From 3be47f9a7f01b9549048722d8191ab1ff823e919 Mon Sep 17 00:00:00 2001 From: Shivam Gupta Date: Tue, 1 Jul 2025 19:42:48 +0530 Subject: [PATCH] [AArch64] Support TLS variables in debug info This adds an implementation of getDebugThreadLocalSymbol for AArch64 by using AArch::S_DTPREL. Fixes #83466 --- lld/ELF/Arch/AArch64.cpp | 6 +++ .../Plugins/ObjectFile/ELF/ObjectFileELF.cpp | 1 + .../AArch64/AArch64TargetObjectFile.cpp | 7 +++- .../Target/AArch64/AArch64TargetObjectFile.h | 3 ++ .../AArch64/AsmParser/AArch64AsmParser.cpp | 3 ++ .../MCTargetDesc/AArch64ELFObjectWriter.cpp | 5 +++ .../AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp | 2 + llvm/test/CodeGen/AArch64/tls-dtprel64.ll | 37 ++++++++++++++++++ .../test/DebugInfo/AArch64/tls-at-location.ll | 12 ++++-- llvm/test/MC/AArch64/tls-dtprel64.s | 38 +++++++++++++++++++ 10 files changed, 110 insertions(+), 4 deletions(-) create mode 100644 llvm/test/CodeGen/AArch64/tls-dtprel64.ll create mode 100644 llvm/test/MC/AArch64/tls-dtprel64.s diff --git a/lld/ELF/Arch/AArch64.cpp b/lld/ELF/Arch/AArch64.cpp index 1812f2af419d2..7576d904e3a60 100644 --- a/lld/ELF/Arch/AArch64.cpp +++ b/lld/ELF/Arch/AArch64.cpp @@ -156,6 +156,8 @@ RelExpr AArch64::getRelExpr(RelType type, const Symbol &s, return R_ABS; case R_AARCH64_AUTH_ABS64: return RE_AARCH64_AUTH; + case R_AARCH64_TLS_DTPREL64: + return R_DTPREL; case R_AARCH64_TLSDESC_ADR_PAGE21: return RE_AARCH64_TLSDESC_PAGE; case R_AARCH64_AUTH_TLSDESC_ADR_PAGE21: @@ -542,6 +544,10 @@ void AArch64::relocate(uint8_t *loc, const Relocation &rel, if (isInt<32>(val)) write32(ctx, loc, val); break; + case R_AARCH64_TLS_DTPREL64: + checkInt(ctx, loc, val, 64, rel); + write64(ctx, loc, val); + break; case R_AARCH64_ADD_ABS_LO12_NC: case R_AARCH64_AUTH_GOT_ADD_LO12_NC: write32Imm12(loc, val); diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp index f69358de6a288..4593b7253a574 100644 --- a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp +++ b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp @@ -2843,6 +2843,7 @@ unsigned ObjectFileELF::ApplyRelocations( case llvm::ELF::EM_AARCH64: switch (reloc_type(rel)) { case R_AARCH64_ABS64: + case R_AARCH64_TLS_DTPREL64: ApplyELF64ABS64Relocation(symtab, rel, debug_data, rel_section); break; case R_AARCH64_ABS32: diff --git a/llvm/lib/Target/AArch64/AArch64TargetObjectFile.cpp b/llvm/lib/Target/AArch64/AArch64TargetObjectFile.cpp index c218831ce0400..f76103733969a 100644 --- a/llvm/lib/Target/AArch64/AArch64TargetObjectFile.cpp +++ b/llvm/lib/Target/AArch64/AArch64TargetObjectFile.cpp @@ -30,7 +30,7 @@ void AArch64_ELFTargetObjectFile::Initialize(MCContext &Ctx, // AARCH64 ELF ABI does not define static relocation type for TLS offset // within a module. Do not generate AT_location for TLS variables. - SupportDebugThreadLocalLocation = false; + SupportDebugThreadLocalLocation = true; // Make sure the implicitly created empty .text section has the // SHF_AARCH64_PURECODE flag set if the "+execute-only" target feature is @@ -186,3 +186,8 @@ MCSection *AArch64_ELFTargetObjectFile::SelectSectionForGlobal( return TargetLoweringObjectFileELF::SelectSectionForGlobal(GO, Kind, TM); } + +const MCExpr *AArch64_ELFTargetObjectFile::getDebugThreadLocalSymbol( + const MCSymbol *Sym) const { + return MCSymbolRefExpr::create(Sym, AArch64::S_DTPREL, getContext()); +} diff --git a/llvm/lib/Target/AArch64/AArch64TargetObjectFile.h b/llvm/lib/Target/AArch64/AArch64TargetObjectFile.h index 6b3381452c70b..78c0c22da8d1b 100644 --- a/llvm/lib/Target/AArch64/AArch64TargetObjectFile.h +++ b/llvm/lib/Target/AArch64/AArch64TargetObjectFile.h @@ -40,6 +40,9 @@ class AArch64_ELFTargetObjectFile : public TargetLoweringObjectFileELF { MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const override; + + /// Describe a TLS variable address within debug info. + const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const override; }; /// AArch64_MachoTargetObjectFile - This TLOF implementation is used for Darwin. diff --git a/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp b/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp index f16fc6cfefa42..35dc8e6e9902d 100644 --- a/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp +++ b/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp @@ -4421,6 +4421,7 @@ bool AArch64AsmParser::parseSymbolicImmVal(const MCExpr *&ImmVal) { .Case("prel_g1_nc", AArch64::S_PREL_G1_NC) .Case("prel_g0", AArch64::S_PREL_G0) .Case("prel_g0_nc", AArch64::S_PREL_G0_NC) + .Case("dtprel", AArch64::S_DTPREL) .Case("dtprel_g2", AArch64::S_DTPREL_G2) .Case("dtprel_g1", AArch64::S_DTPREL_G1) .Case("dtprel_g1_nc", AArch64::S_DTPREL_G1_NC) @@ -8191,6 +8192,8 @@ bool AArch64AsmParser::parseDataExpr(const MCExpr *&Res) { Spec = AArch64::S_GOTPCREL; else if (Identifier == "plt") Spec = AArch64::S_PLT; + else if (Identifier == "dtprel") + Spec = AArch64::S_DTPREL; } if (Spec == AArch64::S_None) return Error(Loc, "invalid relocation specifier"); diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp index ebd5f30796195..9a9dd369f1ff3 100644 --- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp +++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp @@ -234,6 +234,9 @@ unsigned AArch64ELFObjectWriter::getRelocType(const MCFixup &Fixup, } if (RefKind == AArch64::S_AUTH || RefKind == AArch64::S_AUTHADDR) return ELF::R_AARCH64_AUTH_ABS64; + if (RefKind == AArch64::S_DTPREL) { + return ELF::R_AARCH64_TLS_DTPREL64; + } return ELF::R_AARCH64_ABS64; } case AArch64::fixup_aarch64_add_imm12: @@ -448,6 +451,8 @@ unsigned AArch64ELFObjectWriter::getRelocType(const MCFixup &Fixup, return R_CLS(MOVW_PREL_G0); if (RefKind == AArch64::S_PREL_G0_NC) return R_CLS(MOVW_PREL_G0_NC); + if (RefKind == AArch64::S_DTPREL) + return ELF::R_AARCH64_TLS_DTPREL64; if (RefKind == AArch64::S_DTPREL_G2) return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G2; if (RefKind == AArch64::S_DTPREL_G1) diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp index c08664944f727..01c50d13f1945 100644 --- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp +++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp @@ -41,6 +41,7 @@ const MCAsmInfo::AtSpecifier ELFAtSpecifiers[] = { {AArch64::S_GOT, "GOT"}, {AArch64::S_GOTPCREL, "GOTPCREL"}, {AArch64::S_PLT, "PLT"}, + {AArch64::S_DTPREL, "DTPREL"}, }; const MCAsmInfo::AtSpecifier MachOAtSpecifiers[] = { @@ -76,6 +77,7 @@ StringRef AArch64::getSpecifierName(const MCSpecifierExpr &Expr) { case AArch64::S_PREL_G1_NC: return ":prel_g1_nc:"; case AArch64::S_PREL_G0: return ":prel_g0:"; case AArch64::S_PREL_G0_NC: return ":prel_g0_nc:"; + case AArch64::S_DTPREL: return ":dtprel:"; case AArch64::S_DTPREL_G2: return ":dtprel_g2:"; case AArch64::S_DTPREL_G1: return ":dtprel_g1:"; case AArch64::S_DTPREL_G1_NC: return ":dtprel_g1_nc:"; diff --git a/llvm/test/CodeGen/AArch64/tls-dtprel64.ll b/llvm/test/CodeGen/AArch64/tls-dtprel64.ll new file mode 100644 index 0000000000000..c481980354905 --- /dev/null +++ b/llvm/test/CodeGen/AArch64/tls-dtprel64.ll @@ -0,0 +1,37 @@ +; RUN: llc -O0 -mtriple=aarch64-linux-gnu -filetype=obj < %s \ +; RUN: | llvm-objdump -r - | FileCheck %s + +; CHECK: R_AARCH64_TLS_DTPREL64 + +@var = thread_local global i32 0, align 4, !dbg !0 + +; Function Attrs: noinline nounwind optnone +define i32 @foo() #0 !dbg !11 { +entry: + %0 = load i32, ptr @var, align 4, !dbg !14 + ret i32 %0, !dbg !15 +} + +attributes #0 = { noinline nounwind optnone } + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!7, !8, !9} +!llvm.ident = !{!10} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "var", scope: !2, file: !3, line: 1, type: !6, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 7.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5) +!3 = !DIFile(filename: "tls-at-location.c", directory: "/home/lliu0/llvm/tls-at-location/DebugInfo/AArch64") +!4 = !{} +!5 = !{!0} +!6 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!7 = !{i32 2, !"Dwarf Version", i32 4} +!8 = !{i32 2, !"Debug Info Version", i32 3} +!9 = !{i32 1, !"wchar_size", i32 4} +!10 = !{!"clang version 7.0.0"} +!11 = distinct !DISubprogram(name: "foo", scope: !3, file: !3, line: 3, type: !12, isLocal: false, isDefinition: true, scopeLine: 3, isOptimized: false, unit: !2) +!12 = !DISubroutineType(types: !13) +!13 = !{!6} +!14 = !DILocation(line: 4, column: 10, scope: !11) +!15 = !DILocation(line: 4, column: 3, scope: !11) + diff --git a/llvm/test/DebugInfo/AArch64/tls-at-location.ll b/llvm/test/DebugInfo/AArch64/tls-at-location.ll index 20a0afb789771..d619962ccbf69 100644 --- a/llvm/test/DebugInfo/AArch64/tls-at-location.ll +++ b/llvm/test/DebugInfo/AArch64/tls-at-location.ll @@ -1,8 +1,14 @@ -; RUN: llc -filetype=obj -mtriple=aarch64--linux-gnu -o - %s | llvm-dwarfdump -v - | FileCheck %s -; +; RUN: llc -O0 -mtriple=aarch64-non-linux-gnu -filetype=obj < %s \ +; RUN: | llvm-dwarfdump - | FileCheck %s + ; CHECK: .debug_info contents: ; CHECK: DW_TAG_variable -; CHECK-NOT: DW_AT_location +; CHECK: DW_AT_name ("var") +; CHECK-NEXT: DW_AT_type (0x00000040 "int") +; CHECK-NEXT: DW_AT_external (true) +; CHECK-NEXT: DW_AT_decl_file ("{{.*}}tls-at-location.c") +; CHECK-NEXT: DW_AT_decl_line (1) +; CHECK-NEXT: DW_AT_location (DW_OP_const8u 0x0, DW_OP_GNU_push_tls_address) @var = thread_local global i32 0, align 4, !dbg !0 diff --git a/llvm/test/MC/AArch64/tls-dtprel64.s b/llvm/test/MC/AArch64/tls-dtprel64.s new file mode 100644 index 0000000000000..7cb47f9543f68 --- /dev/null +++ b/llvm/test/MC/AArch64/tls-dtprel64.s @@ -0,0 +1,38 @@ +# RUN: llvm-mc -filetype=obj -triple=aarch64-none-linux-gnu %s | llvm-readobj -r - | FileCheck %s + +# CHECK: Relocations [ +# CHECK: Section {{.*}} .rela.debug_info { +# CHECK: 0x{{[0-9A-F]+}} R_AARCH64_TLS_DTPREL64 var {{.*}} +# CHECK: } + +.section .tdata,"awT",@progbits +.globl var +var: + .word 0 + +.section .debug_abbrev,"",@progbits +.byte 1 // Abbreviation Code +.byte 17 // DW_TAG_compile_unit +.byte 1 // DW_CHILDREN_yes +.byte 0 // EOM(1) +.byte 0 // EOM(2) + +.byte 2 // Abbreviation Code +.byte 52 // DW_TAG_variable +.byte 0 // DW_CHILDREN_no +.byte 2; // DW_AT_location +.byte 24 // DW_FORM_exprloc +.byte 0 // EOM(1) +.byte 0 // EOM(2) + +.section .debug_info,"",@progbits +.Lcu_begin0: + .word .Lcu_end - .Lcu_body // Length of Unit +.Lcu_body: + .hword 4 // DWARF version number + .word .debug_abbrev // Offset Into Abbrev. Section + .byte 8 // Address Size (in bytes) + .byte 1 // Abbrev [1] DW_TAG_compile_unit + .byte 2 // Abbrev [2] DW_TAG_variable + .xword var@DTPREL +.Lcu_end: