use the llvm offset calculation for struct index

Author: ghaith

src/codegen/debug.rs

@@ -303,7 +303,6 @@ impl<'ink> DebugBuilder<'ink> {
             .unwrap_or_else(|| self.compile_unit.get_file());
 
         let mut types = vec![];
-        let mut offset = 0; //self.target_data.offset_of_element(&struct_type, element_index as u32).unwrap_or(0);
         for (element_index, (member_name, dt, location)) in index_types.into_iter().enumerate() {
             let di_type = self.get_or_create_debug_type(dt, index, types_index)?;
 
@@ -312,6 +311,9 @@ impl<'ink> DebugBuilder<'ink> {
                 .find_associated_type(dt.get_name())
                 .map(|llvm_type| self.target_data.get_bit_size(&llvm_type))
                 .unwrap_or(0);
+            //Offset in bits
+            let offset =
+                self.target_data.offset_of_element(&struct_type, element_index as u32).unwrap_or(0) * 8;
 
             types.push(
                 self.debug_info
@@ -328,7 +330,6 @@ impl<'ink> DebugBuilder<'ink> {
                     )
                     .as_type(),
             );
-            offset += size;
         }
 
         let size = self.target_data.get_bit_size(&struct_type);

src/codegen/tests/snapshots/rusty__codegen__tests__debug_tests__global_var_nested_struct_added_to_debug_info.snap

@@ -46,11 +46,11 @@ entry:
 !4 = !{!5, !7}
 !5 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !2, file: !2, line: 3, baseType: !6, size: 32, flags: DIFlagPublic)
 !6 = !DIBasicType(name: "DINT", size: 32, encoding: DW_ATE_signed, flags: DIFlagPublic)
-!7 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 4, baseType: !8, size: 128, offset: 32, flags: DIFlagPublic)
+!7 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 4, baseType: !8, size: 128, offset: 64, flags: DIFlagPublic)
 !8 = !DICompositeType(tag: DW_TAG_structure_type, name: "myStruct2", scope: !2, file: !2, line: 8, size: 128, flags: DIFlagPublic, elements: !9, identifier: "myStruct2")
 !9 = !{!10, !11}
 !10 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !2, file: !2, line: 9, baseType: !6, size: 32, flags: DIFlagPublic)
-!11 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 10, baseType: !12, size: 64, offset: 32, flags: DIFlagPublic)
+!11 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 10, baseType: !12, size: 64, offset: 64, flags: DIFlagPublic)
 !12 = !DIBasicType(name: "LREAL", size: 64, encoding: DW_ATE_float, flags: DIFlagPublic)
 !13 = !DIGlobalVariableExpression(var: !14, expr: !DIExpression())
 !14 = distinct !DIGlobalVariable(name: "__myStruct2__init", scope: !2, file: !2, line: 8, type: !8, isLocal: false, isDefinition: true)

src/codegen/tests/snapshots/rusty__codegen__tests__debug_tests__global_var_struct_added_to_debug_info.snap

@@ -36,9 +36,9 @@ entry:
 !5 = !{!6, !8, !10}
 !6 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !2, file: !2, line: 3, baseType: !7, size: 32, flags: DIFlagPublic)
 !7 = !DIBasicType(name: "DINT", size: 32, encoding: DW_ATE_signed, flags: DIFlagPublic)
-!8 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 4, baseType: !9, size: 64, offset: 32, flags: DIFlagPublic)
+!8 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !2, file: !2, line: 4, baseType: !9, size: 64, offset: 64, flags: DIFlagPublic)
 !9 = !DIBasicType(name: "LREAL", size: 64, encoding: DW_ATE_float, flags: DIFlagPublic)
-!10 = !DIDerivedType(tag: DW_TAG_member, name: "c", scope: !2, file: !2, line: 5, baseType: !11, size: 352, offset: 96, flags: DIFlagPublic)
+!10 = !DIDerivedType(tag: DW_TAG_member, name: "c", scope: !2, file: !2, line: 5, baseType: !11, size: 352, offset: 128, flags: DIFlagPublic)
 !11 = !DICompositeType(tag: DW_TAG_array_type, baseType: !7, size: 352, elements: !12)
 !12 = !{!13}
 !13 = !DISubrange(count: 11, lowerBound: 0)

src/typesystem.rs

@@ -6,7 +6,6 @@ use std::{
 };
 
 use anyhow::{anyhow, Result};
-use inkwell::types::StructType;
 use plc_ast::{
     ast::{AstNode, AutoDerefType, Operator, PouType, TypeNature},
     literals::{AstLiteral, StringValue},