Auto merge of #52461 - irinagpopa:safe-llvm, r=nikomatsakis

 rustc_codegen_llvm: use safe references for LLVM FFI types.

Part of #45274.

src/Cargo.lock

@@ -2222,11 +2222,8 @@ dependencies = [
 name = "rustc_llvm"
 version = "0.0.0"
 dependencies = [
- "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "build_helper 0.1.0",
  "cc 1.0.18 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.42 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc_cratesio_shim 0.0.0",
 ]
 
 [[package]]

src/librustc_codegen_llvm/abi.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use llvm::{self, ValueRef, AttributePlace};
+use llvm::{self, AttributePlace};
 use base;
 use builder::{Builder, MemFlags};
 use common::{ty_fn_sig, C_usize};
@@ -17,6 +17,7 @@ use mir::place::PlaceRef;
 use mir::operand::OperandValue;
 use type_::Type;
 use type_of::{LayoutLlvmExt, PointerKind};
+use value::Value;
 
 use rustc_target::abi::{LayoutOf, Size, TyLayout};
 use rustc::ty::{self, Ty};
@@ -46,12 +47,12 @@ impl ArgAttributeExt for ArgAttribute {
 }
 
 pub trait ArgAttributesExt {
-    fn apply_llfn(&self, idx: AttributePlace, llfn: ValueRef);
-    fn apply_callsite(&self, idx: AttributePlace, callsite: ValueRef);
+    fn apply_llfn(&self, idx: AttributePlace, llfn: &Value);
+    fn apply_callsite(&self, idx: AttributePlace, callsite: &Value);
 }
 
 impl ArgAttributesExt for ArgAttributes {
-    fn apply_llfn(&self, idx: AttributePlace, llfn: ValueRef) {
+    fn apply_llfn(&self, idx: AttributePlace, llfn: &Value) {
         let mut regular = self.regular;
         unsafe {
             let deref = self.pointee_size.bytes();
@@ -76,7 +77,7 @@ impl ArgAttributesExt for ArgAttributes {
         }
     }
 
-    fn apply_callsite(&self, idx: AttributePlace, callsite: ValueRef) {
+    fn apply_callsite(&self, idx: AttributePlace, callsite: &Value) {
         let mut regular = self.regular;
         unsafe {
             let deref = self.pointee_size.bytes();
@@ -103,11 +104,11 @@ impl ArgAttributesExt for ArgAttributes {
 }
 
 pub trait LlvmType {
-    fn llvm_type(&self, cx: &CodegenCx) -> Type;
+    fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type;
 }
 
 impl LlvmType for Reg {
-    fn llvm_type(&self, cx: &CodegenCx) -> Type {
+    fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type {
         match self.kind {
             RegKind::Integer => Type::ix(cx, self.size.bits()),
             RegKind::Float => {
@@ -118,14 +119,14 @@ impl LlvmType for Reg {
                 }
             }
             RegKind::Vector => {
-                Type::vector(&Type::i8(cx), self.size.bytes())
+                Type::vector(Type::i8(cx), self.size.bytes())
             }
         }
     }
 }
 
 impl LlvmType for CastTarget {
-    fn llvm_type(&self, cx: &CodegenCx) -> Type {
+    fn llvm_type(&self, cx: &CodegenCx<'ll, '_>) -> &'ll Type {
         let rest_ll_unit = self.rest.unit.llvm_type(cx);
         let (rest_count, rem_bytes) = if self.rest.unit.size.bytes() == 0 {
             (0, 0)
@@ -142,7 +143,7 @@ impl LlvmType for CastTarget {
 
             // Simplify to array when all chunks are the same size and type
             if rem_bytes == 0 {
-                return Type::array(&rest_ll_unit, rest_count);
+                return Type::array(rest_ll_unit, rest_count);
             }
         }
 
@@ -164,24 +165,24 @@ impl LlvmType for CastTarget {
     }
 }
 
-pub trait ArgTypeExt<'a, 'tcx> {
-    fn memory_ty(&self, cx: &CodegenCx<'a, 'tcx>) -> Type;
-    fn store(&self, bx: &Builder<'a, 'tcx>, val: ValueRef, dst: PlaceRef<'tcx>);
-    fn store_fn_arg(&self, bx: &Builder<'a, 'tcx>, idx: &mut usize, dst: PlaceRef<'tcx>);
+pub trait ArgTypeExt<'ll, 'tcx> {
+    fn memory_ty(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
+    fn store(&self, bx: &Builder<'_, 'll, 'tcx>, val: &'ll Value, dst: PlaceRef<'ll, 'tcx>);
+    fn store_fn_arg(&self, bx: &Builder<'_, 'll, 'tcx>, idx: &mut usize, dst: PlaceRef<'ll, 'tcx>);
 }
 
-impl<'a, 'tcx> ArgTypeExt<'a, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
+impl ArgTypeExt<'ll, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
     /// Get 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<'a, 'tcx>) -> Type {
+    fn memory_ty(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type {
         self.layout.llvm_type(cx)
     }
 
     /// Store a direct/indirect value described by this ArgType into a
     /// place for the original Rust type of this argument/return.
     /// Can be used for both storing formal arguments into Rust variables
     /// or results of call/invoke instructions into their destinations.
-    fn store(&self, bx: &Builder<'a, 'tcx>, val: ValueRef, dst: PlaceRef<'tcx>) {
+    fn store(&self, bx: &Builder<'_, 'll, 'tcx>, val: &'ll Value, dst: PlaceRef<'ll, 'tcx>) {
         if self.is_ignore() {
             return;
         }
@@ -234,7 +235,7 @@ impl<'a, 'tcx> ArgTypeExt<'a, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
         }
     }
 
-    fn store_fn_arg(&self, bx: &Builder<'a, 'tcx>, idx: &mut usize, dst: PlaceRef<'tcx>) {
+    fn store_fn_arg(&self, bx: &Builder<'a, 'll, 'tcx>, idx: &mut usize, dst: PlaceRef<'ll, 'tcx>) {
         let mut next = || {
             let val = llvm::get_param(bx.llfn(), *idx as c_uint);
             *idx += 1;
@@ -252,48 +253,48 @@ impl<'a, 'tcx> ArgTypeExt<'a, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
     }
 }
 
-pub trait FnTypeExt<'a, 'tcx> {
-    fn of_instance(cx: &CodegenCx<'a, 'tcx>, instance: &ty::Instance<'tcx>)
+pub trait FnTypeExt<'tcx> {
+    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>)
                    -> Self;
-    fn new(cx: &CodegenCx<'a, 'tcx>,
+    fn new(cx: &CodegenCx<'ll, 'tcx>,
            sig: ty::FnSig<'tcx>,
            extra_args: &[Ty<'tcx>]) -> Self;
-    fn new_vtable(cx: &CodegenCx<'a, 'tcx>,
+    fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
                   sig: ty::FnSig<'tcx>,
                   extra_args: &[Ty<'tcx>]) -> Self;
     fn new_internal(
-        cx: &CodegenCx<'a, 'tcx>,
+        cx: &CodegenCx<'ll, 'tcx>,
         sig: ty::FnSig<'tcx>,
         extra_args: &[Ty<'tcx>],
         mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
     ) -> Self;
     fn adjust_for_abi(&mut self,
-                      cx: &CodegenCx<'a, 'tcx>,
+                      cx: &CodegenCx<'ll, 'tcx>,
                       abi: Abi);
-    fn llvm_type(&self, cx: &CodegenCx<'a, 'tcx>) -> Type;
+    fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
     fn llvm_cconv(&self) -> llvm::CallConv;
-    fn apply_attrs_llfn(&self, llfn: ValueRef);
-    fn apply_attrs_callsite(&self, bx: &Builder<'a, 'tcx>, callsite: ValueRef);
+    fn apply_attrs_llfn(&self, llfn: &'ll Value);
+    fn apply_attrs_callsite(&self, bx: &Builder<'a, 'll, 'tcx>, callsite: &'ll Value);
 }
 
-impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
-    fn of_instance(cx: &CodegenCx<'a, 'tcx>, instance: &ty::Instance<'tcx>)
+impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
+    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>)
                        -> Self {
         let fn_ty = instance.ty(cx.tcx);
         let sig = ty_fn_sig(cx, fn_ty);
         let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
         FnType::new(cx, sig, &[])
     }
 
-    fn new(cx: &CodegenCx<'a, 'tcx>,
+    fn new(cx: &CodegenCx<'ll, 'tcx>,
                sig: ty::FnSig<'tcx>,
                extra_args: &[Ty<'tcx>]) -> Self {
         FnType::new_internal(cx, sig, extra_args, |ty, _| {
             ArgType::new(cx.layout_of(ty))
         })
     }
 
-    fn new_vtable(cx: &CodegenCx<'a, 'tcx>,
+    fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
                       sig: ty::FnSig<'tcx>,
                       extra_args: &[Ty<'tcx>]) -> Self {
         FnType::new_internal(cx, sig, extra_args, |ty, arg_idx| {
@@ -316,7 +317,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
     }
 
     fn new_internal(
-        cx: &CodegenCx<'a, 'tcx>,
+        cx: &CodegenCx<'ll, 'tcx>,
         sig: ty::FnSig<'tcx>,
         extra_args: &[Ty<'tcx>],
         mk_arg_type: impl Fn(Ty<'tcx>, Option<usize>) -> ArgType<'tcx, Ty<'tcx>>,
@@ -497,7 +498,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
     }
 
     fn adjust_for_abi(&mut self,
-                      cx: &CodegenCx<'a, 'tcx>,
+                      cx: &CodegenCx<'ll, 'tcx>,
                       abi: Abi) {
         if abi == Abi::Unadjusted { return }
 
@@ -564,7 +565,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
         }
     }
 
-    fn llvm_type(&self, cx: &CodegenCx<'a, 'tcx>) -> Type {
+    fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type {
         let args_capacity: usize = self.args.iter().map(|arg|
             if arg.pad.is_some() { 1 } else { 0 } +
             if let PassMode::Pair(_, _) = arg.mode { 2 } else { 1 }
@@ -606,9 +607,9 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
         }
 
         if self.variadic {
-            Type::variadic_func(&llargument_tys, &llreturn_ty)
+            Type::variadic_func(&llargument_tys, llreturn_ty)
         } else {
-            Type::func(&llargument_tys, &llreturn_ty)
+            Type::func(&llargument_tys, llreturn_ty)
         }
     }
 
@@ -629,7 +630,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
         }
     }
 
-    fn apply_attrs_llfn(&self, llfn: ValueRef) {
+    fn apply_attrs_llfn(&self, llfn: &'ll Value) {
         let mut i = 0;
         let mut apply = |attrs: &ArgAttributes| {
             attrs.apply_llfn(llvm::AttributePlace::Argument(i), llfn);
@@ -659,7 +660,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
         }
     }
 
-    fn apply_attrs_callsite(&self, bx: &Builder<'a, 'tcx>, callsite: ValueRef) {
+    fn apply_attrs_callsite(&self, bx: &Builder<'a, 'll, 'tcx>, callsite: &'ll Value) {
         let mut i = 0;
         let mut apply = |attrs: &ArgAttributes| {
             attrs.apply_callsite(llvm::AttributePlace::Argument(i), callsite);

src/librustc_codegen_llvm/allocator.rs

@@ -9,7 +9,6 @@
 // except according to those terms.
 
 use std::ffi::CString;
-use std::ptr;
 
 use attributes;
 use libc::c_uint;
@@ -21,8 +20,8 @@ use ModuleLlvm;
 use llvm::{self, False, True};
 
 pub(crate) unsafe fn codegen(tcx: TyCtxt, mods: &ModuleLlvm, kind: AllocatorKind) {
-    let llcx = mods.llcx;
-    let llmod = mods.llmod;
+    let llcx = &*mods.llcx;
+    let llmod = mods.llmod();
     let usize = match &tcx.sess.target.target.target_pointer_width[..] {
         "16" => llvm::LLVMInt16TypeInContext(llcx),
         "32" => llvm::LLVMInt32TypeInContext(llcx),
@@ -90,7 +89,7 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt, mods: &ModuleLlvm, kind: AllocatorKind
                                           callee,
                                           args.as_ptr(),
                                           args.len() as c_uint,
-                                          ptr::null_mut(),
+                                          None,
                                           "\0".as_ptr() as *const _);
         llvm::LLVMSetTailCall(ret, True);
         if output.is_some() {

src/librustc_codegen_llvm/asm.rs

@@ -8,11 +8,12 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use llvm::{self, ValueRef};
+use llvm;
 use common::*;
 use type_::Type;
 use type_of::LayoutLlvmExt;
 use builder::Builder;
+use value::Value;
 
 use rustc::hir;
 
@@ -24,11 +25,11 @@ use syntax::ast::AsmDialect;
 use libc::{c_uint, c_char};
 
 // Take an inline assembly expression and splat it out via LLVM
-pub fn codegen_inline_asm<'a, 'tcx>(
-    bx: &Builder<'a, 'tcx>,
+pub fn codegen_inline_asm(
+    bx: &Builder<'a, 'll, 'tcx>,
     ia: &hir::InlineAsm,
-    outputs: Vec<PlaceRef<'tcx>>,
-    mut inputs: Vec<ValueRef>
+    outputs: Vec<PlaceRef<'ll, 'tcx>>,
+    mut inputs: Vec<&'ll Value>
 ) {
     let mut ext_constraints = vec![];
     let mut output_types = vec![];
@@ -111,7 +112,7 @@ pub fn codegen_inline_asm<'a, 'tcx>(
         let kind = llvm::LLVMGetMDKindIDInContext(bx.cx.llcx,
             key.as_ptr() as *const c_char, key.len() as c_uint);
 
-        let val: llvm::ValueRef = C_i32(bx.cx, ia.ctxt.outer().as_u32() as i32);
+        let val: &'ll Value = C_i32(bx.cx, ia.ctxt.outer().as_u32() as i32);
 
         llvm::LLVMSetMetadata(r, kind,
             llvm::LLVMMDNodeInContext(bx.cx.llcx, &val, 1));

src/librustc_codegen_llvm/attributes.rs

@@ -22,15 +22,17 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_target::spec::PanicStrategy;
 
 use attributes;
-use llvm::{self, Attribute, ValueRef};
+use llvm::{self, Attribute};
 use llvm::AttributePlace::Function;
 use llvm_util;
 pub use syntax::attr::{self, InlineAttr};
+
 use context::CodegenCx;
+use value::Value;
 
 /// Mark LLVM function to use provided inline heuristic.
 #[inline]
-pub fn inline(val: ValueRef, inline: InlineAttr) {
+pub fn inline(val: &'ll Value, inline: InlineAttr) {
     use self::InlineAttr::*;
     match inline {
         Hint   => Attribute::InlineHint.apply_llfn(Function, val),
@@ -46,38 +48,38 @@ pub fn inline(val: ValueRef, inline: InlineAttr) {
 
 /// Tell LLVM to emit or not emit the information necessary to unwind the stack for the function.
 #[inline]
-pub fn emit_uwtable(val: ValueRef, emit: bool) {
+pub fn emit_uwtable(val: &'ll Value, emit: bool) {
     Attribute::UWTable.toggle_llfn(Function, val, emit);
 }
 
 /// Tell LLVM whether the function can or cannot unwind.
 #[inline]
-pub fn unwind(val: ValueRef, can_unwind: bool) {
+pub fn unwind(val: &'ll Value, can_unwind: bool) {
     Attribute::NoUnwind.toggle_llfn(Function, val, !can_unwind);
 }
 
 /// Tell LLVM whether it should optimize function for size.
 #[inline]
 #[allow(dead_code)] // possibly useful function
-pub fn set_optimize_for_size(val: ValueRef, optimize: bool) {
+pub fn set_optimize_for_size(val: &'ll Value, optimize: bool) {
     Attribute::OptimizeForSize.toggle_llfn(Function, val, optimize);
 }
 
 /// Tell LLVM if this function should be 'naked', i.e. skip the epilogue and prologue.
 #[inline]
-pub fn naked(val: ValueRef, is_naked: bool) {
+pub fn naked(val: &'ll Value, is_naked: bool) {
     Attribute::Naked.toggle_llfn(Function, val, is_naked);
 }
 
-pub fn set_frame_pointer_elimination(cx: &CodegenCx, llfn: ValueRef) {
+pub fn set_frame_pointer_elimination(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
     if cx.sess().must_not_eliminate_frame_pointers() {
         llvm::AddFunctionAttrStringValue(
             llfn, llvm::AttributePlace::Function,
             cstr("no-frame-pointer-elim\0"), cstr("true\0"));
     }
 }
 
-pub fn set_probestack(cx: &CodegenCx, llfn: ValueRef) {
+pub fn set_probestack(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
     // Only use stack probes if the target specification indicates that we
     // should be using stack probes
     if !cx.sess().target.target.options.stack_probes {
@@ -123,7 +125,7 @@ pub fn llvm_target_features(sess: &Session) -> impl Iterator<Item = &str> {
 
 /// Composite function which sets LLVM attributes for function depending on its AST (#[attribute])
 /// attributes.
-pub fn from_fn_attrs(cx: &CodegenCx, llfn: ValueRef, id: DefId) {
+pub fn from_fn_attrs(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value, id: DefId) {
     let codegen_fn_attrs = cx.tcx.codegen_fn_attrs(id);
 
     inline(llfn, codegen_fn_attrs.inline);