From 05783c8ed68f7b393d28f5df64f98d3d1eee5537 Mon Sep 17 00:00:00 2001 From: Mark Rousskov Date: Sun, 17 Mar 2024 22:26:39 -0400 Subject: [PATCH 1/5] Codegen const panic messages as function calls This skips emitting extra arguments at every callsite (of which there can be many). For a librustc_driver build with overflow checks enabled, this cuts 0.7MB from the resulting binary. --- example/mini_core.rs | 30 ++++++++++++++++++++++++++++++ src/base.rs | 24 ++++++++---------------- 2 files changed, 38 insertions(+), 16 deletions(-) diff --git a/example/mini_core.rs b/example/mini_core.rs index 39988cf64e54..1cee51319078 100644 --- a/example/mini_core.rs +++ b/example/mini_core.rs @@ -465,6 +465,36 @@ pub fn panic(_msg: &'static str) -> ! { } } +macro_rules! panic_const { + ($($lang:ident = $message:expr,)+) => { + #[cfg(not(bootstrap))] + pub mod panic_const { + use super::*; + + $( + #[track_caller] + #[lang = stringify!($lang)] + pub fn $lang() -> ! { + panic($message); + } + )+ + } + } +} + +panic_const! { + panic_const_add_overflow = "attempt to add with overflow", + panic_const_sub_overflow = "attempt to subtract with overflow", + panic_const_mul_overflow = "attempt to multiply with overflow", + panic_const_div_overflow = "attempt to divide with overflow", + panic_const_rem_overflow = "attempt to calculate the remainder with overflow", + panic_const_neg_overflow = "attempt to negate with overflow", + panic_const_shr_overflow = "attempt to shift right with overflow", + panic_const_shl_overflow = "attempt to shift left with overflow", + panic_const_div_by_zero = "attempt to divide by zero", + panic_const_rem_by_zero = "attempt to calculate the remainder with a divisor of zero", +} + #[lang = "panic_bounds_check"] #[track_caller] fn panic_bounds_check(index: usize, len: usize) -> ! { diff --git a/src/base.rs b/src/base.rs index 2415c2c90b22..f597f084e70c 100644 --- a/src/base.rs +++ b/src/base.rs @@ -369,8 +369,14 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) { ); } _ => { - let msg_str = msg.description(); - codegen_panic(fx, msg_str, source_info); + let location = fx.get_caller_location(source_info).load_scalar(fx); + + codegen_panic_inner( + fx, + msg.panic_function(), + &[location], + Some(source_info.span), + ); } } } @@ -954,20 +960,6 @@ pub(crate) fn codegen_operand<'tcx>( } } -pub(crate) fn codegen_panic<'tcx>( - fx: &mut FunctionCx<'_, '_, 'tcx>, - msg_str: &str, - source_info: mir::SourceInfo, -) { - let location = fx.get_caller_location(source_info).load_scalar(fx); - - let msg_ptr = fx.anonymous_str(msg_str); - let msg_len = fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap()); - let args = [msg_ptr, msg_len, location]; - - codegen_panic_inner(fx, rustc_hir::LangItem::Panic, &args, Some(source_info.span)); -} - pub(crate) fn codegen_panic_nounwind<'tcx>( fx: &mut FunctionCx<'_, '_, 'tcx>, msg_str: &str, From 5de668acb07218424cbfe79f32f4961ca773570d Mon Sep 17 00:00:00 2001 From: Urgau Date: Tue, 19 Mar 2024 13:51:22 +0100 Subject: [PATCH 2/5] Replace `RemapFileNameExt::for_codegen` with explicit calls --- src/debuginfo/mod.rs | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/debuginfo/mod.rs b/src/debuginfo/mod.rs index 1bb0e5905137..c9f59ae9f29a 100644 --- a/src/debuginfo/mod.rs +++ b/src/debuginfo/mod.rs @@ -84,7 +84,9 @@ impl DebugContext { let mut dwarf = DwarfUnit::new(encoding); - let should_remap_filepaths = tcx.sess.should_prefer_remapped_for_codegen(); + use rustc_session::config::RemapPathScopeComponents; + let should_remap_filepaths = + tcx.sess.should_prefer_remapped(RemapPathScopeComponents::DEBUGINFO); let producer = producer(tcx.sess); let comp_dir = tcx From d6a817a7d9b8950cf73914d17cfc1c8e35dc2c7f Mon Sep 17 00:00:00 2001 From: Urgau Date: Tue, 19 Mar 2024 13:51:22 +0100 Subject: [PATCH 3/5] Make local_crate_source_file return a RealFileName so it can be remapped (or not) by callers --- src/debuginfo/mod.rs | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/src/debuginfo/mod.rs b/src/debuginfo/mod.rs index c9f59ae9f29a..222dc56a2b1b 100644 --- a/src/debuginfo/mod.rs +++ b/src/debuginfo/mod.rs @@ -99,9 +99,16 @@ impl DebugContext { FileNameDisplayPreference::Local }) .into_owned(); + let (name, file_info) = match tcx.sess.local_crate_source_file() { Some(path) => { - let name = path.to_string_lossy().into_owned(); + let name = path + .to_string_lossy(if should_remap_filepaths { + FileNameDisplayPreference::Remapped + } else { + FileNameDisplayPreference::Local + }) + .into_owned(); (name, None) } None => (tcx.crate_name(LOCAL_CRATE).to_string(), None), From 6a2b2b43bd65ee7e3def7e10289bb98ca415dc03 Mon Sep 17 00:00:00 2001 From: Urgau Date: Thu, 21 Mar 2024 21:13:06 +0100 Subject: [PATCH 4/5] Introduce `FileNameMapping::to_real_filename` and use it everywhere --- src/debuginfo/mod.rs | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/src/debuginfo/mod.rs b/src/debuginfo/mod.rs index 222dc56a2b1b..b661fa185b85 100644 --- a/src/debuginfo/mod.rs +++ b/src/debuginfo/mod.rs @@ -85,6 +85,8 @@ impl DebugContext { let mut dwarf = DwarfUnit::new(encoding); use rustc_session::config::RemapPathScopeComponents; + use rustc_session::RemapFileNameExt; + let should_remap_filepaths = tcx.sess.should_prefer_remapped(RemapPathScopeComponents::DEBUGINFO); @@ -93,22 +95,16 @@ impl DebugContext { .sess .opts .working_dir - .to_string_lossy(if should_remap_filepaths { - FileNameDisplayPreference::Remapped - } else { - FileNameDisplayPreference::Local - }) - .into_owned(); + .for_scope(tcx.sess, RemapPathScopeComponents::DEBUGINFO) + .to_string_lossy() + .to_string(); let (name, file_info) = match tcx.sess.local_crate_source_file() { Some(path) => { let name = path - .to_string_lossy(if should_remap_filepaths { - FileNameDisplayPreference::Remapped - } else { - FileNameDisplayPreference::Local - }) - .into_owned(); + .for_scope(tcx.sess, RemapPathScopeComponents::DEBUGINFO) + .to_string_lossy() + .to_string(); (name, None) } None => (tcx.crate_name(LOCAL_CRATE).to_string(), None), From 4d7ded634aab19de52b382794010563574f1507d Mon Sep 17 00:00:00 2001 From: Urgau Date: Fri, 22 Mar 2024 15:27:17 +0100 Subject: [PATCH 5/5] Replace Session should_remap_filepaths with filename_display_preference --- src/debuginfo/line_info.rs | 15 ++------------- src/debuginfo/mod.rs | 23 +++++++---------------- 2 files changed, 9 insertions(+), 29 deletions(-) diff --git a/src/debuginfo/line_info.rs b/src/debuginfo/line_info.rs index 380eba437c27..32b9c824ded2 100644 --- a/src/debuginfo/line_info.rs +++ b/src/debuginfo/line_info.rs @@ -89,11 +89,7 @@ impl DebugContext { match &source_file.name { FileName::Real(path) => { let (dir_path, file_name) = - split_path_dir_and_file(if self.should_remap_filepaths { - path.remapped_path_if_available() - } else { - path.local_path_if_available() - }); + split_path_dir_and_file(path.to_path(self.filename_display_preference)); let dir_name = osstr_as_utf8_bytes(dir_path.as_os_str()); let file_name = osstr_as_utf8_bytes(file_name); @@ -115,14 +111,7 @@ impl DebugContext { filename => { let dir_id = line_program.default_directory(); let dummy_file_name = LineString::new( - filename - .display(if self.should_remap_filepaths { - FileNameDisplayPreference::Remapped - } else { - FileNameDisplayPreference::Local - }) - .to_string() - .into_bytes(), + filename.display(self.filename_display_preference).to_string().into_bytes(), line_program.encoding(), line_strings, ); diff --git a/src/debuginfo/mod.rs b/src/debuginfo/mod.rs index b661fa185b85..5d943b5d9965 100644 --- a/src/debuginfo/mod.rs +++ b/src/debuginfo/mod.rs @@ -42,7 +42,7 @@ pub(crate) struct DebugContext { namespace_map: DefIdMap, array_size_type: UnitEntryId, - should_remap_filepaths: bool, + filename_display_preference: FileNameDisplayPreference, } pub(crate) struct FunctionDebugContext { @@ -85,26 +85,17 @@ impl DebugContext { let mut dwarf = DwarfUnit::new(encoding); use rustc_session::config::RemapPathScopeComponents; - use rustc_session::RemapFileNameExt; - let should_remap_filepaths = - tcx.sess.should_prefer_remapped(RemapPathScopeComponents::DEBUGINFO); + let filename_display_preference = + tcx.sess.filename_display_preference(RemapPathScopeComponents::DEBUGINFO); let producer = producer(tcx.sess); - let comp_dir = tcx - .sess - .opts - .working_dir - .for_scope(tcx.sess, RemapPathScopeComponents::DEBUGINFO) - .to_string_lossy() - .to_string(); + let comp_dir = + tcx.sess.opts.working_dir.to_string_lossy(filename_display_preference).to_string(); let (name, file_info) = match tcx.sess.local_crate_source_file() { Some(path) => { - let name = path - .for_scope(tcx.sess, RemapPathScopeComponents::DEBUGINFO) - .to_string_lossy() - .to_string(); + let name = path.to_string_lossy(filename_display_preference).to_string(); (name, None) } None => (tcx.crate_name(LOCAL_CRATE).to_string(), None), @@ -161,7 +152,7 @@ impl DebugContext { stack_pointer_register, namespace_map: DefIdMap::default(), array_size_type, - should_remap_filepaths, + filename_display_preference, } }