luaur-code-gen 0.1.0

Native (A64/X64) code generation for Luau (Rust).
Documentation 
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use crate::enums::condition_x_64::ConditionX64;
use crate::records::assembly_builder_x_64::AssemblyBuilderX64;
use crate::records::label::Label;

impl AssemblyBuilderX64 {
    pub fn jcc(&mut self, cond: ConditionX64, label: &mut Label) {
        let cc = match cond {
            ConditionX64::Overflow => 0x70,
            ConditionX64::NoOverflow => 0x71,
            ConditionX64::Carry => 0x72,
            ConditionX64::NoCarry => 0x73,
            ConditionX64::Below => 0x72,
            ConditionX64::BelowEqual => 0x76,
            ConditionX64::Above => 0x77,
            ConditionX64::AboveEqual => 0x73,
            ConditionX64::Equal => 0x74,
            ConditionX64::Less => 0x7c,
            ConditionX64::LessEqual => 0x7e,
            ConditionX64::Greater => 0x7f,
            ConditionX64::GreaterEqual => 0x7d,
            ConditionX64::NotBelow => 0x73,
            ConditionX64::NotBelowEqual => 0x77,
            ConditionX64::NotAbove => 0x76,
            ConditionX64::NotAboveEqual => 0x72,
            ConditionX64::NotEqual => 0x75,
            ConditionX64::NotLess => 0x7d,
            ConditionX64::NotLessEqual => 0x7f,
            ConditionX64::NotGreater => 0x7e,
            ConditionX64::NotGreaterEqual => 0x7c,
            ConditionX64::Zero => 0x74,
            ConditionX64::NotZero => 0x75,
            ConditionX64::Parity => 0x7a,
            ConditionX64::NotParity => 0x7b,
            ConditionX64::Count => 0x70,
        };
        // C++ passes `jccTextForCondition[cond]` as the disassembler mnemonic — NOT
        // null, which would `strlen(NULL)` in the log path. Order matches the
        // `ConditionX64` discriminants (same order as `codeForCondition`).
        let jcc_text = [
            c"jo", c"jno", c"jc", c"jnc", c"jb", c"jbe", c"ja", c"jae", c"je", c"jl", c"jle",
            c"jg", c"jge", c"jnb", c"jnbe", c"jna", c"jnae", c"jne", c"jnl", c"jnle", c"jng",
            c"jnge", c"jz", c"jnz", c"jp", c"jnp",
        ];
        let name = jcc_text[cond as usize].as_ptr();

        // C++ passes `codeForCondition[cond]` (the 0-15 condition code); this match
        // holds the full rel8 opcodes (0x70|cc), so `place_jcc` (which does
        // `0x80 | code`) needs just the low-nibble condition code.
        self.place_jcc(name, label, (cc & 0x0F) as u8);
    }
}