From 1a54aaa1c0fa7db604ff5d47b493a5ec7e266a7d Mon Sep 17 00:00:00 2001
From: David Mak <csdavidmak@ust.hk>
Date: Fri, 6 Oct 2023 11:11:38 +0800
Subject: [PATCH] core: Restore debug location when generating allocas

Debug location is lost when moving the builder cursor.
---
 nac3core/src/codegen/mod.rs  |  2 ++
 nac3core/src/codegen/stmt.rs | 15 +++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/nac3core/src/codegen/mod.rs b/nac3core/src/codegen/mod.rs
index 9006a59..28a4d60 100644
--- a/nac3core/src/codegen/mod.rs
+++ b/nac3core/src/codegen/mod.rs
@@ -129,6 +129,8 @@ impl CodeGenTargetMachineOptions {
 pub struct CodeGenContext<'ctx, 'a> {
     pub ctx: &'ctx Context,
     pub builder: Builder<'ctx>,
+    /// The [DebugInfoBuilder], [compilation unit information][DICompileUnit], and
+    /// [scope information][DIScope] of this context.
     pub debug_info: (DebugInfoBuilder<'ctx>, DICompileUnit<'ctx>, DIScope<'ctx>),
     pub module: Module<'ctx>,
     pub top_level: &'a TopLevelContext,
diff --git a/nac3core/src/codegen/stmt.rs b/nac3core/src/codegen/stmt.rs
index 450df82..f737c87 100644
--- a/nac3core/src/codegen/stmt.rs
+++ b/nac3core/src/codegen/stmt.rs
@@ -27,12 +27,27 @@ pub fn gen_var<'ctx, 'a>(
     ty: BasicTypeEnum<'ctx>,
     name: Option<&str>,
 ) -> Result<PointerValue<'ctx>, String> {
+    // Restore debug location
+    let di_loc = ctx.debug_info.0.create_debug_location(
+        ctx.ctx,
+        ctx.current_loc.row as u32,
+        ctx.current_loc.column as u32,
+        ctx.debug_info.2,
+        None,
+    );
+
     // put the alloca in init block
     let current = ctx.builder.get_insert_block().unwrap();
+
     // position before the last branching instruction...
     ctx.builder.position_before(&ctx.init_bb.get_last_instruction().unwrap());
+    ctx.builder.set_current_debug_location(di_loc);
+
     let ptr = ctx.builder.build_alloca(ty, name.unwrap_or(""));
+
     ctx.builder.position_at_end(current);
+    ctx.builder.set_current_debug_location(di_loc);
+
     Ok(ptr)
 }