From be886690bd4c770483b3adf4268c0baf3d58cea7 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Mon, 9 Mar 2015 18:29:12 +0000 Subject: [PATCH] Print jump tables before exception tables. In the case where just tables are part of the function section, this produces more readable assembly by avoiding switching to the eh section and back to .text. This would also break with non unique section names, as trying to switch to a unique section actually creates a new one. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231677 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/AsmPrinter/ARMException.cpp | 11 ++----- lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 19 ++++++++----- lib/CodeGen/AsmPrinter/AsmPrinterHandler.h | 4 +++ lib/CodeGen/AsmPrinter/DwarfCFIException.cpp | 30 +++++++++++++------- lib/CodeGen/AsmPrinter/DwarfException.h | 17 +++++++---- test/CodeGen/X86/global-sections.ll | 8 ++++-- 6 files changed, 54 insertions(+), 35 deletions(-) diff --git a/lib/CodeGen/AsmPrinter/ARMException.cpp b/lib/CodeGen/AsmPrinter/ARMException.cpp index 119aa3a18c4..3cde13e3fad 100644 --- a/lib/CodeGen/AsmPrinter/ARMException.cpp +++ b/lib/CodeGen/AsmPrinter/ARMException.cpp @@ -36,8 +36,7 @@ #include "llvm/Target/TargetRegisterInfo.h" using namespace llvm; -ARMException::ARMException(AsmPrinter *A) - : EHStreamer(A), shouldEmitCFI(false) {} +ARMException::ARMException(AsmPrinter *A) : DwarfCFIExceptionBase(A) {} ARMException::~ARMException() {} @@ -70,13 +69,7 @@ void ARMException::beginFunction(const MachineFunction *MF) { /// endFunction - Gather and emit post-function exception information. /// -void ARMException::endFunction(const MachineFunction *) { - if (shouldEmitCFI) - Asm->OutStreamer.EmitCFIEndProc(); - - // Map all labels and get rid of any dead landing pads. - MMI->TidyLandingPads(); - +void ARMException::endFunction(const MachineFunction *MF) { ARMTargetStreamer &ATS = getTargetStreamer(); if (!Asm->MF->getFunction()->needsUnwindTableEntry() && MMI->getLandingPads().empty()) diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp index 6938ed15765..dbad7a2cebe 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp +++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp @@ -900,6 +900,14 @@ void AsmPrinter::EmitFunctionBody() { OutStreamer.EmitELFSize(CurrentFnSym, SizeExp); } + for (const HandlerInfo &HI : Handlers) { + NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled); + HI.Handler->markFunctionEnd(); + } + + // Print out jump tables referenced by the function. + EmitJumpTableInfo(); + // Emit post-function debug and/or EH information. for (const HandlerInfo &HI : Handlers) { NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled); @@ -907,9 +915,6 @@ void AsmPrinter::EmitFunctionBody() { } MMI->EndFunction(); - // Print out jump tables referenced by the function. - EmitJumpTableInfo(); - OutStreamer.AddBlankLine(); } @@ -1245,10 +1250,8 @@ void AsmPrinter::EmitJumpTableInfo() { bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection( MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32, *F); - if (!JTInDiffSection) { - OutStreamer.SwitchSection(TLOF.SectionForGlobal(F, *Mang, TM)); - } else { - // Otherwise, drop it in the readonly section. + if (JTInDiffSection) { + // Drop it in the readonly section. const MCSection *ReadOnlySection = TLOF.getSectionForJumpTable(*F, *Mang, TM); OutStreamer.SwitchSection(ReadOnlySection); @@ -2504,3 +2507,5 @@ GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) { /// Pin vtable to this file. AsmPrinterHandler::~AsmPrinterHandler() {} + +void AsmPrinterHandler::markFunctionEnd() {} diff --git a/lib/CodeGen/AsmPrinter/AsmPrinterHandler.h b/lib/CodeGen/AsmPrinter/AsmPrinterHandler.h index 31867dd01d0..f1efe9d835e 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinterHandler.h +++ b/lib/CodeGen/AsmPrinter/AsmPrinterHandler.h @@ -41,6 +41,10 @@ public: /// call. virtual void beginFunction(const MachineFunction *MF) = 0; + // \brief Emit any of function marker (like .cfi_endproc). This is called + // before endFunction and cannot switch sections. + virtual void markFunctionEnd(); + /// \brief Gather post-function debug information. /// Please note that some AsmPrinter implementations may not call /// beginFunction at all. diff --git a/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp b/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp index 128ec82995b..0631592c080 100644 --- a/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp @@ -39,9 +39,24 @@ #include "llvm/Target/TargetRegisterInfo.h" using namespace llvm; +DwarfCFIExceptionBase::DwarfCFIExceptionBase(AsmPrinter *A) + : EHStreamer(A), shouldEmitCFI(false) {} + +void DwarfCFIExceptionBase::markFunctionEnd() { + if (shouldEmitCFI) + Asm->OutStreamer.EmitCFIEndProc(); + + if (MMI->getLandingPads().empty()) + return; + + // Map all labels and get rid of any dead landing pads. + MMI->TidyLandingPads(); +} + DwarfCFIException::DwarfCFIException(AsmPrinter *A) - : EHStreamer(A), shouldEmitPersonality(false), shouldEmitLSDA(false), - shouldEmitMoves(false), moveTypeModule(AsmPrinter::CFI_M_None) {} + : DwarfCFIExceptionBase(A), shouldEmitPersonality(false), + shouldEmitLSDA(false), shouldEmitMoves(false), + moveTypeModule(AsmPrinter::CFI_M_None) {} DwarfCFIException::~DwarfCFIException() {} @@ -100,7 +115,8 @@ void DwarfCFIException::beginFunction(const MachineFunction *MF) { shouldEmitLSDA = shouldEmitPersonality && LSDAEncoding != dwarf::DW_EH_PE_omit; - if (!shouldEmitPersonality && !shouldEmitMoves) + shouldEmitCFI = shouldEmitPersonality || shouldEmitMoves; + if (!shouldEmitCFI) return; Asm->OutStreamer.EmitCFIStartProc(/*IsSimple=*/false); @@ -125,16 +141,8 @@ void DwarfCFIException::beginFunction(const MachineFunction *MF) { /// endFunction - Gather and emit post-function exception information. /// void DwarfCFIException::endFunction(const MachineFunction *) { - if (!shouldEmitPersonality && !shouldEmitMoves) - return; - - Asm->OutStreamer.EmitCFIEndProc(); - if (!shouldEmitPersonality) return; - // Map all labels and get rid of any dead landing pads. - MMI->TidyLandingPads(); - emitExceptionTable(); } diff --git a/lib/CodeGen/AsmPrinter/DwarfException.h b/lib/CodeGen/AsmPrinter/DwarfException.h index 115869dc4ed..6eaf7074629 100644 --- a/lib/CodeGen/AsmPrinter/DwarfException.h +++ b/lib/CodeGen/AsmPrinter/DwarfException.h @@ -21,7 +21,17 @@ namespace llvm { class MachineFunction; class ARMTargetStreamer; -class DwarfCFIException : public EHStreamer { +class DwarfCFIExceptionBase : public EHStreamer { +protected: + DwarfCFIExceptionBase(AsmPrinter *A); + + /// Per-function flag to indicate if frame CFI info should be emitted. + bool shouldEmitCFI; + + void markFunctionEnd() override; +}; + +class DwarfCFIException : public DwarfCFIExceptionBase { /// Per-function flag to indicate if .cfi_personality should be emitted. bool shouldEmitPersonality; @@ -51,13 +61,10 @@ public: void endFunction(const MachineFunction *) override; }; -class ARMException : public EHStreamer { +class ARMException : public DwarfCFIExceptionBase { void emitTypeInfos(unsigned TTypeEncoding) override; ARMTargetStreamer &getTargetStreamer(); - /// Per-function flag to indicate if frame CFI info should be emitted. - bool shouldEmitCFI; - public: //===--------------------------------------------------------------------===// // Main entry points. diff --git a/test/CodeGen/X86/global-sections.ll b/test/CodeGen/X86/global-sections.ll index 54c4b1a6f53..cd42f99b771 100644 --- a/test/CodeGen/X86/global-sections.ll +++ b/test/CodeGen/X86/global-sections.ll @@ -86,11 +86,13 @@ bb7: ; DARWIN64: _F3: ; DARWIN64: Lfunc_end ; DARWIN64-NEXT: .cfi_endproc -; DARWIN64-NEXT: .section __TEXT,__gcc_except_tab -; DARWIN64-NOT: .section -; DARWIN64: .section __TEXT,__text,regular,pure_instructions ; DARWIN64-NOT: .section ; DARWIN64: LJTI{{.*}}: +; DARWIN64-NEXT: .long +; DARWIN64-NEXT: .long +; DARWIN64-NEXT: .long +; DARWIN64-NEXT: .long +; DARWIN64-NEXT: .section __TEXT,__gcc_except_tab ; int G1; @G1 = common global i32 0