diff --git a/ptx/src/pass/emit_llvm.rs b/ptx/src/pass/emit_llvm.rs
index 235ad7d..65ab918 100644
--- a/ptx/src/pass/emit_llvm.rs
+++ b/ptx/src/pass/emit_llvm.rs
@@ -436,9 +436,10 @@ impl<'a, 'input> MethodEmitContext<'a, 'input> {
             ast::Instruction::Bfi { data, arguments } => todo!(),
             ast::Instruction::PrmtSlow { arguments } => todo!(),
             ast::Instruction::Prmt { data, arguments } => todo!(),
-            ast::Instruction::Activemask { arguments } => todo!(),
             ast::Instruction::Membar { data } => todo!(),
             ast::Instruction::Trap {} => todo!(),
+            // replaced by a function call
+            ast::Instruction::Activemask { arguments } => return Err(error_unreachable()),
         }
     }
 
@@ -478,7 +479,20 @@ impl<'a, 'input> MethodEmitContext<'a, 'input> {
     fn emit_conversion(&mut self, conversion: ImplicitConversion) -> Result<(), TranslateError> {
         let builder = self.builder;
         match conversion.kind {
-            ConversionKind::Default => todo!(),
+            ConversionKind::Default => {
+                let from_layout = conversion.from_type.layout();
+                let to_layout = conversion.to_type.layout();
+                if from_layout.size() == to_layout.size() {
+                    let src = self.resolver.value(conversion.src)?;
+                    let type_ = get_type(self.context, &conversion.to_type)?;
+                    self.resolver.with_result(conversion.dst, |dst| unsafe {
+                        LLVMBuildBitCast(builder, src, type_, dst)
+                    });
+                    Ok(())
+                } else {
+                    todo!()
+                }
+            },
             ConversionKind::SignExtend => todo!(),
             ConversionKind::BitToPtr => {
                 let src = self.resolver.value(conversion.src)?;
diff --git a/ptx/src/pass/mod.rs b/ptx/src/pass/mod.rs
index 7ba9ed0..ff7e2ad 100644
--- a/ptx/src/pass/mod.rs
+++ b/ptx/src/pass/mod.rs
@@ -37,6 +37,7 @@ mod normalize_identifiers2;
 mod normalize_labels;
 mod normalize_predicates;
 mod normalize_predicates2;
+mod replace_instructions_with_function_calls;
 mod resolve_function_pointers;
 
 static ZLUDA_PTX_IMPL: &'static [u8] = include_bytes!("../../lib/zluda_ptx_impl.bc");
@@ -90,6 +91,7 @@ pub fn to_llvm_module2<'input>(ast: ast::Module<'input>) -> Result<Module, Trans
     let directives = deparamize_functions::run(&mut flat_resolver, directives)?;
     let directives = insert_explicit_load_store::run(&mut flat_resolver, directives)?;
     let directives = insert_implicit_conversions2::run(&mut flat_resolver, directives)?;
+    let directives = replace_instructions_with_function_calls::run(&mut flat_resolver, directives)?;
     let directives = hoist_globals::run(directives)?;
     let llvm_ir = emit_llvm::run(flat_resolver, directives)?;
     Ok(Module {
diff --git a/ptx/src/pass/replace_instructions_with_function_calls.rs b/ptx/src/pass/replace_instructions_with_function_calls.rs
new file mode 100644
index 0000000..30ff75d
--- /dev/null
+++ b/ptx/src/pass/replace_instructions_with_function_calls.rs
@@ -0,0 +1,179 @@
+use super::*;
+
+pub(super) fn run<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    directives: Vec<Directive2<'input, ast::Instruction<SpirvWord>, SpirvWord>>,
+) -> Result<Vec<Directive2<'input, ast::Instruction<SpirvWord>, SpirvWord>>, TranslateError> {
+    let mut fn_declarations = FxHashMap::default();
+    let remapped_directives = directives
+        .into_iter()
+        .map(|directive| run_directive(resolver, &mut fn_declarations, directive))
+        .collect::<Result<Vec<_>, _>>()?;
+    let mut result = fn_declarations
+        .into_iter()
+        .map(|(_, (return_arguments, name, input_arguments))| {
+            Directive2::Method(Function2 {
+                func_decl: ast::MethodDeclaration {
+                    return_arguments,
+                    name: ast::MethodName::Func(name),
+                    input_arguments,
+                    shared_mem: None,
+                },
+                globals: Vec::new(),
+                body: None,
+                import_as: None,
+                tuning: Vec::new(),
+                linkage: ast::LinkingDirective::EXTERN,
+            })
+        })
+        .collect::<Vec<_>>();
+    result.extend(remapped_directives);
+    Ok(result)
+}
+
+fn run_directive<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    fn_declarations: &mut FxHashMap<
+        Cow<'input, str>,
+        (
+            Vec<ast::Variable<SpirvWord>>,
+            SpirvWord,
+            Vec<ast::Variable<SpirvWord>>,
+        ),
+    >,
+    directive: Directive2<'input, ast::Instruction<SpirvWord>, SpirvWord>,
+) -> Result<Directive2<'input, ast::Instruction<SpirvWord>, SpirvWord>, TranslateError> {
+    Ok(match directive {
+        var @ Directive2::Variable(..) => var,
+        Directive2::Method(mut method) => {
+            method.body = method
+                .body
+                .map(|statements| run_statements(resolver, fn_declarations, statements))
+                .transpose()?;
+            Directive2::Method(method)
+        }
+    })
+}
+
+fn run_statements<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    fn_declarations: &mut FxHashMap<
+        Cow<'input, str>,
+        (
+            Vec<ast::Variable<SpirvWord>>,
+            SpirvWord,
+            Vec<ast::Variable<SpirvWord>>,
+        ),
+    >,
+    statements: Vec<Statement<ast::Instruction<SpirvWord>, SpirvWord>>,
+) -> Result<Vec<Statement<ast::Instruction<SpirvWord>, SpirvWord>>, TranslateError> {
+    statements
+        .into_iter()
+        .map(|statement| {
+            Ok(match statement {
+                Statement::Instruction(instruction) => {
+                    Statement::Instruction(run_instruction(resolver, fn_declarations, instruction)?)
+                }
+                s => s,
+            })
+        })
+        .collect::<Result<Vec<_>, _>>()
+}
+
+fn run_instruction<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    fn_declarations: &mut FxHashMap<
+        Cow<'input, str>,
+        (
+            Vec<ast::Variable<SpirvWord>>,
+            SpirvWord,
+            Vec<ast::Variable<SpirvWord>>,
+        ),
+    >,
+    instruction: ptx_parser::Instruction<SpirvWord>,
+) -> Result<ptx_parser::Instruction<SpirvWord>, TranslateError> {
+    Ok(match instruction {
+        i @ ptx_parser::Instruction::Activemask { .. } => {
+            to_call(resolver, fn_declarations, "activemask".into(), i)?
+        }
+        i => i,
+    })
+}
+
+fn to_call<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    fn_declarations: &mut FxHashMap<
+        Cow<'input, str>,
+        (
+            Vec<ast::Variable<SpirvWord>>,
+            SpirvWord,
+            Vec<ast::Variable<SpirvWord>>,
+        ),
+    >,
+    name: Cow<'input, str>,
+    i: ast::Instruction<SpirvWord>,
+) -> Result<ptx_parser::Instruction<SpirvWord>, TranslateError> {
+    let mut data_return = Vec::new();
+    let mut data_input = Vec::new();
+    let mut arguments_return = Vec::new();
+    let mut arguments_input = Vec::new();
+    ast::visit(&i, &mut |name: &SpirvWord,
+                         type_space: Option<(
+        &ptx_parser::Type,
+        ptx_parser::StateSpace,
+    )>,
+                         is_dst: bool,
+                         _: bool| {
+        let (type_, space) = type_space.ok_or_else(error_mismatched_type)?;
+        if is_dst {
+            data_return.push((type_.clone(), space));
+            arguments_return.push(*name);
+        } else {
+            data_input.push((type_.clone(), space));
+            arguments_input.push(*name);
+        };
+        Ok::<_, TranslateError>(())
+    })?;
+    let fn_name = match fn_declarations.entry(name) {
+        hash_map::Entry::Occupied(occupied_entry) => occupied_entry.get().1,
+        hash_map::Entry::Vacant(vacant_entry) => {
+            let name = vacant_entry.key().clone();
+            let full_name = [ZLUDA_PTX_PREFIX, &*name].concat();
+            let name = resolver.register_named(Cow::Owned(full_name.clone()), None);
+            vacant_entry.insert((
+                to_variables(resolver, &data_return),
+                name,
+                to_variables(resolver, &data_input),
+            ));
+            name
+        }
+    };
+    Ok(ast::Instruction::Call {
+        data: ptx_parser::CallDetails {
+            uniform: false,
+            return_arguments: data_return,
+            input_arguments: data_input,
+        },
+        arguments: ptx_parser::CallArgs {
+            return_arguments: arguments_return,
+            func: fn_name,
+            input_arguments: arguments_input,
+        },
+    })
+}
+
+fn to_variables<'input>(
+    resolver: &mut GlobalStringIdentResolver2<'input>,
+    arguments: &Vec<(ptx_parser::Type, ptx_parser::StateSpace)>,
+) -> Vec<ptx_parser::Variable<SpirvWord>> {
+    arguments
+        .iter()
+        .map(|(type_, space)| ast::Variable {
+            align: None,
+            v_type: type_.clone(),
+            state_space: *space,
+            name: resolver.register_unnamed(Some((type_.clone(), *space))),
+            array_init: Vec::new(),
+        })
+        .collect::<Vec<_>>()
+}
diff --git a/ptx_parser/src/ast.rs b/ptx_parser/src/ast.rs
index 65c624e..f0d3fbe 100644
--- a/ptx_parser/src/ast.rs
+++ b/ptx_parser/src/ast.rs
@@ -4,7 +4,7 @@ use super::{
 };
 use crate::{PtxError, PtxParserState};
 use bitflags::bitflags;
-use std::{cmp::Ordering, num::NonZeroU8};
+use std::{alloc::Layout, cmp::Ordering, num::NonZeroU8};
 
 pub enum Statement<P: Operand> {
     Label(P::Ident),
@@ -806,6 +806,32 @@ impl Type {
             None => Self::maybe_vector_parsed(prefix, scalar),
         }
     }
+
+    pub fn layout(&self) -> Layout {
+        match self {
+            Type::Scalar(type_) => type_.layout(),
+            Type::Vector(elements, scalar_type) => {
+                let scalar_layout = scalar_type.layout();
+                unsafe {
+                    Layout::from_size_align_unchecked(
+                        scalar_layout.size() * *elements as usize,
+                        scalar_layout.align() * *elements as usize,
+                    )
+                }
+            }
+            Type::Array(non_zero, scalar, vec) => {
+                let element_layout = Type::maybe_vector_parsed(*non_zero, *scalar).layout();
+                let len = vec.iter().copied().reduce(std::ops::Mul::mul).unwrap_or(0);
+                unsafe {
+                    Layout::from_size_align_unchecked(
+                        element_layout.size() * (len as usize),
+                        element_layout.align(),
+                    )
+                }
+            }
+            Type::Pointer(..) => Layout::new::<usize>(),
+        }
+    }
 }
 
 impl ScalarType {
@@ -831,6 +857,31 @@ impl ScalarType {
         }
     }
 
+    pub fn layout(self) -> Layout {
+        match self {
+            ScalarType::U8 | ScalarType::S8 | ScalarType::B8 => Layout::new::<u8>(),
+            ScalarType::U16
+            | ScalarType::S16
+            | ScalarType::B16
+            | ScalarType::F16
+            | ScalarType::BF16 => Layout::new::<u16>(),
+            ScalarType::U32
+            | ScalarType::S32
+            | ScalarType::B32
+            | ScalarType::F32
+            | ScalarType::U16x2
+            | ScalarType::S16x2
+            | ScalarType::F16x2
+            | ScalarType::BF16x2 => Layout::new::<u32>(),
+            ScalarType::U64 | ScalarType::S64 | ScalarType::B64 | ScalarType::F64 => {
+                Layout::new::<u64>()
+            }
+            ScalarType::B128 => unsafe { Layout::from_size_align_unchecked(16, 16) },
+            // Close enough
+            ScalarType::Pred => Layout::new::<u8>(),
+        }
+    }
+
     pub fn kind(self) -> ScalarKind {
         match self {
             ScalarType::U8 => ScalarKind::Unsigned,