more ZST fixes

luminalang · Dec 1, 2024 · 9c0d11f · 9c0d11f
1 parent 17d972e
commit 9c0d11f
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Showing 3 changed files with 8 additions and 2 deletions.
diff --git a/lumina-compiler/src/backend/cranelift/layout.rs b/lumina-compiler/src/backend/cranelift/layout.rs
@@ -594,9 +594,12 @@ impl<'a> Structs<'a> {
         }
 
         let (_, align) = self.size_and_align_of_field(&struct_.fields[field]);
-        let end_padding = (align - offset % align) % align;
+        if align != 0 {
+            let end_padding = (align - offset % align) % align;
+            offset += end_padding;
+        }
 
-        ByteOffset(end_padding + offset)
+        ByteOffset(offset)
     }
 
     fn calculate_align_of(&mut self, ty: &MonoType) -> u32 {

diff --git a/lumina-compiler/src/backend/cranelift/mod.rs b/lumina-compiler/src/backend/cranelift/mod.rs
@@ -37,6 +37,7 @@ pub fn run(target: Target, dwarf: BinDebugInfo, lir: lir::Output) -> Vec<u8> {
     shared_builder.set("opt_level", "speed").unwrap();
     shared_builder.enable("preserve_frame_pointers").unwrap();
     shared_builder.enable("unwind_info").unwrap();
+    shared_builder.enable("alias_analysis").unwrap();
     let shared_flags = settings::Flags::new(shared_builder);
     assert!(shared_flags.unwind_info());
 

diff --git a/lumina-compiler/src/backend/cranelift/ssa/record.rs b/lumina-compiler/src/backend/cranelift/ssa/record.rs
@@ -92,6 +92,8 @@ impl<'f, 's, 'a> InstHelper<'f, 's, 'a> {
             }
 
             Layout::AutoBoxed(ty, ptr) => self.field_of_structptr(ty.as_key(), ptr, field),
+            // We can't assert here so I really hope we're never accidentally constructing ZST incorrectly
+            Layout::ZST => VLayout::ZST,
             other => panic!("field of non-struct: {other:?}"),
         }
     }