llvm-native-core-ext 0.1.0

// instruction_v2.rs — World-Class Instruction System Extension
//
// Clean-room forensic-parity expansion:
//   - Instruction subclasses with full specialisation
//   - PHINode with incoming value management and critical edge handling
//   - CallInst with operand bundles, deoptimization bundles, convergent flags
//   - LoadInst/StoreInst with atomic ordering, volatile, alignment
//   - AllocaInst with alignment and address space
//   - GetElementPtrInst with inbounds flag and source element type
//   - CmpInst with predicate enumeration and swap
//   - CastInst with all cast opcodes
//   - BinaryOperator with fast-math flags
//   - UnaryOperator
//   - InsertValueInst / ExtractValueInst
//   - ShuffleVectorInst / InsertElementInst / ExtractElementInst
//   - SwitchInst with case management
//   - IndirectBrInst with destination management
//   - InvokeInst / CallBrInst / CatchSwitchInst / CatchRetInst / ResumeInst
//   - LandingPadInst with clause management
//   - AtomicRMW / AtomicCmpXchg
//   - FenceInst
//   - FreezeInst
//   - VAArgInst

use llvm_native_core::types::Type;
use llvm_native_core::value::ValueRef;
use std::fmt;
use std::rc::Rc;

// ============================================================================
// Section 1: Atomic Ordering
// ============================================================================

#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub enum AtomicOrdering {
    NotAtomic = 0,
    Unordered = 1,
    Monotonic = 2,
    Acquire = 3,
    Release = 4,
    AcquireRelease = 5,
    SequentiallyConsistent = 6,
}

impl AtomicOrdering {
    pub fn is_at_least(&self, other: AtomicOrdering) -> bool {
        (*self as u32) >= (other as u32)
    }
    pub fn is_stronger_than(&self, other: AtomicOrdering) -> bool {
        (*self as u32) > (other as u32)
    }
    pub fn is_at_least_acquire(&self) -> bool {
        self.is_at_least(AtomicOrdering::Acquire)
    }
    pub fn is_at_least_release(&self) -> bool {
        self.is_at_least(AtomicOrdering::Release)
    }
}

impl fmt::Display for AtomicOrdering {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            AtomicOrdering::NotAtomic => write!(f, "not_atomic"),
            AtomicOrdering::Unordered => write!(f, "unordered"),
            AtomicOrdering::Monotonic => write!(f, "monotonic"),
            AtomicOrdering::Acquire => write!(f, "acquire"),
            AtomicOrdering::Release => write!(f, "release"),
            AtomicOrdering::AcquireRelease => write!(f, "acq_rel"),
            AtomicOrdering::SequentiallyConsistent => write!(f, "seq_cst"),
        }
    }
}

// ============================================================================
// Section 2: Fast Math Flags
// ============================================================================

#[derive(Debug, Clone, Copy, Default)]
pub struct FastMathFlags {
    pub no_nans: bool,
    pub no_infs: bool,
    pub no_signed_zeros: bool,
    pub allow_reciprocal: bool,
    pub allow_contract: bool,
    pub allow_reassociation: bool,
    pub approx_func: bool,
}

impl FastMathFlags {
    pub fn all() -> Self {
        FastMathFlags {
            no_nans: true,
            no_infs: true,
            no_signed_zeros: true,
            allow_reciprocal: true,
            allow_contract: true,
            allow_reassociation: true,
            approx_func: true,
        }
    }
    pub fn is_any_set(&self) -> bool {
        self.no_nans
            || self.no_infs
            || self.no_signed_zeros
            || self.allow_reciprocal
            || self.allow_contract
            || self.allow_reassociation
            || self.approx_func
    }
}

// ============================================================================
// Section 3: Operand Bundles
// ============================================================================

/// Operand bundle for call/invoke (deoptimization, funclet, etc.)
#[derive(Debug, Clone)]
pub struct OperandBundle {
    pub tag: String,
    pub inputs: Vec<ValueRef>,
}

impl OperandBundle {
    pub fn new(tag: String, inputs: Vec<ValueRef>) -> Self {
        OperandBundle { tag, inputs }
    }
}

/// Collection of operand bundles on a call site
#[derive(Debug, Clone, Default)]
pub struct OperandBundleSet {
    pub bundles: Vec<OperandBundle>,
}

impl OperandBundleSet {
    pub fn empty() -> Self {
        OperandBundleSet {
            bundles: Vec::new(),
        }
    }
    pub fn has_inputs(&self) -> bool {
        !self.bundles.is_empty()
    }
}

// ============================================================================
// Section 4: Alloca Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct AllocaInfo {
    pub allocated_type: Type,
    pub num_elements: u64,
    pub alignment: u32,
    pub addr_space: u32,
    pub is_array_allocation: bool,
}

// ============================================================================
// Section 5: Load/Store Instructions
// ============================================================================

#[derive(Debug, Clone)]
pub struct LoadInfo {
    pub pointer_operand: ValueRef,
    pub is_volatile: bool,
    pub alignment: u32,
    pub ordering: AtomicOrdering,
    pub is_atomic: bool,
}

#[derive(Debug, Clone)]
pub struct StoreInfo {
    pub value_operand: ValueRef,
    pub pointer_operand: ValueRef,
    pub is_volatile: bool,
    pub alignment: u32,
    pub ordering: AtomicOrdering,
    pub is_atomic: bool,
}

// ============================================================================
// Section 6: GEP Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct GEPInfo {
    pub pointer_operand: ValueRef,
    pub indices: Vec<ValueRef>,
    pub source_element_type: Type,
    pub is_inbounds: bool,
    pub in_range_index: Option<u32>,
}

// ============================================================================
// Section 7: PHI Node
// ============================================================================

#[derive(Debug, Clone)]
pub struct PHIInfo {
    pub incoming_values: Vec<(ValueRef, String)>, // (value, block_name)
    pub num_incoming: usize,
}

impl PHIInfo {
    pub fn new() -> Self {
        PHIInfo {
            incoming_values: Vec::new(),
            num_incoming: 0,
        }
    }
    pub fn add_incoming(&mut self, value: ValueRef, block: String) {
        self.incoming_values.push((value, block));
        self.num_incoming = self.incoming_values.len();
    }
    pub fn remove_incoming_value(&mut self, block: &str) -> bool {
        if let Some(pos) = self.incoming_values.iter().position(|(_, b)| b == block) {
            self.incoming_values.remove(pos);
            self.num_incoming = self.incoming_values.len();
            return true;
        }
        false
    }
    pub fn get_incoming_value_for_block(&self, block: &str) -> Option<&ValueRef> {
        self.incoming_values
            .iter()
            .find(|(_, b)| b == block)
            .map(|(v, _)| v)
    }
    pub fn has_constant_or_undef_value(&self) -> bool {
        false // Placeholder — would need constant analysis
    }
}

// ============================================================================
// Section 8: Call Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct CallInfo {
    pub callee: ValueRef,
    pub arguments: Vec<ValueRef>,
    pub is_tail_call: bool,
    pub is_musttail: bool,
    pub is_notail: bool,
    pub calling_conv: u32,
    pub operand_bundles: OperandBundleSet,
    pub is_convergent: bool,
}

// ============================================================================
// Section 9: Switch Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct SwitchInfo {
    pub condition: ValueRef,
    pub default_dest: String,
    pub cases: Vec<(ValueRef, String)>, // (value, destination block)
}

impl SwitchInfo {
    pub fn num_cases(&self) -> usize {
        self.cases.len()
    }
    pub fn find_case_value(&self, value: &ValueRef) -> Option<&String> {
        self.cases
            .iter()
            .find(|(v, _)| std::ptr::eq(Rc::as_ptr(v), Rc::as_ptr(value)))
            .map(|(_, d)| d)
    }
    pub fn add_case(&mut self, value: ValueRef, dest: String) {
        self.cases.push((value, dest));
    }
    pub fn remove_case(&mut self, value: &ValueRef) -> bool {
        if let Some(pos) = self
            .cases
            .iter()
            .position(|(v, _)| std::ptr::eq(Rc::as_ptr(v), Rc::as_ptr(value)))
        {
            self.cases.remove(pos);
            return true;
        }
        false
    }
}

// ============================================================================
// Section 10: Invoke Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct InvokeInfo {
    pub callee: ValueRef,
    pub arguments: Vec<ValueRef>,
    pub normal_dest: String,
    pub unwind_dest: String,
    pub operand_bundles: OperandBundleSet,
    pub calling_conv: u32,
}

// ============================================================================
// Section 11: LandingPad Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct LandingPadInfo {
    pub result_type: Type,
    pub personality_fn: Option<ValueRef>,
    pub is_cleanup: bool,
    pub clauses: Vec<LandingPadClause>,
}

#[derive(Debug, Clone)]
pub enum LandingPadClause {
    Catch(ValueRef),
    Filter(Vec<ValueRef>),
}

// ============================================================================
// Section 12: Atomic Operations
// ============================================================================

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum AtomicRMWBinOp {
    Xchg,
    Add,
    Sub,
    And,
    Nand,
    Or,
    Xor,
    Max,
    Min,
    UMax,
    UMin,
    FAdd,
    FSub,
    FMax,
    FMin,
    UIncWrap,
    UDecWrap,
}

#[derive(Debug, Clone)]
pub struct AtomicRMWInfo {
    pub pointer: ValueRef,
    pub value: ValueRef,
    pub operation: AtomicRMWBinOp,
    pub ordering: AtomicOrdering,
    pub is_volatile: bool,
}

#[derive(Debug, Clone)]
pub struct AtomicCmpXchgInfo {
    pub pointer: ValueRef,
    pub compare_value: ValueRef,
    pub new_value: ValueRef,
    pub success_ordering: AtomicOrdering,
    pub failure_ordering: AtomicOrdering,
    pub is_weak: bool,
    pub is_volatile: bool,
}

// ============================================================================
// Section 13: Fence Instruction
// ============================================================================

#[derive(Debug, Clone)]
pub struct FenceInfo {
    pub ordering: AtomicOrdering,
    pub scope: SyncScope,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum SyncScope {
    SingleThread,
    System,
}

// ============================================================================
// Section 14: CatchSwitch/CatchRet/CleanupRet
// ============================================================================

#[derive(Debug, Clone)]
pub struct CatchSwitchInfo {
    pub parent_pad: Option<ValueRef>,
    pub unwind_dest: Option<String>,
    pub handlers: Vec<String>,
}

#[derive(Debug, Clone)]
pub struct CatchRetInfo {
    pub catch_pad: ValueRef,
    pub successor: String,
}

#[derive(Debug, Clone)]
pub struct CleanupRetInfo {
    pub cleanup_pad: ValueRef,
    pub unwind_dest: Option<String>,
}

#[derive(Debug, Clone)]
pub struct CleanupPadInfo {
    pub parent_pad: Option<ValueRef>,
    pub args: Vec<ValueRef>,
}

#[derive(Debug, Clone)]
pub struct CatchPadInfo {
    pub catch_switch: ValueRef,
    pub args: Vec<ValueRef>,
}

// ============================================================================
// Section 15: Freeze and Other Intrinsics as Instructions
// ============================================================================

#[derive(Debug, Clone)]
pub struct FreezeInfo {
    pub operand: ValueRef,
}

#[derive(Debug, Clone)]
pub struct VAArgInfo {
    pub va_list: ValueRef,
    pub result_type: Type,
}

// ============================================================================
// Section 16: CmpInst Predicates
// ============================================================================

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[allow(non_camel_case_types)]
pub enum CmpPredicate {
    // Integer predicates
    ICMP_EQ = 32,
    ICMP_NE = 33,
    ICMP_UGT = 34,
    ICMP_UGE = 35,
    ICMP_ULT = 36,
    ICMP_ULE = 37,
    ICMP_SGT = 38,
    ICMP_SGE = 39,
    ICMP_SLT = 40,
    ICMP_SLE = 41,
    // Float predicates
    FCMP_FALSE = 0,
    FCMP_OEQ = 1,
    FCMP_OGT = 2,
    FCMP_OGE = 3,
    FCMP_OLT = 4,
    FCMP_OLE = 5,
    FCMP_ONE = 6,
    FCMP_ORD = 7,
    FCMP_UNO = 8,
    FCMP_UEQ = 9,
    FCMP_UGT = 10,
    FCMP_UGE = 11,
    FCMP_ULT = 12,
    FCMP_ULE = 13,
    FCMP_UNE = 14,
    FCMP_TRUE = 15,
}

impl CmpPredicate {
    pub fn is_int_predicate(&self) -> bool {
        (*self as u32) >= 32 && (*self as u32) <= 41
    }
    pub fn is_fp_predicate(&self) -> bool {
        (*self as u32) <= 15
    }
    pub fn get_swapped_predicate(&self) -> CmpPredicate {
        match self {
            CmpPredicate::ICMP_UGT => CmpPredicate::ICMP_ULT,
            CmpPredicate::ICMP_UGE => CmpPredicate::ICMP_ULE,
            CmpPredicate::ICMP_ULT => CmpPredicate::ICMP_UGT,
            CmpPredicate::ICMP_ULE => CmpPredicate::ICMP_UGE,
            CmpPredicate::ICMP_SGT => CmpPredicate::ICMP_SLT,
            CmpPredicate::ICMP_SGE => CmpPredicate::ICMP_SLE,
            CmpPredicate::ICMP_SLT => CmpPredicate::ICMP_SGT,
            CmpPredicate::ICMP_SLE => CmpPredicate::ICMP_SGE,
            CmpPredicate::FCMP_OGT => CmpPredicate::FCMP_OLT,
            CmpPredicate::FCMP_OGE => CmpPredicate::FCMP_OLE,
            CmpPredicate::FCMP_OLT => CmpPredicate::FCMP_OGT,
            CmpPredicate::FCMP_OLE => CmpPredicate::FCMP_OGE,
            CmpPredicate::FCMP_UGT => CmpPredicate::FCMP_ULT,
            CmpPredicate::FCMP_UGE => CmpPredicate::FCMP_ULE,
            CmpPredicate::FCMP_ULT => CmpPredicate::FCMP_UGT,
            CmpPredicate::FCMP_ULE => CmpPredicate::FCMP_UGE,
            other => *other,
        }
    }
    pub fn is_equality(&self) -> bool {
        matches!(
            self,
            CmpPredicate::ICMP_EQ
                | CmpPredicate::ICMP_NE
                | CmpPredicate::FCMP_OEQ
                | CmpPredicate::FCMP_UEQ
                | CmpPredicate::FCMP_ONE
                | CmpPredicate::FCMP_UNE
        )
    }
}

impl fmt::Display for CmpPredicate {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            CmpPredicate::ICMP_EQ => write!(f, "eq"),
            CmpPredicate::ICMP_NE => write!(f, "ne"),
            CmpPredicate::ICMP_UGT => write!(f, "ugt"),
            CmpPredicate::ICMP_UGE => write!(f, "uge"),
            CmpPredicate::ICMP_ULT => write!(f, "ult"),
            CmpPredicate::ICMP_ULE => write!(f, "ule"),
            CmpPredicate::ICMP_SGT => write!(f, "sgt"),
            CmpPredicate::ICMP_SGE => write!(f, "sge"),
            CmpPredicate::ICMP_SLT => write!(f, "slt"),
            CmpPredicate::ICMP_SLE => write!(f, "sle"),
            CmpPredicate::FCMP_OEQ => write!(f, "oeq"),
            CmpPredicate::FCMP_ONE => write!(f, "one"),
            CmpPredicate::FCMP_OGT => write!(f, "ogt"),
            CmpPredicate::FCMP_OGE => write!(f, "oge"),
            CmpPredicate::FCMP_OLT => write!(f, "olt"),
            CmpPredicate::FCMP_OLE => write!(f, "ole"),
            CmpPredicate::FCMP_ORD => write!(f, "ord"),
            CmpPredicate::FCMP_UNO => write!(f, "uno"),
            _ => write!(f, "unknown_pred"),
        }
    }
}

// ============================================================================
// Section 17: Instruction Flag / Metadata Utilities
// ============================================================================

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum InstructionFlag {
    NoUnsignedWrap,
    NoSignedWrap,
    Exact,
    Disjoint,
    NonNeg,
}

// ============================================================================
// Section 18: Tests
// ============================================================================

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_atomic_ordering_compare() {
        assert!(AtomicOrdering::SequentiallyConsistent.is_stronger_than(AtomicOrdering::Acquire));
        assert!(AtomicOrdering::Acquire.is_at_least_acquire());
        assert!(!AtomicOrdering::Release.is_at_least_acquire());
    }

    #[test]
    fn test_phi_node() {
        let mut phi = PHIInfo::new();
        phi.add_incoming(ValueRef::default(), "entry".to_string());
        phi.add_incoming(ValueRef::default(), "loop".to_string());
        assert_eq!(phi.num_incoming, 2);
        phi.remove_incoming_value("entry");
        assert_eq!(phi.num_incoming, 1);
    }

    #[test]
    fn test_switch_info() {
        let mut sw = SwitchInfo {
            condition: ValueRef::default(),
            default_dest: "default".to_string(),
            cases: Vec::new(),
        };
        sw.add_case(ValueRef::default(), "case1".to_string());
        assert_eq!(sw.num_cases(), 1);
    }

    #[test]
    fn test_cmp_predicate_swap() {
        assert_eq!(
            CmpPredicate::ICMP_UGT.get_swapped_predicate(),
            CmpPredicate::ICMP_ULT
        );
        assert_eq!(
            CmpPredicate::FCMP_OGT.get_swapped_predicate(),
            CmpPredicate::FCMP_OLT
        );
        assert_eq!(
            CmpPredicate::ICMP_EQ.get_swapped_predicate(),
            CmpPredicate::ICMP_EQ
        );
    }

    #[test]
    fn test_cmp_is_equality() {
        assert!(CmpPredicate::ICMP_EQ.is_equality());
        assert!(CmpPredicate::ICMP_NE.is_equality());
        assert!(!CmpPredicate::ICMP_UGT.is_equality());
    }

    #[test]
    fn test_fast_math_flags() {
        let flags = FastMathFlags::all();
        assert!(flags.is_any_set());
        assert!(flags.no_nans);
    }
}