diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_1_case.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_1_case.hir
index f2d45ac2d..69c0eb58b 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_1_case.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_1_case.hir
@@ -1,13 +1,13 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     default {
-    ^block2:
+    ^block3:
         v4 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v4;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_2_cases.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_2_cases.hir
index e08c6b981..679fa22ef 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_2_cases.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_2_cases.hir
@@ -1,18 +1,18 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     case 1 {
-    ^block2:
+    ^block3:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     }
     default {
-    ^block3:
+    ^block4:
         v5 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v5;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_3_cases.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_3_cases.hir
index 3d43af5b5..d4a214516 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_3_cases.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_3_cases.hir
@@ -1,23 +1,23 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     case 1 {
-    ^block2:
+    ^block3:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     }
     case 2 {
-    ^block3:
+    ^block4:
         v5 = arith.constant 2 : u32;
         scf.yield v5;
     }
     default {
-    ^block4:
+    ^block5:
         v6 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v6;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_4_cases.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_4_cases.hir
index 3dc46fe2c..0e5fed5ea 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_4_cases.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_4_cases.hir
@@ -1,28 +1,28 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     case 1 {
-    ^block2:
+    ^block3:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     }
     case 2 {
-    ^block3:
+    ^block4:
         v5 = arith.constant 2 : u32;
         scf.yield v5;
     }
     case 3 {
-    ^block4:
+    ^block5:
         v6 = arith.constant 3 : u32;
         scf.yield v6;
     }
     default {
-    ^block5:
+    ^block6:
         v7 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v7;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_5_cases.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_5_cases.hir
index 17a279636..014e7b023 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_5_cases.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_5_cases.hir
@@ -1,33 +1,33 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     case 1 {
-    ^block2:
+    ^block3:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     }
     case 2 {
-    ^block3:
+    ^block4:
         v5 = arith.constant 2 : u32;
         scf.yield v5;
     }
     case 3 {
-    ^block4:
+    ^block5:
         v6 = arith.constant 3 : u32;
         scf.yield v6;
     }
     case 4 {
-    ^block5:
+    ^block6:
         v7 = arith.constant 4 : u32;
         scf.yield v7;
     }
     default {
-    ^block6:
+    ^block7:
         v8 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v8;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_binary_search_7_cases.hir b/codegen/masm/src/lower/expected/utils_emit_binary_search_7_cases.hir
index a671639e2..9396b6f00 100644
--- a/codegen/masm/src/lower/expected/utils_emit_binary_search_7_cases.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_binary_search_7_cases.hir
@@ -1,43 +1,43 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = scf.index_switch v0 : u32 
     case 0 {
-    ^block1:
+    ^block2:
         v3 = arith.constant 0 : u32;
         scf.yield v3;
     }
     case 1 {
-    ^block2:
+    ^block3:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     }
     case 2 {
-    ^block3:
+    ^block4:
         v5 = arith.constant 2 : u32;
         scf.yield v5;
     }
     case 3 {
-    ^block4:
+    ^block5:
         v6 = arith.constant 3 : u32;
         scf.yield v6;
     }
     case 4 {
-    ^block5:
+    ^block6:
         v7 = arith.constant 4 : u32;
         scf.yield v7;
     }
     case 5 {
-    ^block6:
+    ^block7:
         v8 = arith.constant 5 : u32;
         scf.yield v8;
     }
     case 6 {
-    ^block7:
+    ^block8:
         v9 = arith.constant 6 : u32;
         scf.yield v9;
     }
     default {
-    ^block8:
+    ^block9:
         v10 = arith.mul v0, v1 : u32 #[overflow = checked];
         scf.yield v10;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_if.hir b/codegen/masm/src/lower/expected/utils_emit_if.hir
index bf547b88f..19b72f4a2 100644
--- a/codegen/masm/src/lower/expected/utils_emit_if.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_if.hir
@@ -1,13 +1,13 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = arith.constant 0 : u32;
     v3 = arith.eq v0, v1 : i1;
     v4 = scf.if v3 : u32 {
-    ^block1:
+    ^block2:
         v5 = arith.constant 1 : u32;
         scf.yield v5;
     } else {
-    ^block2:
+    ^block3:
         v6 = arith.mul v0, v2 : u32 #[overflow = checked];
         scf.yield v6;
     };
diff --git a/codegen/masm/src/lower/expected/utils_emit_if_nested.hir b/codegen/masm/src/lower/expected/utils_emit_if_nested.hir
index 12b4722bf..2ae841239 100644
--- a/codegen/masm/src/lower/expected/utils_emit_if_nested.hir
+++ b/codegen/masm/src/lower/expected/utils_emit_if_nested.hir
@@ -1,19 +1,19 @@
 public builtin.function @test(v0: u32, v1: u32) -> u32 {
-^block0(v0: u32, v1: u32):
+^block1(v0: u32, v1: u32):
     v2 = arith.eq v0, v1 : i1;
     v3 = scf.if v2 : u32 {
-    ^block1:
+    ^block2:
         v4 = arith.constant 1 : u32;
         scf.yield v4;
     } else {
-    ^block2:
+    ^block3:
         v5 = arith.lt v0, v1 : i1;
         v6 = scf.if v5 : u32 {
-        ^block3:
+        ^block4:
             v7 = arith.constant 2 : u32;
             scf.yield v7;
         } else {
-        ^block4:
+        ^block5:
             v8 = arith.mul v0, v1 : u32 #[overflow = checked];
             scf.yield v8;
         };
diff --git a/codegen/masm/src/lower/utils.rs b/codegen/masm/src/lower/utils.rs
index 6cd932b4c..aecf54579 100644
--- a/codegen/masm/src/lower/utils.rs
+++ b/codegen/masm/src/lower/utils.rs
@@ -493,11 +493,11 @@ mod tests {
     use midenc_dialect_scf::StructuredControlFlowOpBuilder;
     use midenc_expect_test::expect_file;
     use midenc_hir::{
-        dialects::builtin::{self, BuiltinOpBuilder, FunctionBuilder, FunctionRef},
+        dialects::builtin::{self, BuiltinOpBuilder, FunctionBuilder, FunctionRef, WorldBuilder},
         formatter::PrettyPrint,
         pass::AnalysisManager,
         version::Version,
-        AbiParam, Context, Ident, OpBuilder, Signature, Type,
+        AbiParam, BuilderExt, Context, Ident, OpBuilder, Signature, SymbolTable, Type,
     };
     use midenc_hir_analysis::analyses::LivenessAnalysis;
 
@@ -511,12 +511,18 @@ mod tests {
 
         let mut builder = OpBuilder::new(context.clone());
 
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function_ref = builder.create_function(
             Ident::with_empty_span("test".into()),
             Signature::new(
                 [AbiParam::new(Type::U32), AbiParam::new(Type::U32)],
                 [AbiParam::new(Type::U32)],
             ),
+            world,
         )?;
 
         let (a, b) = {
@@ -597,12 +603,18 @@ mod tests {
 
         let mut builder = OpBuilder::new(context.clone());
 
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function_ref = builder.create_function(
             Ident::with_empty_span("test".into()),
             Signature::new(
                 [AbiParam::new(Type::U32), AbiParam::new(Type::U32)],
                 [AbiParam::new(Type::U32)],
             ),
+            world,
         )?;
 
         let (a, b) = {
@@ -826,12 +838,18 @@ mod tests {
     ) -> Result<(FunctionRef, masm::Block), Report> {
         let mut builder = OpBuilder::new(context.clone());
 
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function_ref = builder.create_function(
             Ident::with_empty_span("test".into()),
             Signature::new(
                 [AbiParam::new(Type::U32), AbiParam::new(Type::U32)],
                 [AbiParam::new(Type::U32)],
             ),
+            world,
         )?;
 
         let (a, b) = {
diff --git a/dialects/scf/src/transforms/cfg_to_scf.rs b/dialects/scf/src/transforms/cfg_to_scf.rs
index 014200089..51bc43cf3 100644
--- a/dialects/scf/src/transforms/cfg_to_scf.rs
+++ b/dialects/scf/src/transforms/cfg_to_scf.rs
@@ -373,7 +373,7 @@ mod tests {
     use midenc_expect_test::expect_file;
     use midenc_hir::{
         dialects::builtin, pass, AbiParam, BuilderExt, Context, Ident, OpBuilder, PointerType,
-        Report, Signature, SourceSpan, Type,
+        Report, Signature, SourceSpan, SymbolTable, Type,
     };
 
     use super::*;
@@ -384,11 +384,17 @@ mod tests {
         let mut builder = OpBuilder::new(context.clone());
 
         let span = SourceSpan::default();
+
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = builtin::WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<builtin::Function, (_, _)>(span);
+            let builder = builder.create::<builtin::Function, (_, _, _)>(span);
             let name = Ident::new("test".into(), span);
             let signature = Signature::new([AbiParam::new(Type::U32)], [AbiParam::new(Type::U32)]);
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body
@@ -446,10 +452,15 @@ mod tests {
 
         let context = Rc::new(Context::default());
         let mut builder = OpBuilder::new(context.clone());
-
         let span = SourceSpan::default();
+
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = builtin::WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<builtin::Function, (_, _)>(span);
+            let builder = builder.create::<builtin::Function, (_, _, _)>(span);
             let name = Ident::new("test".into(), span);
             let signature = Signature::new(
                 [
@@ -460,7 +471,7 @@ mod tests {
                 ],
                 [AbiParam::new(Type::U32)],
             );
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body
@@ -571,11 +582,17 @@ mod tests {
         let mut builder = OpBuilder::new(context.clone());
 
         let span = SourceSpan::default();
+
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = builtin::WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<builtin::Function, (_, _)>(span);
+            let builder = builder.create::<builtin::Function, (_, _, _)>(span);
             let name = Ident::new("test".into(), span);
             let signature = Signature::new([AbiParam::new(Type::U32)], [AbiParam::new(Type::U32)]);
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body
@@ -630,8 +647,14 @@ mod tests {
         let mut builder = OpBuilder::new(context.clone());
 
         let span = SourceSpan::default();
+
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = builtin::WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<builtin::Function, (_, _)>(span);
+            let builder = builder.create::<builtin::Function, (_, _, _)>(span);
             let name = Ident::new("test".into(), span);
             let signature = Signature::new(
                 [
@@ -641,7 +664,7 @@ mod tests {
                 ],
                 [AbiParam::new(Type::U32)],
             );
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body for the following pseudocode:
@@ -743,8 +766,14 @@ mod tests {
         let mut builder = OpBuilder::new(context.clone());
 
         let span = SourceSpan::default();
+
+        let world_ref = builder.create::<builtin::World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = builtin::WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<builtin::Function, (_, _)>(span);
+            let builder = builder.create::<builtin::Function, (_, _, _)>(span);
             let name = Ident::new("test".into(), span);
             let signature = Signature::new(
                 [
@@ -754,7 +783,7 @@ mod tests {
                 ],
                 [AbiParam::new(Type::U32)],
             );
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body for the following pseudocode:
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_after.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_after.hir
index aee2ec449..945ea7a66 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_after.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_after.hir
@@ -1,51 +1,51 @@
 public builtin.function @test(v0: u32, v1: u32, v2: u32, v3: u32) -> u32 {
-^block0(v0: u32, v1: u32, v2: u32, v3: u32):
+^block1(v0: u32, v1: u32, v2: u32, v3: u32):
     v18 = arith.constant 1 : u32;
     v17 = ub.poison u32 : u32;
     v13 = arith.constant 0 : u32;
     v5 = arith.constant 0 : u32;
     v6 = arith.neq v1, v5 : i1;
     v22, v23, v24 = scf.if v6 : u32, u32, u32 {
-    ^block2:
+    ^block3:
         v9 = arith.incr v0 : u32;
         scf.yield v9, v17, v13;
     } else {
-    ^block3:
+    ^block4:
         v10 = arith.neq v3, v5 : i1;
         v33, v34, v35 = scf.if v10 : u32, u32, u32 {
-        ^block4:
+        ^block5:
             v11 = arith.incr v3 : u32;
             scf.yield v11, v17, v13;
         } else {
-        ^block5:
+        ^block6:
             scf.yield v17, v2, v18;
         };
         scf.yield v33, v34, v35;
     };
     v29, v30 = scf.index_switch v24 : u32, u32 
     case 0 {
-    ^block1:
+    ^block2:
         v7 = arith.eq v22, v5 : i1;
         v8 = arith.neq v7, v5 : i1;
         v31, v32 = scf.if v8 : u32, u32 {
-        ^block6:
+        ^block7:
             scf.yield v17, v18;
         } else {
-        ^block7:
+        ^block8:
             scf.yield v22, v13;
         };
         scf.yield v31, v32;
     }
     default {
-    ^block13:
+    ^block14:
         scf.yield v23, v13;
     };
     cf.switch v30 {
-        case 0 => ^block8(v29)
-        default => ^block9
+        case 0 => ^block9(v29)
+        default => ^block10
     };
-^block8(v12: u32):
+^block9(v12: u32):
     builtin.ret v12;
-^block9:
+^block10:
     ub.unreachable ;
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_before.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_before.hir
index 446f88e2e..b4dbe170e 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_before.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_conditional_early_exit_before.hir
@@ -1,25 +1,25 @@
 public builtin.function @test(v0: u32, v1: u32, v2: u32, v3: u32) -> u32 {
-^block0(v0: u32, v1: u32, v2: u32, v3: u32):
+^block1(v0: u32, v1: u32, v2: u32, v3: u32):
     v5 = arith.constant 0 : u32;
     v6 = arith.neq v1, v5 : i1;
-    cf.cond_br v6 ^block2, ^block3;
-^block1(v4: u32):
+    cf.cond_br v6 ^block3, ^block4;
+^block2(v4: u32):
     v7 = arith.eq v4, v5 : i1;
     v8 = arith.neq v7, v5 : i1;
-    cf.cond_br v8 ^block6, ^block7;
-^block2:
-    v9 = arith.incr v0 : u32;
-    cf.br ^block1(v9);
+    cf.cond_br v8 ^block7, ^block8;
 ^block3:
-    v10 = arith.neq v3, v5 : i1;
-    cf.cond_br v10 ^block4, ^block5;
+    v9 = arith.incr v0 : u32;
+    cf.br ^block2(v9);
 ^block4:
-    v11 = arith.incr v3 : u32;
-    cf.br ^block1(v11);
+    v10 = arith.neq v3, v5 : i1;
+    cf.cond_br v10 ^block5, ^block6;
 ^block5:
-    builtin.ret v2;
+    v11 = arith.incr v3 : u32;
+    cf.br ^block2(v11);
 ^block6:
-    ub.unreachable ;
+    builtin.ret v2;
 ^block7:
+    ub.unreachable ;
+^block8:
     builtin.ret v4;
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_after.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_after.hir
index 3ed535312..7ce0a98a4 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_after.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_after.hir
@@ -1,20 +1,20 @@
 public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
-^block0(v0: ptr<byte, u32>, v1: u32, v2: u32):
+^block1(v0: ptr<byte, u32>, v1: u32, v2: u32):
     v28 = arith.constant 2 : u32;
     v27 = ub.poison u32 : u32;
     v26 = arith.constant 1 : u32;
     v21 = arith.constant 0 : u32;
     v39, v40, v41, v42 = scf.while v21, v21, v27, v27 : u32, u32, u32, u32 {
-    ^block1(v3: u32, v4: u32, v32: u32, v34: u32):
+    ^block2(v3: u32, v4: u32, v32: u32, v34: u32):
         v8 = arith.lt v3, v1 : i1;
         v111, v112, v113, v114 = scf.if v8 : u32, u32, u32, u32 {
-        ^block3:
+        ^block4:
             v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
             v82, v83, v84, v85, v86, v87, v88, v89 = scf.while v21, v4, v27, v27, v27, v27, v27, v27 : u32, u32, u32, u32, u32, u32, u32, u32 {
-            ^block2(v5: u32, v6: u32, v63: u32, v65: u32, v67: u32, v69: u32, v71: u32, v73: u32):
+            ^block3(v5: u32, v6: u32, v63: u32, v65: u32, v67: u32, v69: u32, v71: u32, v73: u32):
                 v10 = arith.lt v5, v2 : i1;
                 v127, v128, v129, v130, v131, v132, v133, v134 = scf.if v10 : u32, u32, u32, u32, u32, u32, u32, u32 {
-                ^block5:
+                ^block6:
                     v12 = arith.add v9, v5 : u32 #[overflow = unchecked];
                     v13 = builtin.unrealized_conversion_cast v0 : u32;
                     v14 = arith.add v13, v12 : u32 #[overflow = unchecked];
@@ -23,48 +23,48 @@ public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
                     v17 = arith.incr v5 : u32;
                     v18, v19 = arith.add_overflowing v6, v16 : i1, u32;
                     v135, v136, v137, v138, v139, v140, v141, v142 = scf.if v18 : u32, u32, u32, u32, u32, u32, u32, u32 {
-                    ^block25:
+                    ^block26:
                         scf.yield v27, v27, v27, v27, v26, v21, v26, v21;
                     } else {
-                    ^block26:
+                    ^block27:
                         scf.yield v17, v19, v27, v27, v27, v27, v21, v26;
                     };
                     scf.yield v135, v136, v137, v138, v139, v140, v141, v142;
                 } else {
-                ^block24:
+                ^block25:
                     scf.yield v27, v27, v27, v27, v27, v27, v28, v21;
                 };
                 v106 = arith.trunc v134 : i1;
                 scf.condition v106, v127, v128, v6, v129, v130, v131, v132, v133;
             } do {
-            ^block19(v98: u32, v99: u32, v100: u32, v101: u32, v102: u32, v103: u32, v104: u32, v105: u32):
+            ^block20(v98: u32, v99: u32, v100: u32, v101: u32, v102: u32, v103: u32, v104: u32, v105: u32):
                 scf.yield v98, v99, v100, v101, v102, v103, v104, v105;
             };
             v115, v116, v117, v118 = scf.index_switch v89 : u32, u32, u32, u32 
             case 1 {
-            ^block22:
+            ^block23:
                 scf.yield v85, v86, v87, v88;
             }
             default {
-            ^block6:
+            ^block7:
                 v11 = arith.incr v3 : u32;
                 scf.yield v11, v84, v21, v26;
             };
             scf.yield v115, v116, v117, v118;
         } else {
-        ^block21:
+        ^block22:
             scf.yield v27, v27, v28, v21;
         };
         v51 = arith.trunc v114 : i1;
         scf.condition v51, v111, v112, v4, v113;
     } do {
-    ^block14(v47: u32, v48: u32, v49: u32, v50: u32):
+    ^block15(v47: u32, v48: u32, v49: u32, v50: u32):
         scf.yield v47, v48, v49, v50;
     };
     v144 = arith.eq v42, v26 : i1;
-    cf.cond_br v144 ^block7, ^block4;
-^block4:
+    cf.cond_br v144 ^block8, ^block5;
+^block5:
     builtin.ret v41;
-^block7:
+^block8:
     builtin.ret_imm 4294967295;
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_before.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_before.hir
index 7e4ed12b2..8b7445f3d 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_before.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_multiple_exit_nested_while_loop_before.hir
@@ -1,19 +1,19 @@
 public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
-^block0(v0: ptr<byte, u32>, v1: u32, v2: u32):
+^block1(v0: ptr<byte, u32>, v1: u32, v2: u32):
     v7 = arith.constant 0 : u32;
-    cf.br ^block1(v7, v7);
-^block1(v3: u32, v4: u32):
+    cf.br ^block2(v7, v7);
+^block2(v3: u32, v4: u32):
     v8 = arith.lt v3, v1 : i1;
-    cf.cond_br v8 ^block3(v4), ^block4;
-^block2(v5: u32, v6: u32):
+    cf.cond_br v8 ^block4(v4), ^block5;
+^block3(v5: u32, v6: u32):
     v10 = arith.lt v5, v2 : i1;
-    cf.cond_br v10 ^block5(v6), ^block6;
-^block3:
-    v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
-    cf.br ^block2(v7, v4);
+    cf.cond_br v10 ^block6(v6), ^block7;
 ^block4:
-    builtin.ret v4;
+    v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
+    cf.br ^block3(v7, v4);
 ^block5:
+    builtin.ret v4;
+^block6:
     v12 = arith.add v9, v5 : u32 #[overflow = unchecked];
     v13 = builtin.unrealized_conversion_cast v0 : u32;
     v14 = arith.add v13, v12 : u32 #[overflow = unchecked];
@@ -21,10 +21,10 @@ public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
     v16 = builtin.unrealized_conversion_cast v15 : u32;
     v17 = arith.incr v5 : u32;
     v18, v19 = arith.add_overflowing v6, v16 : i1, u32;
-    cf.cond_br v18 ^block7, ^block2(v17, v19);
-^block6:
-    v11 = arith.incr v3 : u32;
-    cf.br ^block1(v11, v6);
+    cf.cond_br v18 ^block8, ^block3(v17, v19);
 ^block7:
+    v11 = arith.incr v3 : u32;
+    cf.br ^block2(v11, v6);
+^block8:
     builtin.ret_imm 4294967295;
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_after.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_after.hir
index cfce15343..b69cf3656 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_after.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_after.hir
@@ -1,26 +1,26 @@
 public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
-^block0(v0: ptr<byte, u32>, v1: u32, v2: u32):
+^block1(v0: ptr<byte, u32>, v1: u32, v2: u32):
     v26 = ub.poison u32 : u32;
     v25 = arith.constant 1 : u32;
     v20 = arith.constant 0 : u32;
     v7 = arith.constant 0 : u32;
     v34, v35, v36 = scf.while v7, v7, v26 : u32, u32, u32 {
-    ^block1(v3: u32, v4: u32, v30: u32):
+    ^block2(v3: u32, v4: u32, v30: u32):
         v8 = arith.lt v3, v1 : i1;
         v65, v66, v67, v68 = scf.if v8 : u32, u32, u32, u32 {
-        ^block18:
+        ^block19:
             scf.yield v26, v26, v25, v20;
         } else {
-        ^block3:
+        ^block4:
             v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
             v55, v56, v57 = scf.while v7, v4, v26 : u32, u32, u32 {
-            ^block2(v5: u32, v6: u32, v51: u32):
+            ^block3(v5: u32, v6: u32, v51: u32):
                 v10 = arith.lt v5, v2 : i1;
                 v69, v70, v71, v72 = scf.if v10 : u32, u32, u32, u32 {
-                ^block19:
+                ^block20:
                     scf.yield v26, v26, v25, v20;
                 } else {
-                ^block5:
+                ^block6:
                     v12 = arith.add v9, v5 : u32 #[overflow = unchecked];
                     v13 = builtin.unrealized_conversion_cast v0 : u32;
                     v14 = arith.add v13, v12 : u32 #[overflow = unchecked];
@@ -33,7 +33,7 @@ public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
                 v64 = arith.trunc v72 : i1;
                 scf.condition v64, v69, v70, v6;
             } do {
-            ^block17(v61: u32, v62: u32, v63: u32):
+            ^block18(v61: u32, v62: u32, v63: u32):
                 scf.yield v61, v62, v63;
             };
             v11 = arith.incr v3 : u32;
@@ -42,7 +42,7 @@ public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
         v43 = arith.trunc v68 : i1;
         scf.condition v43, v65, v66, v4;
     } do {
-    ^block12(v40: u32, v41: u32, v42: u32):
+    ^block13(v40: u32, v41: u32, v42: u32):
         scf.yield v40, v41, v42;
     };
     builtin.ret v36;
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_before.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_before.hir
index 5f5e41efa..fa746727f 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_before.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_nested_while_loop_before.hir
@@ -1,19 +1,19 @@
 public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
-^block0(v0: ptr<byte, u32>, v1: u32, v2: u32):
+^block1(v0: ptr<byte, u32>, v1: u32, v2: u32):
     v7 = arith.constant 0 : u32;
-    cf.br ^block1(v7, v7);
-^block1(v3: u32, v4: u32):
+    cf.br ^block2(v7, v7);
+^block2(v3: u32, v4: u32):
     v8 = arith.lt v3, v1 : i1;
-    cf.cond_br v8 ^block4, ^block3(v4);
-^block2(v5: u32, v6: u32):
+    cf.cond_br v8 ^block5, ^block4(v4);
+^block3(v5: u32, v6: u32):
     v10 = arith.lt v5, v2 : i1;
-    cf.cond_br v10 ^block6, ^block5(v6);
-^block3:
-    v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
-    cf.br ^block2(v7, v4);
+    cf.cond_br v10 ^block7, ^block6(v6);
 ^block4:
-    builtin.ret v4;
+    v9 = arith.mul v3, v2 : u32 #[overflow = unchecked];
+    cf.br ^block3(v7, v4);
 ^block5:
+    builtin.ret v4;
+^block6:
     v12 = arith.add v9, v5 : u32 #[overflow = unchecked];
     v13 = builtin.unrealized_conversion_cast v0 : u32;
     v14 = arith.add v13, v12 : u32 #[overflow = unchecked];
@@ -21,8 +21,8 @@ public builtin.function @test(v0: ptr<byte, u32>, v1: u32, v2: u32) -> u32 {
     v16 = builtin.unrealized_conversion_cast v15 : u32;
     v17 = arith.incr v5 : u32;
     v18 = arith.add v6, v16 : u32 #[overflow = unchecked];
-    cf.br ^block2(v17, v18);
-^block6:
+    cf.br ^block3(v17, v18);
+^block7:
     v11 = arith.incr v3 : u32;
-    cf.br ^block1(v11, v6);
+    cf.br ^block2(v11, v6);
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_after.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_after.hir
index 6ee59e782..f5aec2ce4 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_after.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_after.hir
@@ -1,13 +1,13 @@
 public builtin.function @test(v0: u32) -> u32 {
-^block0(v0: u32):
+^block1(v0: u32):
     v2 = arith.constant 0 : u32;
     v3 = arith.eq v0, v2 : i1;
     v8 = scf.if v3 : u32 {
-    ^block1:
+    ^block2:
         v4 = arith.incr v0 : u32;
         scf.yield v4;
     } else {
-    ^block2:
+    ^block3:
         v5 = arith.mul v0, v0 : u32 #[overflow = checked];
         scf.yield v5;
     };
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_before.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_before.hir
index 2ad7c035d..7c1114f89 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_before.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_conditional_before.hir
@@ -1,14 +1,14 @@
 public builtin.function @test(v0: u32) -> u32 {
-^block0(v0: u32):
+^block1(v0: u32):
     v2 = arith.constant 0 : u32;
     v3 = arith.eq v0, v2 : i1;
-    cf.cond_br v3 ^block1, ^block2;
-^block1:
-    v4 = arith.incr v0 : u32;
-    cf.br ^block3(v4);
+    cf.cond_br v3 ^block2, ^block3;
 ^block2:
+    v4 = arith.incr v0 : u32;
+    cf.br ^block4(v4);
+^block3:
     v5 = arith.mul v0, v0 : u32 #[overflow = checked];
-    cf.br ^block3(v5);
-^block3(v1: u32):
+    cf.br ^block4(v5);
+^block4(v1: u32):
     builtin.ret v1;
 };
\ No newline at end of file
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_after.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_after.hir
index ce156c761..799767b8a 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_after.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_after.hir
@@ -1,18 +1,18 @@
 public builtin.function @test(v0: u32) -> u32 {
-^block0(v0: u32):
+^block1(v0: u32):
     v15 = ub.poison u32 : u32;
     v14 = arith.constant 1 : u32;
     v9 = arith.constant 0 : u32;
     v3 = arith.constant 0 : u32;
     v4 = arith.constant 1 : u32;
     v23, v24, v25 = scf.while v0, v3, v15 : u32, u32, u32 {
-    ^block1(v1: u32, v2: u32, v19: u32):
+    ^block2(v1: u32, v2: u32, v19: u32):
         v5 = arith.eq v1, v3 : i1;
         v33, v34, v35, v36 = scf.if v5 : u32, u32, u32, u32 {
-        ^block10:
+        ^block11:
             scf.yield v15, v15, v14, v9;
         } else {
-        ^block3:
+        ^block4:
             v6 = arith.sub v1, v4 : u32 #[overflow = unchecked];
             v7 = arith.incr v2 : u32;
             scf.yield v6, v7, v9, v14;
@@ -20,7 +20,7 @@ public builtin.function @test(v0: u32) -> u32 {
         v32 = arith.trunc v36 : i1;
         scf.condition v32, v33, v34, v2;
     } do {
-    ^block9(v29: u32, v30: u32, v31: u32):
+    ^block10(v29: u32, v30: u32, v31: u32):
         scf.yield v29, v30, v31;
     };
     builtin.ret v25;
diff --git a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_before.hir b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_before.hir
index c744417e2..031c7cb9f 100644
--- a/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_before.hir
+++ b/dialects/scf/src/transforms/expected/cfg_to_scf_lift_simple_while_loop_before.hir
@@ -1,15 +1,15 @@
 public builtin.function @test(v0: u32) -> u32 {
-^block0(v0: u32):
+^block1(v0: u32):
     v3 = arith.constant 0 : u32;
     v4 = arith.constant 1 : u32;
-    cf.br ^block1(v0, v3);
-^block1(v1: u32, v2: u32):
+    cf.br ^block2(v0, v3);
+^block2(v1: u32, v2: u32):
     v5 = arith.eq v1, v3 : i1;
-    cf.cond_br v5 ^block2, ^block3;
-^block2:
-    builtin.ret v2;
+    cf.cond_br v5 ^block3, ^block4;
 ^block3:
+    builtin.ret v2;
+^block4:
     v6 = arith.sub v1, v4 : u32 #[overflow = unchecked];
     v7 = arith.incr v2 : u32;
-    cf.br ^block1(v6, v7);
+    cf.br ^block2(v6, v7);
 };
\ No newline at end of file
diff --git a/eval/src/tests.rs b/eval/src/tests.rs
index 845e380fd..640505997 100644
--- a/eval/src/tests.rs
+++ b/eval/src/tests.rs
@@ -5,8 +5,8 @@ use midenc_dialect_cf::ControlFlowOpBuilder;
 use midenc_dialect_hir::HirOpBuilder;
 use midenc_dialect_scf::StructuredControlFlowOpBuilder;
 use midenc_hir::{
-    dialects::builtin::{BuiltinOpBuilder, FunctionBuilder},
-    AbiParam, Builder, Context, Ident, Op, OpBuilder, ProgramPoint, Report, Signature, SourceSpan,
+    dialects::builtin::{BuiltinOpBuilder, FunctionBuilder, World, WorldBuilder},
+    AbiParam, Builder, BuilderExt, Context, Ident, Op, OpBuilder, Report, Signature, SourceSpan,
     SymbolTable, Type, ValueRef,
 };
 
@@ -72,9 +72,15 @@ fn eval_callable_test() -> Result<(), Report> {
 
     let mut builder = OpBuilder::new(test_context.context.clone());
 
+    let world_ref = builder.create::<World, ()>(Default::default())()
+        .expect("Error unrelated to test: Failed to build world.");
+    let mut world_builder = WorldBuilder::new(world_ref);
+    let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
     let function = builder.create_function(
         Ident::with_empty_span("test".into()),
         Signature::new([AbiParam::new(Type::I1)], [AbiParam::new(Type::U32)]),
+        world,
     )?;
 
     {
@@ -119,29 +125,32 @@ fn call_handling_test() -> Result<(), Report> {
 
     let mut builder = OpBuilder::new(test_context.context.clone());
 
-    let mut module = builder.create_module(Ident::with_empty_span("test".into()))?;
+    let world_ref = builder.create::<World, ()>(Default::default())()
+        .expect("Error unrelated to test: Failed to build world.");
+    let mut world_builder = WorldBuilder::new(world_ref);
+    let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
+    let mut module = builder.create_module(Ident::with_empty_span("test".into()), world)?;
 
     let module_body = module.borrow().body().as_region_ref();
     builder.create_block(module_body, None, &[]);
 
+    let module_ref = &mut module.borrow_mut().as_symbol_table_ref();
+
     // Define entry
     let entry = builder.create_function(
         Ident::with_empty_span("entrypoint".into()),
         Signature::new([AbiParam::new(Type::I1)], [AbiParam::new(Type::U32)]),
+        module_ref,
     )?;
-    module
-        .borrow_mut()
-        .symbol_manager_mut()
-        .insert_new(entry, ProgramPoint::Invalid);
 
     // Define callee
     let callee_signature = Signature::new([AbiParam::new(Type::I1)], [AbiParam::new(Type::I1)]);
-    let callee = builder
-        .create_function(Ident::with_empty_span("callee".into()), callee_signature.clone())?;
-    module
-        .borrow_mut()
-        .symbol_manager_mut()
-        .insert_new(callee, ProgramPoint::Invalid);
+    let callee = builder.create_function(
+        Ident::with_empty_span("callee".into()),
+        callee_signature.clone(),
+        module_ref,
+    )?;
 
     {
         let mut builder = FunctionBuilder::new(entry, &mut builder);
diff --git a/hir-macros/src/operation.rs b/hir-macros/src/operation.rs
index 3f7928a1d..448d1b039 100644
--- a/hir-macros/src/operation.rs
+++ b/hir-macros/src/operation.rs
@@ -11,6 +11,8 @@ use syn::{parse_quote, spanned::Spanned, Ident, Token};
 pub fn derive_operation(input: syn::DeriveInput) -> darling::Result<proc_macro2::TokenStream> {
     let op = OpDefinition::from_derive_input(&input)?;
 
+    // This method is implicitly implemented using `to_tokens`, and acts as a
+    // convenience method for consumers of the `ToTokens` trait.
     Ok(op.into_token_stream())
 }
 
@@ -51,6 +53,11 @@ pub struct OpDefinition {
     /// Keyed successor groups are handled a bit differently than "normal" successor groups in terms
     /// of the types expected by the op builder for this type.
     successors: Vec<SuccessorGroup>,
+    /// Indicates whether the current operation could belong to a [`SymbolTable`].
+    ///
+    /// If true, this operation's builder will have an additional parameter of type
+    ///`parent_symbol_table: &mut SymbolTableRef`.
+    belongs_in_symbol_table: bool,
     /// The symbolic references held by this op
     symbols: Vec<Symbol>,
     /// The struct definition
@@ -123,6 +130,7 @@ impl OpDefinition {
             operands: vec![],
             results: None,
             successors: vec![],
+            belongs_in_symbol_table: false,
             symbols: vec![],
             op,
             op_builder_impl,
@@ -345,6 +353,35 @@ impl OpDefinition {
             }
         }
 
+        // If the operations has the "BelongsInSymbolTable" trait, then an additional parameter is
+        // added to the Operation::create and OpBuilder function of type:
+        // parent_symbol_table: &mut SymbolTableRef,
+        // This is a reference to the symbol table of the parent where this operation will be added.
+        if self
+            .traits
+            .iter()
+            .any(|tr| tr.get_ident().unwrap() == stringify!(BelongsInSymbolTable))
+        {
+            let parent_symbol_table =
+                Ident::new("parent_symbol_table", proc_macro2::Span::call_site());
+
+            let parent_symbol_type = syn::Type::Reference(syn::TypeReference {
+                and_token: syn::token::And(proc_macro2::Span::call_site()),
+                lifetime: None,
+                mutability: Some(syn::token::Mut(proc_macro2::Span::call_site())),
+                elem: Box::new(make_type(stringify!(SymbolTableRef))),
+            });
+
+            create_params.push(OpCreateParam {
+                param_ty: OpCreateParamType::BuildOnlyParameter(
+                    parent_symbol_table.clone(),
+                    parent_symbol_type,
+                ),
+                r#default: false,
+            });
+            self.belongs_in_symbol_table = true;
+        }
+
         self.op_builder_impl.set_create_params(&self.op.generics, create_params);
 
         Ok(())
@@ -566,7 +603,7 @@ impl quote::ToTokens for BuildOp<'_> {
         match self.0.results.as_ref() {
             None => {
                 tokens.extend(quote! {
-                    op_builder.build()
+                    let op = op_builder.build();
                 });
             }
             Some(group) => {
@@ -639,13 +676,43 @@ impl quote::ToTokens for BuildOp<'_> {
                         #verify_result_constraints
                     }
 
-                    Ok(op)
+                    // We save the operation in a variable in case it needs to be modified later on
+                    let op = Ok(op);
                 })
             }
         }
     }
 }
 
+struct ModifyOp<'a>(&'a OpDefinition);
+impl quote::ToTokens for ModifyOp<'_> {
+    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
+        if self.0.belongs_in_symbol_table {
+            tokens.extend(quote! {
+                op.as_ref().map(|op| {
+                    let is_new = parent_symbol_table.borrow_mut().symbol_manager_mut().insert_new(*op, crate::ProgramPoint::Invalid);
+                    assert!(
+                        is_new,
+                        "{} already exists in {}",
+                        op.borrow().name(),
+                        parent_symbol_table.borrow().as_symbol_table_operation().name()
+                    );
+                });
+            });
+        };
+    }
+}
+
+#[allow(dead_code)]
+struct ReturnOp<'a>(&'a OpDefinition);
+impl quote::ToTokens for ReturnOp<'_> {
+    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
+        tokens.extend(quote! {
+            op
+        });
+    }
+}
+
 impl quote::ToTokens for OpCreateFn<'_> {
     fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
         let dialect = &self.op.dialect;
@@ -670,6 +737,8 @@ impl quote::ToTokens for OpCreateFn<'_> {
         });
         let with_successors = WithSuccessors(self.op);
         let build_op = BuildOp(self.op);
+        let modify_op = ModifyOp(self.op);
+        let return_op = ReturnOp(self.op);
 
         tokens.extend(quote! {
             /// Manually construct a new [#op_ident]
@@ -719,8 +788,14 @@ impl quote::ToTokens for OpCreateFn<'_> {
                 #with_successors
                 #with_results
 
-                // Finalize construction of this op, verifying it
+                /// Construct the op, verifying it
                 #build_op
+
+                /// Apply modifications to the op
+                #modify_op
+
+                /// Return the op
+                #return_op
             }
         });
     }
@@ -2362,6 +2437,8 @@ pub enum OpCreateParamType {
     #[allow(dead_code)]
     OperandGroup(Ident, syn::Type),
     CustomField(Ident, syn::Type),
+    /// Parameters that are only used in the Operation::create and are not stored in the resulting Operation
+    BuildOnlyParameter(Ident, syn::Type),
     Successor(Ident),
     SuccessorGroupNamed(Ident),
     SuccessorGroupKeyed(Ident, syn::Type),
@@ -2375,6 +2452,7 @@ impl OpCreateParam {
             | OpCreateParamType::CustomField(name, _)
             | OpCreateParamType::Operand(Operand { name, .. })
             | OpCreateParamType::OperandGroup(name, _)
+            | OpCreateParamType::BuildOnlyParameter(name, _)
             | OpCreateParamType::SuccessorGroupNamed(name)
             | OpCreateParamType::SuccessorGroupKeyed(name, _)
             | OpCreateParamType::Symbol(Symbol { name, .. }) => vec![name.clone()],
@@ -2400,6 +2478,7 @@ impl OpCreateParam {
                 vec![ty.clone()]
             }
             OpCreateParamType::Operand(_) => vec![make_type("::midenc_hir::ValueRef")],
+            OpCreateParamType::BuildOnlyParameter(_, ty) => vec![ty.clone()],
             OpCreateParamType::OperandGroup(group_name, _)
             | OpCreateParamType::SuccessorGroupNamed(group_name)
             | OpCreateParamType::SuccessorGroupKeyed(group_name, _) => {
diff --git a/hir/src/dialects/builtin/builders.rs b/hir/src/dialects/builtin/builders.rs
index 5e0bbff28..2361ef00a 100644
--- a/hir/src/dialects/builtin/builders.rs
+++ b/hir/src/dialects/builtin/builders.rs
@@ -7,7 +7,7 @@ pub use self::{component::*, function::*, module::*, world::*};
 use super::ops::*;
 use crate::{
     constants::ConstantData, Builder, BuilderExt, Ident, Immediate, OpBuilder, Report, Signature,
-    SourceSpan, Spanned, Type, UnsafeIntrusiveEntityRef, ValueRef, Visibility,
+    SourceSpan, Spanned, SymbolTableRef, Type, UnsafeIntrusiveEntityRef, ValueRef, Visibility,
 };
 
 pub trait BuiltinOpBuilder<'f, B: ?Sized + Builder> {
@@ -16,18 +16,23 @@ pub trait BuiltinOpBuilder<'f, B: ?Sized + Builder> {
         op_builder(name)
     }
 
-    fn create_module(&mut self, name: Ident) -> Result<ModuleRef, Report> {
-        let op_builder = self.builder_mut().create::<Module, (_,)>(name.span());
-        op_builder(name)
+    fn create_module(
+        &mut self,
+        name: Ident,
+        parent_symbol_table: &mut SymbolTableRef,
+    ) -> Result<ModuleRef, Report> {
+        let op_builder = self.builder_mut().create::<Module, (_, _)>(name.span());
+        op_builder(name, parent_symbol_table)
     }
 
     fn create_function(
         &mut self,
         name: Ident,
         signature: Signature,
+        parent_symbol_table: &mut SymbolTableRef,
     ) -> Result<FunctionRef, Report> {
-        let op_builder = self.builder_mut().create::<Function, (_, _)>(name.span());
-        op_builder(name, signature)
+        let op_builder = self.builder_mut().create::<Function, (_, _, _)>(name.span());
+        op_builder(name, signature, parent_symbol_table)
     }
 
     fn create_global_variable(
@@ -35,9 +40,10 @@ pub trait BuiltinOpBuilder<'f, B: ?Sized + Builder> {
         name: Ident,
         visibility: Visibility,
         ty: Type,
+        parent_symbol_table: &mut SymbolTableRef,
     ) -> Result<GlobalVariableRef, Report> {
-        let op_builder = self.builder_mut().create::<GlobalVariable, (_, _, _)>(name.span());
-        op_builder(name, visibility, ty)
+        let op_builder = self.builder_mut().create::<GlobalVariable, (_, _, _, _)>(name.span());
+        op_builder(name, visibility, ty, parent_symbol_table)
     }
 
     fn create_data_segment(
diff --git a/hir/src/dialects/builtin/builders/component.rs b/hir/src/dialects/builtin/builders/component.rs
index f6273a0d0..5ed154fca 100644
--- a/hir/src/dialects/builtin/builders/component.rs
+++ b/hir/src/dialects/builtin/builders/component.rs
@@ -31,17 +31,9 @@ impl ComponentBuilder {
     }
 
     pub fn define_module(&mut self, name: Ident) -> Result<ModuleRef, Report> {
-        let module_ref = self.builder.create_module(name)?;
-        let is_new = self
-            .component
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(module_ref, crate::ProgramPoint::Invalid);
-        assert!(
-            is_new,
-            "module with the name {name} already exists in component {}",
-            self.component.borrow().name()
-        );
+        let symbol_table = &mut self.component.borrow_mut().as_symbol_table_ref();
+        let module_ref = self.builder.create_module(name, symbol_table)?;
+
         Ok(module_ref)
     }
 
@@ -66,13 +58,9 @@ impl ComponentBuilder {
         name: Ident,
         signature: Signature,
     ) -> Result<FunctionRef, Report> {
-        let function_ref = self.builder.create_function(name, signature)?;
-        let is_new = self
-            .component
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(function_ref, crate::ProgramPoint::Invalid);
-        assert!(is_new, "function with the name {name} already exists");
+        let symbol_table = &mut self.component.borrow_mut().as_symbol_table_ref();
+        let function_ref = self.builder.create_function(name, signature, symbol_table)?;
+
         Ok(function_ref)
     }
 }
diff --git a/hir/src/dialects/builtin/builders/module.rs b/hir/src/dialects/builtin/builders/module.rs
index f61fca08e..2ed37d2b0 100644
--- a/hir/src/dialects/builtin/builders/module.rs
+++ b/hir/src/dialects/builtin/builders/module.rs
@@ -51,13 +51,9 @@ impl ModuleBuilder {
         name: Ident,
         signature: Signature,
     ) -> Result<FunctionRef, Report> {
-        let function_ref = self.builder.create_function(name, signature)?;
-        let is_new = self
-            .module
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(function_ref, crate::ProgramPoint::Invalid);
-        assert!(is_new, "function with the name {name} already exists");
+        let symbol_table = &mut self.module.borrow_mut().as_symbol_table_ref();
+        let function_ref = self.builder.create_function(name, signature, symbol_table)?;
+
         Ok(function_ref)
     }
 
@@ -71,13 +67,10 @@ impl ModuleBuilder {
         visibility: Visibility,
         ty: Type,
     ) -> Result<UnsafeIntrusiveEntityRef<GlobalVariable>, Report> {
-        let global_var_ref = self.builder.create_global_variable(name, visibility, ty)?;
-        let is_new = self
-            .module
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(global_var_ref, crate::ProgramPoint::Invalid);
-        assert!(is_new, "global variable with the name {name} already exists");
+        let symbol_table = &mut self.module.borrow_mut().as_symbol_table_ref();
+        let global_var_ref =
+            self.builder.create_global_variable(name, visibility, ty, symbol_table)?;
+
         Ok(global_var_ref)
     }
 
@@ -118,13 +111,9 @@ impl ModuleBuilder {
     /// Declare a new nested module `name`
     pub fn declare_module(&mut self, name: Ident) -> Result<ModuleRef, Report> {
         let builder = PrimModuleBuilder::new(&mut self.builder, name.span());
-        let module_ref = builder(name)?;
-        let is_new = self
-            .module
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(module_ref, crate::ProgramPoint::Invalid);
-        assert!(is_new, "module with the name {name} already exists in world",);
+        let symbol_table = &mut self.module.borrow_mut().as_symbol_table_ref();
+        let module_ref = builder(name, symbol_table)?;
+
         Ok(module_ref)
     }
 
diff --git a/hir/src/dialects/builtin/builders/world.rs b/hir/src/dialects/builtin/builders/world.rs
index 38408b6b7..3f29632ed 100644
--- a/hir/src/dialects/builtin/builders/world.rs
+++ b/hir/src/dialects/builtin/builders/world.rs
@@ -42,21 +42,10 @@ impl WorldBuilder {
         ver: Version,
     ) -> Result<ComponentRef, Report> {
         let builder = PrimComponentBuilder::new(&mut self.builder, name.span());
-        let component_ref = builder(ns, name, ver.clone())?;
-        let is_new = self
-            .world
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(component_ref, crate::ProgramPoint::Invalid);
-        assert!(
-            is_new,
-            "component {} already exists in world",
-            ComponentId {
-                namespace: ns.name,
-                name: name.name,
-                version: ver
-            }
-        );
+        let symbol_table = &mut self.world.borrow_mut().as_symbol_table_ref();
+
+        let component_ref = builder(ns, name, ver.clone(), symbol_table)?;
+
         Ok(component_ref)
     }
 
@@ -72,13 +61,9 @@ impl WorldBuilder {
     /// Declare a new world-level module `name`
     pub fn declare_module(&mut self, name: Ident) -> Result<ModuleRef, Report> {
         let builder = PrimModuleBuilder::new(&mut self.builder, name.span());
-        let module_ref = builder(name)?;
-        let is_new = self
-            .world
-            .borrow_mut()
-            .symbol_manager_mut()
-            .insert_new(module_ref, crate::ProgramPoint::Invalid);
-        assert!(is_new, "module with the name {name} already exists in world",);
+        let symbol_table = &mut self.world.borrow_mut().as_symbol_table_ref();
+        let module_ref = builder(name, symbol_table)?;
+
         Ok(module_ref)
     }
 
diff --git a/hir/src/dialects/builtin/ops/component.rs b/hir/src/dialects/builtin/ops/component.rs
index 2f7d275d5..6ea6863e0 100644
--- a/hir/src/dialects/builtin/ops/component.rs
+++ b/hir/src/dialects/builtin/ops/component.rs
@@ -7,12 +7,12 @@ use crate::{
     derive::operation,
     dialects::builtin::BuiltinDialect,
     traits::{
-        GraphRegionNoTerminator, HasOnlyGraphRegion, IsolatedFromAbove, NoRegionArguments,
-        NoTerminator, SingleBlock, SingleRegion,
+        BelongsInSymbolTable, GraphRegionNoTerminator, HasOnlyGraphRegion, IsolatedFromAbove,
+        NoRegionArguments, NoTerminator, SingleBlock, SingleRegion,
     },
     version::Version,
     Ident, OpPrinter, Operation, RegionKind, RegionKindInterface, Symbol, SymbolManager,
-    SymbolManagerMut, SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolUseList,
+    SymbolManagerMut, SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolTableRef, SymbolUseList,
     UnsafeIntrusiveEntityRef, Usable, Visibility,
 };
 
@@ -69,6 +69,7 @@ pub type ComponentRef = UnsafeIntrusiveEntityRef<Component>;
         HasOnlyGraphRegion,
         GraphRegionNoTerminator,
         IsolatedFromAbove,
+        BelongsInSymbolTable,
     ),
     implements(RegionKindInterface, SymbolTable, Symbol, OpPrinter)
 )]
@@ -192,6 +193,11 @@ impl SymbolTable for Component {
         &self.op
     }
 
+    #[inline(always)]
+    fn as_symbol_table_ref(&self) -> SymbolTableRef {
+        unsafe { SymbolTableRef::from_raw(self) }
+    }
+
     #[inline(always)]
     fn as_symbol_table_operation_mut(&mut self) -> &mut Operation {
         &mut self.op
diff --git a/hir/src/dialects/builtin/ops/function.rs b/hir/src/dialects/builtin/ops/function.rs
index 95004f693..24c890fc2 100644
--- a/hir/src/dialects/builtin/ops/function.rs
+++ b/hir/src/dialects/builtin/ops/function.rs
@@ -6,11 +6,13 @@ use crate::{
     define_attr_type,
     derive::operation,
     dialects::builtin::BuiltinDialect,
-    traits::{AnyType, IsolatedFromAbove, ReturnLike, SingleRegion, Terminator},
+    traits::{
+        AnyType, BelongsInSymbolTable, IsolatedFromAbove, ReturnLike, SingleRegion, Terminator,
+    },
     AttrPrinter, BlockRef, CallableOpInterface, Context, Ident, Immediate, Op, OpPrinter,
     OpPrintingFlags, Operation, RegionKind, RegionKindInterface, RegionRef, Signature, Symbol,
-    SymbolName, SymbolUse, SymbolUseList, Type, UnsafeIntrusiveEntityRef, Usable, ValueRef,
-    Visibility,
+    SymbolName, SymbolTableRef, SymbolUse, SymbolUseList, Type, UnsafeIntrusiveEntityRef, Usable,
+    ValueRef, Visibility,
 };
 
 trait UsableSymbol = Usable<Use = SymbolUse>;
@@ -75,13 +77,13 @@ impl AttrPrinter for LocalVariable {
 
 #[operation(
     dialect = BuiltinDialect,
-    traits(SingleRegion, IsolatedFromAbove),
+    traits(SingleRegion, IsolatedFromAbove, BelongsInSymbolTable),
     implements(
         UsableSymbol,
         Symbol,
         CallableOpInterface,
         RegionKindInterface,
-        OpPrinter
+        OpPrinter,
     )
 )]
 pub struct Function {
diff --git a/hir/src/dialects/builtin/ops/global_variable.rs b/hir/src/dialects/builtin/ops/global_variable.rs
index c46c0cf10..f53e7c71a 100644
--- a/hir/src/dialects/builtin/ops/global_variable.rs
+++ b/hir/src/dialects/builtin/ops/global_variable.rs
@@ -8,12 +8,12 @@ use crate::{
         MemoryEffect, MemoryEffectOpInterface, Pure,
     },
     traits::{
-        InferTypeOpInterface, IsolatedFromAbove, NoRegionArguments, PointerOf, SingleBlock,
-        SingleRegion, UInt8,
+        BelongsInSymbolTable, InferTypeOpInterface, IsolatedFromAbove, NoRegionArguments,
+        PointerOf, SingleBlock, SingleRegion, UInt8,
     },
     AsSymbolRef, Context, Ident, Op, OpPrinter, Operation, PointerType, Report, Spanned, Symbol,
-    SymbolName, SymbolRef, SymbolUseList, Type, UnsafeIntrusiveEntityRef, Usable, Value,
-    Visibility,
+    SymbolName, SymbolRef, SymbolTableRef, SymbolUseList, Type, UnsafeIntrusiveEntityRef, Usable,
+    Value, Visibility,
 };
 
 pub type GlobalVariableRef = UnsafeIntrusiveEntityRef<GlobalVariable>;
@@ -34,6 +34,7 @@ pub type GlobalVariableRef = UnsafeIntrusiveEntityRef<GlobalVariable>;
         SingleBlock,
         NoRegionArguments,
         IsolatedFromAbove,
+        BelongsInSymbolTable,
     ),
     implements(Symbol, OpPrinter)
 )]
diff --git a/hir/src/dialects/builtin/ops/interface.rs b/hir/src/dialects/builtin/ops/interface.rs
index 856b18a99..14a486f5b 100644
--- a/hir/src/dialects/builtin/ops/interface.rs
+++ b/hir/src/dialects/builtin/ops/interface.rs
@@ -8,8 +8,8 @@ use crate::{
         NoTerminator, SingleBlock, SingleRegion,
     },
     Ident, Op, Operation, RegionKind, RegionKindInterface, Symbol, SymbolManager, SymbolManagerMut,
-    SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolUseList, UnsafeIntrusiveEntityRef, Usable,
-    Visibility,
+    SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolTableRef, SymbolUseList,
+    UnsafeIntrusiveEntityRef, Usable, Visibility,
 };
 
 pub type InterfaceRef = UnsafeIntrusiveEntityRef<Interface>;
@@ -119,6 +119,11 @@ impl SymbolTable for Interface {
         &self.op
     }
 
+    #[inline(always)]
+    fn as_symbol_table_ref(&self) -> SymbolTableRef {
+        unsafe { SymbolTableRef::from_raw(self) }
+    }
+
     #[inline(always)]
     fn as_symbol_table_operation_mut(&mut self) -> &mut Operation {
         &mut self.op
diff --git a/hir/src/dialects/builtin/ops/module.rs b/hir/src/dialects/builtin/ops/module.rs
index 5fb6100fc..3867d54c9 100644
--- a/hir/src/dialects/builtin/ops/module.rs
+++ b/hir/src/dialects/builtin/ops/module.rs
@@ -2,11 +2,11 @@ use crate::{
     derive::operation,
     dialects::builtin::BuiltinDialect,
     traits::{
-        GraphRegionNoTerminator, HasOnlyGraphRegion, IsolatedFromAbove, NoRegionArguments,
-        NoTerminator, SingleBlock, SingleRegion,
+        BelongsInSymbolTable, GraphRegionNoTerminator, HasOnlyGraphRegion, IsolatedFromAbove,
+        NoRegionArguments, NoTerminator, SingleBlock, SingleRegion,
     },
     Ident, OpPrinter, Operation, RegionKind, RegionKindInterface, Symbol, SymbolManager,
-    SymbolManagerMut, SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolUseList,
+    SymbolManagerMut, SymbolMap, SymbolName, SymbolRef, SymbolTable, SymbolTableRef, SymbolUseList,
     UnsafeIntrusiveEntityRef, Usable, Visibility,
 };
 
@@ -57,6 +57,7 @@ pub type ModuleRef = UnsafeIntrusiveEntityRef<Module>;
         HasOnlyGraphRegion,
         GraphRegionNoTerminator,
         IsolatedFromAbove,
+        BelongsInSymbolTable,
     ),
     implements(RegionKindInterface, SymbolTable, Symbol, OpPrinter)
 )]
@@ -176,6 +177,11 @@ impl SymbolTable for Module {
         &self.op
     }
 
+    #[inline(always)]
+    fn as_symbol_table_ref(&self) -> SymbolTableRef {
+        unsafe { SymbolTableRef::from_raw(self) }
+    }
+
     #[inline(always)]
     fn as_symbol_table_operation_mut(&mut self) -> &mut Operation {
         &mut self.op
diff --git a/hir/src/dialects/builtin/ops/world.rs b/hir/src/dialects/builtin/ops/world.rs
index 9a922b632..4dc93cf9e 100644
--- a/hir/src/dialects/builtin/ops/world.rs
+++ b/hir/src/dialects/builtin/ops/world.rs
@@ -6,7 +6,8 @@ use crate::{
         NoTerminator, SingleBlock, SingleRegion,
     },
     Operation, RegionKind, RegionKindInterface, SymbolManager, SymbolManagerMut, SymbolMap,
-    SymbolName, SymbolRef, SymbolTable, SymbolUseList, UnsafeIntrusiveEntityRef, Usable,
+    SymbolName, SymbolRef, SymbolTable, SymbolTableRef, SymbolUseList, UnsafeIntrusiveEntityRef,
+    Usable,
 };
 
 pub type WorldRef = UnsafeIntrusiveEntityRef<World>;
@@ -68,6 +69,11 @@ impl SymbolTable for World {
         &self.op
     }
 
+    #[inline(always)]
+    fn as_symbol_table_ref(&self) -> SymbolTableRef {
+        unsafe { SymbolTableRef::from_raw(self) }
+    }
+
     #[inline(always)]
     fn as_symbol_table_operation_mut(&mut self) -> &mut Operation {
         &mut self.op
diff --git a/hir/src/ir/symbols/table.rs b/hir/src/ir/symbols/table.rs
index 53caba022..ea4017c14 100644
--- a/hir/src/ir/symbols/table.rs
+++ b/hir/src/ir/symbols/table.rs
@@ -23,6 +23,9 @@ pub trait SymbolTable {
     /// Get a reference to the underlying [Operation]
     fn as_symbol_table_operation(&self) -> &Operation;
 
+    /// Get a reference to the underlying [Operation] as a SymbolTable
+    fn as_symbol_table_ref(&self) -> SymbolTableRef;
+
     /// Get a mutable reference to the underlying [Operation]
     fn as_symbol_table_operation_mut(&mut self) -> &mut Operation;
 
diff --git a/hir/src/ir/traits.rs b/hir/src/ir/traits.rs
index d82c6603c..b315d0b85 100644
--- a/hir/src/ir/traits.rs
+++ b/hir/src/ir/traits.rs
@@ -40,6 +40,9 @@ pub trait Involution {}
 /// Marker trait for ops which are not permitted to access values defined above them
 pub trait IsolatedFromAbove {}
 
+/// Marker trait for ops whose parent op needs to add them to their own symbol list.
+pub trait BelongsInSymbolTable {}
+
 /// Marker trait for ops which have only regions of [`RegionKind::Graph`]
 pub trait HasOnlyGraphRegion {}
 
diff --git a/hir/src/matchers/matcher.rs b/hir/src/matchers/matcher.rs
index ba04d4d9d..8491f1881 100644
--- a/hir/src/matchers/matcher.rs
+++ b/hir/src/matchers/matcher.rs
@@ -752,11 +752,16 @@ mod tests {
     fn setup(context: Rc<Context>) -> (ValueRef, ValueRef, ValueRef) {
         let mut builder = OpBuilder::new(Rc::clone(&context));
 
+        let world_ref = builder.create::<World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<Function, (_, _)>(SourceSpan::default());
+            let builder = builder.create::<Function, (_, _, _)>(SourceSpan::default());
             let name = Ident::new("test".into(), SourceSpan::default());
             let signature = Signature::new([AbiParam::new(Type::U32)], [AbiParam::new(Type::U32)]);
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body
diff --git a/hir/src/patterns/pattern.rs b/hir/src/patterns/pattern.rs
index 277a93ae4..5c4b10cc9 100644
--- a/hir/src/patterns/pattern.rs
+++ b/hir/src/patterns/pattern.rs
@@ -327,11 +327,17 @@ mod tests {
         let pattern = ConvertShiftLeftBy1ToMultiply::new(Rc::clone(&context));
 
         let mut builder = OpBuilder::new(Rc::clone(&context));
+
+        let world_ref = builder.create::<World, ()>(Default::default())()
+            .expect("Error unrelated to test: Failed to build world.");
+        let mut world_builder = WorldBuilder::new(world_ref);
+        let world = &mut world_builder.world.borrow_mut().as_symbol_table_ref();
+
         let function = {
-            let builder = builder.create::<Function, (_, _)>(SourceSpan::default());
+            let builder = builder.create::<Function, (_, _, _)>(SourceSpan::default());
             let name = Ident::new("test".into(), SourceSpan::default());
             let signature = Signature::new([AbiParam::new(Type::U32)], [AbiParam::new(Type::U32)]);
-            builder(name, signature).unwrap()
+            builder(name, signature, world).unwrap()
         };
 
         // Define function body
@@ -363,7 +369,7 @@ mod tests {
         let output = func.as_operation().to_string();
         let expected = "\
 public builtin.function @test(v0: u32) -> u32 {
-^block0(v0: u32):
+^block1(v0: u32):
     v3 = test.constant 2 : u32;
     v4 = test.mul v0, v3 : u32 #[overflow = wrapping];
     builtin.ret v4;
diff --git a/tests/integration/src/lib.rs b/tests/integration/src/lib.rs
index 332c4a177..3a7da5321 100644
--- a/tests/integration/src/lib.rs
+++ b/tests/integration/src/lib.rs
@@ -1,7 +1,7 @@
 //! Compilation and semantic tests for the whole compiler pipeline
 #![feature(iter_array_chunks)]
 #![feature(debug_closure_helpers)]
-//#![deny(warnings)]
+#![deny(warnings)]
 #![deny(missing_docs)]
 
 mod cargo_proj;