diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/context.rs | 31 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs | 17 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/debuginfo/mod.rs | 15 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 31 |
4 files changed, 80 insertions, 14 deletions
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index bb16bc5dccd..8672459b5da 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -215,16 +215,19 @@ pub unsafe fn create_module<'ll>( // to ensure intrinsic calls don't use it. if !sess.needs_plt() { let avoid_plt = "RtLibUseGOT\0".as_ptr().cast(); - llvm::LLVMRustAddModuleFlag(llmod, avoid_plt, 1); + llvm::LLVMRustAddModuleFlag(llmod, llvm::LLVMModFlagBehavior::Warning, avoid_plt, 1); } if sess.is_sanitizer_cfi_enabled() { // FIXME(rcvalle): Add support for non canonical jump tables. let canonical_jump_tables = "CFI Canonical Jump Tables\0".as_ptr().cast(); - // FIXME(rcvalle): Add it with Override behavior flag--LLVMRustAddModuleFlag adds it with - // Warning behavior flag. Add support for specifying the behavior flag to - // LLVMRustAddModuleFlag. - llvm::LLVMRustAddModuleFlag(llmod, canonical_jump_tables, 1); + // FIXME(rcvalle): Add it with Override behavior flag. + llvm::LLVMRustAddModuleFlag( + llmod, + llvm::LLVMModFlagBehavior::Warning, + canonical_jump_tables, + 1, + ); } // Control Flow Guard is currently only supported by the MSVC linker on Windows. @@ -233,11 +236,21 @@ pub unsafe fn create_module<'ll>( CFGuard::Disabled => {} CFGuard::NoChecks => { // Set `cfguard=1` module flag to emit metadata only. - llvm::LLVMRustAddModuleFlag(llmod, "cfguard\0".as_ptr() as *const _, 1) + llvm::LLVMRustAddModuleFlag( + llmod, + llvm::LLVMModFlagBehavior::Warning, + "cfguard\0".as_ptr() as *const _, + 1, + ) } CFGuard::Checks => { // Set `cfguard=2` module flag to emit metadata and checks. - llvm::LLVMRustAddModuleFlag(llmod, "cfguard\0".as_ptr() as *const _, 2) + llvm::LLVMRustAddModuleFlag( + llmod, + llvm::LLVMModFlagBehavior::Warning, + "cfguard\0".as_ptr() as *const _, + 2, + ) } } } @@ -247,24 +260,28 @@ pub unsafe fn create_module<'ll>( llvm::LLVMRustAddModuleFlag( llmod, + llvm::LLVMModFlagBehavior::Error, "branch-target-enforcement\0".as_ptr().cast(), bti.into(), ); llvm::LLVMRustAddModuleFlag( llmod, + llvm::LLVMModFlagBehavior::Error, "sign-return-address\0".as_ptr().cast(), pac.is_some().into(), ); let pac_opts = pac.unwrap_or(PacRet { leaf: false, key: PAuthKey::A }); llvm::LLVMRustAddModuleFlag( llmod, + llvm::LLVMModFlagBehavior::Error, "sign-return-address-all\0".as_ptr().cast(), pac_opts.leaf.into(), ); let is_bkey = if pac_opts.key == PAuthKey::A { false } else { true }; llvm::LLVMRustAddModuleFlag( llmod, + llvm::LLVMModFlagBehavior::Error, "sign-return-address-with-bkey\0".as_ptr().cast(), is_bkey.into(), ); diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs index 32f18419753..3014d2f1930 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs @@ -9,6 +9,7 @@ use rustc_data_structures::fx::FxIndexSet; use rustc_hir::def::DefKind; use rustc_hir::def_id::DefIdSet; use rustc_llvm::RustString; +use rustc_middle::bug; use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags; use rustc_middle::mir::coverage::CodeRegion; use rustc_middle::ty::TyCtxt; @@ -76,10 +77,18 @@ pub fn finalize<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) { let coverage_mapping_buffer = llvm::build_byte_buffer(|coverage_mapping_buffer| { mapgen.write_coverage_mapping(expressions, counter_regions, coverage_mapping_buffer); }); - debug_assert!( - !coverage_mapping_buffer.is_empty(), - "Every `FunctionCoverage` should have at least one counter" - ); + + if coverage_mapping_buffer.is_empty() { + if function_coverage.is_used() { + bug!( + "A used function should have had coverage mapping data but did not: {}", + mangled_function_name + ); + } else { + debug!("unused function had no coverage mapping data: {}", mangled_function_name); + continue; + } + } function_data.push((mangled_function_name, source_hash, is_used, coverage_mapping_buffer)); } diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs index 61e49fab6ff..28eb8e2a0a4 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs @@ -108,18 +108,29 @@ impl<'a, 'tcx> CrateDebugContext<'a, 'tcx> { // This can be overridden using --llvm-opts -dwarf-version,N. // Android has the same issue (#22398) if let Some(version) = sess.target.dwarf_version { - llvm::LLVMRustAddModuleFlag(self.llmod, "Dwarf Version\0".as_ptr().cast(), version) + llvm::LLVMRustAddModuleFlag( + self.llmod, + llvm::LLVMModFlagBehavior::Warning, + "Dwarf Version\0".as_ptr().cast(), + version, + ) } // Indicate that we want CodeView debug information on MSVC if sess.target.is_like_msvc { - llvm::LLVMRustAddModuleFlag(self.llmod, "CodeView\0".as_ptr().cast(), 1) + llvm::LLVMRustAddModuleFlag( + self.llmod, + llvm::LLVMModFlagBehavior::Warning, + "CodeView\0".as_ptr().cast(), + 1, + ) } // Prevent bitcode readers from deleting the debug info. let ptr = "Debug Info Version\0".as_ptr(); llvm::LLVMRustAddModuleFlag( self.llmod, + llvm::LLVMModFlagBehavior::Warning, ptr.cast(), llvm::LLVMRustDebugMetadataVersion(), ); diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index a1c7d2b4f61..2b102188790 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -61,6 +61,26 @@ pub enum LLVMMachineType { ARM = 0x01c0, } +/// LLVM's Module::ModFlagBehavior, defined in llvm/include/llvm/IR/Module.h. +/// +/// When merging modules (e.g. during LTO), their metadata flags are combined. Conflicts are +/// resolved according to the merge behaviors specified here. Flags differing only in merge +/// behavior are still considered to be in conflict. +/// +/// In order for Rust-C LTO to work, we must specify behaviors compatible with Clang. Notably, +/// 'Error' and 'Warning' cannot be mixed for a given flag. +#[derive(Copy, Clone, PartialEq)] +#[repr(C)] +pub enum LLVMModFlagBehavior { + Error = 1, + Warning = 2, + Require = 3, + Override = 4, + Append = 5, + AppendUnique = 6, + Max = 7, +} + // Consts for the LLVM CallConv type, pre-cast to usize. /// LLVM CallingConv::ID. Should we wrap this? @@ -1895,7 +1915,16 @@ extern "C" { pub fn LLVMRustIsRustLLVM() -> bool; - pub fn LLVMRustAddModuleFlag(M: &Module, name: *const c_char, value: u32); + /// Add LLVM module flags. + /// + /// In order for Rust-C LTO to work, module flags must be compatible with Clang. What + /// "compatible" means depends on the merge behaviors involved. + pub fn LLVMRustAddModuleFlag( + M: &Module, + merge_behavior: LLVMModFlagBehavior, + name: *const c_char, + value: u32, + ); pub fn LLVMRustMetadataAsValue<'a>(C: &'a Context, MD: &'a Metadata) -> &'a Value; |
