diff --git a/patches/0001-Pin-compiler_builtins-to-0.1.160.patch b/patches/0001-Pin-compiler_builtins-to-0.1.160.patch
deleted file mode 100644
index 39266e081ed..00000000000
--- a/patches/0001-Pin-compiler_builtins-to-0.1.160.patch
+++ /dev/null
@@ -1,39 +0,0 @@
-From cdb3d407740e4f15c3746051f8ba89b8e74e99d3 Mon Sep 17 00:00:00 2001
-From: None <none@example.com>
-Date: Fri, 30 May 2025 13:46:22 -0400
-Subject: [PATCH] Pin compiler_builtins to 0.1.160
-
----
- library/alloc/Cargo.toml | 2 +-
- library/std/Cargo.toml   | 2 +-
- 2 files changed, 2 insertions(+), 2 deletions(-)
-
-diff --git a/library/alloc/Cargo.toml b/library/alloc/Cargo.toml
-index 9d0d957..365c9dc 100644
---- a/library/alloc/Cargo.toml
-+++ b/library/alloc/Cargo.toml
-@@ -16,7 +16,7 @@ bench = false
- 
- [dependencies]
- core = { path = "../core", public = true }
--compiler_builtins = { version = "=0.1.159", features = ['rustc-dep-of-std'] }
-+compiler_builtins = { version = "=0.1.160", features = ['rustc-dep-of-std'] }
- 
- [features]
- compiler-builtins-mem = ['compiler_builtins/mem']
-diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml
-index 4ff4895..31371f0 100644
---- a/library/std/Cargo.toml
-+++ b/library/std/Cargo.toml
-@@ -18,7 +18,7 @@ cfg-if = { version = "1.0", features = ['rustc-dep-of-std'] }
- panic_unwind = { path = "../panic_unwind", optional = true }
- panic_abort = { path = "../panic_abort" }
- core = { path = "../core", public = true }
--compiler_builtins = { version = "=0.1.159" }
-+compiler_builtins = { version = "=0.1.160" }
- unwind = { path = "../unwind" }
- hashbrown = { version = "0.15", default-features = false, features = [
-     'rustc-dep-of-std',
--- 
-2.49.0
-
diff --git a/rust-toolchain b/rust-toolchain
index bafe497a2a2..8be204c1581 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2025-05-21"
+channel = "nightly-2025-06-02"
 components = ["rust-src", "rustc-dev", "llvm-tools-preview"]
diff --git a/src/abi.rs b/src/abi.rs
index d882d3eecf4..0c499ba6237 100644
--- a/src/abi.rs
+++ b/src/abi.rs
@@ -15,7 +15,6 @@ use rustc_target::callconv::{Conv, RiscvInterruptKind};
 
 use crate::builder::Builder;
 use crate::context::CodegenCx;
-use crate::intrinsic::ArgAbiExt;
 use crate::type_of::LayoutGccExt;
 
 impl AbiBuilderMethods for Builder<'_, '_, '_> {
@@ -125,7 +124,7 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
             PassMode::Direct(_) | PassMode::Pair(..) => self.ret.layout.immediate_gcc_type(cx),
             PassMode::Cast { ref cast, .. } => cast.gcc_type(cx),
             PassMode::Indirect { .. } => {
-                argument_tys.push(cx.type_ptr_to(self.ret.memory_ty(cx)));
+                argument_tys.push(cx.type_ptr_to(self.ret.layout.gcc_type(cx)));
                 cx.type_void()
             }
         };
@@ -176,13 +175,13 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 PassMode::Indirect { attrs: _, meta_attrs: None, on_stack: true } => {
                     // This is a "byval" argument, so we don't apply the `restrict` attribute on it.
                     on_stack_param_indices.insert(argument_tys.len());
-                    arg.memory_ty(cx)
+                    arg.layout.gcc_type(cx)
                 }
                 PassMode::Direct(attrs) => {
                     apply_attrs(arg.layout.immediate_gcc_type(cx), &attrs, argument_tys.len())
                 }
                 PassMode::Indirect { attrs, meta_attrs: None, on_stack: false } => {
-                    apply_attrs(cx.type_ptr_to(arg.memory_ty(cx)), &attrs, argument_tys.len())
+                    apply_attrs(cx.type_ptr_to(arg.layout.gcc_type(cx)), &attrs, argument_tys.len())
                 }
                 PassMode::Indirect { attrs, meta_attrs: Some(meta_attrs), on_stack } => {
                     assert!(!on_stack);
diff --git a/src/base.rs b/src/base.rs
index a9d7808c833..c105916bbb2 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -219,17 +219,22 @@ pub fn compile_codegen_unit(
 
             let mono_items = cgu.items_in_deterministic_order(tcx);
             for &(mono_item, data) in &mono_items {
-                mono_item.predefine::<Builder<'_, '_, '_>>(&cx, data.linkage, data.visibility);
+                mono_item.predefine::<Builder<'_, '_, '_>>(
+                    &mut cx,
+                    cgu_name.as_str(),
+                    data.linkage,
+                    data.visibility,
+                );
             }
 
             // ... and now that we have everything pre-defined, fill out those definitions.
             for &(mono_item, item_data) in &mono_items {
-                mono_item.define::<Builder<'_, '_, '_>>(&mut cx, item_data);
+                mono_item.define::<Builder<'_, '_, '_>>(&mut cx, cgu_name.as_str(), item_data);
             }
 
             // If this codegen unit contains the main function, also create the
             // wrapper here
-            maybe_create_entry_wrapper::<Builder<'_, '_, '_>>(&cx);
+            maybe_create_entry_wrapper::<Builder<'_, '_, '_>>(&cx, cx.codegen_unit);
 
             // Finalize debuginfo
             if cx.sess().opts.debuginfo != DebugInfo::None {
diff --git a/src/builder.rs b/src/builder.rs
index 2ce1a31bebc..96e3773c7c4 100644
--- a/src/builder.rs
+++ b/src/builder.rs
@@ -12,7 +12,7 @@ use rustc_abi::{Align, HasDataLayout, Size, TargetDataLayout, WrappingRange};
 use rustc_apfloat::{Float, Round, Status, ieee};
 use rustc_codegen_ssa::MemFlags;
 use rustc_codegen_ssa::common::{
-    AtomicOrdering, AtomicRmwBinOp, IntPredicate, RealPredicate, SynchronizationScope, TypeKind,
+    AtomicRmwBinOp, IntPredicate, RealPredicate, SynchronizationScope, TypeKind,
 };
 use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::PlaceRef;
@@ -26,7 +26,7 @@ use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTyCtxt, HasTypingEnv, LayoutError, LayoutOfHelpers,
 };
-use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
+use rustc_middle::ty::{self, AtomicOrdering, Instance, Ty, TyCtxt};
 use rustc_span::Span;
 use rustc_span::def_id::DefId;
 use rustc_target::callconv::FnAbi;
@@ -75,7 +75,7 @@ impl<'a, 'gcc, 'tcx> Builder<'a, 'gcc, 'tcx> {
 
         let load_ordering = match order {
             // TODO(antoyo): does this make sense?
-            AtomicOrdering::AcquireRelease | AtomicOrdering::Release => AtomicOrdering::Acquire,
+            AtomicOrdering::AcqRel | AtomicOrdering::Release => AtomicOrdering::Acquire,
             _ => order,
         };
         let previous_value =
@@ -2498,8 +2498,8 @@ impl ToGccOrdering for AtomicOrdering {
             AtomicOrdering::Relaxed => __ATOMIC_RELAXED, // TODO(antoyo): check if that's the same.
             AtomicOrdering::Acquire => __ATOMIC_ACQUIRE,
             AtomicOrdering::Release => __ATOMIC_RELEASE,
-            AtomicOrdering::AcquireRelease => __ATOMIC_ACQ_REL,
-            AtomicOrdering::SequentiallyConsistent => __ATOMIC_SEQ_CST,
+            AtomicOrdering::AcqRel => __ATOMIC_ACQ_REL,
+            AtomicOrdering::SeqCst => __ATOMIC_SEQ_CST,
         };
         ordering as i32
     }
diff --git a/src/consts.rs b/src/consts.rs
index 73d3beede7f..890e5f1e6c9 100644
--- a/src/consts.rs
+++ b/src/consts.rs
@@ -63,7 +63,7 @@ impl<'gcc, 'tcx> StaticCodegenMethods for CodegenCx<'gcc, 'tcx> {
     }
 
     #[cfg_attr(not(feature = "master"), allow(unused_mut))]
-    fn codegen_static(&self, def_id: DefId) {
+    fn codegen_static(&mut self, def_id: DefId) {
         let attrs = self.tcx.codegen_fn_attrs(def_id);
 
         let Ok((value, alloc)) = codegen_static_initializer(self, def_id) else {
@@ -150,25 +150,20 @@ impl<'gcc, 'tcx> StaticCodegenMethods for CodegenCx<'gcc, 'tcx> {
             // TODO(antoyo): set link section.
         }
 
-        if attrs.flags.contains(CodegenFnAttrFlags::USED)
+        if attrs.flags.contains(CodegenFnAttrFlags::USED_COMPILER)
             || attrs.flags.contains(CodegenFnAttrFlags::USED_LINKER)
         {
             self.add_used_global(global.to_rvalue());
         }
     }
+}
 
+impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
     /// Add a global value to a list to be stored in the `llvm.used` variable, an array of i8*.
-    fn add_used_global(&self, _global: RValue<'gcc>) {
+    pub fn add_used_global(&mut self, _global: RValue<'gcc>) {
         // TODO(antoyo)
     }
 
-    fn add_compiler_used_global(&self, global: RValue<'gcc>) {
-        // NOTE: seems like GCC does not make the distinction between compiler.used and used.
-        self.add_used_global(global);
-    }
-}
-
-impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
     #[cfg_attr(not(feature = "master"), allow(unused_variables))]
     pub fn add_used_function(&self, function: Function<'gcc>) {
         #[cfg(feature = "master")]
diff --git a/src/context.rs b/src/context.rs
index 51c2be85d51..1d46d73cd26 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -483,10 +483,6 @@ impl<'gcc, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         self.tcx.sess
     }
 
-    fn codegen_unit(&self) -> &'tcx CodegenUnit<'tcx> {
-        self.codegen_unit
-    }
-
     fn set_frame_pointer_type(&self, _llfn: RValue<'gcc>) {
         // TODO(antoyo)
     }
diff --git a/src/intrinsic/mod.rs b/src/intrinsic/mod.rs
index acecab35d72..a03b4a9c581 100644
--- a/src/intrinsic/mod.rs
+++ b/src/intrinsic/mod.rs
@@ -22,11 +22,11 @@ use rustc_codegen_ssa::traits::{
 };
 use rustc_middle::bug;
 #[cfg(feature = "master")]
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
-use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
+use rustc_middle::ty::layout::FnAbiOf;
+use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::{self, Instance, Ty};
 use rustc_span::{Span, Symbol, sym};
-use rustc_target::callconv::{ArgAbi, FnAbi, PassMode};
+use rustc_target::callconv::{ArgAbi, PassMode};
 use rustc_target::spec::PanicStrategy;
 
 #[cfg(feature = "master")]
@@ -253,28 +253,15 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
     fn codegen_intrinsic_call(
         &mut self,
         instance: Instance<'tcx>,
-        fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
         args: &[OperandRef<'tcx, RValue<'gcc>>],
-        llresult: RValue<'gcc>,
+        result: PlaceRef<'tcx, RValue<'gcc>>,
         span: Span,
     ) -> Result<(), Instance<'tcx>> {
         let tcx = self.tcx;
-        let callee_ty = instance.ty(tcx, self.typing_env());
 
-        let (def_id, fn_args) = match *callee_ty.kind() {
-            ty::FnDef(def_id, fn_args) => (def_id, fn_args),
-            _ => bug!("expected fn item type, found {}", callee_ty),
-        };
-
-        let sig = callee_ty.fn_sig(tcx);
-        let sig = tcx.normalize_erasing_late_bound_regions(self.typing_env(), sig);
-        let arg_tys = sig.inputs();
-        let ret_ty = sig.output();
-        let name = tcx.item_name(def_id);
+        let name = tcx.item_name(instance.def_id());
         let name_str = name.as_str();
-
-        let llret_ty = self.layout_of(ret_ty).gcc_type(self);
-        let result = PlaceRef::new_sized(llresult, fn_abi.ret.layout);
+        let fn_args = instance.args;
 
         let simple = get_simple_intrinsic(self, name);
         let simple_func = get_simple_function(self, name)
@@ -364,7 +351,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
                     args[0].immediate(),
                     args[1].immediate(),
                     args[2].immediate(),
-                    llresult,
+                    result,
                 );
                 return Ok(());
             }
@@ -379,17 +366,10 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
             }
 
             sym::volatile_load | sym::unaligned_volatile_load => {
-                let tp_ty = fn_args.type_at(0);
                 let ptr = args[0].immediate();
-                let layout = self.layout_of(tp_ty);
-                let load = if let PassMode::Cast { cast: ref ty, pad_i32: _ } = fn_abi.ret.mode {
-                    let gcc_ty = ty.gcc_type(self);
-                    self.volatile_load(gcc_ty, ptr)
-                } else {
-                    self.volatile_load(layout.gcc_type(self), ptr)
-                };
+                let load = self.volatile_load(result.layout.gcc_type(self), ptr);
                 // TODO(antoyo): set alignment.
-                if let BackendRepr::Scalar(scalar) = layout.backend_repr {
+                if let BackendRepr::Scalar(scalar) = result.layout.backend_repr {
                     self.to_immediate_scalar(load, scalar)
                 } else {
                     load
@@ -422,8 +402,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
             | sym::rotate_right
             | sym::saturating_add
             | sym::saturating_sub => {
-                let ty = arg_tys[0];
-                match int_type_width_signed(ty, self) {
+                match int_type_width_signed(args[0].layout.ty, self) {
                     Some((width, signed)) => match name {
                         sym::ctlz | sym::cttz => {
                             let func = self.current_func.borrow().expect("func");
@@ -502,7 +481,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
                         tcx.dcx().emit_err(InvalidMonomorphization::BasicIntegerType {
                             span,
                             name,
-                            ty,
+                            ty: args[0].layout.ty,
                         });
                         return Ok(());
                     }
@@ -594,7 +573,14 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
             }
 
             _ if name_str.starts_with("simd_") => {
-                match generic_simd_intrinsic(self, name, callee_ty, args, ret_ty, llret_ty, span) {
+                match generic_simd_intrinsic(
+                    self,
+                    name,
+                    args,
+                    result.layout.ty,
+                    result.layout.gcc_type(self),
+                    span,
+                ) {
                     Ok(value) => value,
                     Err(()) => return Ok(()),
                 }
@@ -604,16 +590,11 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
             _ => return Err(Instance::new_raw(instance.def_id(), instance.args)),
         };
 
-        if !fn_abi.ret.is_ignore() {
-            if let PassMode::Cast { cast: ref ty, .. } = fn_abi.ret.mode {
-                let ptr_llty = self.type_ptr_to(ty.gcc_type(self));
-                let ptr = self.pointercast(result.val.llval, ptr_llty);
-                self.store(value, ptr, result.val.align);
-            } else {
-                OperandRef::from_immediate_or_packed_pair(self, value, result.layout)
-                    .val
-                    .store(self, result);
-            }
+        if result.layout.ty.is_bool() {
+            let val = self.from_immediate(value);
+            self.store_to_place(val, result.val);
+        } else if !result.layout.ty.is_unit() {
+            self.store_to_place(value, result.val);
         }
         Ok(())
     }
@@ -678,14 +659,9 @@ impl<'a, 'gcc, 'tcx> ArgAbiBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
     ) {
         arg_abi.store(self, val, dst)
     }
-
-    fn arg_memory_ty(&self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>) -> Type<'gcc> {
-        arg_abi.memory_ty(self)
-    }
 }
 
 pub trait ArgAbiExt<'gcc, 'tcx> {
-    fn memory_ty(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc>;
     fn store(
         &self,
         bx: &mut Builder<'_, 'gcc, 'tcx>,
@@ -701,12 +677,6 @@ pub trait ArgAbiExt<'gcc, 'tcx> {
 }
 
 impl<'gcc, 'tcx> ArgAbiExt<'gcc, 'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
-    /// Gets the LLVM type for a place of the original Rust type of
-    /// this argument/return, i.e., the result of `type_of::type_of`.
-    fn memory_ty(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> {
-        self.layout.gcc_type(cx)
-    }
-
     /// Stores a direct/indirect value described by this ArgAbi into a
     /// place for the original Rust type of this argument/return.
     /// Can be used for both storing formal arguments into Rust variables
@@ -1323,14 +1293,13 @@ fn try_intrinsic<'a, 'b, 'gcc, 'tcx>(
     try_func: RValue<'gcc>,
     data: RValue<'gcc>,
     _catch_func: RValue<'gcc>,
-    dest: RValue<'gcc>,
+    dest: PlaceRef<'tcx, RValue<'gcc>>,
 ) {
     if bx.sess().panic_strategy() == PanicStrategy::Abort {
         bx.call(bx.type_void(), None, None, try_func, &[data], None, None);
         // Return 0 unconditionally from the intrinsic call;
         // we can never unwind.
-        let ret_align = bx.tcx.data_layout.i32_align.abi;
-        bx.store(bx.const_i32(0), dest, ret_align);
+        OperandValue::Immediate(bx.const_i32(0)).store(bx, dest);
     } else {
         if wants_msvc_seh(bx.sess()) {
             unimplemented!();
@@ -1354,12 +1323,12 @@ fn try_intrinsic<'a, 'b, 'gcc, 'tcx>(
 // functions in play. By calling a shim we're guaranteed that our shim will have
 // the right personality function.
 #[cfg(feature = "master")]
-fn codegen_gnu_try<'gcc>(
-    bx: &mut Builder<'_, 'gcc, '_>,
+fn codegen_gnu_try<'gcc, 'tcx>(
+    bx: &mut Builder<'_, 'gcc, 'tcx>,
     try_func: RValue<'gcc>,
     data: RValue<'gcc>,
     catch_func: RValue<'gcc>,
-    dest: RValue<'gcc>,
+    dest: PlaceRef<'tcx, RValue<'gcc>>,
 ) {
     let cx: &CodegenCx<'gcc, '_> = bx.cx;
     let (llty, func) = get_rust_try_fn(cx, &mut |mut bx| {
@@ -1415,8 +1384,7 @@ fn codegen_gnu_try<'gcc>(
     // Note that no invoke is used here because by definition this function
     // can't panic (that's what it's catching).
     let ret = bx.call(llty, None, None, func, &[try_func, data, catch_func], None, None);
-    let i32_align = bx.tcx().data_layout.i32_align.abi;
-    bx.store(ret, dest, i32_align);
+    OperandValue::Immediate(ret).store(bx, dest);
 }
 
 // Helper function used to get a handle to the `__rust_try` function used to
diff --git a/src/intrinsic/simd.rs b/src/intrinsic/simd.rs
index b897d079249..82ef0d0b13a 100644
--- a/src/intrinsic/simd.rs
+++ b/src/intrinsic/simd.rs
@@ -28,7 +28,6 @@ use crate::context::CodegenCx;
 pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
     bx: &mut Builder<'a, 'gcc, 'tcx>,
     name: Symbol,
-    callee_ty: Ty<'tcx>,
     args: &[OperandRef<'tcx, RValue<'gcc>>],
     ret_ty: Ty<'tcx>,
     llret_ty: Type<'gcc>,
@@ -54,24 +53,17 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         };
     }
 
-    let tcx = bx.tcx();
-    let sig = tcx.normalize_erasing_late_bound_regions(
-        ty::TypingEnv::fully_monomorphized(),
-        callee_ty.fn_sig(tcx),
-    );
-    let arg_tys = sig.inputs();
-
     if name == sym::simd_select_bitmask {
         require_simd!(
-            arg_tys[1],
-            InvalidMonomorphization::SimdArgument { span, name, ty: arg_tys[1] }
+            args[1].layout.ty,
+            InvalidMonomorphization::SimdArgument { span, name, ty: args[1].layout.ty }
         );
-        let (len, _) = arg_tys[1].simd_size_and_type(bx.tcx());
+        let (len, _) = args[1].layout.ty.simd_size_and_type(bx.tcx());
 
         let expected_int_bits = (len.max(8) - 1).next_power_of_two();
         let expected_bytes = len / 8 + ((len % 8 > 0) as u64);
 
-        let mask_ty = arg_tys[0];
+        let mask_ty = args[0].layout.ty;
         let mut mask = match *mask_ty.kind() {
             ty::Int(i) if i.bit_width() == Some(expected_int_bits) => args[0].immediate(),
             ty::Uint(i) if i.bit_width() == Some(expected_int_bits) => args[0].immediate(),
@@ -121,8 +113,11 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
     }
 
     // every intrinsic below takes a SIMD vector as its first argument
-    require_simd!(arg_tys[0], InvalidMonomorphization::SimdInput { span, name, ty: arg_tys[0] });
-    let in_ty = arg_tys[0];
+    require_simd!(
+        args[0].layout.ty,
+        InvalidMonomorphization::SimdInput { span, name, ty: args[0].layout.ty }
+    );
+    let in_ty = args[0].layout.ty;
 
     let comparison = match name {
         sym::simd_eq => Some(BinOp::Eq),
@@ -134,7 +129,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         _ => None,
     };
 
-    let (in_len, in_elem) = arg_tys[0].simd_size_and_type(bx.tcx());
+    let (in_len, in_elem) = args[0].layout.ty.simd_size_and_type(bx.tcx());
     if let Some(cmp_op) = comparison {
         require_simd!(ret_ty, InvalidMonomorphization::SimdReturn { span, name, ty: ret_ty });
 
@@ -401,13 +396,13 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
     #[cfg(feature = "master")]
     if name == sym::simd_insert || name == sym::simd_insert_dyn {
         require!(
-            in_elem == arg_tys[2],
+            in_elem == args[2].layout.ty,
             InvalidMonomorphization::InsertedType {
                 span,
                 name,
                 in_elem,
                 in_ty,
-                out_ty: arg_tys[2]
+                out_ty: args[2].layout.ty
             }
         );
 
@@ -439,10 +434,10 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         let m_elem_ty = in_elem;
         let m_len = in_len;
         require_simd!(
-            arg_tys[1],
-            InvalidMonomorphization::SimdArgument { span, name, ty: arg_tys[1] }
+            args[1].layout.ty,
+            InvalidMonomorphization::SimdArgument { span, name, ty: args[1].layout.ty }
         );
-        let (v_len, _) = arg_tys[1].simd_size_and_type(bx.tcx());
+        let (v_len, _) = args[1].layout.ty.simd_size_and_type(bx.tcx());
         require!(
             m_len == v_len,
             InvalidMonomorphization::MismatchedLengths { span, name, m_len, v_len }
@@ -911,18 +906,18 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         // All types must be simd vector types
         require_simd!(in_ty, InvalidMonomorphization::SimdFirst { span, name, ty: in_ty });
         require_simd!(
-            arg_tys[1],
-            InvalidMonomorphization::SimdSecond { span, name, ty: arg_tys[1] }
+            args[1].layout.ty,
+            InvalidMonomorphization::SimdSecond { span, name, ty: args[1].layout.ty }
         );
         require_simd!(
-            arg_tys[2],
-            InvalidMonomorphization::SimdThird { span, name, ty: arg_tys[2] }
+            args[2].layout.ty,
+            InvalidMonomorphization::SimdThird { span, name, ty: args[2].layout.ty }
         );
         require_simd!(ret_ty, InvalidMonomorphization::SimdReturn { span, name, ty: ret_ty });
 
         // Of the same length:
-        let (out_len, _) = arg_tys[1].simd_size_and_type(bx.tcx());
-        let (out_len2, _) = arg_tys[2].simd_size_and_type(bx.tcx());
+        let (out_len, _) = args[1].layout.ty.simd_size_and_type(bx.tcx());
+        let (out_len2, _) = args[2].layout.ty.simd_size_and_type(bx.tcx());
         require!(
             in_len == out_len,
             InvalidMonomorphization::SecondArgumentLength {
@@ -930,7 +925,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                 name,
                 in_len,
                 in_ty,
-                arg_ty: arg_tys[1],
+                arg_ty: args[1].layout.ty,
                 out_len
             }
         );
@@ -941,7 +936,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                 name,
                 in_len,
                 in_ty,
-                arg_ty: arg_tys[2],
+                arg_ty: args[2].layout.ty,
                 out_len: out_len2
             }
         );
@@ -970,8 +965,8 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
 
         // The second argument must be a simd vector with an element type that's a pointer
         // to the element type of the first argument
-        let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx());
-        let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx());
+        let (_, element_ty0) = args[0].layout.ty.simd_size_and_type(bx.tcx());
+        let (_, element_ty1) = args[1].layout.ty.simd_size_and_type(bx.tcx());
         let (pointer_count, underlying_ty) = match *element_ty1.kind() {
             ty::RawPtr(p_ty, _) if p_ty == in_elem => {
                 (ptr_count(element_ty1), non_ptr(element_ty1))
@@ -983,7 +978,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                         span,
                         name,
                         expected_element: element_ty1,
-                        second_arg: arg_tys[1],
+                        second_arg: args[1].layout.ty,
                         in_elem,
                         in_ty,
                         mutability: ExpectedPointerMutability::Not,
@@ -998,7 +993,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
 
         // The element type of the third argument must be an integer type of any width:
         // TODO: also support unsigned integers.
-        let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx());
+        let (_, element_ty2) = args[2].layout.ty.simd_size_and_type(bx.tcx());
         match *element_ty2.kind() {
             ty::Int(_) => (),
             _ => {
@@ -1030,17 +1025,17 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         // All types must be simd vector types
         require_simd!(in_ty, InvalidMonomorphization::SimdFirst { span, name, ty: in_ty });
         require_simd!(
-            arg_tys[1],
-            InvalidMonomorphization::SimdSecond { span, name, ty: arg_tys[1] }
+            args[1].layout.ty,
+            InvalidMonomorphization::SimdSecond { span, name, ty: args[1].layout.ty }
         );
         require_simd!(
-            arg_tys[2],
-            InvalidMonomorphization::SimdThird { span, name, ty: arg_tys[2] }
+            args[2].layout.ty,
+            InvalidMonomorphization::SimdThird { span, name, ty: args[2].layout.ty }
         );
 
         // Of the same length:
-        let (element_len1, _) = arg_tys[1].simd_size_and_type(bx.tcx());
-        let (element_len2, _) = arg_tys[2].simd_size_and_type(bx.tcx());
+        let (element_len1, _) = args[1].layout.ty.simd_size_and_type(bx.tcx());
+        let (element_len2, _) = args[2].layout.ty.simd_size_and_type(bx.tcx());
         require!(
             in_len == element_len1,
             InvalidMonomorphization::SecondArgumentLength {
@@ -1048,7 +1043,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                 name,
                 in_len,
                 in_ty,
-                arg_ty: arg_tys[1],
+                arg_ty: args[1].layout.ty,
                 out_len: element_len1
             }
         );
@@ -1059,7 +1054,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                 name,
                 in_len,
                 in_ty,
-                arg_ty: arg_tys[2],
+                arg_ty: args[2].layout.ty,
                 out_len: element_len2
             }
         );
@@ -1082,9 +1077,9 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
 
         // The second argument must be a simd vector with an element type that's a pointer
         // to the element type of the first argument
-        let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx());
-        let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx());
-        let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx());
+        let (_, element_ty0) = args[0].layout.ty.simd_size_and_type(bx.tcx());
+        let (_, element_ty1) = args[1].layout.ty.simd_size_and_type(bx.tcx());
+        let (_, element_ty2) = args[2].layout.ty.simd_size_and_type(bx.tcx());
         let (pointer_count, underlying_ty) = match *element_ty1.kind() {
             ty::RawPtr(p_ty, mutbl) if p_ty == in_elem && mutbl == hir::Mutability::Mut => {
                 (ptr_count(element_ty1), non_ptr(element_ty1))
@@ -1096,7 +1091,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                         span,
                         name,
                         expected_element: element_ty1,
-                        second_arg: arg_tys[1],
+                        second_arg: args[1].layout.ty,
                         in_elem,
                         in_ty,
                         mutability: ExpectedPointerMutability::Mut,
@@ -1194,8 +1189,8 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
                 return_error!(InvalidMonomorphization::ExpectedVectorElementType {
                     span,
                     name,
-                    expected_element: arg_tys[0].simd_size_and_type(bx.tcx()).1,
-                    vector_type: arg_tys[0],
+                    expected_element: args[0].layout.ty.simd_size_and_type(bx.tcx()).1,
+                    vector_type: args[0].layout.ty,
                 });
             }
         };
diff --git a/src/lib.rs b/src/lib.rs
index 66e9ce4627c..d2977ea44f7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -391,7 +391,7 @@ impl WriteBackendMethods for GccCodegenBackend {
         unimplemented!()
     }
 
-    unsafe fn optimize(
+    fn optimize(
         _cgcx: &CodegenContext<Self>,
         _dcx: DiagCtxtHandle<'_>,
         module: &mut ModuleCodegen<Self::Module>,
@@ -409,14 +409,14 @@ impl WriteBackendMethods for GccCodegenBackend {
         Ok(())
     }
 
-    unsafe fn optimize_thin(
+    fn optimize_thin(
         cgcx: &CodegenContext<Self>,
         thin: ThinModule<Self>,
     ) -> Result<ModuleCodegen<Self::Module>, FatalError> {
         back::lto::optimize_thin_module(thin, cgcx)
     }
 
-    unsafe fn codegen(
+    fn codegen(
         cgcx: &CodegenContext<Self>,
         dcx: DiagCtxtHandle<'_>,
         module: ModuleCodegen<Self::Module>,
diff --git a/src/mono_item.rs b/src/mono_item.rs
index a2df7b2596f..539e3ac8507 100644
--- a/src/mono_item.rs
+++ b/src/mono_item.rs
@@ -16,7 +16,7 @@ use crate::{attributes, base};
 impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     #[cfg_attr(not(feature = "master"), allow(unused_variables))]
     fn predefine_static(
-        &self,
+        &mut self,
         def_id: DefId,
         _linkage: Linkage,
         visibility: Visibility,
@@ -42,7 +42,7 @@ impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
 
     #[cfg_attr(not(feature = "master"), allow(unused_variables))]
     fn predefine_fn(
-        &self,
+        &mut self,
         instance: Instance<'tcx>,
         linkage: Linkage,
         visibility: Visibility,