https://github.com/c-rhodes updated https://github.com/llvm/llvm-project/pull/165154
>From 11ef7520536c51b8ccb2c713631ae83f743ba7cd Mon Sep 17 00:00:00 2001 From: Michal R <[email protected]> Date: Mon, 20 Oct 2025 20:07:55 +0200 Subject: [PATCH 1/2] [BPF] Support for `DW_TAG_variant_part` in BTF generation (#155783) Variant part, represented by `DW_TAG_variant_part` is a structure with a discriminant and different variants, from which only one can be active and valid at the same time. The discriminant is the main difference between variant parts and unions represented by `DW_TAG_union` type. Variant parts are used by Rust enums, which look like: ```rust pub enum MyEnum { First { a: u32, b: i32 }, Second(u32), } ``` This type's debug info is the following `DICompositeType` with `DW_TAG_structure_type` tag: ```llvm !4 = !DICompositeType(tag: DW_TAG_structure_type, name: "MyEnum", scope: !2, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !6, templateParams: !16, identifier: "faba668fd9f71e9b7cf3b9ac5e8b93cb") ``` With one element being also a `DICompositeType`, but with `DW_TAG_variant_part` tag: ```llvm !6 = !{!7} !7 = !DICompositeType(tag: DW_TAG_variant_part, scope: !4, file: !5, size: 96, align: 32, elements: !8, templateParams: !16, identifier: "e4aee046fc86d111657622fdcb8c42f7", discriminator: !21) ``` Which has a discriminator: ```llvm !21 = !DIDerivedType(tag: DW_TAG_member, scope: !4, file: !5, baseType: !13, size: 32, align: 32, flags: DIFlagArtificial) ``` Which then holds different variants as `DIDerivedType` elements with `DW_TAG_member` tag: ```llvm !8 = !{!9, !17} !9 = !DIDerivedType(tag: DW_TAG_member, name: "First", scope: !7, file: !5, baseType: !10, size: 96, align: 32, extraData: i32 0) !10 = !DICompositeType(tag: DW_TAG_structure_type, name: "First", scope: !4, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !11, templateParams: !16, identifier: "cc7748c842e275452db4205b190c8ff7") !11 = !{!12, !14} !12 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !10, file: !5, baseType: !13, size: 32, align: 32, offset: 32, flags: DIFlagPublic) !13 = !DIBasicType(name: "u32", size: 32, encoding: DW_ATE_unsigned) !14 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !10, file: !5, baseType: !15, size: 32, align: 32, offset: 64, flags: DIFlagPublic) !15 = !DIBasicType(name: "i32", size: 32, encoding: DW_ATE_signed) !16 = !{} !17 = !DIDerivedType(tag: DW_TAG_member, name: "Second", scope: !7, file: !5, baseType: !18, size: 96, align: 32, extraData: i32 1) !18 = !DICompositeType(tag: DW_TAG_structure_type, name: "Second", scope: !4, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !19, templateParams: !16, identifier: "a2094b1381f3082d504fbd0903aa7c06") !19 = !{!20} !20 = !DIDerivedType(tag: DW_TAG_member, name: "__0", scope: !18, file: !5, baseType: !13, size: 32, align: 32, offset: 32, flags: DIFlagPublic) ``` BPF backend was assuming that all the elements of any `DICompositeType` have tag `DW_TAG_member` and are instances of `DIDerivedType`. However, the single element of the outer composite type `!4` has tag `DW_TAG_variant_part` and is an instance of `DICompositeType`. The unconditional call of `cast<DIDerivedType>` on all elements was causing an assertion failure when any Rust code with enums was compiled to the BPF target. Fix that by: * Handling `DW_TAG_variant_part` in `visitStructType`. * Replacing unconditional call of `cast<DIDerivedType>` over `DICompositeType` elements with a `switch` statement, handling both `DW_TAG_member` and `DW_TAG_variant_part` and casting the element to an appropriate type (`DIDerivedType` or `DICompositeType`). Fixes: https://github.com/llvm/llvm-project/issues/155778 --- llvm/lib/Target/BPF/BTFDebug.cpp | 112 ++++++++++++++++++---- llvm/test/CodeGen/BPF/BTF/variant-part.ll | 87 +++++++++++++++++ 2 files changed, 180 insertions(+), 19 deletions(-) create mode 100644 llvm/test/CodeGen/BPF/BTF/variant-part.ll diff --git a/llvm/lib/Target/BPF/BTFDebug.cpp b/llvm/lib/Target/BPF/BTFDebug.cpp index 1e29a0f1e85a1..4ec7a93891aef 100644 --- a/llvm/lib/Target/BPF/BTFDebug.cpp +++ b/llvm/lib/Target/BPF/BTFDebug.cpp @@ -14,6 +14,7 @@ #include "BPF.h" #include "BPFCORE.h" #include "MCTargetDesc/BPFMCTargetDesc.h" +#include "llvm/BinaryFormat/Dwarf.h" #include "llvm/BinaryFormat/ELF.h" #include "llvm/CodeGen/AsmPrinter.h" #include "llvm/CodeGen/MachineModuleInfo.h" @@ -23,6 +24,7 @@ #include "llvm/MC/MCObjectFileInfo.h" #include "llvm/MC/MCSectionELF.h" #include "llvm/MC/MCStreamer.h" +#include "llvm/Support/ErrorHandling.h" #include "llvm/Support/LineIterator.h" #include "llvm/Support/MemoryBuffer.h" #include "llvm/Target/TargetLoweringObjectFile.h" @@ -301,21 +303,59 @@ void BTFTypeStruct::completeType(BTFDebug &BDebug) { BTFType.NameOff = BDebug.addString(STy->getName()); + if (STy->getTag() == dwarf::DW_TAG_variant_part) { + // Variant parts might have a discriminator, which has its own memory + // location, and variants, which share the memory location afterwards. LLVM + // DI doesn't consider discriminator as an element and instead keeps + // it as a separate reference. + // To keep BTF simple, let's represent the structure as an union with + // discriminator as the first element. + // The offsets inside variant types are already handled correctly in the + // DI. + const auto *DTy = STy->getDiscriminator(); + if (DTy) { + struct BTF::BTFMember Discriminator; + + Discriminator.NameOff = BDebug.addString(DTy->getName()); + Discriminator.Offset = DTy->getOffsetInBits(); + const auto *BaseTy = DTy->getBaseType(); + Discriminator.Type = BDebug.getTypeId(BaseTy); + + Members.push_back(Discriminator); + } + } + // Add struct/union members. const DINodeArray Elements = STy->getElements(); for (const auto *Element : Elements) { struct BTF::BTFMember BTFMember; - const auto *DDTy = cast<DIDerivedType>(Element); - BTFMember.NameOff = BDebug.addString(DDTy->getName()); - if (HasBitField) { - uint8_t BitFieldSize = DDTy->isBitField() ? DDTy->getSizeInBits() : 0; - BTFMember.Offset = BitFieldSize << 24 | DDTy->getOffsetInBits(); - } else { - BTFMember.Offset = DDTy->getOffsetInBits(); + switch (Element->getTag()) { + case dwarf::DW_TAG_member: { + const auto *DDTy = cast<DIDerivedType>(Element); + + BTFMember.NameOff = BDebug.addString(DDTy->getName()); + if (HasBitField) { + uint8_t BitFieldSize = DDTy->isBitField() ? DDTy->getSizeInBits() : 0; + BTFMember.Offset = BitFieldSize << 24 | DDTy->getOffsetInBits(); + } else { + BTFMember.Offset = DDTy->getOffsetInBits(); + } + const auto *BaseTy = tryRemoveAtomicType(DDTy->getBaseType()); + BTFMember.Type = BDebug.getTypeId(BaseTy); + break; + } + case dwarf::DW_TAG_variant_part: { + const auto *DCTy = dyn_cast<DICompositeType>(Element); + + BTFMember.NameOff = BDebug.addString(DCTy->getName()); + BTFMember.Offset = DCTy->getOffsetInBits(); + BTFMember.Type = BDebug.getTypeId(DCTy); + break; + } + default: + llvm_unreachable("Unexpected DI tag of a struct/union element"); } - const auto *BaseTy = tryRemoveAtomicType(DDTy->getBaseType()); - BTFMember.Type = BDebug.getTypeId(BaseTy); Members.push_back(BTFMember); } } @@ -672,16 +712,28 @@ void BTFDebug::visitStructType(const DICompositeType *CTy, bool IsStruct, uint32_t &TypeId) { const DINodeArray Elements = CTy->getElements(); uint32_t VLen = Elements.size(); + // Variant parts might have a discriminator. LLVM DI doesn't consider it as + // an element and instead keeps it as a separate reference. But we represent + // it as an element in BTF. + if (CTy->getTag() == dwarf::DW_TAG_variant_part) { + const auto *DTy = CTy->getDiscriminator(); + if (DTy) { + visitTypeEntry(DTy); + VLen++; + } + } if (VLen > BTF::MAX_VLEN) return; // Check whether we have any bitfield members or not bool HasBitField = false; for (const auto *Element : Elements) { - auto E = cast<DIDerivedType>(Element); - if (E->isBitField()) { - HasBitField = true; - break; + if (Element->getTag() == dwarf::DW_TAG_member) { + auto E = cast<DIDerivedType>(Element); + if (E->isBitField()) { + HasBitField = true; + break; + } } } @@ -696,9 +748,22 @@ void BTFDebug::visitStructType(const DICompositeType *CTy, bool IsStruct, // Visit all struct members. int FieldNo = 0; for (const auto *Element : Elements) { - const auto Elem = cast<DIDerivedType>(Element); - visitTypeEntry(Elem); - processDeclAnnotations(Elem->getAnnotations(), TypeId, FieldNo); + switch (Element->getTag()) { + case dwarf::DW_TAG_member: { + const auto Elem = cast<DIDerivedType>(Element); + visitTypeEntry(Elem); + processDeclAnnotations(Elem->getAnnotations(), TypeId, FieldNo); + break; + } + case dwarf::DW_TAG_variant_part: { + const auto Elem = cast<DICompositeType>(Element); + visitTypeEntry(Elem); + processDeclAnnotations(Elem->getAnnotations(), TypeId, FieldNo); + break; + } + default: + llvm_unreachable("Unexpected DI tag of a struct/union element"); + } FieldNo++; } } @@ -781,16 +846,25 @@ void BTFDebug::visitFwdDeclType(const DICompositeType *CTy, bool IsUnion, void BTFDebug::visitCompositeType(const DICompositeType *CTy, uint32_t &TypeId) { auto Tag = CTy->getTag(); - if (Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type) { + switch (Tag) { + case dwarf::DW_TAG_structure_type: + case dwarf::DW_TAG_union_type: + case dwarf::DW_TAG_variant_part: // Handle forward declaration differently as it does not have members. if (CTy->isForwardDecl()) visitFwdDeclType(CTy, Tag == dwarf::DW_TAG_union_type, TypeId); else visitStructType(CTy, Tag == dwarf::DW_TAG_structure_type, TypeId); - } else if (Tag == dwarf::DW_TAG_array_type) + break; + case dwarf::DW_TAG_array_type: visitArrayType(CTy, TypeId); - else if (Tag == dwarf::DW_TAG_enumeration_type) + break; + case dwarf::DW_TAG_enumeration_type: visitEnumType(CTy, TypeId); + break; + default: + llvm_unreachable("Unexpected DI tag of a composite type"); + } } bool BTFDebug::IsForwardDeclCandidate(const DIType *Base) { diff --git a/llvm/test/CodeGen/BPF/BTF/variant-part.ll b/llvm/test/CodeGen/BPF/BTF/variant-part.ll new file mode 100644 index 0000000000000..1071e618f601b --- /dev/null +++ b/llvm/test/CodeGen/BPF/BTF/variant-part.ll @@ -0,0 +1,87 @@ +; RUN: llc -mtriple=bpfel -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; RUN: llc -mtriple=bpfeb -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; +; Source: +; #![no_std] +; #![no_main] +; +; pub enum MyEnum { +; First { a: u32, b: i32 }, +; Second(u32), +; } +; +; #[unsafe(no_mangle)] +; pub static X: MyEnum = MyEnum::First { a: 54, b: -23 }; +; +; #[cfg(not(test))] +; #[panic_handler] +; fn panic(_info: &core::panic::PanicInfo) -> ! { +; loop {} +; } +; Compilation flag: +; cargo +nightly rustc -Zbuild-std=core --target=bpfel-unknown-none -- --emit=llvm-bc +; llvm-extract --glob=X $(find target/ -name "*.bc" | head -n 1) -o variant-part.bc +; llvm-dis variant-part.bc -o variant-part.ll + +; ModuleID = 'variant-part.bc' +source_filename = "c0znihgkvro8hs0n88fgrtg6x" +target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128" +target triple = "bpfel" + +@X = constant [12 x i8] c"\00\00\00\006\00\00\00\E9\FF\FF\FF", align 4, !dbg !0 + +!llvm.module.flags = !{!22, !23, !24, !25} +!llvm.ident = !{!26} +!llvm.dbg.cu = !{!27} + +; CHECK-BTF: [1] STRUCT 'MyEnum' size=12 vlen=1 +; CHECK-BTF-NEXT: '(anon)' type_id=3 bits_offset=0 +; CHECK-BTF-NEXT: [2] INT 'u32' size=4 bits_offset=0 nr_bits=32 encoding=(none) +; CHECK-BTF-NEXT: [3] UNION '(anon)' size=12 vlen=3 +; CHECK-BTF-NEXT: '(anon)' type_id=2 bits_offset=0 +; CHECK-BTF-NEXT: 'First' type_id=4 bits_offset=0 +; CHECK-BTF-NEXT: 'Second' type_id=6 bits_offset=0 +; CHECK-BTF-NEXT: [4] STRUCT 'First' size=12 vlen=2 +; CHECK-BTF-NEXT: 'a' type_id=2 bits_offset=32 +; CHECK-BTF-NEXT: 'b' type_id=5 bits_offset=64 +; CHECK-BTF-NEXT: [5] INT 'i32' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED +; CHECK-BTF-NEXT: [6] STRUCT 'Second' size=12 vlen=1 +; CHECK-BTF-NEXT: '__0' type_id=2 bits_offset=32 +; CHECK-BTF-NEXT: [7] VAR 'X' type_id=1, linkage=global +; CHECK-BTF-NEXT: [8] DATASEC '.rodata' size=0 vlen=1 +; CHECK-BTF-NEXT: type_id=7 offset=0 size=12 + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "X", scope: !2, file: !3, line: 10, type: !4, isLocal: false, isDefinition: true, align: 32) +!2 = !DINamespace(name: "variant_part", scope: null) +!3 = !DIFile(filename: "variant-part/src/main.rs", directory: "/tmp/variant-part", checksumkind: CSK_MD5, checksum: "b94cd53886ea8f14cbc116b36bc7dd36") +!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "MyEnum", scope: !2, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !6, templateParams: !16, identifier: "faba668fd9f71e9b7cf3b9ac5e8b93cb") +!5 = !DIFile(filename: "<unknown>", directory: "") +!6 = !{!7} +!7 = !DICompositeType(tag: DW_TAG_variant_part, scope: !4, file: !5, size: 96, align: 32, elements: !8, templateParams: !16, identifier: "e4aee046fc86d111657622fdcb8c42f7", discriminator: !21) +!8 = !{!9, !17} +!9 = !DIDerivedType(tag: DW_TAG_member, name: "First", scope: !7, file: !5, baseType: !10, size: 96, align: 32, extraData: i32 0) +!10 = !DICompositeType(tag: DW_TAG_structure_type, name: "First", scope: !4, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !11, templateParams: !16, identifier: "cc7748c842e275452db4205b190c8ff7") +!11 = !{!12, !14} +!12 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !10, file: !5, baseType: !13, size: 32, align: 32, offset: 32, flags: DIFlagPublic) +!13 = !DIBasicType(name: "u32", size: 32, encoding: DW_ATE_unsigned) +!14 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !10, file: !5, baseType: !15, size: 32, align: 32, offset: 64, flags: DIFlagPublic) +!15 = !DIBasicType(name: "i32", size: 32, encoding: DW_ATE_signed) +!16 = !{} +!17 = !DIDerivedType(tag: DW_TAG_member, name: "Second", scope: !7, file: !5, baseType: !18, size: 96, align: 32, extraData: i32 1) +!18 = !DICompositeType(tag: DW_TAG_structure_type, name: "Second", scope: !4, file: !5, size: 96, align: 32, flags: DIFlagPublic, elements: !19, templateParams: !16, identifier: "a2094b1381f3082d504fbd0903aa7c06") +!19 = !{!20} +!20 = !DIDerivedType(tag: DW_TAG_member, name: "__0", scope: !18, file: !5, baseType: !13, size: 32, align: 32, offset: 32, flags: DIFlagPublic) +!21 = !DIDerivedType(tag: DW_TAG_member, scope: !4, file: !5, baseType: !13, size: 32, align: 32, flags: DIFlagArtificial) +!22 = !{i32 8, !"PIC Level", i32 2} +!23 = !{i32 7, !"PIE Level", i32 2} +!24 = !{i32 7, !"Dwarf Version", i32 4} +!25 = !{i32 2, !"Debug Info Version", i32 3} +!26 = !{!"rustc version 1.91.0-nightly (160e7623e 2025-08-26)"} +!27 = distinct !DICompileUnit(language: DW_LANG_Rust, file: !28, producer: "clang LLVM (rustc version 1.91.0-nightly (160e7623e 2025-08-26))", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !29, splitDebugInlining: false, nameTableKind: None) +!28 = !DIFile(filename: "variant-part/src/main.rs/@/c0znihgkvro8hs0n88fgrtg6x", directory: "/tmp/variant-part") +!29 = !{!0} >From c346c16f93d5a3fcb2b1a74501279959878136c6 Mon Sep 17 00:00:00 2001 From: Michal R <[email protected]> Date: Wed, 22 Oct 2025 16:30:33 +0200 Subject: [PATCH 2/2] [BPF] Do not emit names for PTR, CONST, VOLATILE and RESTRICT BTF types (#163174) We currently raise a warning in `print_btf.py` when any of these types have a name. Linux kernel doesn't allow names in these types either.[0] However, there is nothing stopping frontends from giving names to these types. To make sure that they are always anonymous, explicitly skip the name emission. [0] https://elixir.bootlin.com/linux/v6.17.1/source/kernel/bpf/btf.c#L2586 --- llvm/lib/Target/BPF/BTFDebug.cpp | 19 +++++- llvm/test/CodeGen/BPF/BTF/ptr-named-2.ll | 59 +++++++++++++++++++ llvm/test/CodeGen/BPF/BTF/ptr-named.ll | 75 ++++++++++++++++++++++++ 3 files changed, 152 insertions(+), 1 deletion(-) create mode 100644 llvm/test/CodeGen/BPF/BTF/ptr-named-2.ll create mode 100644 llvm/test/CodeGen/BPF/BTF/ptr-named.ll diff --git a/llvm/lib/Target/BPF/BTFDebug.cpp b/llvm/lib/Target/BPF/BTFDebug.cpp index 4ec7a93891aef..9bf14ab59c7c8 100644 --- a/llvm/lib/Target/BPF/BTFDebug.cpp +++ b/llvm/lib/Target/BPF/BTFDebug.cpp @@ -95,7 +95,24 @@ void BTFTypeDerived::completeType(BTFDebug &BDebug) { return; IsCompleted = true; - BTFType.NameOff = BDebug.addString(Name); + switch (Kind) { + case BTF::BTF_KIND_PTR: + case BTF::BTF_KIND_CONST: + case BTF::BTF_KIND_VOLATILE: + case BTF::BTF_KIND_RESTRICT: + // Debug info might contain names for these types, but given that we want + // to keep BTF minimal and naming reference types doesn't bring any value + // (what matters is the completeness of the base type), we don't emit them. + // + // Furthermore, the Linux kernel refuses to load BPF programs that contain + // BTF with these types named: + // https://elixir.bootlin.com/linux/v6.17.1/source/kernel/bpf/btf.c#L2586 + BTFType.NameOff = 0; + break; + default: + BTFType.NameOff = BDebug.addString(Name); + break; + } if (NeedsFixup || !DTy) return; diff --git a/llvm/test/CodeGen/BPF/BTF/ptr-named-2.ll b/llvm/test/CodeGen/BPF/BTF/ptr-named-2.ll new file mode 100644 index 0000000000000..df0cbeb3dd625 --- /dev/null +++ b/llvm/test/CodeGen/BPF/BTF/ptr-named-2.ll @@ -0,0 +1,59 @@ +; RUN: llc -mtriple=bpfel -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; RUN: llc -mtriple=bpfeb -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; +; This IR is hand-written. + +; ModuleID = 'ptr-named-2.ll' +source_filename = "ptr-named-2.ll" +target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128" +target triple = "bpfel-unknown-none" + +%struct.TypeExamples = type { i32*, i32, i32, i32* } + +@type_examples = internal global %struct.TypeExamples zeroinitializer, align 8, !dbg !0 + +!llvm.dbg.cu = !{!1} +!llvm.module.flags = !{!2, !3, !4} +!llvm.ident = !{!21} + +; CHECK-BTF: [1] STRUCT 'TypeExamples' size=32 vlen=4 +; CHECK-BTF-NEXT: 'ptr' type_id=2 bits_offset=0 +; CHECK-BTF-NEXT: 'volatile' type_id=4 bits_offset=64 +; CHECK-BTF-NEXT: 'const' type_id=5 bits_offset=128 +; CHECK-BTF-NEXT: 'restrict_ptr' type_id=6 bits_offset=192 +; CHECK-BTF-NEXT: [2] PTR '(anon)' type_id=3 +; CHECK-BTF-NEXT: [3] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED +; CHECK-BTF-NEXT: [4] VOLATILE '(anon)' type_id=3 +; CHECK-BTF-NEXT: [5] CONST '(anon)' type_id=3 +; CHECK-BTF-NEXT: [6] RESTRICT '(anon)' type_id=7 +; CHECK-BTF-NEXT: [7] PTR '(anon)' type_id=3 +; CHECK-BTF-NEXT: [8] VAR 'type_examples' type_id=1, linkage=static +; CHECK-BTF-NEXT: [9] DATASEC '.bss' size=0 vlen=1 +; CHECK-BTF-NEXT: type_id=8 offset=0 size=24 + +!0 = !DIGlobalVariableExpression(var: !5, expr: !DIExpression()) +!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !6, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !7, globals: !8, splitDebugInlining: false, nameTableKind: None) +!2 = !{i32 2, !"Dwarf Version", i32 4} +!3 = !{i32 2, !"Debug Info Version", i32 3} +!4 = !{i32 1, !"wchar_size", i32 4} +!5 = distinct !DIGlobalVariable(name: "type_examples", scope: !1, file: !6, line: 12, type: !9, isLocal: true, isDefinition: true) +!6 = !DIFile(filename: "ptr-named-2.ll", directory: "/tmp") +!7 = !{} +!8 = !{!0} +!9 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "TypeExamples", file: !6, line: 5, size: 256, elements: !10) +!10 = !{!11, !12, !13, !14} +!11 = !DIDerivedType(tag: DW_TAG_member, name: "ptr", scope: !9, file: !6, line: 6, baseType: !15, size: 64) +!12 = !DIDerivedType(tag: DW_TAG_member, name: "volatile", scope: !9, file: !6, line: 7, baseType: !17, size: 64, offset: 64) +!13 = !DIDerivedType(tag: DW_TAG_member, name: "const", scope: !9, file: !6, line: 8, baseType: !18, size: 64, offset: 128) +!14 = !DIDerivedType(tag: DW_TAG_member, name: "restrict_ptr", scope: !9, file: !6, line: 9, baseType: !19, size: 64, offset: 192) +!15 = !DIDerivedType(tag: DW_TAG_pointer_type, name: "*int", baseType: !16, size: 64) +!16 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!17 = !DIDerivedType(tag: DW_TAG_volatile_type, name: "volatile int", baseType: !16) +!18 = !DIDerivedType(tag: DW_TAG_const_type, name: "const int", baseType: !16) +!19 = !DIDerivedType(tag: DW_TAG_restrict_type, name: "*int restrict", baseType: !20) +!20 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !16, size: 64) +!21 = !{!"my hand-written IR"} diff --git a/llvm/test/CodeGen/BPF/BTF/ptr-named.ll b/llvm/test/CodeGen/BPF/BTF/ptr-named.ll new file mode 100644 index 0000000000000..675c34e976abb --- /dev/null +++ b/llvm/test/CodeGen/BPF/BTF/ptr-named.ll @@ -0,0 +1,75 @@ +; RUN: llc -mtriple=bpfel -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; RUN: llc -mtriple=bpfeb -filetype=obj -o %t1 %s +; RUN: llvm-objcopy --dump-section='.BTF'=%t2 %t1 +; RUN: %python %p/print_btf.py %t2 | FileCheck -check-prefixes=CHECK-BTF %s +; +; Source: +; #![no_std] +; #![no_main] +; +; pub struct MyType { +; ptr: *const u32, +; } +; +; impl MyType { +; pub const fn new() -> Self { +; let ptr = core::ptr::null(); +; Self { ptr } +; } +; } +; +; unsafe impl Sync for MyType {} +; +; #[unsafe(no_mangle)] +; pub static X: MyType = MyType::new(); +; +; #[cfg(not(test))] +; #[panic_handler] +; fn panic(_info: &core::panic::PanicInfo) -> ! { +; loop {} +; } +; Compilation flag: +; cargo +nightly rustc -Zbuild-std=core --target=bpfel-unknown-none -- --emit=llvm-bc +; llvm-extract --glob=X $(find target/ -name "*.bc" | head -n 1) -o ptr-named.bc +; llvm-dis ptr-named.bc -o ptr-named.ll + +; ModuleID = 'ptr-named.bc' +source_filename = "1m2uqe50qkwxmo53ydydvou91" +target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128" +target triple = "bpfel" + +@X = constant [8 x i8] zeroinitializer, align 8, !dbg !0 + +!llvm.module.flags = !{!11, !12, !13, !14} +!llvm.ident = !{!15} +!llvm.dbg.cu = !{!16} + +; CHECK-BTF: [1] STRUCT 'MyType' size=8 vlen=1 +; CHECK-BTF-NEXT: 'ptr' type_id=2 bits_offset=0 +; CHECK-BTF-NEXT: [2] PTR '(anon)' type_id=3 +; CHECK-BTF-NEXT: [3] INT 'u32' size=4 bits_offset=0 nr_bits=32 encoding=(none) +; CHECK-BTF-NEXT: [4] VAR 'X' type_id=1, linkage=global +; CHECK-BTF-NEXT: [5] DATASEC '.rodata' size=0 vlen=1 +; CHECK-BTF-NEXT: type_id=4 offset=0 size=8 + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "X", scope: !2, file: !3, line: 19, type: !4, isLocal: false, isDefinition: true, align: 64) +!2 = !DINamespace(name: "ptr_named", scope: null) +!3 = !DIFile(filename: "ptr-named/src/main.rs", directory: "/tmp/ptr-named", checksumkind: CSK_MD5, checksum: "e37168304600b30cbb5ba168f0384932") +!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "MyType", scope: !2, file: !5, size: 64, align: 64, flags: DIFlagPublic, elements: !6, templateParams: !10, identifier: "7609fa40332dd486922f074276a171c3") +!5 = !DIFile(filename: "<unknown>", directory: "") +!6 = !{!7} +!7 = !DIDerivedType(tag: DW_TAG_member, name: "ptr", scope: !4, file: !5, baseType: !8, size: 64, align: 64, flags: DIFlagPrivate) +!8 = !DIDerivedType(tag: DW_TAG_pointer_type, name: "*const u32", baseType: !9, size: 64, align: 64, dwarfAddressSpace: 0) +!9 = !DIBasicType(name: "u32", size: 32, encoding: DW_ATE_unsigned) +!10 = !{} +!11 = !{i32 8, !"PIC Level", i32 2} +!12 = !{i32 7, !"PIE Level", i32 2} +!13 = !{i32 7, !"Dwarf Version", i32 4} +!14 = !{i32 2, !"Debug Info Version", i32 3} +!15 = !{!"rustc version 1.92.0-nightly (c8905eaa6 2025-09-28)"} +!16 = distinct !DICompileUnit(language: DW_LANG_Rust, file: !17, producer: "clang LLVM (rustc version 1.92.0-nightly (c8905eaa6 2025-09-28))", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !18, splitDebugInlining: false, nameTableKind: None) +!17 = !DIFile(filename: "ptr-named/src/main.rs/@/1m2uqe50qkwxmo53ydydvou91", directory: "/tmp/ptr-named") +!18 = !{!0} _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
