Auto merge of rust-lang#92816 - tmiasko:rm-llvm-asm, r=Amanieu

Remove deprecated LLVM-style inline assembly

The `llvm_asm!` was deprecated back in rust-lang#87590 1.56.0, with intention to remove
it once `asm!` was stabilized, which already happened in rust-lang#91728 1.59.0. Now it
is time to remove `llvm_asm!` to avoid continued maintenance cost.

Closes rust-lang#70173.
Closes rust-lang#92794.
Closes rust-lang#87612.
Closes rust-lang#82065.

cc `@rust-lang/wg-inline-asm`

r? `@Amanieu`

Author: bors

Diff for: compiler/rustc_ast/src/ast.rs

@@ -1266,7 +1266,7 @@ impl Expr {
             ExprKind::Break(..) => ExprPrecedence::Break,
             ExprKind::Continue(..) => ExprPrecedence::Continue,
             ExprKind::Ret(..) => ExprPrecedence::Ret,
-            ExprKind::InlineAsm(..) | ExprKind::LlvmInlineAsm(..) => ExprPrecedence::InlineAsm,
+            ExprKind::InlineAsm(..) => ExprPrecedence::InlineAsm,
             ExprKind::MacCall(..) => ExprPrecedence::Mac,
             ExprKind::Struct(..) => ExprPrecedence::Struct,
             ExprKind::Repeat(..) => ExprPrecedence::Repeat,
@@ -1423,8 +1423,6 @@ pub enum ExprKind {
 
     /// Output of the `asm!()` macro.
     InlineAsm(P<InlineAsm>),
-    /// Output of the `llvm_asm!()` macro.
-    LlvmInlineAsm(P<LlvmInlineAsm>),
 
     /// A macro invocation; pre-expansion.
     MacCall(MacCall),
@@ -2076,41 +2074,6 @@ pub struct InlineAsm {
     pub line_spans: Vec<Span>,
 }
 
-/// Inline assembly dialect.
-///
-/// E.g., `"intel"` as in `llvm_asm!("mov eax, 2" : "={eax}"(result) : : : "intel")`.
-#[derive(Clone, PartialEq, Encodable, Decodable, Debug, Copy, Hash, HashStable_Generic)]
-pub enum LlvmAsmDialect {
-    Att,
-    Intel,
-}
-
-/// LLVM-style inline assembly.
-///
-/// E.g., `"={eax}"(result)` as in `llvm_asm!("mov eax, 2" : "={eax}"(result) : : : "intel")`.
-#[derive(Clone, Encodable, Decodable, Debug)]
-pub struct LlvmInlineAsmOutput {
-    pub constraint: Symbol,
-    pub expr: P<Expr>,
-    pub is_rw: bool,
-    pub is_indirect: bool,
-}
-
-/// LLVM-style inline assembly.
-///
-/// E.g., `llvm_asm!("NOP");`.
-#[derive(Clone, Encodable, Decodable, Debug)]
-pub struct LlvmInlineAsm {
-    pub asm: Symbol,
-    pub asm_str_style: StrStyle,
-    pub outputs: Vec<LlvmInlineAsmOutput>,
-    pub inputs: Vec<(Symbol, P<Expr>)>,
-    pub clobbers: Vec<Symbol>,
-    pub volatile: bool,
-    pub alignstack: bool,
-    pub dialect: LlvmAsmDialect,
-}
-
 /// A parameter in a function header.
 ///
 /// E.g., `bar: usize` as in `fn foo(bar: usize)`.

Diff for: compiler/rustc_ast/src/mut_visit.rs

@@ -1350,23 +1350,6 @@ pub fn noop_visit_expr<T: MutVisitor>(
             visit_opt(expr, |expr| vis.visit_expr(expr));
         }
         ExprKind::InlineAsm(asm) => noop_visit_inline_asm(asm, vis),
-        ExprKind::LlvmInlineAsm(asm) => {
-            let LlvmInlineAsm {
-                asm: _,
-                asm_str_style: _,
-                outputs,
-                inputs,
-                clobbers: _,
-                volatile: _,
-                alignstack: _,
-                dialect: _,
-            } = asm.deref_mut();
-            for out in outputs {
-                let LlvmInlineAsmOutput { constraint: _, expr, is_rw: _, is_indirect: _ } = out;
-                vis.visit_expr(expr);
-            }
-            visit_vec(inputs, |(_c, expr)| vis.visit_expr(expr));
-        }
         ExprKind::MacCall(mac) => vis.visit_mac_call(mac),
         ExprKind::Struct(se) => {
             let StructExpr { qself, path, fields, rest } = se.deref_mut();

Diff for: compiler/rustc_ast/src/visit.rs

@@ -864,14 +864,6 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
         ExprKind::MacCall(ref mac) => visitor.visit_mac_call(mac),
         ExprKind::Paren(ref subexpression) => visitor.visit_expr(subexpression),
         ExprKind::InlineAsm(ref asm) => walk_inline_asm(visitor, asm),
-        ExprKind::LlvmInlineAsm(ref ia) => {
-            for &(_, ref input) in &ia.inputs {
-                visitor.visit_expr(input)
-            }
-            for output in &ia.outputs {
-                visitor.visit_expr(&output.expr)
-            }
-        }
         ExprKind::Yield(ref optional_expression) => {
             walk_list!(visitor, visit_expr, optional_expression);
         }

Diff for: compiler/rustc_ast_lowering/src/expr.rs

@@ -226,7 +226,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 ExprKind::InlineAsm(ref asm) => {
                     hir::ExprKind::InlineAsm(self.lower_inline_asm(e.span, asm))
                 }
-                ExprKind::LlvmInlineAsm(ref asm) => self.lower_expr_llvm_asm(asm),
                 ExprKind::Struct(ref se) => {
                     let rest = match &se.rest {
                         StructRest::Base(e) => Some(self.lower_expr(e)),
@@ -1286,38 +1285,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
         result
     }
 
-    fn lower_expr_llvm_asm(&mut self, asm: &LlvmInlineAsm) -> hir::ExprKind<'hir> {
-        let inner = hir::LlvmInlineAsmInner {
-            inputs: asm.inputs.iter().map(|&(c, _)| c).collect(),
-            outputs: asm
-                .outputs
-                .iter()
-                .map(|out| hir::LlvmInlineAsmOutput {
-                    constraint: out.constraint,
-                    is_rw: out.is_rw,
-                    is_indirect: out.is_indirect,
-                    span: self.lower_span(out.expr.span),
-                })
-                .collect(),
-            asm: asm.asm,
-            asm_str_style: asm.asm_str_style,
-            clobbers: asm.clobbers.clone(),
-            volatile: asm.volatile,
-            alignstack: asm.alignstack,
-            dialect: asm.dialect,
-        };
-        let hir_asm = hir::LlvmInlineAsm {
-            inner,
-            inputs_exprs: self.arena.alloc_from_iter(
-                asm.inputs.iter().map(|&(_, ref input)| self.lower_expr_mut(input)),
-            ),
-            outputs_exprs: self
-                .arena
-                .alloc_from_iter(asm.outputs.iter().map(|out| self.lower_expr_mut(&out.expr))),
-        };
-        hir::ExprKind::LlvmInlineAsm(self.arena.alloc(hir_asm))
-    }
-
     fn lower_expr_field(&mut self, f: &ExprField) -> hir::ExprField<'hir> {
         hir::ExprField {
             hir_id: self.next_id(),

Diff for: compiler/rustc_ast_passes/src/ast_validation.rs

@@ -960,15 +960,6 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 return;
             }
             ExprKind::Let(..) if !let_allowed => this.ban_let_expr(expr),
-            ExprKind::LlvmInlineAsm(..) if !this.session.target.allow_asm => {
-                struct_span_err!(
-                    this.session,
-                    expr.span,
-                    E0472,
-                    "llvm_asm! is unsupported on this target"
-                )
-                .emit();
-            }
             ExprKind::Match(expr, arms) => {
                 this.visit_expr(expr);
                 for arm in arms {

Diff for: compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -2168,62 +2168,6 @@ impl<'a> State<'a> {
                 self.word("asm!");
                 self.print_inline_asm(a);
             }
-            ast::ExprKind::LlvmInlineAsm(ref a) => {
-                self.word("llvm_asm!");
-                self.popen();
-                self.print_symbol(a.asm, a.asm_str_style);
-                self.word_space(":");
-
-                self.commasep(Inconsistent, &a.outputs, |s, out| {
-                    let constraint = out.constraint.as_str();
-                    let mut ch = constraint.chars();
-                    match ch.next() {
-                        Some('=') if out.is_rw => {
-                            s.print_string(&format!("+{}", ch.as_str()), ast::StrStyle::Cooked)
-                        }
-                        _ => s.print_string(&constraint, ast::StrStyle::Cooked),
-                    }
-                    s.popen();
-                    s.print_expr(&out.expr);
-                    s.pclose();
-                });
-                self.space();
-                self.word_space(":");
-
-                self.commasep(Inconsistent, &a.inputs, |s, &(co, ref o)| {
-                    s.print_symbol(co, ast::StrStyle::Cooked);
-                    s.popen();
-                    s.print_expr(o);
-                    s.pclose();
-                });
-                self.space();
-                self.word_space(":");
-
-                self.commasep(Inconsistent, &a.clobbers, |s, &co| {
-                    s.print_symbol(co, ast::StrStyle::Cooked);
-                });
-
-                let mut options = vec![];
-                if a.volatile {
-                    options.push("volatile");
-                }
-                if a.alignstack {
-                    options.push("alignstack");
-                }
-                if a.dialect == ast::LlvmAsmDialect::Intel {
-                    options.push("intel");
-                }
-
-                if !options.is_empty() {
-                    self.space();
-                    self.word_space(":");
-                    self.commasep(Inconsistent, &options, |s, &co| {
-                        s.print_string(co, ast::StrStyle::Cooked);
-                    });
-                }
-
-                self.pclose();
-            }
             ast::ExprKind::MacCall(ref m) => self.print_mac(m),
             ast::ExprKind::Paren(ref e) => {
                 self.popen();

Diff for: compiler/rustc_borrowck/src/dataflow.rs

@@ -8,7 +8,6 @@ use rustc_mir_dataflow::ResultsVisitable;
 use rustc_mir_dataflow::{self, fmt::DebugWithContext, CallReturnPlaces, GenKill};
 use rustc_mir_dataflow::{Analysis, Direction, Results};
 use std::fmt;
-use std::iter;
 
 use crate::{
     places_conflict, BorrowSet, PlaceConflictBias, PlaceExt, RegionInferenceContext, ToRegionVid,
@@ -385,14 +384,6 @@ impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
                 self.kill_borrows_on_place(trans, Place::from(local));
             }
 
-            mir::StatementKind::LlvmInlineAsm(ref asm) => {
-                for (output, kind) in iter::zip(&*asm.outputs, &asm.asm.outputs) {
-                    if !kind.is_indirect && !kind.is_rw {
-                        self.kill_borrows_on_place(trans, *output);
-                    }
-                }
-            }
-
             mir::StatementKind::FakeRead(..)
             | mir::StatementKind::SetDiscriminant { .. }
             | mir::StatementKind::StorageLive(..)

Diff for: compiler/rustc_borrowck/src/def_use.rs

@@ -16,9 +16,6 @@ pub fn categorize(context: PlaceContext) -> Option<DefUse> {
 
         PlaceContext::MutatingUse(MutatingUseContext::Store) |
 
-        // This is potentially both a def and a use...
-        PlaceContext::MutatingUse(MutatingUseContext::LlvmAsmOutput) |
-
         // We let Call define the result in both the success and
         // unwind cases. This is not really correct, however it
         // does not seem to be observable due to the way that we

Diff for: compiler/rustc_borrowck/src/invalidation.rs

@@ -5,12 +5,11 @@ use rustc_middle::mir::{BorrowKind, Mutability, Operand};
 use rustc_middle::mir::{InlineAsmOperand, Terminator, TerminatorKind};
 use rustc_middle::mir::{Statement, StatementKind};
 use rustc_middle::ty::TyCtxt;
-use std::iter;
 
 use crate::{
     borrow_set::BorrowSet, facts::AllFacts, location::LocationTable, path_utils::*, AccessDepth,
-    Activation, ArtificialField, BorrowIndex, Deep, JustWrite, LocalMutationIsAllowed, MutateMode,
-    Read, ReadKind, ReadOrWrite, Reservation, Shallow, Write, WriteAndRead, WriteKind,
+    Activation, ArtificialField, BorrowIndex, Deep, LocalMutationIsAllowed, Read, ReadKind,
+    ReadOrWrite, Reservation, Shallow, Write, WriteKind,
 };
 
 pub(super) fn generate_invalidates<'tcx>(
@@ -59,37 +58,13 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
             StatementKind::Assign(box (lhs, rhs)) => {
                 self.consume_rvalue(location, rhs);
 
-                self.mutate_place(location, *lhs, Shallow(None), JustWrite);
+                self.mutate_place(location, *lhs, Shallow(None));
             }
             StatementKind::FakeRead(box (_, _)) => {
                 // Only relevant for initialized/liveness/safety checks.
             }
             StatementKind::SetDiscriminant { place, variant_index: _ } => {
-                self.mutate_place(location, **place, Shallow(None), JustWrite);
-            }
-            StatementKind::LlvmInlineAsm(asm) => {
-                for (o, output) in iter::zip(&asm.asm.outputs, &*asm.outputs) {
-                    if o.is_indirect {
-                        // FIXME(eddyb) indirect inline asm outputs should
-                        // be encoded through MIR place derefs instead.
-                        self.access_place(
-                            location,
-                            *output,
-                            (Deep, Read(ReadKind::Copy)),
-                            LocalMutationIsAllowed::No,
-                        );
-                    } else {
-                        self.mutate_place(
-                            location,
-                            *output,
-                            if o.is_rw { Deep } else { Shallow(None) },
-                            if o.is_rw { WriteAndRead } else { JustWrite },
-                        );
-                    }
-                }
-                for (_, input) in asm.inputs.iter() {
-                    self.consume_operand(location, input);
-                }
+                self.mutate_place(location, **place, Shallow(None));
             }
             StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
                 ref src,
@@ -142,7 +117,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
                 target: _,
                 unwind: _,
             } => {
-                self.mutate_place(location, *drop_place, Deep, JustWrite);
+                self.mutate_place(location, *drop_place, Deep);
                 self.consume_operand(location, new_value);
             }
             TerminatorKind::Call {
@@ -158,7 +133,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
                     self.consume_operand(location, arg);
                 }
                 if let Some((dest, _ /*bb*/)) = destination {
-                    self.mutate_place(location, *dest, Deep, JustWrite);
+                    self.mutate_place(location, *dest, Deep);
                 }
             }
             TerminatorKind::Assert { ref cond, expected: _, ref msg, target: _, cleanup: _ } => {
@@ -181,7 +156,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
                     }
                 }
 
-                self.mutate_place(location, *resume_arg, Deep, JustWrite);
+                self.mutate_place(location, *resume_arg, Deep);
             }
             TerminatorKind::Resume | TerminatorKind::Return | TerminatorKind::GeneratorDrop => {
                 // Invalidate all borrows of local places
@@ -208,13 +183,13 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
                         }
                         InlineAsmOperand::Out { reg: _, late: _, place, .. } => {
                             if let Some(place) = place {
-                                self.mutate_place(location, place, Shallow(None), JustWrite);
+                                self.mutate_place(location, place, Shallow(None));
                             }
                         }
                         InlineAsmOperand::InOut { reg: _, late: _, ref in_value, out_place } => {
                             self.consume_operand(location, in_value);
                             if let Some(out_place) = out_place {
-                                self.mutate_place(location, out_place, Shallow(None), JustWrite);
+                                self.mutate_place(location, out_place, Shallow(None));
                             }
                         }
                         InlineAsmOperand::Const { value: _ }
@@ -238,13 +213,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
 
 impl<'cx, 'tcx> InvalidationGenerator<'cx, 'tcx> {
     /// Simulates mutation of a place.
-    fn mutate_place(
-        &mut self,
-        location: Location,
-        place: Place<'tcx>,
-        kind: AccessDepth,
-        _mode: MutateMode,
-    ) {
+    fn mutate_place(&mut self, location: Location, place: Place<'tcx>, kind: AccessDepth) {
         self.access_place(
             location,
             place,