summaryrefslogtreecommitdiffstats
path: root/compiler/rustc_codegen_gcc/src/declare.rs
blob: a619e2f77125243a062ca7617c098f7a2ca562c7 (plain)
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
use gccjit::{Function, FunctionType, GlobalKind, LValue, RValue, Type};
use rustc_codegen_ssa::traits::BaseTypeMethods;
use rustc_middle::ty::Ty;
use rustc_span::Symbol;
use rustc_target::abi::call::FnAbi;

use crate::abi::FnAbiGccExt;
use crate::context::CodegenCx;
use crate::intrinsic::llvm;

impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
    pub fn get_or_insert_global(&self, name: &str, ty: Type<'gcc>, is_tls: bool, link_section: Option<Symbol>) -> LValue<'gcc> {
        if self.globals.borrow().contains_key(name) {
            let typ = self.globals.borrow()[name].get_type();
            let global = self.context.new_global(None, GlobalKind::Imported, typ, name);
            if is_tls {
                global.set_tls_model(self.tls_model);
            }
            if let Some(link_section) = link_section {
                global.set_link_section(link_section.as_str());
            }
            global
        }
        else {
            self.declare_global(name, ty, GlobalKind::Exported, is_tls, link_section)
        }
    }

    pub fn declare_unnamed_global(&self, ty: Type<'gcc>) -> LValue<'gcc> {
        let name = self.generate_local_symbol_name("global");
        self.context.new_global(None, GlobalKind::Internal, ty, &name)
    }

    pub fn declare_global_with_linkage(&self, name: &str, ty: Type<'gcc>, linkage: GlobalKind) -> LValue<'gcc> {
        let global = self.context.new_global(None, linkage, ty, name);
        let global_address = global.get_address(None);
        self.globals.borrow_mut().insert(name.to_string(), global_address);
        global
    }

    /*pub fn declare_func(&self, name: &str, return_type: Type<'gcc>, params: &[Type<'gcc>], variadic: bool) -> RValue<'gcc> {
        self.linkage.set(FunctionType::Exported);
        let func = declare_raw_fn(self, name, () /*llvm::CCallConv*/, return_type, params, variadic);
        // FIXME(antoyo): this is a wrong cast. That requires changing the compiler API.
        unsafe { std::mem::transmute(func) }
    }*/

    pub fn declare_global(&self, name: &str, ty: Type<'gcc>, global_kind: GlobalKind, is_tls: bool, link_section: Option<Symbol>) -> LValue<'gcc> {
        let global = self.context.new_global(None, global_kind, ty, name);
        if is_tls {
            global.set_tls_model(self.tls_model);
        }
        if let Some(link_section) = link_section {
            global.set_link_section(link_section.as_str());
        }
        let global_address = global.get_address(None);
        self.globals.borrow_mut().insert(name.to_string(), global_address);
        global
    }

    pub fn declare_private_global(&self, name: &str, ty: Type<'gcc>) -> LValue<'gcc> {
        let global = self.context.new_global(None, GlobalKind::Internal, ty, name);
        let global_address = global.get_address(None);
        self.globals.borrow_mut().insert(name.to_string(), global_address);
        global
    }

    pub fn declare_cfn(&self, name: &str, _fn_type: Type<'gcc>) -> RValue<'gcc> {
        // TODO(antoyo): use the fn_type parameter.
        let const_string = self.context.new_type::<u8>().make_pointer().make_pointer();
        let return_type = self.type_i32();
        let variadic = false;
        self.linkage.set(FunctionType::Exported);
        let func = declare_raw_fn(self, name, () /*llvm::CCallConv*/, return_type, &[self.type_i32(), const_string], variadic);
        // NOTE: it is needed to set the current_func here as well, because get_fn() is not called
        // for the main function.
        *self.current_func.borrow_mut() = Some(func);
        // FIXME(antoyo): this is a wrong cast. That requires changing the compiler API.
        unsafe { std::mem::transmute(func) }
    }

    pub fn declare_fn(&self, name: &str, fn_abi: &FnAbi<'tcx, Ty<'tcx>>) -> RValue<'gcc> {
        let (return_type, params, variadic, on_stack_param_indices) = fn_abi.gcc_type(self);
        let func = declare_raw_fn(self, name, () /*fn_abi.llvm_cconv()*/, return_type, &params, variadic);
        self.on_stack_function_params.borrow_mut().insert(func, on_stack_param_indices);
        // FIXME(antoyo): this is a wrong cast. That requires changing the compiler API.
        unsafe { std::mem::transmute(func) }
    }

    pub fn define_global(&self, name: &str, ty: Type<'gcc>, is_tls: bool, link_section: Option<Symbol>) -> LValue<'gcc> {
        self.get_or_insert_global(name, ty, is_tls, link_section)
    }

    pub fn get_declared_value(&self, name: &str) -> Option<RValue<'gcc>> {
        // TODO(antoyo): use a different field than globals, because this seems to return a function?
        self.globals.borrow().get(name).cloned()
    }
}

/// Declare a function.
///
/// If there’s a value with the same name already declared, the function will
/// update the declaration and return existing Value instead.
fn declare_raw_fn<'gcc>(cx: &CodegenCx<'gcc, '_>, name: &str, _callconv: () /*llvm::CallConv*/, return_type: Type<'gcc>, param_types: &[Type<'gcc>], variadic: bool) -> Function<'gcc> {
    if name.starts_with("llvm.") {
        let intrinsic = llvm::intrinsic(name, cx);
        cx.intrinsics.borrow_mut().insert(name.to_string(), intrinsic);
        return intrinsic;
    }
    let func =
        if cx.functions.borrow().contains_key(name) {
            cx.functions.borrow()[name]
        }
        else {
            let params: Vec<_> = param_types.into_iter().enumerate()
                .map(|(index, param)| cx.context.new_parameter(None, *param, &format!("param{}", index))) // TODO(antoyo): set name.
                .collect();
            let func = cx.context.new_function(None, cx.linkage.get(), return_type, &params, mangle_name(name), variadic);
            cx.functions.borrow_mut().insert(name.to_string(), func);
            func
        };

    // TODO(antoyo): set function calling convention.
    // TODO(antoyo): set unnamed address.
    // TODO(antoyo): set no red zone function attribute.
    // TODO(antoyo): set attributes for optimisation.
    // TODO(antoyo): set attributes for non lazy bind.

    // FIXME(antoyo): invalid cast.
    func
}

// FIXME(antoyo): this is a hack because libgccjit currently only supports alpha, num and _.
// Unsupported characters: `$` and `.`.
pub fn mangle_name(name: &str) -> String {
    name.replace(|char: char| {
        if !char.is_alphanumeric() && char != '_' {
            debug_assert!("$.".contains(char), "Unsupported char in function name: {}", char);
            true
        }
        else {
            false
        }
    }, "_")
}