Add custom driver

[rust.git] / src / vtable.rs

diff --git a/src/vtable.rs b/src/vtable.rs
index 686d23c5d4be7fde2a11f1d80d80914f866af493..d6bb9c912b557a449d004e4ac4b6c8be60420756 100644 (file)
--- a/src/vtable.rs
+++ b/src/vtable.rs
@@ -1,4 +1,7 @@
+//! Codegen vtables and vtable accesses.
+//!
 //! See librustc_codegen_llvm/meth.rs for reference
+// FIXME dedup this logic between miri, cg_llvm and cg_clif
 
 use crate::prelude::*;
 
@@ -51,10 +54,7 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
         arg.load_scalar_pair(fx)
     } else {
         let (ptr, vtable) = arg.try_to_ptr().unwrap();
-        (
-            ptr.get_addr(fx),
-            vtable.unwrap()
-        )
+        (ptr.get_addr(fx), vtable.unwrap())
     };
 
     let usize_size = fx.layout_of(fx.tcx.types.usize).size.bytes();
@@ -92,8 +92,11 @@ fn build_vtable<'tcx>(
     let tcx = fx.tcx;
     let usize_size = fx.layout_of(fx.tcx.types.usize).size.bytes() as usize;
 
-    let drop_in_place_fn =
-        import_function(tcx, &mut fx.cx.module, Instance::resolve_drop_in_place(tcx, layout.ty).polymorphize(fx.tcx));
+    let drop_in_place_fn = import_function(
+        tcx,
+        &mut fx.cx.module,
+        Instance::resolve_drop_in_place(tcx, layout.ty).polymorphize(fx.tcx),
+    );
 
     let mut components: Vec<_> = vec![Some(drop_in_place_fn), None, None];
 
@@ -109,7 +112,9 @@ fn build_vtable<'tcx>(
             Some(import_function(
                 tcx,
                 &mut fx.cx.module,
-                Instance::resolve_for_vtable(tcx, ParamEnv::reveal_all(), def_id, substs).unwrap().polymorphize(fx.tcx),
+                Instance::resolve_for_vtable(tcx, ParamEnv::reveal_all(), def_id, substs)
+                    .unwrap()
+                    .polymorphize(fx.tcx),
             ))
         })
     });
@@ -133,7 +138,8 @@ fn build_vtable<'tcx>(
     }
 
     let data_id = fx
-        .cx.module
+        .cx
+        .module
         .declare_data(
             &format!(
                 "__vtable.{}.for.{:?}.{}",
@@ -165,18 +171,23 @@ fn build_vtable<'tcx>(
 }
 
 fn write_usize(tcx: TyCtxt<'_>, buf: &mut [u8], idx: usize, num: u64) {
-    use byteorder::{BigEndian, LittleEndian, WriteBytesExt};
-
-    let usize_size = tcx
+    let pointer_size = tcx
         .layout_of(ParamEnv::reveal_all().and(tcx.types.usize))
         .unwrap()
         .size
         .bytes() as usize;
-    let mut target = &mut buf[idx * usize_size..(idx + 1) * usize_size];
+    let target = &mut buf[idx * pointer_size..(idx + 1) * pointer_size];
 
     match tcx.data_layout.endian {
-        rustc_target::abi::Endian::Little => target.write_uint::<LittleEndian>(num, usize_size),
-        rustc_target::abi::Endian::Big => target.write_uint::<BigEndian>(num, usize_size),
+        rustc_target::abi::Endian::Little => match pointer_size {
+            4 => target.copy_from_slice(&(num as u32).to_le_bytes()),
+            8 => target.copy_from_slice(&(num as u64).to_le_bytes()),
+            _ => todo!("pointer size {} is not yet supported", pointer_size),
+        },
+        rustc_target::abi::Endian::Big => match pointer_size {
+            4 => target.copy_from_slice(&(num as u32).to_be_bytes()),
+            8 => target.copy_from_slice(&(num as u64).to_be_bytes()),
+            _ => todo!("pointer size {} is not yet supported", pointer_size),
+        },
     }
-    .unwrap()
 }