diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs | 67 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs | 59 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/lib.rs | 6 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 4 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/llvm_util.rs | 30 |
5 files changed, 84 insertions, 82 deletions
diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs index a573a37beb3..4f2af732527 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs @@ -75,10 +75,10 @@ pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) { // Encode all filenames referenced by coverage mappings in this CGU. let filenames_buffer = global_file_table.make_filenames_buffer(tcx); - - let filenames_size = filenames_buffer.len(); - let filenames_val = cx.const_bytes(&filenames_buffer); - let filenames_ref = llvm_cov::hash_bytes(&filenames_buffer); + // The `llvm-cov` tool uses this hash to associate each covfun record with + // its corresponding filenames table, since the final binary will typically + // contain multiple covmap records from different compilation units. + let filenames_hash = llvm_cov::hash_bytes(&filenames_buffer); let mut unused_function_names = Vec::new(); @@ -101,7 +101,7 @@ pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) { for covfun in &covfun_records { unused_function_names.extend(covfun.mangled_function_name_if_unused()); - covfun::generate_covfun_record(cx, filenames_ref, covfun) + covfun::generate_covfun_record(cx, filenames_hash, covfun) } // For unused functions, we need to take their mangled names and store them @@ -126,7 +126,7 @@ pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) { // Generate the coverage map header, which contains the filenames used by // this CGU's coverage mappings, and store it in a well-known global. // (This is skipped if we returned early due to having no covfun records.) - generate_covmap_record(cx, covmap_version, filenames_size, filenames_val); + generate_covmap_record(cx, covmap_version, &filenames_buffer); } /// Maps "global" (per-CGU) file ID numbers to their underlying filenames. @@ -225,38 +225,35 @@ fn span_file_name(tcx: TyCtxt<'_>, span: Span) -> Symbol { /// Generates the contents of the covmap record for this CGU, which mostly /// consists of a header and a list of filenames. The record is then stored /// as a global variable in the `__llvm_covmap` section. -fn generate_covmap_record<'ll>( - cx: &CodegenCx<'ll, '_>, - version: u32, - filenames_size: usize, - filenames_val: &'ll llvm::Value, -) { - debug!("cov map: filenames_size = {}, 0-based version = {}", filenames_size, version); - - // Create the coverage data header (Note, fields 0 and 2 are now always zero, - // as of `llvm::coverage::CovMapVersion::Version4`.) - let zero_was_n_records_val = cx.const_u32(0); - let filenames_size_val = cx.const_u32(filenames_size as u32); - let zero_was_coverage_size_val = cx.const_u32(0); - let version_val = cx.const_u32(version); - let cov_data_header_val = cx.const_struct( - &[zero_was_n_records_val, filenames_size_val, zero_was_coverage_size_val, version_val], - /*packed=*/ false, +fn generate_covmap_record<'ll>(cx: &CodegenCx<'ll, '_>, version: u32, filenames_buffer: &[u8]) { + // A covmap record consists of four target-endian u32 values, followed by + // the encoded filenames table. Two of the header fields are unused in + // modern versions of the LLVM coverage mapping format, and are always 0. + // <https://llvm.org/docs/CoverageMappingFormat.html#llvm-ir-representation> + // See also `src/llvm-project/clang/lib/CodeGen/CoverageMappingGen.cpp`. + let covmap_header = cx.const_struct( + &[ + cx.const_u32(0), // (unused) + cx.const_u32(filenames_buffer.len() as u32), + cx.const_u32(0), // (unused) + cx.const_u32(version), + ], + /* packed */ false, ); - - // Create the complete LLVM coverage data value to add to the LLVM IR - let covmap_data = - cx.const_struct(&[cov_data_header_val, filenames_val], /*packed=*/ false); - - let llglobal = llvm::add_global(cx.llmod, cx.val_ty(covmap_data), &llvm_cov::covmap_var_name()); - llvm::set_initializer(llglobal, covmap_data); - llvm::set_global_constant(llglobal, true); - llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage); - llvm::set_section(llglobal, &llvm_cov::covmap_section_name(cx.llmod)); + let covmap_record = cx + .const_struct(&[covmap_header, cx.const_bytes(filenames_buffer)], /* packed */ false); + + let covmap_global = + llvm::add_global(cx.llmod, cx.val_ty(covmap_record), &llvm_cov::covmap_var_name()); + llvm::set_initializer(covmap_global, covmap_record); + llvm::set_global_constant(covmap_global, true); + llvm::set_linkage(covmap_global, llvm::Linkage::PrivateLinkage); + llvm::set_section(covmap_global, &llvm_cov::covmap_section_name(cx.llmod)); // LLVM's coverage mapping format specifies 8-byte alignment for items in this section. // <https://llvm.org/docs/CoverageMappingFormat.html> - llvm::set_alignment(llglobal, Align::EIGHT); - cx.add_used_global(llglobal); + llvm::set_alignment(covmap_global, Align::EIGHT); + + cx.add_used_global(covmap_global); } /// Each CGU will normally only emit coverage metadata for the functions that it actually generates. diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs index 530e6827f55..33e7a0f2f20 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs @@ -136,7 +136,7 @@ fn fill_region_tables<'tcx>( /// as a global variable in the `__llvm_covfun` section. pub(crate) fn generate_covfun_record<'tcx>( cx: &CodegenCx<'_, 'tcx>, - filenames_ref: u64, + filenames_hash: u64, covfun: &CovfunRecord<'tcx>, ) { let &CovfunRecord { @@ -155,46 +155,45 @@ pub(crate) fn generate_covfun_record<'tcx>( regions, ); - // Concatenate the encoded coverage mappings - let coverage_mapping_size = coverage_mapping_buffer.len(); - let coverage_mapping_val = cx.const_bytes(&coverage_mapping_buffer); - + // A covfun record consists of four target-endian integers, followed by the + // encoded mapping data in bytes. Note that the length field is 32 bits. + // <https://llvm.org/docs/CoverageMappingFormat.html#llvm-ir-representation> + // See also `src/llvm-project/clang/lib/CodeGen/CoverageMappingGen.cpp` and + // `COVMAP_V3` in `src/llvm-project/llvm/include/llvm/ProfileData/InstrProfData.inc`. let func_name_hash = llvm_cov::hash_bytes(mangled_function_name.as_bytes()); - let func_name_hash_val = cx.const_u64(func_name_hash); - let coverage_mapping_size_val = cx.const_u32(coverage_mapping_size as u32); - let source_hash_val = cx.const_u64(source_hash); - let filenames_ref_val = cx.const_u64(filenames_ref); - let func_record_val = cx.const_struct( + let covfun_record = cx.const_struct( &[ - func_name_hash_val, - coverage_mapping_size_val, - source_hash_val, - filenames_ref_val, - coverage_mapping_val, + cx.const_u64(func_name_hash), + cx.const_u32(coverage_mapping_buffer.len() as u32), + cx.const_u64(source_hash), + cx.const_u64(filenames_hash), + cx.const_bytes(&coverage_mapping_buffer), ], - /*packed=*/ true, + // This struct needs to be packed, so that the 32-bit length field + // doesn't have unexpected padding. + true, ); // Choose a variable name to hold this function's covfun data. // Functions that are used have a suffix ("u") to distinguish them from // unused copies of the same function (from different CGUs), so that if a // linker sees both it won't discard the used copy's data. - let func_record_var_name = - CString::new(format!("__covrec_{:X}{}", func_name_hash, if is_used { "u" } else { "" })) - .unwrap(); - debug!("function record var name: {:?}", func_record_var_name); - - let llglobal = llvm::add_global(cx.llmod, cx.val_ty(func_record_val), &func_record_var_name); - llvm::set_initializer(llglobal, func_record_val); - llvm::set_global_constant(llglobal, true); - llvm::set_linkage(llglobal, llvm::Linkage::LinkOnceODRLinkage); - llvm::set_visibility(llglobal, llvm::Visibility::Hidden); - llvm::set_section(llglobal, cx.covfun_section_name()); + let u = if is_used { "u" } else { "" }; + let covfun_var_name = CString::new(format!("__covrec_{func_name_hash:X}{u}")).unwrap(); + debug!("function record var name: {covfun_var_name:?}"); + + let covfun_global = llvm::add_global(cx.llmod, cx.val_ty(covfun_record), &covfun_var_name); + llvm::set_initializer(covfun_global, covfun_record); + llvm::set_global_constant(covfun_global, true); + llvm::set_linkage(covfun_global, llvm::Linkage::LinkOnceODRLinkage); + llvm::set_visibility(covfun_global, llvm::Visibility::Hidden); + llvm::set_section(covfun_global, cx.covfun_section_name()); // LLVM's coverage mapping format specifies 8-byte alignment for items in this section. // <https://llvm.org/docs/CoverageMappingFormat.html> - llvm::set_alignment(llglobal, Align::EIGHT); + llvm::set_alignment(covfun_global, Align::EIGHT); if cx.target_spec().supports_comdat() { - llvm::set_comdat(cx.llmod, llglobal, &func_record_var_name); + llvm::set_comdat(cx.llmod, covfun_global, &covfun_var_name); } - cx.add_used_global(llglobal); + + cx.add_used_global(covfun_global); } diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs index 5235891a18d..af8562db054 100644 --- a/compiler/rustc_codegen_llvm/src/lib.rs +++ b/compiler/rustc_codegen_llvm/src/lib.rs @@ -27,7 +27,7 @@ use std::mem::ManuallyDrop; use back::owned_target_machine::OwnedTargetMachine; use back::write::{create_informational_target_machine, create_target_machine}; use errors::ParseTargetMachineConfig; -pub use llvm_util::target_features; +pub use llvm_util::target_features_cfg; use rustc_ast::expand::allocator::AllocatorKind; use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule}; use rustc_codegen_ssa::back::write::{ @@ -330,8 +330,8 @@ impl CodegenBackend for LlvmCodegenBackend { llvm_util::print_version(); } - fn target_features(&self, sess: &Session, allow_unstable: bool) -> Vec<Symbol> { - target_features(sess, allow_unstable) + fn target_features_cfg(&self, sess: &Session, allow_unstable: bool) -> Vec<Symbol> { + target_features_cfg(sess, allow_unstable) } fn codegen_crate<'tcx>( diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index 8b4523bd252..d62632d1431 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -17,7 +17,9 @@ use super::debuginfo::{ DebugEmissionKind, DebugNameTableKind, }; -pub type Bool = c_uint; +/// In the LLVM-C API, boolean values are passed as `typedef int LLVMBool`, +/// which has a different ABI from Rust or C++ `bool`. +pub type Bool = c_int; pub const True: Bool = 1 as Bool; pub const False: Bool = 0 as Bool; diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs index 07eb89e6041..bfec7d708cf 100644 --- a/compiler/rustc_codegen_llvm/src/llvm_util.rs +++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs @@ -17,7 +17,7 @@ use rustc_session::Session; use rustc_session::config::{PrintKind, PrintRequest}; use rustc_span::symbol::Symbol; use rustc_target::spec::{MergeFunctions, PanicStrategy, SmallDataThresholdSupport}; -use rustc_target::target_features::{RUSTC_SPECIAL_FEATURES, RUSTC_SPECIFIC_FEATURES, Stability}; +use rustc_target::target_features::{RUSTC_SPECIAL_FEATURES, RUSTC_SPECIFIC_FEATURES}; use crate::back::write::create_informational_target_machine; use crate::errors::{ @@ -300,7 +300,7 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea /// Must express features in the way Rust understands them. /// /// We do not have to worry about RUSTC_SPECIFIC_FEATURES here, those are handled outside codegen. -pub fn target_features(sess: &Session, allow_unstable: bool) -> Vec<Symbol> { +pub fn target_features_cfg(sess: &Session, allow_unstable: bool) -> Vec<Symbol> { let mut features: FxHashSet<Symbol> = Default::default(); // Add base features for the target. @@ -316,7 +316,7 @@ pub fn target_features(sess: &Session, allow_unstable: bool) -> Vec<Symbol> { sess.target .rust_target_features() .iter() - .filter(|(_, gate, _)| gate.is_supported()) + .filter(|(_, gate, _)| gate.in_cfg()) .filter(|(feature, _, _)| { // skip checking special features, as LLVM may not understand them if RUSTC_SPECIAL_FEATURES.contains(feature) { @@ -372,9 +372,9 @@ pub fn target_features(sess: &Session, allow_unstable: bool) -> Vec<Symbol> { sess.target .rust_target_features() .iter() - .filter(|(_, gate, _)| gate.is_supported()) + .filter(|(_, gate, _)| gate.in_cfg()) .filter_map(|&(feature, gate, _)| { - if sess.is_nightly_build() || allow_unstable || gate.is_stable() { + if sess.is_nightly_build() || allow_unstable || gate.requires_nightly().is_none() { Some(feature) } else { None @@ -493,7 +493,7 @@ fn print_target_features(sess: &Session, tm: &llvm::TargetMachine, out: &mut Str .rust_target_features() .iter() .filter_map(|(feature, gate, _implied)| { - if !gate.is_supported() { + if !gate.in_cfg() { // Only list (experimentally) supported features. return None; } @@ -716,13 +716,17 @@ pub(crate) fn global_llvm_features( }; sess.dcx().emit_warn(unknown_feature); } - Some((_, Stability::Stable, _)) => {} - Some((_, Stability::Unstable(_), _)) => { - // An unstable feature. Warn about using it. - sess.dcx().emit_warn(UnstableCTargetFeature { feature }); - } - Some((_, Stability::Forbidden { reason }, _)) => { - sess.dcx().emit_warn(ForbiddenCTargetFeature { feature, reason }); + Some((_, stability, _)) => { + if let Err(reason) = + stability.compute_toggleability(&sess.target).allow_toggle() + { + sess.dcx().emit_warn(ForbiddenCTargetFeature { feature, reason }); + } else if stability.requires_nightly().is_some() { + // An unstable feature. Warn about using it. It makes little sense + // to hard-error here since we just warn about fully unknown + // features above. + sess.dcx().emit_warn(UnstableCTargetFeature { feature }); + } } } |