- // Indicate locations of general callee saved registers in frame.
- std::vector<MachineMove> Moves;
- RI->getInitialFrameState(Moves);
- EmitFrameMoves(0, Moves, true);
-
- // On Darwin the linker honors the alignment of eh_frame, which means it must
- // be 8-byte on 64-bit targets to match what gcc does. Otherwise you get
- // holes which confuse readers of eh_frame.
- Asm->EmitAlignment(TD->getPointerSize() == 4 ? 2 : 3, 0, 0, false);
- Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_common_end", Index));
-}
-
-/// EmitFDE - Emit the Frame Description Entry (FDE) for the function.
-void DwarfException::EmitFDE(const FunctionEHFrameInfo &EHFrameInfo) {
- assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() &&
- "Should not emit 'available externally' functions at all");
-
- const Function *TheFunc = EHFrameInfo.function;
- const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
-
- unsigned LSDAEncoding = TLOF.getLSDAEncoding();
- unsigned FDEEncoding = TLOF.getFDEEncoding();
-
- Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
-
- // Externally visible entry into the functions eh frame info. If the
- // corresponding function is static, this should not be externally visible.
- if (!TheFunc->hasLocalLinkage() && TLOF.isFunctionEHSymbolGlobal())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,MCSA_Global);
-
- // If corresponding function is weak definition, this should be too.
- if (TheFunc->isWeakForLinker() && MAI->getWeakDefDirective())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- MCSA_WeakDefinition);
-
- // If corresponding function is hidden, this should be too.
- if (TheFunc->hasHiddenVisibility())
- if (MCSymbolAttr HiddenAttr = MAI->getHiddenVisibilityAttr())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- HiddenAttr);
-
- // If there are no calls then you can't unwind. This may mean we can omit the
- // EH Frame, but some environments do not handle weak absolute symbols. If
- // UnwindTablesMandatory is set we cannot do this optimization; the unwind
- // info is to be available for non-EH uses.
- if (!EHFrameInfo.hasCalls && !UnwindTablesMandatory &&
- (!TheFunc->isWeakForLinker() ||
- !MAI->getWeakDefDirective() ||
- TLOF.getSupportsWeakOmittedEHFrame())) {
- Asm->OutStreamer.EmitAssignment(EHFrameInfo.FunctionEHSym,
- MCConstantExpr::Create(0, Asm->OutContext));
- // This name has no connection to the function, so it might get
- // dead-stripped when the function is not, erroneously. Prohibit
- // dead-stripping unconditionally.
- if (MAI->hasNoDeadStrip())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- MCSA_NoDeadStrip);
- } else {
- Asm->OutStreamer.EmitLabel(EHFrameInfo.FunctionEHSym);
-
- // EH frame header.
- Asm->OutStreamer.AddComment("Length of Frame Information Entry");
- EmitDifference(getDWLabel("eh_frame_end", EHFrameInfo.Number),
- getDWLabel("eh_frame_begin", EHFrameInfo.Number),
- true);
-
- Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_begin",EHFrameInfo.Number));
-
- Asm->OutStreamer.AddComment("FDE CIE offset");
- EmitSectionOffset(getDWLabel("eh_frame_begin", EHFrameInfo.Number),
- getDWLabel("eh_frame_common",
- EHFrameInfo.PersonalityIndex),
- true, true);
-
- MCSymbol *EHFuncBeginSym = getDWLabel("eh_func_begin", EHFrameInfo.Number);
-
- Asm->OutStreamer.AddComment("FDE initial location");
- EmitReference(EHFuncBeginSym, FDEEncoding);
-
- Asm->OutStreamer.AddComment("FDE address range");
- EmitDifference(getDWLabel("eh_func_end", EHFrameInfo.Number),EHFuncBeginSym,
- SizeOfEncodedValue(FDEEncoding) == 4);
-
- // If there is a personality and landing pads then point to the language
- // specific data area in the exception table.
- if (MMI->getPersonalities()[0] != NULL) {
- unsigned Size = SizeOfEncodedValue(LSDAEncoding);
-
- EmitULEB128(Size, "Augmentation size");
- Asm->OutStreamer.AddComment("Language Specific Data Area");
- if (EHFrameInfo.hasLandingPads)
- EmitReference(getDWLabel("exception", EHFrameInfo.Number),LSDAEncoding);
- else
- Asm->OutStreamer.EmitIntValue(0, Size/*size*/, 0/*addrspace*/);
-
- } else {
- EmitULEB128(0, "Augmentation size");
- }
-
- // Indicate locations of function specific callee saved registers in frame.
- EmitFrameMoves(EHFuncBeginSym, EHFrameInfo.Moves, true);
-
- // On Darwin the linker honors the alignment of eh_frame, which means it
- // must be 8-byte on 64-bit targets to match what gcc does. Otherwise you
- // get holes which confuse readers of eh_frame.
- Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
- 0, 0, false);
- Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_end", EHFrameInfo.Number));
-
- // If the function is marked used, this table should be also. We cannot
- // make the mark unconditional in this case, since retaining the table also
- // retains the function in this case, and there is code around that depends
- // on unused functions (calling undefined externals) being dead-stripped to
- // link correctly. Yes, there really is.
- if (MMI->isUsedFunction(EHFrameInfo.function))
- if (MAI->hasNoDeadStrip())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- MCSA_NoDeadStrip);
- }
- Asm->OutStreamer.AddBlankLine();
-}