diff --git a/llvm/include/llvm/MC/MCObjectStreamer.h b/llvm/include/llvm/MC/MCObjectStreamer.h index 0866ff5a9fc0..71354477b331 100644 --- a/llvm/include/llvm/MC/MCObjectStreamer.h +++ b/llvm/include/llvm/MC/MCObjectStreamer.h @@ -41,7 +41,8 @@ class MCObjectStreamer : public MCStreamer { SmallVector PendingLabels; virtual void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo&) = 0; - void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override; + void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, + MCSymbol *FuncSym) override; void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override; // If any labels have been emitted but not assigned fragments, ensure that diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h index 5cded5cfff90..7303bc9dc6c9 100644 --- a/llvm/include/llvm/MC/MCStreamer.h +++ b/llvm/include/llvm/MC/MCStreamer.h @@ -198,7 +198,7 @@ class MCStreamer { protected: MCStreamer(MCContext &Ctx); - virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame); + virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, MCSymbol *FuncSym); virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame); WinEH::FrameInfo *getCurrentWinFrameInfo() { @@ -661,7 +661,7 @@ public: virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID); virtual void EmitCFISections(bool EH, bool Debug); - void EmitCFIStartProc(bool IsSimple); + void EmitCFIStartProc(bool IsSimple, MCSymbol *FuncSym); void EmitCFIEndProc(); virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset); virtual void EmitCFIDefCfaOffset(int64_t Offset); diff --git a/llvm/lib/CodeGen/AsmPrinter/ARMException.cpp b/llvm/lib/CodeGen/AsmPrinter/ARMException.cpp index 251f5effd6b4..e79ede9a5ae8 100644 --- a/llvm/lib/CodeGen/AsmPrinter/ARMException.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/ARMException.cpp @@ -66,7 +66,7 @@ void ARMException::beginFunction(const MachineFunction *MF) { "non-EH CFI not yet supported in prologue with EHABI lowering"); if (MoveType == AsmPrinter::CFI_M_Debug) { shouldEmitCFI = true; - Asm->OutStreamer.EmitCFIStartProc(false); + Asm->OutStreamer.EmitCFIStartProc(false, Asm->CurrentFnSym); } } diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp index 74215aa695dd..b8051fee9fa8 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp @@ -102,7 +102,7 @@ void DwarfCFIException::beginFunction(const MachineFunction *MF) { if (!shouldEmitPersonality && !shouldEmitMoves) return; - Asm->OutStreamer.EmitCFIStartProc(/*IsSimple=*/false); + Asm->OutStreamer.EmitCFIStartProc(/*IsSimple=*/false, Asm->CurrentFnSym); // Indicate personality routine, if any. if (!shouldEmitPersonality) diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp index f60c7fc50415..9e100333e9bf 100644 --- a/llvm/lib/MC/MCAsmStreamer.cpp +++ b/llvm/lib/MC/MCAsmStreamer.cpp @@ -54,7 +54,8 @@ private: unsigned UseDwarfDirectory : 1; void EmitRegisterName(int64_t Register); - void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override; + void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, + MCSymbol *FuncSym) override; void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override; public: @@ -925,7 +926,8 @@ void MCAsmStreamer::EmitCFISections(bool EH, bool Debug) { EmitEOL(); } -void MCAsmStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { +void MCAsmStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, + MCSymbol *FuncSym) { OS << "\t.cfi_startproc"; if (Frame.IsSimple) OS << " simple"; diff --git a/llvm/lib/MC/MCObjectStreamer.cpp b/llvm/lib/MC/MCObjectStreamer.cpp index 21e68678e75b..17371a285089 100644 --- a/llvm/lib/MC/MCObjectStreamer.cpp +++ b/llvm/lib/MC/MCObjectStreamer.cpp @@ -128,10 +128,13 @@ void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, DF->getContents().resize(DF->getContents().size() + Size, 0); } -void MCObjectStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { - // We need to create a local symbol to avoid relocations. - Frame.Begin = getContext().CreateTempSymbol(); - EmitLabel(Frame.Begin); +void MCObjectStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, + MCSymbol *FuncSym) { + if (!FuncSym) { + FuncSym = getContext().CreateTempSymbol(); + EmitLabel(FuncSym); + } + Frame.Begin = FuncSym; } void MCObjectStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) { diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp index de7d96129f18..5a56094a3c75 100644 --- a/llvm/lib/MC/MCParser/AsmParser.cpp +++ b/llvm/lib/MC/MCParser/AsmParser.cpp @@ -172,6 +172,9 @@ private: /// \brief Are we parsing ms-style inline assembly? bool ParsingInlineAsm; + /// \brief The last symbol we emitted, used for call frame information. + MCSymbol *LastFuncSymbol; + public: AsmParser(SourceMgr &SM, MCContext &Ctx, MCStreamer &Out, const MCAsmInfo &MAI); @@ -491,7 +494,8 @@ AsmParser::AsmParser(SourceMgr &_SM, MCContext &_Ctx, MCStreamer &_Out, : Lexer(_MAI), Ctx(_Ctx), Out(_Out), MAI(_MAI), SrcMgr(_SM), PlatformParser(nullptr), CurBuffer(_SM.getMainFileID()), MacrosEnabledFlag(true), HadError(false), CppHashLineNumber(0), - AssemblerDialect(~0U), IsDarwin(false), ParsingInlineAsm(false) { + AssemblerDialect(~0U), IsDarwin(false), ParsingInlineAsm(false), + LastFuncSymbol(nullptr) { // Save the old handler. SavedDiagHandler = SrcMgr.getDiagHandler(); SavedDiagContext = SrcMgr.getDiagContext(); @@ -1305,6 +1309,9 @@ bool AsmParser::parseStatement(ParseStatementInfo &Info, if (!ParsingInlineAsm) Out.EmitLabel(Sym); + // Record the symbol, so that it can be used for call frame information + LastFuncSymbol = Sym; + // If we are generating dwarf for assembly source files then gather the // info to make a dwarf label entry for this label if needed. if (getContext().getGenDwarfForAssembly()) @@ -2961,7 +2968,7 @@ bool AsmParser::parseDirectiveCFIStartProc() { if (parseIdentifier(Simple) || Simple != "simple") return TokError("unexpected token in .cfi_startproc directive"); - getStreamer().EmitCFIStartProc(!Simple.empty()); + getStreamer().EmitCFIStartProc(!Simple.empty(), LastFuncSymbol); return false; } diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp index f11ee669b4b6..23e816c24bf8 100644 --- a/llvm/lib/MC/MCStreamer.cpp +++ b/llvm/lib/MC/MCStreamer.cpp @@ -211,14 +211,14 @@ void MCStreamer::EmitCFISections(bool EH, bool Debug) { assert(EH || Debug); } -void MCStreamer::EmitCFIStartProc(bool IsSimple) { +void MCStreamer::EmitCFIStartProc(bool IsSimple, MCSymbol *FuncSym) { MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); if (CurFrame && !CurFrame->End) report_fatal_error("Starting a frame before finishing the previous one!"); MCDwarfFrameInfo Frame; Frame.IsSimple = IsSimple; - EmitCFIStartProcImpl(Frame); + EmitCFIStartProcImpl(Frame, FuncSym); const MCAsmInfo* MAI = Context.getAsmInfo(); if (MAI) { @@ -233,8 +233,8 @@ void MCStreamer::EmitCFIStartProc(bool IsSimple) { DwarfFrameInfos.push_back(Frame); } -void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { -} +void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame, + MCSymbol *FuncSym) {} void MCStreamer::EmitCFIEndProc() { EnsureValidDwarfFrame(); diff --git a/llvm/test/DebugInfo/AArch64/eh_frame.s b/llvm/test/DebugInfo/AArch64/eh_frame.s index 12a58961d717..75b036eac26b 100644 --- a/llvm/test/DebugInfo/AArch64/eh_frame.s +++ b/llvm/test/DebugInfo/AArch64/eh_frame.s @@ -1,5 +1,6 @@ // RUN: llvm-mc -triple aarch64-none-linux-gnu -filetype=obj %s -o %t -// RUN: llvm-objdump -s %t | FileCheck %s +// RUN: llvm-objdump -s %t | FileCheck %s --check-prefix=CHECK +// RUN: llvm-readobj -r %t | FileCheck %s --check-prefix=RELOC .text .globl foo .type foo,@function @@ -46,3 +47,11 @@ foo: // 00000000: PC begin for this FDE is at 00000000 (relocation is applied here) // 04000000: FDE applies up to PC begin+0x14 // 00: Augmentation string length 0 for this FDE + + +// Check the relocations applied to the .eh_frame section. +// These must not contain section-relative relocations to a section which +// is part of a group, as it could be removed. +// RELOC: Section ({{[0-9]+}}) .rela.eh_frame { +// RELOC-NEXT: 0x{{[0-9A-F]+}} R_AARCH64_PREL32 foo 0x0 +// RELOC-NEXT: } diff --git a/llvm/test/DebugInfo/AArch64/eh_frame_personality.ll b/llvm/test/DebugInfo/AArch64/eh_frame_personality.ll index 51d6bf80b950..0cc53a810e97 100644 --- a/llvm/test/DebugInfo/AArch64/eh_frame_personality.ll +++ b/llvm/test/DebugInfo/AArch64/eh_frame_personality.ll @@ -1,5 +1,6 @@ ; RUN: llc -verify-machineinstrs -mtriple=aarch64-none-linux-gnu %s -filetype=obj -o %t -; RUN: llvm-objdump -s %t | FileCheck %s +; RUN: llvm-objdump -s %t | FileCheck %s --check-prefix=CHECK +; RUN: llvm-readobj -r %t | FileCheck %s --check-prefix=RELOC declare i32 @__gxx_personality_v0(...) @@ -44,3 +45,12 @@ clean: ; 00: Second part of aug (language-specific data): absolute pointer format used ; 1b: pointer format: pc-relative signed 4-byte. Just like GNU. ; 0c 1f 00: Initial instructions ("DW_CFA_def_cfa x31 ofs 0" in this case) + +; Check the relocations applied to the .eh_frame section. +; These must not contain section-relative relocations to a section which +; is part of a group, as it could be removed. +; RELOC: Section ({{[0-9]+}}) .rela.eh_frame { +; RELOC-NEXT: 0x{{[0-9A-F]+}} R_AARCH64_ABS64 __gxx_personality_v0 0x0 +; RELOC-NEXT: 0x{{[0-9A-F]+}} R_AARCH64_PREL32 foo 0x0 +; RELOC-NEXT: 0x{{[0-9A-F]+}} R_AARCH64_ABS64 .gcc_except_table 0x0 +; RELOC-NEXT: }