metal2vulkan 0.1.0

Translate Metal AIR / LLVM IR to Vulkan SPIR-V with a native Rust emitter
Documentation 
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

use super::*;

/// Replace native-emitter buffer-address facts with loads from one reflected address-table
/// StorageBuffer. The runtime fills table[Metal buffer location] with vkGetBufferDeviceAddress.
pub(in crate::passes) fn lower_buffer_address_facts(
    ctx: &mut Ctx,
    entry_idx: usize,
    kern: Option<&KernMeta>,
) -> Result<(), String> {
    let address_words = ctx
        .emit_sidecar
        .buffer_address_words
        .iter()
        .map(|fact| (fact.id, (fact.param_index, fact.component)))
        .collect::<HashMap<_, _>>();
    if address_words.is_empty() {
        return Ok(());
    }
    let kern = kern.ok_or("buffer-address facts require kernel metadata")?;
    let mut locations = HashMap::new();
    for (id, (param_index, component)) in &address_words {
        let Some(KernRole::Buffer(location)) = kern.role_of(*param_index) else {
            return Err(format!(
                "buffer-address fact {id} references non-buffer kernel parameter {param_index}"
            ));
        };
        locations.insert(*id, (*location, *component));
    }

    let uint_ty = ctx.ty_uint();
    let vec_ty = ctx.ty_vec_uint(2);
    let array_ty = ctx.module.fresh_id();
    ctx.new_globals.push(type_inst(
        Op::TypeRuntimeArray,
        array_ty,
        vec![Operand::IdRef(vec_ty)],
    ));
    ctx.module.annotations.push(Instruction::new(
        Op::Decorate,
        None,
        None,
        vec![
            Operand::IdRef(array_ty),
            Operand::Decoration(Decoration::ArrayStride),
            Operand::LiteralBit32(std::mem::size_of::<u64>() as u32),
        ],
    ));
    let block_ty = ctx.module.fresh_id();
    ctx.new_globals.push(type_inst(
        Op::TypeStruct,
        block_ty,
        vec![Operand::IdRef(array_ty)],
    ));
    ctx.module.annotations.push(Instruction::new(
        Op::MemberDecorate,
        None,
        None,
        vec![
            Operand::IdRef(block_ty),
            Operand::LiteralBit32(0),
            Operand::Decoration(Decoration::Offset),
            Operand::LiteralBit32(0),
        ],
    ));
    ctx.module.annotations.push(Instruction::new(
        Op::Decorate,
        None,
        None,
        vec![
            Operand::IdRef(block_ty),
            Operand::Decoration(Decoration::Block),
        ],
    ));
    let block_ptr_ty = ctx.ty_ptr(StorageClass::StorageBuffer, block_ty);
    let uint_ptr_ty = ctx.ty_ptr(StorageClass::StorageBuffer, uint_ty);
    let table = ctx.module.fresh_id();
    ctx.new_globals.push(Instruction::new(
        Op::Variable,
        Some(block_ptr_ty),
        Some(table),
        vec![Operand::StorageClass(StorageClass::StorageBuffer)],
    ));
    let max_binding = ctx
        .module
        .annotations
        .iter()
        .filter(|inst| {
            inst.class.opcode == Op::Decorate
                && inst.operands.get(1) == Some(&Operand::Decoration(Decoration::Binding))
        })
        .filter_map(|inst| match inst.operands.get(2) {
            Some(Operand::LiteralBit32(binding)) => Some(*binding),
            _ => None,
        })
        .max()
        .unwrap_or(0)
        .saturating_add(1);
    decorate_binding(&mut ctx.module, table, max_binding);
    ctx.interface_buffer_var(table);

    let zero = ctx.const_uint(0);
    let location_constants = locations
        .values()
        .map(|(location, _)| *location)
        .collect::<HashSet<_>>()
        .into_iter()
        .map(|location| (location, ctx.const_uint(location)))
        .collect::<HashMap<_, _>>();
    let component_constants = [ctx.const_uint(0), ctx.const_uint(1)];
    let block_count = ctx.module.functions[entry_idx].blocks.len();
    for block_index in 0..block_count {
        let instructions =
            std::mem::take(&mut ctx.module.functions[entry_idx].blocks[block_index].instructions);
        let mut rewritten = Vec::with_capacity(instructions.len());
        for inst in instructions {
            let Some(result) = inst.result_id else {
                rewritten.push(inst);
                continue;
            };
            let Some((location, component)) = locations.get(&result).copied() else {
                rewritten.push(inst);
                continue;
            };
            let pointer = ctx.module.fresh_id();
            rewritten.push(Instruction::new(
                Op::AccessChain,
                Some(uint_ptr_ty),
                Some(pointer),
                vec![
                    Operand::IdRef(table),
                    Operand::IdRef(zero),
                    Operand::IdRef(location_constants[&location]),
                    Operand::IdRef(component_constants[component as usize]),
                ],
            ));
            rewritten.push(Instruction::new(
                Op::Load,
                Some(uint_ty),
                Some(result),
                vec![Operand::IdRef(pointer)],
            ));
        }
        ctx.module.functions[entry_idx].blocks[block_index].instructions = rewritten;
    }
    ctx.emit_sidecar.buffer_address_words.clear();
    Ok(())
}