d8c9f6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
use llvm_sys::{
    analysis::{LLVMVerifierFailureAction, LLVMVerifyFunction},
    core::{
        LLVMAppendExistingBasicBlock, LLVMCountBasicBlocks, LLVMCountParams, LLVMDumpValue,
        LLVMGetParam, LLVMGetReturnType, LLVMGetValueKind, LLVMGetValueName2, LLVMSetValueName2,
        LLVMTypeOf,
    },
    prelude::LLVMValueRef,
    LLVMTypeKind, LLVMValueKind,
};

use std::ffi::CStr;
use std::marker::PhantomData;
use std::ops::Deref;

use super::BasicBlock;
use super::Type;

/// Wrapper for a LLVM Value Reference.
#[derive(Copy, Clone)]
#[repr(transparent)]
pub struct Value<'llvm>(LLVMValueRef, PhantomData<&'llvm ()>);

impl<'llvm> Value<'llvm> {
    /// Create a new Value instance.
    ///
    /// # Panics
    ///
    /// Panics if `value_ref` is a null pointer.
    pub(super) fn new(value_ref: LLVMValueRef) -> Self {
        assert!(!value_ref.is_null());
        Value(value_ref, PhantomData)
    }

    /// Get the raw LLVM value reference.
    #[inline]
    pub(super) fn value_ref(&self) -> LLVMValueRef {
        self.0
    }

    /// Get the LLVM value kind for the given value reference.
    pub(super) fn kind(&self) -> LLVMValueKind {
        unsafe { LLVMGetValueKind(self.value_ref()) }
    }

    /// Dump the LLVM Value to stdout.
    pub fn dump(&self) {
        unsafe { LLVMDumpValue(self.value_ref()) };
    }

    /// Get a type reference representing for the given value reference.
    ///
    /// # Panics
    ///
    /// Panics if LLVM API returns a `null` pointer.
    pub fn type_of(&self) -> Type<'llvm> {
        let type_ref = unsafe { LLVMTypeOf(self.value_ref()) };
        Type::new(type_ref)
    }

    /// Set the name for the given value reference.
    ///
    /// # Panics
    ///
    /// Panics if LLVM API returns a `null` pointer.
    pub fn set_name(&self, name: &str) {
        unsafe { LLVMSetValueName2(self.value_ref(), name.as_ptr().cast(), name.len()) };
    }

    /// Get the name for the given value reference.
    ///
    /// # Panics
    ///
    /// Panics if LLVM API returns a `null` pointer.
    pub fn get_name(&self) -> &'llvm str {
        let name = unsafe {
            let mut len: libc::size_t = 0;
            let name = LLVMGetValueName2(self.0, &mut len as _);
            assert!(!name.is_null());

            CStr::from_ptr(name)
        };

        // TODO: Does this string live for the time of the LLVM context?!
        name.to_str()
            .expect("Expected valid UTF8 string from LLVM API")
    }

    /// Check if value is of `f64` type.
    pub fn is_f64(&self) -> bool {
        self.type_of().kind() == LLVMTypeKind::LLVMDoubleTypeKind
    }

    /// Check if value is of integer type.
    pub fn is_int(&self) -> bool {
        self.type_of().kind() == LLVMTypeKind::LLVMIntegerTypeKind
    }
}

/// Wrapper for a LLVM Value Reference specialized for contexts where function values are needed.
#[derive(Copy, Clone)]
#[repr(transparent)]
pub struct FnValue<'llvm>(Value<'llvm>);

impl<'llvm> Deref for FnValue<'llvm> {
    type Target = Value<'llvm>;
    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl<'llvm> FnValue<'llvm> {
    /// Create a new FnValue instance.
    ///
    /// # Panics
    ///
    /// Panics if `value_ref` is a null pointer.
    pub(super) fn new(value_ref: LLVMValueRef) -> Self {
        let value = Value::new(value_ref);
        debug_assert_eq!(
            value.kind(),
            LLVMValueKind::LLVMFunctionValueKind,
            "Expected a fn value when constructing FnValue!"
        );

        FnValue(value)
    }

    /// Get a type reference representing the return value of the given function value.
    ///
    /// # Panics
    ///
    /// Panics if LLVM API returns a `null` pointer.
    pub fn ret_type(&self) -> Type<'llvm> {
        let type_ref = unsafe { LLVMGetReturnType(LLVMTypeOf(self.value_ref())) };
        Type::new(type_ref)
    }

    /// Get the number of function arguments for the given function value.
    pub fn args(&self) -> usize {
        unsafe { LLVMCountParams(self.value_ref()) as usize }
    }

    /// Get a value reference for the function argument at index `idx`.
    ///
    /// # Panics
    ///
    /// Panics if LLVM API returns a `null` pointer or indexed out of bounds.
    pub fn arg(&self, idx: usize) -> Value<'llvm> {
        assert!(idx < self.args());

        let value_ref = unsafe { LLVMGetParam(self.value_ref(), idx as libc::c_uint) };
        Value::new(value_ref)
    }

    /// Get the number of Basic Blocks for the given function value.
    pub fn basic_blocks(&self) -> usize {
        unsafe { LLVMCountBasicBlocks(self.value_ref()) as usize }
    }

    /// Append a Basic Block to the end of the function value.
    pub fn append_basic_block(&self, bb: BasicBlock<'llvm>) {
        unsafe {
            LLVMAppendExistingBasicBlock(self.value_ref(), bb.bb_ref());
        }
    }

    /// Verify that the given function is valid.
    pub fn verify(&self) -> bool {
        unsafe {
            LLVMVerifyFunction(
                self.value_ref(),
                LLVMVerifierFailureAction::LLVMPrintMessageAction,
            ) == 0
        }
    }
}