Rename `adjustment::PointerCast` and variants using it to `PointerCoercion`

It makes it sound like the `ExprKind` and `Rvalue` are supposed to represent all pointer related
casts, when in reality their just used to share a some enum variants. Make it clear there these
are only coercion to make it clear why only some pointer related "casts" are in the enum.

1 files changed, 13 insertions, 9 deletions

diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
index ab9eb421c5a..956f03d2578 100644
--- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
@@ -11,7 +11,7 @@ use rustc_middle::mir;
 use rustc_middle::mir::Operand;
 use rustc_middle::ty::cast::{CastTy, IntTy};
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout};
-use rustc_middle::ty::{self, adjustment::PointerCast, Instance, Ty, TyCtxt};
+use rustc_middle::ty::{self, adjustment::PointerCoercion, Instance, Ty, TyCtxt};
 use rustc_session::config::OptLevel;
 use rustc_span::source_map::{Span, DUMMY_SP};
 use rustc_target::abi::{self, FIRST_VARIANT};
@@ -32,7 +32,11 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 cg_operand.val.store(bx, dest);
             }
 
-            mir::Rvalue::Cast(mir::CastKind::Pointer(PointerCast::Unsize), ref source, _) => {
+            mir::Rvalue::Cast(
+                mir::CastKind::PointerCoercion(PointerCoercion::Unsize),
+                ref source,
+                _,
+            ) => {
                 // The destination necessarily contains a fat pointer, so if
                 // it's a scalar pair, it's a fat pointer or newtype thereof.
                 if bx.cx().is_backend_scalar_pair(dest.layout) {
@@ -411,7 +415,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         let lladdr = bx.ptrtoint(llptr, llcast_ty);
                         OperandValue::Immediate(lladdr)
                     }
-                    mir::CastKind::Pointer(PointerCast::ReifyFnPointer) => {
+                    mir::CastKind::PointerCoercion(PointerCoercion::ReifyFnPointer) => {
                         match *operand.layout.ty.kind() {
                             ty::FnDef(def_id, substs) => {
                                 let instance = ty::Instance::resolve_for_fn_ptr(
@@ -427,7 +431,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             _ => bug!("{} cannot be reified to a fn ptr", operand.layout.ty),
                         }
                     }
-                    mir::CastKind::Pointer(PointerCast::ClosureFnPointer(_)) => {
+                    mir::CastKind::PointerCoercion(PointerCoercion::ClosureFnPointer(_)) => {
                         match *operand.layout.ty.kind() {
                             ty::Closure(def_id, substs) => {
                                 let instance = Instance::resolve_closure(
@@ -443,11 +447,11 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             _ => bug!("{} cannot be cast to a fn ptr", operand.layout.ty),
                         }
                     }
-                    mir::CastKind::Pointer(PointerCast::UnsafeFnPointer) => {
+                    mir::CastKind::PointerCoercion(PointerCoercion::UnsafeFnPointer) => {
                         // This is a no-op at the LLVM level.
                         operand.val
                     }
-                    mir::CastKind::Pointer(PointerCast::Unsize) => {
+                    mir::CastKind::PointerCoercion(PointerCoercion::Unsize) => {
                         assert!(bx.cx().is_backend_scalar_pair(cast));
                         let (lldata, llextra) = match operand.val {
                             OperandValue::Pair(lldata, llextra) => {
@@ -470,7 +474,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             base::unsize_ptr(bx, lldata, operand.layout.ty, cast.ty, llextra);
                         OperandValue::Pair(lldata, llextra)
                     }
-                    mir::CastKind::Pointer(PointerCast::MutToConstPointer)
+                    mir::CastKind::PointerCoercion(PointerCoercion::MutToConstPointer)
                     | mir::CastKind::PtrToPtr
                         if bx.cx().is_backend_scalar_pair(operand.layout) =>
                     {
@@ -504,8 +508,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             base::cast_to_dyn_star(bx, lldata, operand.layout, cast.ty, llextra);
                         OperandValue::Pair(lldata, llextra)
                     }
-                    mir::CastKind::Pointer(
-                        PointerCast::MutToConstPointer | PointerCast::ArrayToPointer,
+                    mir::CastKind::PointerCoercion(
+                        PointerCoercion::MutToConstPointer | PointerCoercion::ArrayToPointer,
                     )
                     | mir::CastKind::IntToInt
                     | mir::CastKind::FloatToInt