Auto merge of #88208 - petrochenkov:lowspan, r=Aaron1011

ast_lowering: Introduce `lower_span` for catching all spans entering HIR

This PR cherry-picks the `fn lower_span` change from #84373.
I also introduced `fn lower_ident` for lowering spans in identifiers, and audited places where HIR structures with spans or identifiers are constructed and added a few missing `lower_span`s/`lower_ident`s.

Having a hook for spans entering HIR can be useful for things other than #84373, e.g. #35148.
I also want to check whether this change causes perf regressions due to some accidental inlining issues.

r? `@cjgillot`

compiler/rustc_ast_lowering/src/asm.rs

@@ -128,7 +128,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         hir::InlineAsmOperand::Sym { expr: self.lower_expr_mut(expr) }
                     }
                 };
-                (op, *op_sp)
+                (op, self.lower_span(*op_sp))
             })
             .collect();
 
@@ -384,16 +384,21 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                             late: true,
                             expr: None,
                         },
-                        abi_span,
+                        self.lower_span(abi_span),
                     ));
                 }
             }
         }
 
         let operands = self.arena.alloc_from_iter(operands);
         let template = self.arena.alloc_from_iter(asm.template.iter().cloned());
-        let template_strs = self.arena.alloc_from_iter(asm.template_strs.iter().cloned());
-        let line_spans = self.arena.alloc_slice(&asm.line_spans[..]);
+        let template_strs = self.arena.alloc_from_iter(
+            asm.template_strs
+                .iter()
+                .map(|(sym, snippet, span)| (*sym, *snippet, self.lower_span(*span))),
+        );
+        let line_spans =
+            self.arena.alloc_from_iter(asm.line_spans.iter().map(|span| self.lower_span(*span)));
         let hir_asm =
             hir::InlineAsm { template, template_strs, operands, options: asm.options, line_spans };
         self.arena.alloc(hir_asm)