diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/builder.rs | 126 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/consts.rs | 7 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs | 158 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs | 70 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/intrinsic.rs | 27 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 4 |
6 files changed, 378 insertions, 14 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs index 160f361b9b5..4c2bdb2f5ec 100644 --- a/compiler/rustc_codegen_llvm/src/builder.rs +++ b/compiler/rustc_codegen_llvm/src/builder.rs @@ -17,7 +17,7 @@ use rustc_data_structures::small_c_str::SmallCStr; use rustc_hir::def_id::DefId; use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs; use rustc_middle::ty::layout::{ - FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout, + FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTyCtxt, LayoutError, LayoutOfHelpers, TyAndLayout, }; use rustc_middle::ty::{self, Instance, Ty, TyCtxt}; use rustc_sanitizers::{cfi, kcfi}; @@ -1702,4 +1702,128 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> { }; kcfi_bundle } + + pub(crate) fn mcdc_parameters( + &mut self, + fn_name: &'ll Value, + hash: &'ll Value, + bitmap_bytes: &'ll Value, + ) -> &'ll Value { + debug!("mcdc_parameters() with args ({:?}, {:?}, {:?})", fn_name, hash, bitmap_bytes); + + assert!(llvm_util::get_version() >= (18, 0, 0), "MCDC intrinsics require LLVM 18 or later"); + + let llfn = unsafe { llvm::LLVMRustGetInstrProfMCDCParametersIntrinsic(self.cx().llmod) }; + let llty = self.cx.type_func( + &[self.cx.type_ptr(), self.cx.type_i64(), self.cx.type_i32()], + self.cx.type_void(), + ); + let args = &[fn_name, hash, bitmap_bytes]; + let args = self.check_call("call", llty, llfn, args); + + unsafe { + let _ = llvm::LLVMRustBuildCall( + self.llbuilder, + llty, + llfn, + args.as_ptr() as *const &llvm::Value, + args.len() as c_uint, + [].as_ptr(), + 0 as c_uint, + ); + // Create condition bitmap named `mcdc.addr`. + let mut bx = Builder::with_cx(self.cx); + bx.position_at_start(llvm::LLVMGetFirstBasicBlock(self.llfn())); + let cond_bitmap = { + let alloca = + llvm::LLVMBuildAlloca(bx.llbuilder, bx.cx.type_i32(), c"mcdc.addr".as_ptr()); + llvm::LLVMSetAlignment(alloca, 4); + alloca + }; + bx.store(self.const_i32(0), cond_bitmap, self.tcx().data_layout.i32_align.abi); + cond_bitmap + } + } + + pub(crate) fn mcdc_tvbitmap_update( + &mut self, + fn_name: &'ll Value, + hash: &'ll Value, + bitmap_bytes: &'ll Value, + bitmap_index: &'ll Value, + mcdc_temp: &'ll Value, + ) { + debug!( + "mcdc_tvbitmap_update() with args ({:?}, {:?}, {:?}, {:?}, {:?})", + fn_name, hash, bitmap_bytes, bitmap_index, mcdc_temp + ); + assert!(llvm_util::get_version() >= (18, 0, 0), "MCDC intrinsics require LLVM 18 or later"); + + let llfn = + unsafe { llvm::LLVMRustGetInstrProfMCDCTVBitmapUpdateIntrinsic(self.cx().llmod) }; + let llty = self.cx.type_func( + &[ + self.cx.type_ptr(), + self.cx.type_i64(), + self.cx.type_i32(), + self.cx.type_i32(), + self.cx.type_ptr(), + ], + self.cx.type_void(), + ); + let args = &[fn_name, hash, bitmap_bytes, bitmap_index, mcdc_temp]; + let args = self.check_call("call", llty, llfn, args); + unsafe { + let _ = llvm::LLVMRustBuildCall( + self.llbuilder, + llty, + llfn, + args.as_ptr() as *const &llvm::Value, + args.len() as c_uint, + [].as_ptr(), + 0 as c_uint, + ); + } + let i32_align = self.tcx().data_layout.i32_align.abi; + self.store(self.const_i32(0), mcdc_temp, i32_align); + } + + pub(crate) fn mcdc_condbitmap_update( + &mut self, + fn_name: &'ll Value, + hash: &'ll Value, + cond_loc: &'ll Value, + mcdc_temp: &'ll Value, + bool_value: &'ll Value, + ) { + debug!( + "mcdc_condbitmap_update() with args ({:?}, {:?}, {:?}, {:?}, {:?})", + fn_name, hash, cond_loc, mcdc_temp, bool_value + ); + assert!(llvm_util::get_version() >= (18, 0, 0), "MCDC intrinsics require LLVM 18 or later"); + let llfn = unsafe { llvm::LLVMRustGetInstrProfMCDCCondBitmapIntrinsic(self.cx().llmod) }; + let llty = self.cx.type_func( + &[ + self.cx.type_ptr(), + self.cx.type_i64(), + self.cx.type_i32(), + self.cx.type_ptr(), + self.cx.type_i1(), + ], + self.cx.type_void(), + ); + let args = &[fn_name, hash, cond_loc, mcdc_temp, bool_value]; + self.check_call("call", llty, llfn, args); + unsafe { + let _ = llvm::LLVMRustBuildCall( + self.llbuilder, + llty, + llfn, + args.as_ptr() as *const &llvm::Value, + args.len() as c_uint, + [].as_ptr(), + 0 as c_uint, + ); + } + } } diff --git a/compiler/rustc_codegen_llvm/src/consts.rs b/compiler/rustc_codegen_llvm/src/consts.rs index a62dfe13204..9e85c2d88f9 100644 --- a/compiler/rustc_codegen_llvm/src/consts.rs +++ b/compiler/rustc_codegen_llvm/src/consts.rs @@ -260,7 +260,8 @@ impl<'ll> CodegenCx<'ll, '_> { #[instrument(level = "debug", skip(self, llty))] pub(crate) fn get_static_inner(&self, def_id: DefId, llty: &'ll Type) -> &'ll Value { - if let Some(&g) = self.instances.borrow().get(&Instance::mono(self.tcx, def_id)) { + let instance = Instance::mono(self.tcx, def_id); + if let Some(&g) = self.instances.borrow().get(&instance) { trace!("used cached value"); return g; } @@ -273,7 +274,7 @@ impl<'ll> CodegenCx<'ll, '_> { statics defined in the same CGU, but did not for `{def_id:?}`" ); - let sym = self.tcx.symbol_name(Instance::mono(self.tcx, def_id)).name; + let sym = self.tcx.symbol_name(instance).name; let fn_attrs = self.tcx.codegen_fn_attrs(def_id); debug!(?sym, ?fn_attrs); @@ -363,7 +364,7 @@ impl<'ll> CodegenCx<'ll, '_> { } } - self.instances.borrow_mut().insert(Instance::mono(self.tcx, def_id), g); + self.instances.borrow_mut().insert(instance, g); g } diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs index 2af28146a51..12a846a49ec 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs @@ -1,4 +1,6 @@ -use rustc_middle::mir::coverage::{CodeRegion, CounterId, CovTerm, ExpressionId, MappingKind}; +use rustc_middle::mir::coverage::{ + CodeRegion, ConditionInfo, CounterId, CovTerm, DecisionInfo, ExpressionId, MappingKind, +}; /// Must match the layout of `LLVMRustCounterKind`. #[derive(Copy, Clone, Debug)] @@ -99,6 +101,86 @@ pub enum RegionKind { /// associated with two counters, each representing the number of times the /// expression evaluates to true or false. BranchRegion = 4, + + /// A DecisionRegion represents a top-level boolean expression and is + /// associated with a variable length bitmap index and condition number. + MCDCDecisionRegion = 5, + + /// A Branch Region can be extended to include IDs to facilitate MC/DC. + MCDCBranchRegion = 6, +} + +pub mod mcdc { + use rustc_middle::mir::coverage::{ConditionInfo, DecisionInfo}; + + /// Must match the layout of `LLVMRustMCDCDecisionParameters`. + #[repr(C)] + #[derive(Clone, Copy, Debug, Default)] + pub struct DecisionParameters { + bitmap_idx: u32, + conditions_num: u16, + } + + // ConditionId in llvm is `unsigned int` at 18 while `int16_t` at [19](https://github.com/llvm/llvm-project/pull/81257) + type LLVMConditionId = i16; + + /// Must match the layout of `LLVMRustMCDCBranchParameters`. + #[repr(C)] + #[derive(Clone, Copy, Debug, Default)] + pub struct BranchParameters { + condition_id: LLVMConditionId, + condition_ids: [LLVMConditionId; 2], + } + + #[repr(C)] + #[derive(Clone, Copy, Debug)] + pub enum ParameterTag { + None = 0, + Decision = 1, + Branch = 2, + } + /// Same layout with `LLVMRustMCDCParameters` + #[repr(C)] + #[derive(Clone, Copy, Debug)] + pub struct Parameters { + tag: ParameterTag, + decision_params: DecisionParameters, + branch_params: BranchParameters, + } + + impl Parameters { + pub fn none() -> Self { + Self { + tag: ParameterTag::None, + decision_params: Default::default(), + branch_params: Default::default(), + } + } + pub fn decision(decision_params: DecisionParameters) -> Self { + Self { tag: ParameterTag::Decision, decision_params, branch_params: Default::default() } + } + pub fn branch(branch_params: BranchParameters) -> Self { + Self { tag: ParameterTag::Branch, decision_params: Default::default(), branch_params } + } + } + + impl From<ConditionInfo> for BranchParameters { + fn from(value: ConditionInfo) -> Self { + Self { + condition_id: value.condition_id.as_u32() as LLVMConditionId, + condition_ids: [ + value.false_next_id.as_u32() as LLVMConditionId, + value.true_next_id.as_u32() as LLVMConditionId, + ], + } + } + } + + impl From<DecisionInfo> for DecisionParameters { + fn from(value: DecisionInfo) -> Self { + Self { bitmap_idx: value.bitmap_idx, conditions_num: value.conditions_num } + } + } } /// This struct provides LLVM's representation of a "CoverageMappingRegion", encoded into the @@ -122,6 +204,7 @@ pub struct CounterMappingRegion { /// for the false branch of the region. false_counter: Counter, + mcdc_params: mcdc::Parameters, /// An indirect reference to the source filename. In the LLVM Coverage Mapping Format, the /// file_id is an index into a function-specific `virtual_file_mapping` array of indexes /// that, in turn, are used to look up the filename for this region. @@ -173,6 +256,26 @@ impl CounterMappingRegion { end_line, end_col, ), + MappingKind::MCDCBranch { true_term, false_term, mcdc_params } => { + Self::mcdc_branch_region( + Counter::from_term(true_term), + Counter::from_term(false_term), + mcdc_params, + local_file_id, + start_line, + start_col, + end_line, + end_col, + ) + } + MappingKind::MCDCDecision(decision_info) => Self::decision_region( + decision_info, + local_file_id, + start_line, + start_col, + end_line, + end_col, + ), } } @@ -187,6 +290,7 @@ impl CounterMappingRegion { Self { counter, false_counter: Counter::ZERO, + mcdc_params: mcdc::Parameters::none(), file_id, expanded_file_id: 0, start_line, @@ -209,6 +313,7 @@ impl CounterMappingRegion { Self { counter, false_counter, + mcdc_params: mcdc::Parameters::none(), file_id, expanded_file_id: 0, start_line, @@ -219,6 +324,54 @@ impl CounterMappingRegion { } } + pub(crate) fn mcdc_branch_region( + counter: Counter, + false_counter: Counter, + condition_info: ConditionInfo, + file_id: u32, + start_line: u32, + start_col: u32, + end_line: u32, + end_col: u32, + ) -> Self { + Self { + counter, + false_counter, + mcdc_params: mcdc::Parameters::branch(condition_info.into()), + file_id, + expanded_file_id: 0, + start_line, + start_col, + end_line, + end_col, + kind: RegionKind::MCDCBranchRegion, + } + } + + pub(crate) fn decision_region( + decision_info: DecisionInfo, + file_id: u32, + start_line: u32, + start_col: u32, + end_line: u32, + end_col: u32, + ) -> Self { + let mcdc_params = mcdc::Parameters::decision(decision_info.into()); + + Self { + counter: Counter::ZERO, + false_counter: Counter::ZERO, + mcdc_params, + file_id, + expanded_file_id: 0, + start_line, + start_col, + end_line, + end_col, + kind: RegionKind::MCDCDecisionRegion, + } + } + // This function might be used in the future; the LLVM API is still evolving, as is coverage // support. #[allow(dead_code)] @@ -233,6 +386,7 @@ impl CounterMappingRegion { Self { counter: Counter::ZERO, false_counter: Counter::ZERO, + mcdc_params: mcdc::Parameters::none(), file_id, expanded_file_id, start_line, @@ -256,6 +410,7 @@ impl CounterMappingRegion { Self { counter: Counter::ZERO, false_counter: Counter::ZERO, + mcdc_params: mcdc::Parameters::none(), file_id, expanded_file_id: 0, start_line, @@ -280,6 +435,7 @@ impl CounterMappingRegion { Self { counter, false_counter: Counter::ZERO, + mcdc_params: mcdc::Parameters::none(), file_id, expanded_file_id: 0, start_line, diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs index 140566e8da9..085ce15d81f 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs @@ -13,7 +13,7 @@ use rustc_codegen_ssa::traits::{ use rustc_data_structures::fx::{FxHashMap, FxIndexMap}; use rustc_llvm::RustString; use rustc_middle::bug; -use rustc_middle::mir::coverage::CoverageKind; +use rustc_middle::mir::coverage::{CoverageKind, FunctionCoverageInfo}; use rustc_middle::ty::layout::HasTyCtxt; use rustc_middle::ty::Instance; use rustc_target::abi::Align; @@ -30,6 +30,7 @@ pub struct CrateCoverageContext<'ll, 'tcx> { pub(crate) function_coverage_map: RefCell<FxIndexMap<Instance<'tcx>, FunctionCoverageCollector<'tcx>>>, pub(crate) pgo_func_name_var_map: RefCell<FxHashMap<Instance<'tcx>, &'ll llvm::Value>>, + pub(crate) mcdc_condition_bitmap_map: RefCell<FxHashMap<Instance<'tcx>, &'ll llvm::Value>>, } impl<'ll, 'tcx> CrateCoverageContext<'ll, 'tcx> { @@ -37,6 +38,7 @@ impl<'ll, 'tcx> CrateCoverageContext<'ll, 'tcx> { Self { function_coverage_map: Default::default(), pgo_func_name_var_map: Default::default(), + mcdc_condition_bitmap_map: Default::default(), } } @@ -45,6 +47,12 @@ impl<'ll, 'tcx> CrateCoverageContext<'ll, 'tcx> { ) -> FxIndexMap<Instance<'tcx>, FunctionCoverageCollector<'tcx>> { self.function_coverage_map.replace(FxIndexMap::default()) } + + /// LLVM use a temp value to record evaluated mcdc test vector of each decision, which is called condition bitmap. + /// This value is named `mcdc.addr` (same as clang) and is a 32-bit integer. + fn try_get_mcdc_condition_bitmap(&self, instance: &Instance<'tcx>) -> Option<&'ll llvm::Value> { + self.mcdc_condition_bitmap_map.borrow().get(instance).copied() + } } // These methods used to be part of trait `CoverageInfoMethods`, which no longer @@ -90,6 +98,10 @@ impl<'tcx> CoverageInfoBuilderMethods<'tcx> for Builder<'_, '_, 'tcx> { return; }; + if function_coverage_info.mcdc_bitmap_bytes > 0 { + ensure_mcdc_parameters(bx, instance, function_coverage_info); + } + let Some(coverage_context) = bx.coverage_context() else { return }; let mut coverage_map = coverage_context.function_coverage_map.borrow_mut(); let func_coverage = coverage_map @@ -131,10 +143,66 @@ impl<'tcx> CoverageInfoBuilderMethods<'tcx> for Builder<'_, '_, 'tcx> { CoverageKind::ExpressionUsed { id } => { func_coverage.mark_expression_id_seen(id); } + CoverageKind::CondBitmapUpdate { id, value, .. } => { + drop(coverage_map); + assert_ne!( + id.as_u32(), + 0, + "ConditionId of evaluated conditions should never be zero" + ); + let cond_bitmap = coverage_context + .try_get_mcdc_condition_bitmap(&instance) + .expect("mcdc cond bitmap should have been allocated for updating"); + let cond_loc = bx.const_i32(id.as_u32() as i32 - 1); + let bool_value = bx.const_bool(value); + let fn_name = bx.get_pgo_func_name_var(instance); + let hash = bx.const_u64(function_coverage_info.function_source_hash); + bx.mcdc_condbitmap_update(fn_name, hash, cond_loc, cond_bitmap, bool_value); + } + CoverageKind::TestVectorBitmapUpdate { bitmap_idx } => { + drop(coverage_map); + let cond_bitmap = coverage_context + .try_get_mcdc_condition_bitmap(&instance) + .expect("mcdc cond bitmap should have been allocated for merging into the global bitmap"); + let bitmap_bytes = bx.tcx().coverage_ids_info(instance.def).mcdc_bitmap_bytes; + assert!(bitmap_idx < bitmap_bytes, "bitmap index of the decision out of range"); + assert!( + bitmap_bytes <= function_coverage_info.mcdc_bitmap_bytes, + "bitmap length disagreement: query says {bitmap_bytes} but function info only has {}", + function_coverage_info.mcdc_bitmap_bytes + ); + + let fn_name = bx.get_pgo_func_name_var(instance); + let hash = bx.const_u64(function_coverage_info.function_source_hash); + let bitmap_bytes = bx.const_u32(bitmap_bytes); + let bitmap_index = bx.const_u32(bitmap_idx); + bx.mcdc_tvbitmap_update(fn_name, hash, bitmap_bytes, bitmap_index, cond_bitmap); + } } } } +fn ensure_mcdc_parameters<'ll, 'tcx>( + bx: &mut Builder<'_, 'll, 'tcx>, + instance: Instance<'tcx>, + function_coverage_info: &FunctionCoverageInfo, +) { + let Some(cx) = bx.coverage_context() else { return }; + if cx.mcdc_condition_bitmap_map.borrow().contains_key(&instance) { + return; + } + + let fn_name = bx.get_pgo_func_name_var(instance); + let hash = bx.const_u64(function_coverage_info.function_source_hash); + let bitmap_bytes = bx.const_u32(function_coverage_info.mcdc_bitmap_bytes); + let cond_bitmap = bx.mcdc_parameters(fn_name, hash, bitmap_bytes); + bx.coverage_context() + .expect("already checked above") + .mcdc_condition_bitmap_map + .borrow_mut() + .insert(instance, cond_bitmap); +} + /// Calls llvm::createPGOFuncNameVar() with the given function instance's /// mangled function name. The LLVM API returns an llvm::GlobalVariable /// containing the function name, with the specific variable name and linkage diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs index 2bed7c1bd1c..ab9f20fdf63 100644 --- a/compiler/rustc_codegen_llvm/src/intrinsic.rs +++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs @@ -315,25 +315,32 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> { Some((width, signed)) => match name { sym::ctlz | sym::cttz => { let y = self.const_bool(false); - self.call_intrinsic( + let ret = self.call_intrinsic( &format!("llvm.{name}.i{width}"), &[args[0].immediate(), y], - ) + ); + + self.intcast(ret, llret_ty, false) } sym::ctlz_nonzero => { let y = self.const_bool(true); let llvm_name = &format!("llvm.ctlz.i{width}"); - self.call_intrinsic(llvm_name, &[args[0].immediate(), y]) + let ret = self.call_intrinsic(llvm_name, &[args[0].immediate(), y]); + self.intcast(ret, llret_ty, false) } sym::cttz_nonzero => { let y = self.const_bool(true); let llvm_name = &format!("llvm.cttz.i{width}"); - self.call_intrinsic(llvm_name, &[args[0].immediate(), y]) + let ret = self.call_intrinsic(llvm_name, &[args[0].immediate(), y]); + self.intcast(ret, llret_ty, false) + } + sym::ctpop => { + let ret = self.call_intrinsic( + &format!("llvm.ctpop.i{width}"), + &[args[0].immediate()], + ); + self.intcast(ret, llret_ty, false) } - sym::ctpop => self.call_intrinsic( - &format!("llvm.ctpop.i{width}"), - &[args[0].immediate()], - ), sym::bswap => { if width == 8 { args[0].immediate() // byte swap a u8/i8 is just a no-op @@ -355,6 +362,10 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> { // rotate = funnel shift with first two args the same let llvm_name = &format!("llvm.fsh{}.i{}", if is_left { 'l' } else { 'r' }, width); + + // llvm expects shift to be the same type as the values, but rust always uses `u32` + let raw_shift = self.intcast(raw_shift, self.val_ty(val), false); + self.call_intrinsic(llvm_name, &[val, val, raw_shift]) } sym::saturating_add | sym::saturating_sub => { diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index 83158f6f1d5..a10dc61967e 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -1631,6 +1631,10 @@ extern "C" { // Miscellaneous instructions pub fn LLVMRustGetInstrProfIncrementIntrinsic(M: &Module) -> &Value; + pub fn LLVMRustGetInstrProfMCDCParametersIntrinsic(M: &Module) -> &Value; + pub fn LLVMRustGetInstrProfMCDCTVBitmapUpdateIntrinsic(M: &Module) -> &Value; + pub fn LLVMRustGetInstrProfMCDCCondBitmapIntrinsic(M: &Module) -> &Value; + pub fn LLVMRustBuildCall<'a>( B: &Builder<'a>, Ty: &'a Type, |