luaur-code-gen 0.1.0

Native (A64/X64) code generation for Luau (Rust).
Documentation 
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use crate::enums::size_x_64::SizeX64;
use crate::records::operand_x_64::OperandX64;
use crate::records::register_x_64::RegisterX64;
use luaur_vm::type_aliases::t_value::TValue;

/// Returns an operand for the value field of a constant TValue in the constant array.
///
/// C++: qword[rConstants + ki * sizeof(TValue) + offsetof(TValue, value)]
///
/// In Luau x64 JIT:
/// - rConstants is a base pointer to the constant array
/// - sizeof(TValue) is 16 (2^kTValueSizeLog2, where kTValueSizeLog2 = 4)
/// - offsetof(TValue, value) is 0 (Value is the first member of the union)
/// - The operand uses qword size for the full TValue value field access
#[inline]
pub fn luau_constant_value(ki: i32) -> OperandX64 {
    let tvalue_size = core::mem::size_of::<TValue>() as i32;
    let value_offset = 0;

    // NOTE: rConstants is represented as a memory base register operand, not as a RegisterX64::rconstants associated constant.
    OperandX64::operand_x_64_size_x_64_register_x_64_u8_register_x_64_i32(
        SizeX64::qword,
        RegisterX64::noreg,
        0,
        RegisterX64::rbp,
        ki * tvalue_size + value_offset,
    )
}