diff options
| -rw-r--r-- | compiler/rustc_builtin_macros/src/deriving/debug.rs | 205 | ||||
| -rw-r--r-- | compiler/rustc_expand/src/build.rs | 21 | ||||
| -rw-r--r-- | compiler/rustc_span/src/symbol.rs | 2 | ||||
| -rw-r--r-- | library/core/src/fmt/mod.rs | 228 |
4 files changed, 366 insertions, 90 deletions
diff --git a/compiler/rustc_builtin_macros/src/deriving/debug.rs b/compiler/rustc_builtin_macros/src/deriving/debug.rs index ecf70da6d96..1fffd6f9727 100644 --- a/compiler/rustc_builtin_macros/src/deriving/debug.rs +++ b/compiler/rustc_builtin_macros/src/deriving/debug.rs @@ -3,14 +3,10 @@ use crate::deriving::generic::*; use crate::deriving::path_std; use rustc_ast::ptr::P; -use rustc_ast::{self as ast, Expr, LocalKind, MetaItem}; +use rustc_ast::{self as ast, Expr, MetaItem}; use rustc_expand::base::{Annotatable, ExtCtxt}; -use rustc_span::symbol::{sym, Ident}; -use rustc_span::{Span, DUMMY_SP}; - -fn make_mut_borrow(cx: &mut ExtCtxt<'_>, sp: Span, expr: P<Expr>) -> P<Expr> { - cx.expr(sp, ast::ExprKind::AddrOf(ast::BorrowKind::Ref, ast::Mutability::Mut, expr)) -} +use rustc_span::symbol::{sym, Ident, Symbol}; +use rustc_span::Span; pub fn expand_deriving_debug( cx: &mut ExtCtxt<'_>, @@ -49,11 +45,7 @@ pub fn expand_deriving_debug( trait_def.expand(cx, mitem, item, push) } -/// We use the debug builders to do the heavy lifting here fn show_substructure(cx: &mut ExtCtxt<'_>, span: Span, substr: &Substructure<'_>) -> P<Expr> { - // build fmt.debug_struct(<name>).field(<fieldname>, &<fieldval>)....build() - // or fmt.debug_tuple(<name>).field(&<fieldval>)....build() - // based on the "shape". let (ident, vdata, fields) = match substr.fields { Struct(vdata, fields) => (substr.type_ident, *vdata, fields), EnumMatching(_, _, v, fields) => (v.ident, &v.data, fields), @@ -67,93 +59,130 @@ fn show_substructure(cx: &mut ExtCtxt<'_>, span: Span, substr: &Substructure<'_> let name = cx.expr_lit(span, ast::LitKind::Str(ident.name, ast::StrStyle::Cooked)); let fmt = substr.nonself_args[0].clone(); - // Special fast path for unit variants. In the common case of an enum that is entirely unit - // variants (i.e. a C-like enum), this fast path allows LLVM to eliminate the entire switch in - // favor of a lookup table. - if let ast::VariantData::Unit(..) = vdata { - let fn_path_write_str = cx.std_path(&[sym::fmt, sym::Formatter, sym::write_str]); - let expr = cx.expr_call_global(span, fn_path_write_str, vec![fmt, name]); - let stmts = vec![cx.stmt_expr(expr)]; - let block = cx.block(span, stmts); - return cx.expr_block(block); - } - - let builder = Ident::new(sym::debug_trait_builder, span); - let builder_expr = cx.expr_ident(span, builder); - - let mut stmts = Vec::with_capacity(fields.len() + 2); - let fn_path_finish; - match vdata { + // Struct and tuples are similar enough that we use the same code for both, + // with some extra pieces for structs due to the field names. + let (is_struct, args_per_field) = match vdata { ast::VariantData::Unit(..) => { - cx.span_bug(span, "unit variants should have been handled above"); + // Special fast path for unit variants. + //let fn_path_write_str = cx.std_path(&[sym::fmt, sym::Formatter, sym::write_str]); + //return cx.expr_call_global(span, fn_path_write_str, vec![fmt, name]); + assert!(fields.is_empty()); + (false, 0) } - ast::VariantData::Tuple(..) => { - // tuple struct/"normal" variant - let fn_path_debug_tuple = cx.std_path(&[sym::fmt, sym::Formatter, sym::debug_tuple]); - let expr = cx.expr_call_global(span, fn_path_debug_tuple, vec![fmt, name]); - let expr = make_mut_borrow(cx, span, expr); - stmts.push(cx.stmt_let(span, false, builder, expr)); - - for field in fields { - // Use double indirection to make sure this works for unsized types - let field = cx.expr_addr_of(field.span, field.self_.clone()); - let field = cx.expr_addr_of(field.span, field); - - let fn_path_field = cx.std_path(&[sym::fmt, sym::DebugTuple, sym::field]); - let expr = - cx.expr_call_global(span, fn_path_field, vec![builder_expr.clone(), field]); - - // Use `let _ = expr;` to avoid triggering the - // unused_results lint. - stmts.push(stmt_let_underscore(cx, span, expr)); - } + ast::VariantData::Tuple(..) => (false, 1), + ast::VariantData::Struct(..) => (true, 2), + }; - fn_path_finish = cx.std_path(&[sym::fmt, sym::DebugTuple, sym::finish]); - } - ast::VariantData::Struct(..) => { - // normal struct/struct variant - let fn_path_debug_struct = cx.std_path(&[sym::fmt, sym::Formatter, sym::debug_struct]); - let expr = cx.expr_call_global(span, fn_path_debug_struct, vec![fmt, name]); - let expr = make_mut_borrow(cx, span, expr); - stmts.push(cx.stmt_let(DUMMY_SP, false, builder, expr)); - - for field in fields { + // The number of fields that can be handled without an array. + const CUTOFF: usize = 5; + + if fields.is_empty() { + // Special case for no fields. + let fn_path_write_str = cx.std_path(&[sym::fmt, sym::Formatter, sym::write_str]); + cx.expr_call_global(span, fn_path_write_str, vec![fmt, name]) + } else if fields.len() <= CUTOFF { + // Few enough fields that we can use a specific-length method. + let debug = if is_struct { + format!("debug_struct_field{}_finish", fields.len()) + } else { + format!("debug_tuple_field{}_finish", fields.len()) + }; + let fn_path_debug = cx.std_path(&[sym::fmt, sym::Formatter, Symbol::intern(&debug)]); + + let mut args = Vec::with_capacity(2 + fields.len() * args_per_field); + args.extend([fmt, name]); + for i in 0..fields.len() { + let field = &fields[i]; + if is_struct { let name = cx.expr_lit( field.span, ast::LitKind::Str(field.name.unwrap().name, ast::StrStyle::Cooked), ); - - // Use double indirection to make sure this works for unsized types - let fn_path_field = cx.std_path(&[sym::fmt, sym::DebugStruct, sym::field]); - let field = cx.expr_addr_of(field.span, field.self_.clone()); - let field = cx.expr_addr_of(field.span, field); - let expr = cx.expr_call_global( - span, - fn_path_field, - vec![builder_expr.clone(), name, field], - ); - stmts.push(stmt_let_underscore(cx, span, expr)); + args.push(name); } - fn_path_finish = cx.std_path(&[sym::fmt, sym::DebugStruct, sym::finish]); + // Use double indirection to make sure this works for unsized types + let field = cx.expr_addr_of(field.span, field.self_.clone()); + let field = cx.expr_addr_of(field.span, field); + args.push(field); } - } + cx.expr_call_global(span, fn_path_debug, args) + } else { + // Enough fields that we must use the any-length method. + let mut name_exprs = Vec::with_capacity(fields.len()); + let mut value_exprs = Vec::with_capacity(fields.len()); + + for field in fields { + if is_struct { + name_exprs.push(cx.expr_lit( + field.span, + ast::LitKind::Str(field.name.unwrap().name, ast::StrStyle::Cooked), + )); + } - let expr = cx.expr_call_global(span, fn_path_finish, vec![builder_expr]); + // Use double indirection to make sure this works for unsized types + let value_ref = cx.expr_addr_of(field.span, field.self_.clone()); + value_exprs.push(cx.expr_addr_of(field.span, value_ref)); + } - stmts.push(cx.stmt_expr(expr)); - let block = cx.block(span, stmts); - cx.expr_block(block) -} + // `let names: &'static _ = &["field1", "field2"];` + let names_let = if is_struct { + let lt_static = Some(cx.lifetime_static(span)); + let ty_static_ref = + cx.ty_rptr(span, cx.ty_infer(span), lt_static, ast::Mutability::Not); + Some(cx.stmt_let_ty( + span, + false, + Ident::new(sym::names, span), + Some(ty_static_ref), + cx.expr_array_ref(span, name_exprs), + )) + } else { + None + }; + + // `let values: &[&dyn Debug] = &[&&self.field1, &&self.field2];` + let path_debug = cx.path_global(span, cx.std_path(&[sym::fmt, sym::Debug])); + let ty_dyn_debug = cx.ty( + span, + ast::TyKind::TraitObject(vec![cx.trait_bound(path_debug)], ast::TraitObjectSyntax::Dyn), + ); + let ty_slice = cx.ty( + span, + ast::TyKind::Slice(cx.ty_rptr(span, ty_dyn_debug, None, ast::Mutability::Not)), + ); + let values_let = cx.stmt_let_ty( + span, + false, + Ident::new(sym::values, span), + Some(cx.ty_rptr(span, ty_slice, None, ast::Mutability::Not)), + cx.expr_array_ref(span, value_exprs), + ); + + // `fmt::Formatter::debug_struct_fields_finish(fmt, name, names, values)` or + // `fmt::Formatter::debug_tuple_fields_finish(fmt, name, values)` + let sym_debug = if is_struct { + sym::debug_struct_fields_finish + } else { + sym::debug_tuple_fields_finish + }; + let fn_path_debug_internal = cx.std_path(&[sym::fmt, sym::Formatter, sym_debug]); + + let mut args = Vec::with_capacity(4); + args.push(fmt); + args.push(name); + if is_struct { + args.push(cx.expr_ident(span, Ident::new(sym::names, span))); + } + args.push(cx.expr_ident(span, Ident::new(sym::values, span))); + let expr = cx.expr_call_global(span, fn_path_debug_internal, args); -fn stmt_let_underscore(cx: &mut ExtCtxt<'_>, sp: Span, expr: P<ast::Expr>) -> ast::Stmt { - let local = P(ast::Local { - pat: cx.pat_wild(sp), - ty: None, - id: ast::DUMMY_NODE_ID, - kind: LocalKind::Init(expr), - span: sp, - attrs: ast::AttrVec::new(), - tokens: None, - }); - ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span: sp } + let mut stmts = Vec::with_capacity(3); + if is_struct { + stmts.push(names_let.unwrap()); + } + stmts.push(values_let); + stmts.push(cx.stmt_expr(expr)); + + cx.expr_block(cx.block(span, stmts)) + } } diff --git a/compiler/rustc_expand/src/build.rs b/compiler/rustc_expand/src/build.rs index 17dae915397..1694a8865dd 100644 --- a/compiler/rustc_expand/src/build.rs +++ b/compiler/rustc_expand/src/build.rs @@ -57,6 +57,10 @@ impl<'a> ExtCtxt<'a> { P(ast::Ty { id: ast::DUMMY_NODE_ID, span, kind, tokens: None }) } + pub fn ty_infer(&self, span: Span) -> P<ast::Ty> { + self.ty(span, ast::TyKind::Infer) + } + pub fn ty_path(&self, path: ast::Path) -> P<ast::Ty> { self.ty(path.span, ast::TyKind::Path(None, path)) } @@ -140,11 +144,26 @@ impl<'a> ExtCtxt<'a> { ast::Lifetime { id: ast::DUMMY_NODE_ID, ident: ident.with_span_pos(span) } } + pub fn lifetime_static(&self, span: Span) -> ast::Lifetime { + self.lifetime(span, Ident::new(kw::StaticLifetime, span)) + } + pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt { ast::Stmt { id: ast::DUMMY_NODE_ID, span: expr.span, kind: ast::StmtKind::Expr(expr) } } pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: Ident, ex: P<ast::Expr>) -> ast::Stmt { + self.stmt_let_ty(sp, mutbl, ident, None, ex) + } + + pub fn stmt_let_ty( + &self, + sp: Span, + mutbl: bool, + ident: Ident, + ty: Option<P<ast::Ty>>, + ex: P<ast::Expr>, + ) -> ast::Stmt { let pat = if mutbl { let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Mut); self.pat_ident_binding_mode(sp, ident, binding_mode) @@ -153,7 +172,7 @@ impl<'a> ExtCtxt<'a> { }; let local = P(ast::Local { pat, - ty: None, + ty, id: ast::DUMMY_NODE_ID, kind: LocalKind::Init(ex), span: sp, diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 8a6941a4516..48766c67910 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -567,8 +567,10 @@ symbols! { debug_assert_ne_macro, debug_assertions, debug_struct, + debug_struct_fields_finish, debug_trait_builder, debug_tuple, + debug_tuple_fields_finish, debugger_visualizer, decl_macro, declare_lint_pass, diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs index 9e4a574818a..1d4be42b4a2 100644 --- a/library/core/src/fmt/mod.rs +++ b/library/core/src/fmt/mod.rs @@ -4,6 +4,7 @@ use crate::cell::{Cell, Ref, RefCell, RefMut, SyncUnsafeCell, UnsafeCell}; use crate::char::EscapeDebugExtArgs; +use crate::iter; use crate::marker::PhantomData; use crate::mem; use crate::num::fmt as numfmt; @@ -693,7 +694,7 @@ pub(crate) mod macros { /// Derive macro generating an impl of the trait `Debug`. #[rustc_builtin_macro] #[stable(feature = "builtin_macro_prelude", since = "1.38.0")] - #[allow_internal_unstable(core_intrinsics)] + #[allow_internal_unstable(core_intrinsics, fmt_helpers_for_derive)] pub macro Debug($item:item) { /* compiler built-in */ } @@ -1964,6 +1965,129 @@ impl<'a> Formatter<'a> { builders::debug_struct_new(self, name) } + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_struct_fields_finish` is more general, but this is faster for 1 field. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_field1_finish<'b>( + &'b mut self, + name: &str, + name1: &str, + value1: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_struct_new(self, name); + builder.field(name1, value1); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_struct_fields_finish` is more general, but this is faster for 2 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_field2_finish<'b>( + &'b mut self, + name: &str, + name1: &str, + value1: &dyn Debug, + name2: &str, + value2: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_struct_new(self, name); + builder.field(name1, value1); + builder.field(name2, value2); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_struct_fields_finish` is more general, but this is faster for 3 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_field3_finish<'b>( + &'b mut self, + name: &str, + name1: &str, + value1: &dyn Debug, + name2: &str, + value2: &dyn Debug, + name3: &str, + value3: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_struct_new(self, name); + builder.field(name1, value1); + builder.field(name2, value2); + builder.field(name3, value3); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_struct_fields_finish` is more general, but this is faster for 4 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_field4_finish<'b>( + &'b mut self, + name: &str, + name1: &str, + value1: &dyn Debug, + name2: &str, + value2: &dyn Debug, + name3: &str, + value3: &dyn Debug, + name4: &str, + value4: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_struct_new(self, name); + builder.field(name1, value1); + builder.field(name2, value2); + builder.field(name3, value3); + builder.field(name4, value4); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_struct_fields_finish` is more general, but this is faster for 5 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_field5_finish<'b>( + &'b mut self, + name: &str, + name1: &str, + value1: &dyn Debug, + name2: &str, + value2: &dyn Debug, + name3: &str, + value3: &dyn Debug, + name4: &str, + value4: &dyn Debug, + name5: &str, + value5: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_struct_new(self, name); + builder.field(name1, value1); + builder.field(name2, value2); + builder.field(name3, value3); + builder.field(name4, value4); + builder.field(name5, value5); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// For the cases not covered by `debug_struct_field[12345]_finish`. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_struct_fields_finish<'b>( + &'b mut self, + name: &str, + names: &[&str], + values: &[&dyn Debug], + ) -> Result { + assert_eq!(names.len(), values.len()); + let mut builder = builders::debug_struct_new(self, name); + for (name, value) in iter::zip(names, values) { + builder.field(name, value); + } + builder.finish() + } + /// Creates a `DebugTuple` builder designed to assist with creation of /// `fmt::Debug` implementations for tuple structs. /// @@ -1995,6 +2119,108 @@ impl<'a> Formatter<'a> { builders::debug_tuple_new(self, name) } + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_tuple_fields_finish` is more general, but this is faster for 1 field. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_field1_finish<'b>(&'b mut self, name: &str, value1: &dyn Debug) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + builder.field(value1); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_tuple_fields_finish` is more general, but this is faster for 2 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_field2_finish<'b>( + &'b mut self, + name: &str, + value1: &dyn Debug, + value2: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + builder.field(value1); + builder.field(value2); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_tuple_fields_finish` is more general, but this is faster for 3 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_field3_finish<'b>( + &'b mut self, + name: &str, + value1: &dyn Debug, + value2: &dyn Debug, + value3: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + builder.field(value1); + builder.field(value2); + builder.field(value3); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_tuple_fields_finish` is more general, but this is faster for 4 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_field4_finish<'b>( + &'b mut self, + name: &str, + value1: &dyn Debug, + value2: &dyn Debug, + value3: &dyn Debug, + value4: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + builder.field(value1); + builder.field(value2); + builder.field(value3); + builder.field(value4); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// `debug_tuple_fields_finish` is more general, but this is faster for 5 fields. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_field5_finish<'b>( + &'b mut self, + name: &str, + value1: &dyn Debug, + value2: &dyn Debug, + value3: &dyn Debug, + value4: &dyn Debug, + value5: &dyn Debug, + ) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + builder.field(value1); + builder.field(value2); + builder.field(value3); + builder.field(value4); + builder.field(value5); + builder.finish() + } + + /// Used to shrink `derive(Debug)` code, for faster compilation and smaller binaries. + /// For the cases not covered by `debug_tuple_field[12345]_finish`. + #[doc(hidden)] + #[unstable(feature = "fmt_helpers_for_derive", issue = "none")] + pub fn debug_tuple_fields_finish<'b>( + &'b mut self, + name: &str, + values: &[&dyn Debug], + ) -> Result { + let mut builder = builders::debug_tuple_new(self, name); + for value in values { + builder.field(value); + } + builder.finish() + } + /// Creates a `DebugList` builder designed to assist with creation of /// `fmt::Debug` implementations for list-like structures. /// |