Rollup merge of #128570 - folkertdev:stabilize-asm-const, r=Amanieu

Stabilize `asm_const`

tracking issue: #93332

reference PR: rust-lang/reference#1556

this will probably require some CI wrangling (and a rebase), so let's get that over with even though the final required PR is not merged yet.

r? `@ghost`

Author: jieyouxu

compiler/rustc_ast_lowering/messages.ftl

@@ -175,8 +175,6 @@ ast_lowering_underscore_expr_lhs_assign =
     .label = `_` not allowed here
 
 ast_lowering_unstable_inline_assembly = inline assembly is not stable yet on this architecture
-ast_lowering_unstable_inline_assembly_const_operands =
-    const operands for inline assembly are unstable
 ast_lowering_unstable_inline_assembly_label_operands =
     label operands for inline assembly are unstable
 ast_lowering_unstable_may_unwind = the `may_unwind` option is unstable

compiler/rustc_ast_lowering/src/asm.rs

@@ -183,20 +183,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                             out_expr: out_expr.as_ref().map(|expr| self.lower_expr(expr)),
                         }
                     }
-                    InlineAsmOperand::Const { anon_const } => {
-                        if !self.tcx.features().asm_const {
-                            feature_err(
-                                sess,
-                                sym::asm_const,
-                                *op_sp,
-                                fluent::ast_lowering_unstable_inline_assembly_const_operands,
-                            )
-                            .emit();
-                        }
-                        hir::InlineAsmOperand::Const {
-                            anon_const: self.lower_anon_const_to_anon_const(anon_const),
-                        }
-                    }
+                    InlineAsmOperand::Const { anon_const } => hir::InlineAsmOperand::Const {
+                        anon_const: self.lower_anon_const_to_anon_const(anon_const),
+                    },
                     InlineAsmOperand::Sym { sym } => {
                         let static_def_id = self
                             .resolver

compiler/rustc_codegen_gcc/tests/run/asm.rs

@@ -3,12 +3,10 @@
 // Run-time:
 //   status: 0
 
-#![feature(asm_const)]
-
-#[cfg(target_arch="x86_64")]
+#[cfg(target_arch = "x86_64")]
 use std::arch::{asm, global_asm};
 
-#[cfg(target_arch="x86_64")]
+#[cfg(target_arch = "x86_64")]
 global_asm!(
     "
     .global add_asm
@@ -22,7 +20,7 @@ extern "C" {
     fn add_asm(a: i64, b: i64) -> i64;
 }
 
-#[cfg(target_arch="x86_64")]
+#[cfg(target_arch = "x86_64")]
 pub unsafe fn mem_cpy(dst: *mut u8, src: *const u8, len: usize) {
     asm!(
         "rep movsb",
@@ -33,7 +31,7 @@ pub unsafe fn mem_cpy(dst: *mut u8, src: *const u8, len: usize) {
     );
 }
 
-#[cfg(target_arch="x86_64")]
+#[cfg(target_arch = "x86_64")]
 fn asm() {
     unsafe {
         asm!("nop");
@@ -178,9 +176,8 @@ fn asm() {
     assert_eq!(array1, array2);
 }
 
-#[cfg(not(target_arch="x86_64"))]
-fn asm() {
-}
+#[cfg(not(target_arch = "x86_64"))]
+fn asm() {}
 
 fn main() {
     asm();

compiler/rustc_feature/src/accepted.rs

@@ -60,6 +60,8 @@ declare_features! (
     (accepted, adx_target_feature, "1.61.0", Some(44839)),
     /// Allows explicit discriminants on non-unit enum variants.
     (accepted, arbitrary_enum_discriminant, "1.66.0", Some(60553)),
+    /// Allows using `const` operands in inline assembly.
+    (accepted, asm_const, "CURRENT_RUSTC_VERSION", Some(93332)),
     /// Allows using `sym` operands in inline assembly.
     (accepted, asm_sym, "1.66.0", Some(93333)),
     /// Allows the definition of associated constants in `trait` or `impl` blocks.

compiler/rustc_feature/src/unstable.rs

@@ -348,8 +348,6 @@ declare_features! (
     (unstable, alloc_error_handler, "1.29.0", Some(51540)),
     /// Allows trait methods with arbitrary self types.
     (unstable, arbitrary_self_types, "1.23.0", Some(44874)),
-    /// Allows using `const` operands in inline assembly.
-    (unstable, asm_const, "1.58.0", Some(93332)),
     /// Enables experimental inline assembly support for additional architectures.
     (unstable, asm_experimental_arch, "1.58.0", Some(93335)),
     /// Allows using `label` operands in inline assembly.

library/core/src/lib.rs

@@ -193,12 +193,12 @@
 //
 // Language features:
 // tidy-alphabetical-start
+#![cfg_attr(bootstrap, feature(asm_const))]
 #![cfg_attr(bootstrap, feature(min_exhaustive_patterns))]
 #![feature(abi_unadjusted)]
 #![feature(adt_const_params)]
 #![feature(allow_internal_unsafe)]
 #![feature(allow_internal_unstable)]
-#![feature(asm_const)]
 #![feature(auto_traits)]
 #![feature(cfg_sanitize)]
 #![feature(cfg_target_has_atomic)]

src/doc/unstable-book/src/language-features/asm-const.md

@@ -4,7 +4,6 @@
 //@ compile-flags: -C llvm-args=--x86-asm-syntax=intel
 //@ compile-flags: -C symbol-mangling-version=v0
 
-#![feature(asm_const)]
 #![crate_type = "rlib"]
 
 use std::arch::global_asm;

tests/assembly/asm/global_asm.rs

@@ -2,7 +2,7 @@
 //@ compile-flags: --target msp430-none-elf
 //@ needs-llvm-components: msp430
 
-#![feature(no_core, lang_items, rustc_attrs, asm_experimental_arch, asm_const)]
+#![feature(no_core, lang_items, rustc_attrs, asm_experimental_arch)]
 #![crate_type = "rlib"]
 #![no_core]
 #![allow(non_camel_case_types)]

tests/assembly/asm/msp430-types.rs

@@ -1,8 +1,6 @@
 //@ only-aarch64
 //@ compile-flags: -C target-feature=+neon
 
-#![feature(asm_const)]
-
 use std::arch::asm;
 
 fn main() {