From 0504a333837e10f19454901fd060c0f99bf8f5b7 Mon Sep 17 00:00:00 2001 From: Julia Tatz Date: Tue, 6 Apr 2021 16:00:35 -0400 Subject: [PATCH 1/3] Preserve, clarify, and extend debug information `-Cdebuginfo=1` was never line tables only and can't be due to backwards compatibility issues. This was clarified and an option for line tables only was added. Additionally an option for line info directives only was added, which is well needed for some targets. The debug info options should now behave the same as clang's debug info options. --- .../src/debuginfo/metadata.rs | 19 +----------- .../rustc_codegen_llvm/src/debuginfo/mod.rs | 2 +- compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 6 ++-- compiler/rustc_codegen_ssa/src/back/linker.rs | 5 +++- compiler/rustc_interface/src/tests.rs | 3 +- .../rustc_llvm/llvm-wrapper/RustWrapper.cpp | 3 ++ compiler/rustc_session/src/config.rs | 29 ++++--------------- compiler/rustc_session/src/options.rs | 19 ++++++++++-- src/doc/rustc/src/codegen-options/index.md | 8 +++-- tests/codegen/debug-limited.rs | 28 ++++++++++++++++++ tests/codegen/debug-line-directives-only.rs | 28 ++++++++++++++++++ tests/codegen/debug-line-tables-only.rs | 28 ++++++++++++++++++ tests/rustdoc-ui/c-help.stdout | 2 +- 13 files changed, 126 insertions(+), 54 deletions(-) create mode 100644 tests/codegen/debug-limited.rs create mode 100644 tests/codegen/debug-line-directives-only.rs create mode 100644 tests/codegen/debug-line-tables-only.rs diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs index e2a592d851a8c..4bf6762d1f604 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs @@ -830,24 +830,7 @@ pub fn build_compile_unit_di_node<'ll, 'tcx>( } .unwrap_or_default(); let split_name = split_name.to_str().unwrap(); - - // FIXME(#60020): - // - // This should actually be - // - // let kind = DebugEmissionKind::from_generic(tcx.sess.opts.debuginfo); - // - // That is, we should set LLVM's emission kind to `LineTablesOnly` if - // we are compiling with "limited" debuginfo. However, some of the - // existing tools relied on slightly more debuginfo being generated than - // would be the case with `LineTablesOnly`, and we did not want to break - // these tools in a "drive-by fix", without a good idea or plan about - // what limited debuginfo should exactly look like. So for now we keep - // the emission kind as `FullDebug`. - // - // See https://github.com/rust-lang/rust/issues/60020 for details. - let kind = DebugEmissionKind::FullDebug; - assert!(tcx.sess.opts.debuginfo != DebugInfo::None); + let kind = DebugEmissionKind::from_generic(tcx.sess.opts.debuginfo); unsafe { let compile_unit_file = llvm::LLVMRustDIBuilderCreateFile( diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs index 5392534cfcb79..41a75c9d775f2 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs @@ -402,7 +402,7 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> { cx: &CodegenCx<'ll, 'tcx>, fn_abi: &FnAbi<'tcx, Ty<'tcx>>, ) -> &'ll DIArray { - if cx.sess().opts.debuginfo == DebugInfo::Limited { + if cx.sess().opts.debuginfo != DebugInfo::Full { return create_DIArray(DIB(cx), &[]); } diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index 0d63e634ad888..aff352abab469 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -946,6 +946,7 @@ pub mod debuginfo { NoDebug, FullDebug, LineTablesOnly, + DebugDirectivesOnly, } impl DebugEmissionKind { @@ -953,8 +954,9 @@ pub mod debuginfo { use rustc_session::config::DebugInfo; match kind { DebugInfo::None => DebugEmissionKind::NoDebug, - DebugInfo::Limited => DebugEmissionKind::LineTablesOnly, - DebugInfo::Full => DebugEmissionKind::FullDebug, + DebugInfo::LineDirectivesOnly => DebugEmissionKind::DebugDirectivesOnly, + DebugInfo::LineTablesOnly => DebugEmissionKind::LineTablesOnly, + DebugInfo::Limited | DebugInfo::Full => DebugEmissionKind::FullDebug, } } } diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs index 69bb00f804d3c..65dfc325a118f 100644 --- a/compiler/rustc_codegen_ssa/src/back/linker.rs +++ b/compiler/rustc_codegen_ssa/src/back/linker.rs @@ -1121,9 +1121,12 @@ impl<'a> Linker for EmLinker<'a> { fn debuginfo(&mut self, _strip: Strip, _: &[PathBuf]) { // Preserve names or generate source maps depending on debug info + // For more information see https://emscripten.org/docs/tools_reference/emcc.html#emcc-g self.cmd.arg(match self.sess.opts.debuginfo { DebugInfo::None => "-g0", - DebugInfo::Limited => "--profiling-funcs", + DebugInfo::Limited | DebugInfo::LineTablesOnly | DebugInfo::LineDirectivesOnly => { + "--profiling-funcs" + } DebugInfo::Full => "-g", }); } diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs index eb5990507fb6d..10dfd32d418a2 100644 --- a/compiler/rustc_interface/src/tests.rs +++ b/compiler/rustc_interface/src/tests.rs @@ -5,6 +5,7 @@ use rustc_data_structures::fx::FxHashSet; use rustc_data_structures::profiling::TimePassesFormat; use rustc_errors::{emitter::HumanReadableErrorType, registry, ColorConfig}; use rustc_session::config::rustc_optgroups; +use rustc_session::config::DebugInfo; use rustc_session::config::Input; use rustc_session::config::InstrumentXRay; use rustc_session::config::TraitSolver; @@ -574,7 +575,7 @@ fn test_codegen_options_tracking_hash() { tracked!(code_model, Some(CodeModel::Large)); tracked!(control_flow_guard, CFGuard::Checks); tracked!(debug_assertions, Some(true)); - tracked!(debuginfo, 0xdeadbeef); + tracked!(debuginfo, DebugInfo::Limited); tracked!(embed_bitcode, false); tracked!(force_frame_pointers, Some(false)); tracked!(force_unwind_tables, Some(true)); diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp index e3493caaaf74e..6a2fd5aa6e6a3 100644 --- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp +++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp @@ -682,6 +682,7 @@ enum class LLVMRustDebugEmissionKind { NoDebug, FullDebug, LineTablesOnly, + DebugDirectivesOnly, }; static DICompileUnit::DebugEmissionKind fromRust(LLVMRustDebugEmissionKind Kind) { @@ -692,6 +693,8 @@ static DICompileUnit::DebugEmissionKind fromRust(LLVMRustDebugEmissionKind Kind) return DICompileUnit::DebugEmissionKind::FullDebug; case LLVMRustDebugEmissionKind::LineTablesOnly: return DICompileUnit::DebugEmissionKind::LineTablesOnly; + case LLVMRustDebugEmissionKind::DebugDirectivesOnly: + return DICompileUnit::DebugEmissionKind::DebugDirectivesOnly; default: report_fatal_error("bad DebugEmissionKind."); } diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs index 485c3f554625a..1d8fedb8bd792 100644 --- a/compiler/rustc_session/src/config.rs +++ b/compiler/rustc_session/src/config.rs @@ -260,6 +260,8 @@ pub enum SymbolManglingVersion { #[derive(Clone, Copy, Debug, PartialEq, Hash)] pub enum DebugInfo { None, + LineDirectivesOnly, + LineTablesOnly, Limited, Full, } @@ -1979,11 +1981,7 @@ fn parse_opt_level( } } -fn select_debuginfo( - matches: &getopts::Matches, - cg: &CodegenOptions, - error_format: ErrorOutputType, -) -> DebugInfo { +fn select_debuginfo(matches: &getopts::Matches, cg: &CodegenOptions) -> DebugInfo { let max_g = matches.opt_positions("g").into_iter().max(); let max_c = matches .opt_strs_pos("C") @@ -1993,24 +1991,7 @@ fn select_debuginfo( if let Some("debuginfo") = s.split('=').next() { Some(i) } else { None } }) .max(); - if max_g > max_c { - DebugInfo::Full - } else { - match cg.debuginfo { - 0 => DebugInfo::None, - 1 => DebugInfo::Limited, - 2 => DebugInfo::Full, - arg => { - early_error( - error_format, - &format!( - "debug info level needs to be between \ - 0-2 (instead was `{arg}`)" - ), - ); - } - } - } + if max_g > max_c { DebugInfo::Full } else { cg.debuginfo } } pub(crate) fn parse_assert_incr_state( @@ -2498,7 +2479,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options { // to use them interchangeably. See the note above (regarding `-O` and `-C opt-level`) // for more details. let debug_assertions = cg.debug_assertions.unwrap_or(opt_level == OptLevel::No); - let debuginfo = select_debuginfo(matches, &cg, error_format); + let debuginfo = select_debuginfo(matches, &cg); let mut search_paths = vec![]; for s in &matches.opt_strs("L") { diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs index c75af48e80af4..953d6561669fe 100644 --- a/compiler/rustc_session/src/options.rs +++ b/compiler/rustc_session/src/options.rs @@ -377,6 +377,7 @@ mod desc { pub const parse_cfguard: &str = "either a boolean (`yes`, `no`, `on`, `off`, etc), `checks`, or `nochecks`"; pub const parse_cfprotection: &str = "`none`|`no`|`n` (default), `branch`, `return`, or `full`|`yes`|`y` (equivalent to `branch` and `return`)"; + pub const parse_debuginfo: &str = "either an integer (0, 1, 2), `none`, `line-directives-only`, `line-tables-only`, `limited`, or `full`"; pub const parse_strip: &str = "either `none`, `debuginfo`, or `symbols`"; pub const parse_linker_flavor: &str = ::rustc_target::spec::LinkerFlavorCli::one_of(); pub const parse_optimization_fuel: &str = "crate=integer"; @@ -767,6 +768,18 @@ mod parse { true } + pub(crate) fn parse_debuginfo(slot: &mut DebugInfo, v: Option<&str>) -> bool { + match v { + Some("0") | Some("none") => *slot = DebugInfo::None, + Some("line-directives-only") => *slot = DebugInfo::LineDirectivesOnly, + Some("line-tables-only") => *slot = DebugInfo::LineTablesOnly, + Some("1") | Some("limited") => *slot = DebugInfo::Limited, + Some("2") | Some("full") => *slot = DebugInfo::Full, + _ => return false, + } + true + } + pub(crate) fn parse_linker_flavor(slot: &mut Option, v: Option<&str>) -> bool { match v.and_then(LinkerFlavorCli::from_str) { Some(lf) => *slot = Some(lf), @@ -1217,9 +1230,9 @@ options! { "use Windows Control Flow Guard (default: no)"), debug_assertions: Option = (None, parse_opt_bool, [TRACKED], "explicitly enable the `cfg(debug_assertions)` directive"), - debuginfo: usize = (0, parse_number, [TRACKED], - "debug info emission level (0 = no debug info, 1 = line tables only, \ - 2 = full debug info with variable and type information; default: 0)"), + debuginfo: DebugInfo = (DebugInfo::None, parse_debuginfo, [TRACKED], + "debug info emission level (0-2, none, line-directives-only, \ + line-tables-only, limited, or full; default: 0)"), default_linker_libraries: bool = (false, parse_bool, [UNTRACKED], "allow the linker to link its default libraries (default: no)"), embed_bitcode: bool = (true, parse_bool, [TRACKED], diff --git a/src/doc/rustc/src/codegen-options/index.md b/src/doc/rustc/src/codegen-options/index.md index c7f120dafeafd..8b4f1cd2d4169 100644 --- a/src/doc/rustc/src/codegen-options/index.md +++ b/src/doc/rustc/src/codegen-options/index.md @@ -71,9 +71,11 @@ If not specified, debug assertions are automatically enabled only if the This flag controls the generation of debug information. It takes one of the following values: -* `0`: no debug info at all (the default). -* `1`: line tables only. -* `2`: full debug info. +* `0` or `none`: no debug info at all (the default). +* `line-directives-only`: line info directives only. +* `line-tables-only`: line tables only. +* `1` or `limited`: debug info without type information. +* `2` or `full`: full debug info. Note: The [`-g` flag][option-g-debug] is an alias for `-C debuginfo=2`. diff --git a/tests/codegen/debug-limited.rs b/tests/codegen/debug-limited.rs new file mode 100644 index 0000000000000..fafee0ef583a4 --- /dev/null +++ b/tests/codegen/debug-limited.rs @@ -0,0 +1,28 @@ +// Verify that the limited debuginfo option emits llvm's FullDebugInfo, but no type info. +// +// ignore-windows +// compile-flags: -C debuginfo=limited + +#[repr(C)] +struct StructType { + a: i64, + b: i32 +} + +extern "C" { + fn creator() -> *mut StructType; + fn save(p: *const StructType); +} + +fn main() { + unsafe { + let value: &mut StructType = &mut* creator(); + value.a = 7; + save(value as *const StructType) + } +} + +// CHECK: !DICompileUnit +// CHECK: emissionKind: FullDebug +// CHECK: !DILocation +// CHECK-NOT: !DIBasicType diff --git a/tests/codegen/debug-line-directives-only.rs b/tests/codegen/debug-line-directives-only.rs new file mode 100644 index 0000000000000..0dd22931b30a5 --- /dev/null +++ b/tests/codegen/debug-line-directives-only.rs @@ -0,0 +1,28 @@ +// Verify that the only debuginfo generated are the line directives. +// +// ignore-windows +// compile-flags: -C debuginfo=line-directives-only + +#[repr(C)] +struct StructType { + a: i64, + b: i32 +} + +extern "C" { + fn creator() -> *mut StructType; + fn save(p: *const StructType); +} + +fn main() { + unsafe { + let value: &mut StructType = &mut* creator(); + value.a = 7; + save(value as *const StructType) + } +} + +// CHECK: !DICompileUnit +// CHECK: emissionKind: DebugDirectivesOnly +// CHECK: !DILocation +// CHECK-NOT: !DIBasicType diff --git a/tests/codegen/debug-line-tables-only.rs b/tests/codegen/debug-line-tables-only.rs new file mode 100644 index 0000000000000..3d109d4ae519f --- /dev/null +++ b/tests/codegen/debug-line-tables-only.rs @@ -0,0 +1,28 @@ +// Verify that the only debuginfo generated are the line tables. +// +// ignore-windows +// compile-flags: -C debuginfo=line-tables-only + +#[repr(C)] +struct StructType { + a: i64, + b: i32 +} + +extern "C" { + fn creator() -> *mut StructType; + fn save(p: *const StructType); +} + +fn main() { + unsafe { + let value: &mut StructType = &mut* creator(); + value.a = 7; + save(value as *const StructType) + } +} + +// CHECK: !DICompileUnit +// CHECK: emissionKind: LineTablesOnly +// CHECK: !DILocation +// CHECK-NOT: !DIBasicType diff --git a/tests/rustdoc-ui/c-help.stdout b/tests/rustdoc-ui/c-help.stdout index 75b2e2a2a43f4..0bd2d73efee53 100644 --- a/tests/rustdoc-ui/c-help.stdout +++ b/tests/rustdoc-ui/c-help.stdout @@ -3,7 +3,7 @@ -C codegen-units=val -- divide crate into N units to optimize in parallel -C control-flow-guard=val -- use Windows Control Flow Guard (default: no) -C debug-assertions=val -- explicitly enable the `cfg(debug_assertions)` directive - -C debuginfo=val -- debug info emission level (0 = no debug info, 1 = line tables only, 2 = full debug info with variable and type information; default: 0) + -C debuginfo=val -- debug info emission level (0-2, none, line-directives-only, line-tables-only, limited, or full; default: 0) -C default-linker-libraries=val -- allow the linker to link its default libraries (default: no) -C embed-bitcode=val -- emit bitcode in rlibs (default: yes) -C extra-filename=val -- extra data to put in each output filename From 7b453b9f5a3b921291fd723067d48fee28e7475b Mon Sep 17 00:00:00 2001 From: Julia Tatz Date: Fri, 3 Sep 2021 13:00:39 -0400 Subject: [PATCH 2/3] More in-depth documentation for the new debuginfo options --- compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 10 ++++++++++ src/doc/rustc/src/codegen-options/index.md | 4 ++-- tests/codegen/debug-limited.rs | 5 ++--- tests/codegen/debug-line-directives-only.rs | 5 ++--- tests/codegen/debug-line-tables-only.rs | 5 ++--- 5 files changed, 18 insertions(+), 11 deletions(-) diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index aff352abab469..556c6602ff430 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -951,6 +951,16 @@ pub mod debuginfo { impl DebugEmissionKind { pub fn from_generic(kind: rustc_session::config::DebugInfo) -> Self { + // We should be setting LLVM's emission kind to `LineTablesOnly` if + // we are compiling with "limited" debuginfo. However, some of the + // existing tools relied on slightly more debuginfo being generated than + // would be the case with `LineTablesOnly`, and we did not want to break + // these tools in a "drive-by fix", without a good idea or plan about + // what limited debuginfo should exactly look like. So for now we are + // instead adding a new debuginfo option "line-tables-only" so as to + // not break anything and to allow users to have 'limited' debug info. + // + // See https://github.com/rust-lang/rust/issues/60020 for details. use rustc_session::config::DebugInfo; match kind { DebugInfo::None => DebugEmissionKind::NoDebug, diff --git a/src/doc/rustc/src/codegen-options/index.md b/src/doc/rustc/src/codegen-options/index.md index 8b4f1cd2d4169..4d418f9c9b746 100644 --- a/src/doc/rustc/src/codegen-options/index.md +++ b/src/doc/rustc/src/codegen-options/index.md @@ -72,8 +72,8 @@ This flag controls the generation of debug information. It takes one of the following values: * `0` or `none`: no debug info at all (the default). -* `line-directives-only`: line info directives only. -* `line-tables-only`: line tables only. +* `line-directives-only`: line info directives only, (For the nvptx* targets this enables [profiling](https://reviews.llvm.org/D46061), but on other targets the behavior is unspecified). +* `line-tables-only`: line tables only, (Generates the minimal amount of debug info for backtraces with filename/line number info, but not anything else, i.e. variable or function parameter info). * `1` or `limited`: debug info without type information. * `2` or `full`: full debug info. diff --git a/tests/codegen/debug-limited.rs b/tests/codegen/debug-limited.rs index fafee0ef583a4..48d676887fdd5 100644 --- a/tests/codegen/debug-limited.rs +++ b/tests/codegen/debug-limited.rs @@ -1,12 +1,11 @@ // Verify that the limited debuginfo option emits llvm's FullDebugInfo, but no type info. // -// ignore-windows // compile-flags: -C debuginfo=limited #[repr(C)] struct StructType { a: i64, - b: i32 + b: i32, } extern "C" { @@ -16,7 +15,7 @@ extern "C" { fn main() { unsafe { - let value: &mut StructType = &mut* creator(); + let value: &mut StructType = &mut *creator(); value.a = 7; save(value as *const StructType) } diff --git a/tests/codegen/debug-line-directives-only.rs b/tests/codegen/debug-line-directives-only.rs index 0dd22931b30a5..750bdd49de075 100644 --- a/tests/codegen/debug-line-directives-only.rs +++ b/tests/codegen/debug-line-directives-only.rs @@ -1,12 +1,11 @@ // Verify that the only debuginfo generated are the line directives. // -// ignore-windows // compile-flags: -C debuginfo=line-directives-only #[repr(C)] struct StructType { a: i64, - b: i32 + b: i32, } extern "C" { @@ -16,7 +15,7 @@ extern "C" { fn main() { unsafe { - let value: &mut StructType = &mut* creator(); + let value: &mut StructType = &mut *creator(); value.a = 7; save(value as *const StructType) } diff --git a/tests/codegen/debug-line-tables-only.rs b/tests/codegen/debug-line-tables-only.rs index 3d109d4ae519f..3ed165a6f6967 100644 --- a/tests/codegen/debug-line-tables-only.rs +++ b/tests/codegen/debug-line-tables-only.rs @@ -1,12 +1,11 @@ // Verify that the only debuginfo generated are the line tables. // -// ignore-windows // compile-flags: -C debuginfo=line-tables-only #[repr(C)] struct StructType { a: i64, - b: i32 + b: i32, } extern "C" { @@ -16,7 +15,7 @@ extern "C" { fn main() { unsafe { - let value: &mut StructType = &mut* creator(); + let value: &mut StructType = &mut *creator(); value.a = 7; save(value as *const StructType) } From 92b759137178c732ea541134cede507b606e0a0d Mon Sep 17 00:00:00 2001 From: jyn Date: Tue, 4 Apr 2023 07:37:33 -0400 Subject: [PATCH 3/3] Add a best guess at what `line-directives-only` means --- src/doc/rustc/src/codegen-options/index.md | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/doc/rustc/src/codegen-options/index.md b/src/doc/rustc/src/codegen-options/index.md index 4d418f9c9b746..62347f169a5eb 100644 --- a/src/doc/rustc/src/codegen-options/index.md +++ b/src/doc/rustc/src/codegen-options/index.md @@ -72,9 +72,9 @@ This flag controls the generation of debug information. It takes one of the following values: * `0` or `none`: no debug info at all (the default). -* `line-directives-only`: line info directives only, (For the nvptx* targets this enables [profiling](https://reviews.llvm.org/D46061), but on other targets the behavior is unspecified). -* `line-tables-only`: line tables only, (Generates the minimal amount of debug info for backtraces with filename/line number info, but not anything else, i.e. variable or function parameter info). -* `1` or `limited`: debug info without type information. +* `line-directives-only`: line info directives only. For the nvptx* targets this enables [profiling](https://reviews.llvm.org/D46061). For other use cases, `line-tables-only` is the better, more compatible choice. +* `line-tables-only`: line tables only. Generates the minimal amount of debug info for backtraces with filename/line number info, but not anything else, i.e. no variable or function parameter info. +* `1` or `limited`: debug info without type or variable-level information. * `2` or `full`: full debug info. Note: The [`-g` flag][option-g-debug] is an alias for `-C debuginfo=2`.