making sure sliced pointer is loaded

Signed-off-by: Jakub Doka <jakub.doka2@gmail.com>

lang/README.md

@@ -798,6 +798,16 @@ main := fn(): uint {
 
 ### Purely Testing Examples
 
+#### slice_to_global_pointer
+```hb
+a := @as(^u8, @bitcast(0))
+
+main := fn(): ^u8 {
+	b := a[0..100]
+	return b.ptr
+}
+```
+
 #### subsclice_bug
 ```hb
 main := fn(): void {

lang/src/son.rs

@@ -1268,7 +1268,7 @@ impl<'a> Codegen<'a> {
                 }
             }
             Expr::Index { base, index: &Expr::Range { start, end, pos } } => {
-                let bs = self.ptr_expr(base)?;
+                let mut bs = self.ptr_expr(base)?;
 
                 let start = match start {
                     Some(s) => self.checked_expr(s, ty::Id::UINT, "range start")?.id,
@@ -1325,7 +1325,10 @@ impl<'a> Codegen<'a> {
                         let base = self.tys.make_ptr(elem);
                         Value::new(self.load_mem(off, base)).ty(base)
                     }
-                    ty::Kind::Ptr(_) => bs,
+                    ty::Kind::Ptr(_) => {
+                        self.strip_ptr(&mut bs);
+                        bs
+                    }
                     _ => unreachable!(),
                 };
                 ptr.id = self.offset_ptr(ptr.id, elem, start).id;
@@ -4462,6 +4465,7 @@ mod tests {
         fb_driver;
 
         // Purely Testing Examples;
+        slice_to_global_pointer;
         subsclice_bug;
         string_array;
         proper_ident_propagation;

lang/tests/son_tests_slice_to_global_pointer.txt

@@ -0,0 +1,8 @@
+main:
+    LRA r13, r0, :a
+    LD r13, r13, 0a, 8h
+    CP r1, r13
+    JALA r0, r31, 0a
+code size: 50
+ret: 0
+status: Ok(())