From 26935e73bc7cf2fa606e4e099195997713e48f9f Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Tue, 10 Oct 2017 01:49:21 +0000 Subject: [PATCH] [MC] Properly diagnose badly scoped .cfi_ directives Removes two report_fatal_errors. Implement this by removing EmitCFICommon, and do the checking in getCurrentDwarfFrameInfo. Have the callers check for null before dereferencing it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315264 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/MC/MCStreamer.h | 3 - lib/MC/MCStreamer.cpp | 104 +++++++++++++++++++++------------ test/MC/X86/cfi-scope-errors.s | 18 ++++++ 3 files changed, 84 insertions(+), 41 deletions(-) create mode 100644 test/MC/X86/cfi-scope-errors.s diff --git a/include/llvm/MC/MCStreamer.h b/include/llvm/MC/MCStreamer.h index e43bc608f0b..8f7189bfc1b 100644 --- a/include/llvm/MC/MCStreamer.h +++ b/include/llvm/MC/MCStreamer.h @@ -171,9 +171,6 @@ class MCStreamer { std::vector DwarfFrameInfos; MCDwarfFrameInfo *getCurrentDwarfFrameInfo(); - void EnsureValidDwarfFrame(); - - MCSymbol *EmitCFICommon(); /// Similar to DwarfFrameInfos, but for SEH unwind info. Chained frames may /// refer to each other, so use std::unique_ptr to provide pointer stability. diff --git a/lib/MC/MCStreamer.cpp b/lib/MC/MCStreamer.cpp index d414c01fa16..4067df0eaf5 100644 --- a/lib/MC/MCStreamer.cpp +++ b/lib/MC/MCStreamer.cpp @@ -206,21 +206,18 @@ MCSymbol *MCStreamer::getDwarfLineTableSymbol(unsigned CUID) { return Table.getLabel(); } -MCDwarfFrameInfo *MCStreamer::getCurrentDwarfFrameInfo() { - if (DwarfFrameInfos.empty()) - return nullptr; - return &DwarfFrameInfos.back(); -} - bool MCStreamer::hasUnfinishedDwarfFrameInfo() { - MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); - return CurFrame && !CurFrame->End; + return !DwarfFrameInfos.empty() && !DwarfFrameInfos.back().End; } -void MCStreamer::EnsureValidDwarfFrame() { - MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); - if (!CurFrame || CurFrame->End) - report_fatal_error("No open frame"); +MCDwarfFrameInfo *MCStreamer::getCurrentDwarfFrameInfo() { + if (!hasUnfinishedDwarfFrameInfo()) { + getContext().reportError(SMLoc(), "this directive must appear between " + ".cfi_startproc and .cfi_endproc " + "directives"); + return nullptr; + } + return &DwarfFrameInfos.back(); } bool MCStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename, @@ -324,7 +321,8 @@ void MCStreamer::EmitCFISections(bool EH, bool Debug) { void MCStreamer::EmitCFIStartProc(bool IsSimple) { if (hasUnfinishedDwarfFrameInfo()) - report_fatal_error("Starting a frame before finishing the previous one!"); + getContext().reportError( + SMLoc(), "starting new .cfi frame before finishing the previous one"); MCDwarfFrameInfo Frame; Frame.IsSimple = IsSimple; @@ -347,8 +345,9 @@ void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { } void MCStreamer::EmitCFIEndProc() { - EnsureValidDwarfFrame(); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; EmitCFIEndProcImpl(*CurFrame); } @@ -364,155 +363,184 @@ MCSymbol *MCStreamer::EmitCFILabel() { return (MCSymbol *)1; } -MCSymbol *MCStreamer::EmitCFICommon() { - EnsureValidDwarfFrame(); - return EmitCFILabel(); -} - void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfa(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); CurFrame->CurrentCfaRegister = static_cast(Register); } void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfaOffset(Label, Offset); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfaRegister(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); CurFrame->CurrentCfaRegister = static_cast(Register); } void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createOffset(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createRelOffset(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding) { - EnsureValidDwarfFrame(); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Personality = Sym; CurFrame->PersonalityEncoding = Encoding; } void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) { - EnsureValidDwarfFrame(); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Lsda = Sym; CurFrame->LsdaEncoding = Encoding; } void MCStreamer::EmitCFIRememberState() { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRestoreState() { // FIXME: Error if there is no matching cfi_remember_state. - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFISameValue(int64_t Register) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createSameValue(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRestore(int64_t Register) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createRestore(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIEscape(StringRef Values) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIGnuArgsSize(int64_t Size) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createGnuArgsSize(Label, Size); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFISignalFrame() { - EnsureValidDwarfFrame(); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->IsSignalFrame = true; } void MCStreamer::EmitCFIUndefined(int64_t Register) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createUndefined(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createRegister(Label, Register1, Register2); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIWindowSave() { - MCSymbol *Label = EmitCFICommon(); + MCSymbol *Label = EmitCFILabel(); MCCFIInstruction Instruction = MCCFIInstruction::createWindowSave(Label); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIReturnColumn(int64_t Register) { - EnsureValidDwarfFrame(); MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo(); + if (!CurFrame) + return; CurFrame->RAReg = Register; } diff --git a/test/MC/X86/cfi-scope-errors.s b/test/MC/X86/cfi-scope-errors.s new file mode 100644 index 00000000000..a61f817f741 --- /dev/null +++ b/test/MC/X86/cfi-scope-errors.s @@ -0,0 +1,18 @@ +# RUN: not llvm-mc %s -triple x86_64-linux -o /dev/null 2>&1 | FileCheck %s --implicit-check-not=error: + +# FIXME: Push source locations into diagnostics. + +.text +.cfi_def_cfa rsp, 8 +# CHECK: error: this directive must appear between .cfi_startproc and .cfi_endproc directives + +.cfi_startproc +nop + +.cfi_startproc +# CHECK: error: starting new .cfi frame before finishing the previous one +nop +.cfi_endproc + +.cfi_def_cfa rsp, 8 +# CHECK: error: this directive must appear between .cfi_startproc and .cfi_endproc directives -- 2.40.0