DwarfException.cpp revision 73c5a6172508e957d0b1a46170cb070dce6cac4f
1eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling//===-- CodeGen/AsmPrinter/DwarfException.cpp - Dwarf Exception Impl ------===// 2eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// 3eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// The LLVM Compiler Infrastructure 4eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// 5eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// This file is distributed under the University of Illinois Open Source 6eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// License. See LICENSE.TXT for details. 7eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// 8eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling//===----------------------------------------------------------------------===// 9eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// 1028275fdf02885587156da5cb20388b22d5b96557Bill Wendling// This file contains support for writing DWARF exception info into asm files. 11eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling// 12eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling//===----------------------------------------------------------------------===// 13eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 14eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "DwarfException.h" 15eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/Module.h" 16eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/CodeGen/MachineModuleInfo.h" 17eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/CodeGen/MachineFrameInfo.h" 18fc4da0cea8a0f6c9c1483b92c2dffda217c0ba24David Greene#include "llvm/CodeGen/MachineFunction.h" 19eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/CodeGen/MachineLocation.h" 2043e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling#include "llvm/MC/MCSection.h" 216c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner#include "llvm/MC/MCStreamer.h" 22af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner#include "llvm/MC/MCAsmInfo.h" 23eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/Target/TargetData.h" 24eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/Target/TargetFrameInfo.h" 25d5bbb07ec806e6fa1e804afd7073987fdacc83e4Chris Lattner#include "llvm/Target/TargetLoweringObjectFile.h" 26eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/Target/TargetOptions.h" 27d5bbb07ec806e6fa1e804afd7073987fdacc83e4Chris Lattner#include "llvm/Target/TargetRegisterInfo.h" 286c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner#include "llvm/Support/Dwarf.h" 293fb2b1ede30193b59a651328a946174196b20610Jim Grosbach#include "llvm/Support/Mangler.h" 306c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner#include "llvm/Support/Timer.h" 316c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner#include "llvm/Support/raw_ostream.h" 32c40d9f9bae70c83947bf8fa5f9ee97adbf1bb0c0Jim Grosbach#include "llvm/ADT/SmallString.h" 33eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling#include "llvm/ADT/StringExtras.h" 34eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingusing namespace llvm; 35eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 36eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingstatic TimerGroup &getDwarfTimerGroup() { 3728275fdf02885587156da5cb20388b22d5b96557Bill Wendling static TimerGroup DwarfTimerGroup("DWARF Exception"); 38eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling return DwarfTimerGroup; 39eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 40eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 41bc0d23afae781c45f92865c1c27bed0ce51fe545Bill WendlingDwarfException::DwarfException(raw_ostream &OS, AsmPrinter *A, 42af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner const MCAsmInfo *T) 43bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling : Dwarf(OS, A, T, "eh"), shouldEmitTable(false), shouldEmitMoves(false), 44bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling shouldEmitTableModule(false), shouldEmitMovesModule(false), 45bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling ExceptionTimer(0) { 46dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher if (TimePassesIsEnabled) 4728275fdf02885587156da5cb20388b22d5b96557Bill Wendling ExceptionTimer = new Timer("DWARF Exception Writer", 48bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling getDwarfTimerGroup()); 49bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling} 50bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling 51bc0d23afae781c45f92865c1c27bed0ce51fe545Bill WendlingDwarfException::~DwarfException() { 52bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling delete ExceptionTimer; 53bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling} 54bc0d23afae781c45f92865c1c27bed0ce51fe545Bill Wendling 55bb3e29932d14cc012149a1ab452b88e6f6f5bb49Bill Wendling/// SizeOfEncodedValue - Return the size of the encoding in bytes. 5652783c63a13d384582997684384553e6545852d3Bill Wendlingunsigned DwarfException::SizeOfEncodedValue(unsigned Encoding) { 5752783c63a13d384582997684384553e6545852d3Bill Wendling if (Encoding == dwarf::DW_EH_PE_omit) 5852783c63a13d384582997684384553e6545852d3Bill Wendling return 0; 5952783c63a13d384582997684384553e6545852d3Bill Wendling 6052783c63a13d384582997684384553e6545852d3Bill Wendling switch (Encoding & 0x07) { 6152783c63a13d384582997684384553e6545852d3Bill Wendling case dwarf::DW_EH_PE_absptr: 6252783c63a13d384582997684384553e6545852d3Bill Wendling return TD->getPointerSize(); 6352783c63a13d384582997684384553e6545852d3Bill Wendling case dwarf::DW_EH_PE_udata2: 6452783c63a13d384582997684384553e6545852d3Bill Wendling return 2; 6552783c63a13d384582997684384553e6545852d3Bill Wendling case dwarf::DW_EH_PE_udata4: 6652783c63a13d384582997684384553e6545852d3Bill Wendling return 4; 6752783c63a13d384582997684384553e6545852d3Bill Wendling case dwarf::DW_EH_PE_udata8: 6852783c63a13d384582997684384553e6545852d3Bill Wendling return 8; 6952783c63a13d384582997684384553e6545852d3Bill Wendling } 7052783c63a13d384582997684384553e6545852d3Bill Wendling 7128275fdf02885587156da5cb20388b22d5b96557Bill Wendling assert(0 && "Invalid encoded value."); 7252783c63a13d384582997684384553e6545852d3Bill Wendling return 0; 7352783c63a13d384582997684384553e6545852d3Bill Wendling} 7452783c63a13d384582997684384553e6545852d3Bill Wendling 757ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendling/// EmitCIE - Emit a Common Information Entry (CIE). This holds information that 767ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendling/// is shared among many Frame Description Entries. There is at least one CIE 777ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendling/// in every non-empty .debug_frame section. 787ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendlingvoid DwarfException::EmitCIE(const Function *Personality, unsigned Index) { 79eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Size and sign of stack growth. 80eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling int stackGrowth = 81eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->TM.getFrameInfo()->getStackGrowthDirection() == 82eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling TargetFrameInfo::StackGrowsUp ? 83eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling TD->getPointerSize() : -TD->getPointerSize(); 84eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 85eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Begin eh frame section. 866c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getEHFrameSection()); 87eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 8833adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (MAI->is_EHSymbolPrivate()) 8933adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner O << MAI->getPrivateGlobalPrefix(); 90eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 91eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << "EH_frame" << Index << ":\n"; 92eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("section_eh_frame", Index); 93eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 94eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Define base labels. 95eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("eh_frame_common", Index); 96eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 97eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Define the eh frame length. 98eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitDifference("eh_frame_common_end", Index, 99eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling "eh_frame_common_begin", Index, true); 100eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Length of Common Information Entry"); 101eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 102eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // EH frame header. 103eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("eh_frame_common_begin", Index); 104eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitInt32((int)0); 105eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Identifier Tag"); 106eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitInt8(dwarf::DW_CIE_VERSION); 107eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Version"); 108eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 109eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // The personality presence indicates that language specific information will 110eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // show up in the eh frame. 11152783c63a13d384582997684384553e6545852d3Bill Wendling 11252783c63a13d384582997684384553e6545852d3Bill Wendling // FIXME: Don't hardcode these encodings. 11352783c63a13d384582997684384553e6545852d3Bill Wendling unsigned PerEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 11452783c63a13d384582997684384553e6545852d3Bill Wendling if (Personality && MAI->getNeedsIndirectEncoding()) 11552783c63a13d384582997684384553e6545852d3Bill Wendling PerEncoding |= dwarf::DW_EH_PE_indirect; 11652783c63a13d384582997684384553e6545852d3Bill Wendling unsigned LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 11752783c63a13d384582997684384553e6545852d3Bill Wendling unsigned FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 11852783c63a13d384582997684384553e6545852d3Bill Wendling 11952783c63a13d384582997684384553e6545852d3Bill Wendling char Augmentation[5] = { 0 }; 12052783c63a13d384582997684384553e6545852d3Bill Wendling unsigned AugmentationSize = 0; 12152783c63a13d384582997684384553e6545852d3Bill Wendling char *APtr = Augmentation + 1; 12252783c63a13d384582997684384553e6545852d3Bill Wendling 12352783c63a13d384582997684384553e6545852d3Bill Wendling if (Personality) { 12452783c63a13d384582997684384553e6545852d3Bill Wendling // There is a personality function. 12552783c63a13d384582997684384553e6545852d3Bill Wendling *APtr++ = 'P'; 12652783c63a13d384582997684384553e6545852d3Bill Wendling AugmentationSize += 1 + SizeOfEncodedValue(PerEncoding); 12752783c63a13d384582997684384553e6545852d3Bill Wendling } 12852783c63a13d384582997684384553e6545852d3Bill Wendling 12952783c63a13d384582997684384553e6545852d3Bill Wendling if (UsesLSDA[Index]) { 13052783c63a13d384582997684384553e6545852d3Bill Wendling // An LSDA pointer is in the FDE augmentation. 13152783c63a13d384582997684384553e6545852d3Bill Wendling *APtr++ = 'L'; 13252783c63a13d384582997684384553e6545852d3Bill Wendling ++AugmentationSize; 13352783c63a13d384582997684384553e6545852d3Bill Wendling } 13452783c63a13d384582997684384553e6545852d3Bill Wendling 13552783c63a13d384582997684384553e6545852d3Bill Wendling if (FDEEncoding != dwarf::DW_EH_PE_absptr) { 13652783c63a13d384582997684384553e6545852d3Bill Wendling // A non-default pointer encoding for the FDE. 13752783c63a13d384582997684384553e6545852d3Bill Wendling *APtr++ = 'R'; 13852783c63a13d384582997684384553e6545852d3Bill Wendling ++AugmentationSize; 13952783c63a13d384582997684384553e6545852d3Bill Wendling } 14052783c63a13d384582997684384553e6545852d3Bill Wendling 14152783c63a13d384582997684384553e6545852d3Bill Wendling if (APtr != Augmentation + 1) 14252783c63a13d384582997684384553e6545852d3Bill Wendling Augmentation[0] = 'z'; 14352783c63a13d384582997684384553e6545852d3Bill Wendling 14452783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitString(Augmentation); 145eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Augmentation"); 146eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 147eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Round out reader. 148eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitULEB128Bytes(1); 149eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Code Alignment Factor"); 150eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitSLEB128Bytes(stackGrowth); 151eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Data Alignment Factor"); 152eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true)); 153eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("CIE Return Address Column"); 154eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 15552783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitULEB128Bytes(AugmentationSize); 15652783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EOL("Augmentation Size"); 15752783c63a13d384582997684384553e6545852d3Bill Wendling 15852783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitInt8(PerEncoding); 15952783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EOL("Personality", PerEncoding); 16052783c63a13d384582997684384553e6545852d3Bill Wendling 1614bda11fbdafc1d4fa97b7539bdf5a0f62ecfc280Bill Wendling // If there is a personality, we need to indicate the function's location. 162eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (Personality) { 163eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PrintRelDirective(true); 16433adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner O << MAI->getPersonalityPrefix(); 165eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitExternalGlobal((const GlobalVariable *)(Personality)); 16633adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner O << MAI->getPersonalitySuffix(); 16733adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (strcmp(MAI->getPersonalitySuffix(), "+4@GOTPCREL")) 16833adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner O << "-" << MAI->getPCSymbol(); 169eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Personality"); 170eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 17152783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitInt8(LSDAEncoding); 17252783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EOL("LSDA Encoding", LSDAEncoding); 173eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 17452783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitInt8(FDEEncoding); 17552783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EOL("FDE Encoding", FDEEncoding); 176eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 177eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 178eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Indicate locations of general callee saved registers in frame. 179eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling std::vector<MachineMove> Moves; 180eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling RI->getInitialFrameState(Moves); 181eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitFrameMoves(NULL, 0, Moves, true); 182eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 183eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // On Darwin the linker honors the alignment of eh_frame, which means it must 184eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // be 8-byte on 64-bit targets to match what gcc does. Otherwise you get 185eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // holes which confuse readers of eh_frame. 186eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3, 187eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 0, 0, false); 188eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("eh_frame_common_end", Index); 189eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 190eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL(); 191eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 192eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 1937ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendling/// EmitFDE - Emit the Frame Description Entry (FDE) for the function. 1947ccda0f2aadb601ce48f05c12cc153f3fcc554e6Bill Wendlingvoid DwarfException::EmitFDE(const FunctionEHFrameInfo &EHFrameInfo) { 195dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() && 196eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling "Should not emit 'available externally' functions at all"); 197eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 1983e0f60be46cb5363d4375f26a5e27d1dcd9867fbChris Lattner const Function *TheFunc = EHFrameInfo.function; 199dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher 2006c2f9e14fdf14d8c1c687c6bd9918183fa7f8a7fChris Lattner Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getEHFrameSection()); 201dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher 202eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Externally visible entry into the functions eh frame info. If the 203eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // corresponding function is static, this should not be externally visible. 2043e0f60be46cb5363d4375f26a5e27d1dcd9867fbChris Lattner if (!TheFunc->hasLocalLinkage()) 20533adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (const char *GlobalEHDirective = MAI->getGlobalEHDirective()) 206eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << GlobalEHDirective << EHFrameInfo.FnName << "\n"; 207eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 208eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // If corresponding function is weak definition, this should be too. 20933adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (TheFunc->isWeakForLinker() && MAI->getWeakDefDirective()) 21033adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner O << MAI->getWeakDefDirective() << EHFrameInfo.FnName << "\n"; 211eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 212eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // If there are no calls then you can't unwind. This may mean we can omit the 213eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // EH Frame, but some environments do not handle weak absolute symbols. If 214eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // UnwindTablesMandatory is set we cannot do this optimization; the unwind 215eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // info is to be available for non-EH uses. 2163e0f60be46cb5363d4375f26a5e27d1dcd9867fbChris Lattner if (!EHFrameInfo.hasCalls && !UnwindTablesMandatory && 2173e0f60be46cb5363d4375f26a5e27d1dcd9867fbChris Lattner (!TheFunc->isWeakForLinker() || 21833adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner !MAI->getWeakDefDirective() || 21933adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner MAI->getSupportsWeakOmittedEHFrame())) { 220eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << EHFrameInfo.FnName << " = 0\n"; 221eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // This name has no connection to the function, so it might get 222eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // dead-stripped when the function is not, erroneously. Prohibit 223eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // dead-stripping unconditionally. 22433adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (const char *UsedDirective = MAI->getUsedDirective()) 225eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << UsedDirective << EHFrameInfo.FnName << "\n\n"; 226eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } else { 227eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << EHFrameInfo.FnName << ":\n"; 228eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 229eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // EH frame header. 230eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitDifference("eh_frame_end", EHFrameInfo.Number, 231eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling "eh_frame_begin", EHFrameInfo.Number, true); 232eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Length of Frame Information Entry"); 233eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 234eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("eh_frame_begin", EHFrameInfo.Number); 235eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 236a4ff5e48fc6a4718d3a2af8654cfc06a17310aedChris Lattner EmitSectionOffset("eh_frame_begin", "eh_frame_common", 237a4ff5e48fc6a4718d3a2af8654cfc06a17310aedChris Lattner EHFrameInfo.Number, EHFrameInfo.PersonalityIndex, 238a4ff5e48fc6a4718d3a2af8654cfc06a17310aedChris Lattner true, true, false); 239eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 240eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("FDE CIE offset"); 241eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 242c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands EmitReference("eh_func_begin", EHFrameInfo.Number, true, true); 243eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("FDE initial location"); 244eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitDifference("eh_func_end", EHFrameInfo.Number, 245c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands "eh_func_begin", EHFrameInfo.Number, true); 246eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("FDE address range"); 247eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 248eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // If there is a personality and landing pads then point to the language 249eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // specific data area in the exception table. 250d44fff7849034fc17d6a0e9f9926542865bb7881Eric Christopher if (MMI->getPersonalities()[0] != NULL) { 251c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands bool is4Byte = TD->getPointerSize() == sizeof(int32_t); 252c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands 2536fefcebc4f92b944664b7b26042bc21e57aefe43Eric Christopher Asm->EmitULEB128Bytes(is4Byte ? 4 : 8); 254eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Augmentation size"); 255eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 256c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands if (EHFrameInfo.hasLandingPads) 2576fefcebc4f92b944664b7b26042bc21e57aefe43Eric Christopher EmitReference("exception", EHFrameInfo.Number, true, false); 258c69d74a5d41a6c5e92f9d947f2fa181f48626ca5Duncan Sands else { 25952783c63a13d384582997684384553e6545852d3Bill Wendling if (is4Byte) 26052783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitInt32((int)0); 26152783c63a13d384582997684384553e6545852d3Bill Wendling else 26252783c63a13d384582997684384553e6545852d3Bill Wendling Asm->EmitInt64((int)0); 2636fefcebc4f92b944664b7b26042bc21e57aefe43Eric Christopher } 264eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Language Specific Data Area"); 265eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } else { 266eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitULEB128Bytes(0); 267eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Augmentation size"); 268eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 269eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 270eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Indicate locations of function specific callee saved registers in frame. 271dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher EmitFrameMoves("eh_func_begin", EHFrameInfo.Number, EHFrameInfo.Moves, 272eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling true); 273eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 274eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // On Darwin the linker honors the alignment of eh_frame, which means it 275eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // must be 8-byte on 64-bit targets to match what gcc does. Otherwise you 276eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // get holes which confuse readers of eh_frame. 277eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3, 278eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 0, 0, false); 279eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling EmitLabel("eh_frame_end", EHFrameInfo.Number); 280eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 281eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // If the function is marked used, this table should be also. We cannot 282eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // make the mark unconditional in this case, since retaining the table also 283eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // retains the function in this case, and there is code around that depends 284eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // on unused functions (calling undefined externals) being dead-stripped to 285eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // link correctly. Yes, there really is. 286401e10c4fbfcdcfade5065093e2ca97f69a1d144Chris Lattner if (MMI->isUsedFunction(EHFrameInfo.function)) 28733adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (const char *UsedDirective = MAI->getUsedDirective()) 288eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << UsedDirective << EHFrameInfo.FnName << "\n\n"; 289eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 2904bda11fbdafc1d4fa97b7539bdf5a0f62ecfc280Bill Wendling 2914bda11fbdafc1d4fa97b7539bdf5a0f62ecfc280Bill Wendling Asm->EOL(); 292eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 293eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 294eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// SharedTypeIds - How many leading type ids two landing pads have in common. 295eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingunsigned DwarfException::SharedTypeIds(const LandingPadInfo *L, 296eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling const LandingPadInfo *R) { 297eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds; 298eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned LSize = LIds.size(), RSize = RIds.size(); 299eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned MinSize = LSize < RSize ? LSize : RSize; 300eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned Count = 0; 301eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 302eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling for (; Count != MinSize; ++Count) 303eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (LIds[Count] != RIds[Count]) 304eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling return Count; 305eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 306eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling return Count; 307eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 308eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 309eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// PadLT - Order landing pads lexicographically by type id. 310eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingbool DwarfException::PadLT(const LandingPadInfo *L, const LandingPadInfo *R) { 311eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds; 312eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned LSize = LIds.size(), RSize = RIds.size(); 313eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned MinSize = LSize < RSize ? LSize : RSize; 314eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 315eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling for (unsigned i = 0; i != MinSize; ++i) 316eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (LIds[i] != RIds[i]) 317eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling return LIds[i] < RIds[i]; 318eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 319eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling return LSize < RSize; 320eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 321eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 322d4609622ade8d0ebaf57fd70700c2fedf0b3d165Bill Wendling/// ComputeActionsTable - Compute the actions table and gather the first action 323d4609622ade8d0ebaf57fd70700c2fedf0b3d165Bill Wendling/// index for each landing pad site. 324ade025c65c12503aba161a4fa399fd97414abaffBill Wendlingunsigned DwarfException:: 325ade025c65c12503aba161a4fa399fd97414abaffBill WendlingComputeActionsTable(const SmallVectorImpl<const LandingPadInfo*> &LandingPads, 326ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVectorImpl<ActionEntry> &Actions, 327ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVectorImpl<unsigned> &FirstActions) { 328a583c55864e83e470333b7be878280b10e175a6eBill Wendling 329a583c55864e83e470333b7be878280b10e175a6eBill Wendling // The action table follows the call-site table in the LSDA. The individual 330a583c55864e83e470333b7be878280b10e175a6eBill Wendling // records are of two types: 331a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 332a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * Catch clause 333a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * Exception specification 334a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 335a583c55864e83e470333b7be878280b10e175a6eBill Wendling // The two record kinds have the same format, with only small differences. 336a583c55864e83e470333b7be878280b10e175a6eBill Wendling // They are distinguished by the "switch value" field: Catch clauses 337a583c55864e83e470333b7be878280b10e175a6eBill Wendling // (TypeInfos) have strictly positive switch values, and exception 338a583c55864e83e470333b7be878280b10e175a6eBill Wendling // specifications (FilterIds) have strictly negative switch values. Value 0 339a583c55864e83e470333b7be878280b10e175a6eBill Wendling // indicates a catch-all clause. 340a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 3415e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // Negative type IDs index into FilterIds. Positive type IDs index into 3425e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // TypeInfos. The value written for a positive type ID is just the type ID 3435e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // itself. For a negative type ID, however, the value written is the 344eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // (negative) byte offset of the corresponding FilterIds entry. The byte 3455e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // offset is usually equal to the type ID (because the FilterIds entries are 3465e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // written using a variable width encoding, which outputs one byte per entry 3475e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // as long as the value written is not too large) but can differ. This kind 3485e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling // of complication does not occur for positive type IDs because type infos are 349eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // output using a fixed width encoding. FilterOffsets[i] holds the byte 350eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // offset corresponding to FilterIds[i]. 351409914b773ffd53d53d214394d5636a76f673186Bill Wendling 352409914b773ffd53d53d214394d5636a76f673186Bill Wendling const std::vector<unsigned> &FilterIds = MMI->getFilterIds(); 353eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SmallVector<int, 16> FilterOffsets; 354eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling FilterOffsets.reserve(FilterIds.size()); 355eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling int Offset = -1; 356409914b773ffd53d53d214394d5636a76f673186Bill Wendling 357409914b773ffd53d53d214394d5636a76f673186Bill Wendling for (std::vector<unsigned>::const_iterator 358409914b773ffd53d53d214394d5636a76f673186Bill Wendling I = FilterIds.begin(), E = FilterIds.end(); I != E; ++I) { 359eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling FilterOffsets.push_back(Offset); 360af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner Offset -= MCAsmInfo::getULEB128Size(*I); 361eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 362eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 363eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling FirstActions.reserve(LandingPads.size()); 364eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 365eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling int FirstAction = 0; 366eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned SizeActions = 0; 3675e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling const LandingPadInfo *PrevLPI = 0; 368409914b773ffd53d53d214394d5636a76f673186Bill Wendling 3695cff487665097d971067cbede1598e249f673182Bill Wendling for (SmallVectorImpl<const LandingPadInfo *>::const_iterator 3705e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling I = LandingPads.begin(), E = LandingPads.end(); I != E; ++I) { 3715e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling const LandingPadInfo *LPI = *I; 3725e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling const std::vector<int> &TypeIds = LPI->TypeIds; 3735e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling const unsigned NumShared = PrevLPI ? SharedTypeIds(LPI, PrevLPI) : 0; 374eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned SizeSiteActions = 0; 375eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 376eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (NumShared < TypeIds.size()) { 377eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned SizeAction = 0; 378eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ActionEntry *PrevAction = 0; 379eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 380eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (NumShared) { 3815e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling const unsigned SizePrevIds = PrevLPI->TypeIds.size(); 382eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling assert(Actions.size()); 383eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PrevAction = &Actions.back(); 384af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) + 385af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID); 386eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 387eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling for (unsigned j = NumShared; j != SizePrevIds; ++j) { 388eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SizeAction -= 389af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID); 390eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SizeAction += -PrevAction->NextAction; 391eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PrevAction = PrevAction->Previous; 392eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 393eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 394eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 395eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Compute the actions. 3965e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling for (unsigned J = NumShared, M = TypeIds.size(); J != M; ++J) { 3975e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling int TypeID = TypeIds[J]; 3985e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling assert(-1 - TypeID < (int)FilterOffsets.size() && "Unknown filter id!"); 399eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID; 400af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner unsigned SizeTypeID = MCAsmInfo::getSLEB128Size(ValueForTypeID); 401eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 402eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0; 403af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction); 404eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SizeSiteActions += SizeAction; 405eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 406a583c55864e83e470333b7be878280b10e175a6eBill Wendling ActionEntry Action = { ValueForTypeID, NextAction, PrevAction }; 407eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Actions.push_back(Action); 408eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PrevAction = &Actions.back(); 409eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 410eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 411eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Record the first action of the landing pad site. 412eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling FirstAction = SizeActions + SizeSiteActions - SizeAction + 1; 413eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } // else identical - re-use previous FirstAction 414eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 415a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Information used when created the call-site table. The action record 416a583c55864e83e470333b7be878280b10e175a6eBill Wendling // field of the call site record is the offset of the first associated 417a583c55864e83e470333b7be878280b10e175a6eBill Wendling // action record, relative to the start of the actions table. This value is 418a583c55864e83e470333b7be878280b10e175a6eBill Wendling // biased by 1 (1 in dicating the start of the actions table), and 0 419a583c55864e83e470333b7be878280b10e175a6eBill Wendling // indicates that there are no actions. 420eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling FirstActions.push_back(FirstAction); 421eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 422eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Compute this sites contribution to size. 423eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SizeActions += SizeSiteActions; 4245e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling 4255e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling PrevLPI = LPI; 426eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 427eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 4285e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling return SizeActions; 4295e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling} 4305e953ddfa3abdd684c8a43f9c9c144f584ec7d6fBill Wendling 431ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// ComputeCallSiteTable - Compute the call-site table. The entry for an invoke 432a583c55864e83e470333b7be878280b10e175a6eBill Wendling/// has a try-range containing the call, a non-zero landing pad, and an 433ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// appropriate action. The entry for an ordinary call has a try-range 434ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// containing the call and zero for the landing pad and the action. Calls 435ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// marked 'nounwind' have no entry and must not be contained in the try-range 436ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// of any entry - they form gaps in the table. Entries must be ordered by 437ade025c65c12503aba161a4fa399fd97414abaffBill Wendling/// try-range address. 438ade025c65c12503aba161a4fa399fd97414abaffBill Wendlingvoid DwarfException:: 439ade025c65c12503aba161a4fa399fd97414abaffBill WendlingComputeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites, 440ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const RangeMapType &PadMap, 441ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const SmallVectorImpl<const LandingPadInfo *> &LandingPads, 442ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const SmallVectorImpl<unsigned> &FirstActions) { 443eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // The end label of the previous invoke or nounwind try-range. 444eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned LastLabel = 0; 445eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 446eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Whether there is a potentially throwing instruction (currently this means 447eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // an ordinary call) between the end of the previous try-range and now. 448eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling bool SawPotentiallyThrowing = false; 449eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 4505cff487665097d971067cbede1598e249f673182Bill Wendling // Whether the last CallSite entry was for an invoke. 451eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling bool PreviousIsInvoke = false; 452eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 453eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Visit all instructions in order of address. 454eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 455eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling I != E; ++I) { 456eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end(); 457eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling MI != E; ++MI) { 458eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (!MI->isLabel()) { 459eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SawPotentiallyThrowing |= MI->getDesc().isCall(); 460eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling continue; 461eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 462eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 463eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling unsigned BeginLabel = MI->getOperand(0).getImm(); 464eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling assert(BeginLabel && "Invalid label!"); 465eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 466eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // End of the previous try-range? 467eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (BeginLabel == LastLabel) 468eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling SawPotentiallyThrowing = false; 469eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 470eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Beginning of a new try-range? 471eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling RangeMapType::iterator L = PadMap.find(BeginLabel); 472eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (L == PadMap.end()) 473eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Nope, it was just some random label. 474eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling continue; 475eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 476a583c55864e83e470333b7be878280b10e175a6eBill Wendling const PadRange &P = L->second; 477eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling const LandingPadInfo *LandingPad = LandingPads[P.PadIndex]; 478eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] && 479eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling "Inconsistent landing pad map!"); 480eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 481a583c55864e83e470333b7be878280b10e175a6eBill Wendling // For Dwarf exception handling (SjLj handling doesn't use this). If some 482a583c55864e83e470333b7be878280b10e175a6eBill Wendling // instruction between the previous try-range and this one may throw, 483a583c55864e83e470333b7be878280b10e175a6eBill Wendling // create a call-site entry with no landing pad for the region between the 484a583c55864e83e470333b7be878280b10e175a6eBill Wendling // try-ranges. 4851b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach if (SawPotentiallyThrowing && 48633adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) { 487a583c55864e83e470333b7be878280b10e175a6eBill Wendling CallSiteEntry Site = { LastLabel, BeginLabel, 0, 0 }; 488eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling CallSites.push_back(Site); 489eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PreviousIsInvoke = false; 490eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 491eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 492eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling LastLabel = LandingPad->EndLabels[P.RangeIndex]; 493eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling assert(BeginLabel && LastLabel && "Invalid landing pad!"); 494eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 495eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (LandingPad->LandingPadLabel) { 496eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // This try-range is for an invoke. 497a583c55864e83e470333b7be878280b10e175a6eBill Wendling CallSiteEntry Site = { 498a583c55864e83e470333b7be878280b10e175a6eBill Wendling BeginLabel, 499a583c55864e83e470333b7be878280b10e175a6eBill Wendling LastLabel, 500a583c55864e83e470333b7be878280b10e175a6eBill Wendling LandingPad->LandingPadLabel, 501a583c55864e83e470333b7be878280b10e175a6eBill Wendling FirstActions[P.PadIndex] 502a583c55864e83e470333b7be878280b10e175a6eBill Wendling }; 503eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 50433668c0f1a7e374d4c3c53df34efbdf570e0987bJim Grosbach // Try to merge with the previous call-site. SJLJ doesn't do this 50533668c0f1a7e374d4c3c53df34efbdf570e0987bJim Grosbach if (PreviousIsInvoke && 50633668c0f1a7e374d4c3c53df34efbdf570e0987bJim Grosbach MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) { 507eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling CallSiteEntry &Prev = CallSites.back(); 508eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) { 509eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Extend the range of the previous entry. 510eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Prev.EndLabel = Site.EndLabel; 511eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling continue; 512eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 513eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 514eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 515eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Otherwise, create a new call-site. 516eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling CallSites.push_back(Site); 517eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PreviousIsInvoke = true; 518eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } else { 519eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Create a gap. 520eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PreviousIsInvoke = false; 521eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 522eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 523eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 524eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 525eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // If some instruction between the previous try-range and the end of the 526eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // function may throw, create a call-site entry with no landing pad for the 527eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // region following the try-range. 5281b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach if (SawPotentiallyThrowing && 52933adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) { 530a583c55864e83e470333b7be878280b10e175a6eBill Wendling CallSiteEntry Site = { LastLabel, 0, 0, 0 }; 531eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling CallSites.push_back(Site); 532eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 533ade025c65c12503aba161a4fa399fd97414abaffBill Wendling} 534ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 5350dafca90761097230f02e655fdd541f59b888315Bill Wendling/// EmitExceptionTable - Emit landing pads and actions. 5360dafca90761097230f02e655fdd541f59b888315Bill Wendling/// 5370dafca90761097230f02e655fdd541f59b888315Bill Wendling/// The general organization of the table is complex, but the basic concepts are 5380dafca90761097230f02e655fdd541f59b888315Bill Wendling/// easy. First there is a header which describes the location and organization 5390dafca90761097230f02e655fdd541f59b888315Bill Wendling/// of the three components that follow. 540dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher/// 5410dafca90761097230f02e655fdd541f59b888315Bill Wendling/// 1. The landing pad site information describes the range of code covered by 5420dafca90761097230f02e655fdd541f59b888315Bill Wendling/// the try. In our case it's an accumulation of the ranges covered by the 5430dafca90761097230f02e655fdd541f59b888315Bill Wendling/// invokes in the try. There is also a reference to the landing pad that 5440dafca90761097230f02e655fdd541f59b888315Bill Wendling/// handles the exception once processed. Finally an index into the actions 5450dafca90761097230f02e655fdd541f59b888315Bill Wendling/// table. 546a583c55864e83e470333b7be878280b10e175a6eBill Wendling/// 2. The action table, in our case, is composed of pairs of type IDs and next 5470dafca90761097230f02e655fdd541f59b888315Bill Wendling/// action offset. Starting with the action index from the landing pad 548a583c55864e83e470333b7be878280b10e175a6eBill Wendling/// site, each type ID is checked for a match to the current exception. If 5490dafca90761097230f02e655fdd541f59b888315Bill Wendling/// it matches then the exception and type id are passed on to the landing 5500dafca90761097230f02e655fdd541f59b888315Bill Wendling/// pad. Otherwise the next action is looked up. This chain is terminated 55128275fdf02885587156da5cb20388b22d5b96557Bill Wendling/// with a next action of zero. If no type id is found then the frame is 5520dafca90761097230f02e655fdd541f59b888315Bill Wendling/// unwound and handling continues. 553a583c55864e83e470333b7be878280b10e175a6eBill Wendling/// 3. Type ID table contains references to all the C++ typeinfo for all 55428275fdf02885587156da5cb20388b22d5b96557Bill Wendling/// catches in the function. This tables is reverse indexed base 1. 555ade025c65c12503aba161a4fa399fd97414abaffBill Wendlingvoid DwarfException::EmitExceptionTable() { 556ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos(); 557ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const std::vector<unsigned> &FilterIds = MMI->getFilterIds(); 558ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads(); 559ade025c65c12503aba161a4fa399fd97414abaffBill Wendling if (PadInfos.empty()) return; 560ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 561ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // Sort the landing pads in order of their type ids. This is used to fold 562ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // duplicate actions. 563ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVector<const LandingPadInfo *, 64> LandingPads; 564ade025c65c12503aba161a4fa399fd97414abaffBill Wendling LandingPads.reserve(PadInfos.size()); 565ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 566ade025c65c12503aba161a4fa399fd97414abaffBill Wendling for (unsigned i = 0, N = PadInfos.size(); i != N; ++i) 567ade025c65c12503aba161a4fa399fd97414abaffBill Wendling LandingPads.push_back(&PadInfos[i]); 568ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 569ade025c65c12503aba161a4fa399fd97414abaffBill Wendling std::sort(LandingPads.begin(), LandingPads.end(), PadLT); 570ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 571ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // Compute the actions table and gather the first action index for each 572ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // landing pad site. 573ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVector<ActionEntry, 32> Actions; 574ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVector<unsigned, 64> FirstActions; 57528275fdf02885587156da5cb20388b22d5b96557Bill Wendling unsigned SizeActions = ComputeActionsTable(LandingPads, Actions, 57628275fdf02885587156da5cb20388b22d5b96557Bill Wendling FirstActions); 577ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 578ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // Invokes and nounwind calls have entries in PadMap (due to being bracketed 579ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // by try-range labels when lowered). Ordinary calls do not, so appropriate 58028275fdf02885587156da5cb20388b22d5b96557Bill Wendling // try-ranges for them need be deduced when using DWARF exception handling. 581ade025c65c12503aba161a4fa399fd97414abaffBill Wendling RangeMapType PadMap; 582ade025c65c12503aba161a4fa399fd97414abaffBill Wendling for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) { 583ade025c65c12503aba161a4fa399fd97414abaffBill Wendling const LandingPadInfo *LandingPad = LandingPads[i]; 584ade025c65c12503aba161a4fa399fd97414abaffBill Wendling for (unsigned j = 0, E = LandingPad->BeginLabels.size(); j != E; ++j) { 585ade025c65c12503aba161a4fa399fd97414abaffBill Wendling unsigned BeginLabel = LandingPad->BeginLabels[j]; 586ade025c65c12503aba161a4fa399fd97414abaffBill Wendling assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!"); 587ade025c65c12503aba161a4fa399fd97414abaffBill Wendling PadRange P = { i, j }; 588ade025c65c12503aba161a4fa399fd97414abaffBill Wendling PadMap[BeginLabel] = P; 589ade025c65c12503aba161a4fa399fd97414abaffBill Wendling } 590ade025c65c12503aba161a4fa399fd97414abaffBill Wendling } 591ade025c65c12503aba161a4fa399fd97414abaffBill Wendling 592ade025c65c12503aba161a4fa399fd97414abaffBill Wendling // Compute the call-site table. 593ade025c65c12503aba161a4fa399fd97414abaffBill Wendling SmallVector<CallSiteEntry, 64> CallSites; 5948b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach ComputeCallSiteTable(CallSites, PadMap, LandingPads, FirstActions); 595eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 596eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Final tallies. 597eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 598eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Call sites. 59940121bccbee44d387ab5d6a5194c5fc27c542e12Bill Wendling const unsigned SiteStartSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4); 60040121bccbee44d387ab5d6a5194c5fc27c542e12Bill Wendling const unsigned SiteLengthSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4); 60140121bccbee44d387ab5d6a5194c5fc27c542e12Bill Wendling const unsigned LandingPadSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4); 602d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling bool IsSJLJ = MAI->getExceptionHandlingType() == ExceptionHandling::SjLj; 603d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling bool HaveTTData = IsSJLJ ? (!TypeInfos.empty() || !FilterIds.empty()) : true; 60428275fdf02885587156da5cb20388b22d5b96557Bill Wendling unsigned SizeSites; 605d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling 606d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling if (IsSJLJ) 6078b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach SizeSites = 0; 608d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling else 6091b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach SizeSites = CallSites.size() * 6101b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach (SiteStartSize + SiteLengthSize + LandingPadSize); 611d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling 6121b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach for (unsigned i = 0, e = CallSites.size(); i < e; ++i) { 613af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action); 614d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling if (IsSJLJ) 615af76e592c7f9deff0e55c13dbb4a34f07f1c7f64Chris Lattner SizeSites += MCAsmInfo::getULEB128Size(i); 6161b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } 617d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling 618eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling // Type infos. 619d5bbb07ec806e6fa1e804afd7073987fdacc83e4Chris Lattner const MCSection *LSDASection = Asm->getObjFileLowering().getLSDASection(); 620fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling unsigned TTypeFormat; 621a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling unsigned TypeFormatSize; 622eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 62343e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling if (!HaveTTData) { 62428275fdf02885587156da5cb20388b22d5b96557Bill Wendling // For SjLj exceptions, if there is no TypeInfo, then we just explicitly say 62528275fdf02885587156da5cb20388b22d5b96557Bill Wendling // that we're omitting that bit. 626fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling TTypeFormat = dwarf::DW_EH_PE_omit; 627a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling TypeFormatSize = SizeOfEncodedValue(dwarf::DW_EH_PE_absptr); 62881c9a069377e9474d010f04eebe8325fd11429e3Chris Lattner } else { 629ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // Okay, we have actual filters or typeinfos to emit. As such, we need to 630ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // pick a type encoding for them. We're about to emit a list of pointers to 631ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // typeinfo objects at the end of the LSDA. However, unless we're in static 632ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // mode, this reference will require a relocation by the dynamic linker. 63346b754c76bd6a720dd1dd3be248cb93a4e25d3e5Chris Lattner // 634ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // Because of this, we have a couple of options: 63528275fdf02885587156da5cb20388b22d5b96557Bill Wendling // 636ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // 1) If we are in -static mode, we can always use an absolute reference 637ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // from the LSDA, because the static linker will resolve it. 63828275fdf02885587156da5cb20388b22d5b96557Bill Wendling // 639ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // 2) Otherwise, if the LSDA section is writable, we can output the direct 640ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // reference to the typeinfo and allow the dynamic linker to relocate 641ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // it. Since it is in a writable section, the dynamic linker won't 642ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // have a problem. 64328275fdf02885587156da5cb20388b22d5b96557Bill Wendling // 644ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // 3) Finally, if we're in PIC mode and the LDSA section isn't writable, 645ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // we need to use some form of indirection. For example, on Darwin, 646ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // we can output a statically-relocatable reference to a dyld stub. The 647ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // offset to the stub is constant, but the contents are in a section 648ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // that is updated by the dynamic linker. This is easy enough, but we 649ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // need to tell the personality function of the unwinder to indirect 650ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // through the dyld stub. 651ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // 65243e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling // FIXME: When (3) is actually implemented, we'll have to emit the stubs 653ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // somewhere. This predicate should be moved to a shared location that is 654ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // in target-independent code. 655ad88bc4076d088baad8a5ee9561e46ac08a1c88aChris Lattner // 65643e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling if (LSDASection->getKind().isWriteable() || 65743e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling Asm->TM.getRelocationModel() == Reloc::Static) 65843e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling TTypeFormat = dwarf::DW_EH_PE_absptr; 65943e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling else 66043e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling TTypeFormat = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 66143e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling dwarf::DW_EH_PE_sdata4; 662a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling 663a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling TypeFormatSize = SizeOfEncodedValue(TTypeFormat); 664fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling } 665fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling 666fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling // Begin the exception table. 667fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->OutStreamer.SwitchSection(LSDASection); 668fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->EmitAlignment(2, 0, 0, false); 66943e484fbcf6a40a70d9a5c7ea142f37416ef1e68Bill Wendling 670fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling O << "GCC_except_table" << SubprogramCount << ":\n"; 671a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling 672a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // The type infos need to be aligned. GCC does this by inserting padding just 673a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // before the type infos. However, this changes the size of the exception 674a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // table, so you need to take this into account when you output the exception 675a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // table size. However, the size is output using a variable length encoding. 676a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // So by increasing the size by inserting padding, you may increase the number 677a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // of bytes used for writing the size. If it increases, say by one byte, then 678a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // you now need to output one less byte of padding to get the type infos 679a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // aligned. However this decreases the size of the exception table. This 680a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // changes the value you have to output for the exception table size. Due to 681a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // the variable length encoding, the number of bytes used for writing the 682a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // length may decrease. If so, you then have to increase the amount of 683a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // padding. And so on. If you look carefully at the GCC code you will see that 684a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // it indeed does this in a loop, going on and on until the values stabilize. 685a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // We chose another solution: don't output padding inside the table like GCC 686a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling // does, instead output it before the table. 687a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling unsigned SizeTypes = TypeInfos.size() * TypeFormatSize; 688a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling unsigned TyOffset = sizeof(int8_t) + // Call site format 689a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling MCAsmInfo::getULEB128Size(SizeSites) + // Call-site table length 690a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling SizeSites + SizeActions + SizeTypes; 691a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling unsigned TotalSize = sizeof(int8_t) + // LPStart format 692a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling sizeof(int8_t) + // TType format 693a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling (HaveTTData ? 694a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling MCAsmInfo::getULEB128Size(TyOffset) : 0) + // TType base offset 695a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling TyOffset; 696a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling unsigned SizeAlign = (4 - TotalSize) & 3; 697a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling 698a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling for (unsigned i = 0; i != SizeAlign; ++i) { 699a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling Asm->EmitInt8(0); 700a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling Asm->EOL("Padding"); 701a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling } 702a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling 703fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling EmitLabel("exception", SubprogramCount); 704fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling 705fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling if (IsSJLJ) { 706fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling SmallString<16> LSDAName; 707fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling raw_svector_ostream(LSDAName) << MAI->getPrivateGlobalPrefix() << 708fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling "_LSDA_" << Asm->getFunctionNumber(); 709fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling O << LSDAName.str() << ":\n"; 710fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling } 711fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling 712fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling // Emit the header. 713fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->EmitInt8(dwarf::DW_EH_PE_omit); 714fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->EOL("@LPStart format", dwarf::DW_EH_PE_omit); 715fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling 716fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->EmitInt8(TTypeFormat); 717fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling Asm->EOL("@TType format", TTypeFormat); 718fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling 719fe220285b5ef1e4480ddd7f7c8bb182b88a33b16Bill Wendling if (HaveTTData) { 720a2f6449a57fcce73beacc30158aafe39b5349947Bill Wendling Asm->EmitULEB128Bytes(TyOffset); 721a583c55864e83e470333b7be878280b10e175a6eBill Wendling Asm->EOL("@TType base offset"); 7221b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } 723b0d9c3e7fdc952ae7cbe169b01ccaf1b80329403Bill Wendling 72428275fdf02885587156da5cb20388b22d5b96557Bill Wendling // SjLj Exception handling 725d1a5b37a62e829e56b6225e0934a01d9f8823387Bill Wendling if (IsSJLJ) { 726639217cb6a3948800c71c39503f8def4873a535eBill Wendling Asm->EmitInt8(dwarf::DW_EH_PE_udata4); 7270734d35044c304dd072f20e49840bcbea427db9cBill Wendling Asm->EOL("Call site format", dwarf::DW_EH_PE_udata4); 7281b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EmitULEB128Bytes(SizeSites); 729a583c55864e83e470333b7be878280b10e175a6eBill Wendling Asm->EOL("Call site table length"); 7301b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach 7311b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach // Emit the landing pad site information. 7328b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach unsigned idx = 0; 7338b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach for (SmallVectorImpl<CallSiteEntry>::const_iterator 7348b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach I = CallSites.begin(), E = CallSites.end(); I != E; ++I, ++idx) { 7358b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach const CallSiteEntry &S = *I; 736a583c55864e83e470333b7be878280b10e175a6eBill Wendling 737a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Offset of the landing pad, counted in 16-byte bundles relative to the 738a583c55864e83e470333b7be878280b10e175a6eBill Wendling // @LPStart address. 7398b818d7e98309125c6058c4ea72a7dc73b031db2Jim Grosbach Asm->EmitULEB128Bytes(idx); 7401b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Landing pad"); 741a583c55864e83e470333b7be878280b10e175a6eBill Wendling 742a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Offset of the first associated action record, relative to the start of 743a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the action table. This value is biased by 1 (1 indicates the start of 744a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the action table), and 0 indicates that there are no actions. 7451b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EmitULEB128Bytes(S.Action); 7461b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Action"); 7471b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } 7481b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } else { 7491b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach // DWARF Exception handling 75033adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner assert(MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf); 7511b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach 752a583c55864e83e470333b7be878280b10e175a6eBill Wendling // The call-site table is a list of all call sites that may throw an 753a583c55864e83e470333b7be878280b10e175a6eBill Wendling // exception (including C++ 'throw' statements) in the procedure 754a583c55864e83e470333b7be878280b10e175a6eBill Wendling // fragment. It immediately follows the LSDA header. Each entry indicates, 755a583c55864e83e470333b7be878280b10e175a6eBill Wendling // for a given call, the first corresponding action record and corresponding 756a583c55864e83e470333b7be878280b10e175a6eBill Wendling // landing pad. 757a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 758a583c55864e83e470333b7be878280b10e175a6eBill Wendling // The table begins with the number of bytes, stored as an LEB128 759a583c55864e83e470333b7be878280b10e175a6eBill Wendling // compressed, unsigned integer. The records immediately follow the record 760a583c55864e83e470333b7be878280b10e175a6eBill Wendling // count. They are sorted in increasing call-site address. Each record 761a583c55864e83e470333b7be878280b10e175a6eBill Wendling // indicates: 762a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 763a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * The position of the call-site. 764a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * The position of the landing pad. 765a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * The first action record for that call site. 766a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 767a583c55864e83e470333b7be878280b10e175a6eBill Wendling // A missing entry in the call-site table indicates that a call is not 76828275fdf02885587156da5cb20388b22d5b96557Bill Wendling // supposed to throw. 769a583c55864e83e470333b7be878280b10e175a6eBill Wendling 770a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Emit the landing pad call site table. 771639217cb6a3948800c71c39503f8def4873a535eBill Wendling Asm->EmitInt8(dwarf::DW_EH_PE_udata4); 7720734d35044c304dd072f20e49840bcbea427db9cBill Wendling Asm->EOL("Call site format", dwarf::DW_EH_PE_udata4); 7731b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EmitULEB128Bytes(SizeSites); 774a583c55864e83e470333b7be878280b10e175a6eBill Wendling Asm->EOL("Call site table size"); 775eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 7761b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach for (SmallVectorImpl<CallSiteEntry>::const_iterator 7775cff487665097d971067cbede1598e249f673182Bill Wendling I = CallSites.begin(), E = CallSites.end(); I != E; ++I) { 7781b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach const CallSiteEntry &S = *I; 7791b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach const char *BeginTag; 7801b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach unsigned BeginNumber; 781eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 7821b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach if (!S.BeginLabel) { 7831b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach BeginTag = "eh_func_begin"; 7841b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach BeginNumber = SubprogramCount; 7851b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } else { 7861b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach BeginTag = "label"; 7871b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach BeginNumber = S.BeginLabel; 7881b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } 789eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 790a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Offset of the call site relative to the previous call site, counted in 791a583c55864e83e470333b7be878280b10e175a6eBill Wendling // number of 16-byte bundles. The first call site is counted relative to 792a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the start of the procedure fragment. 7931b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach EmitSectionOffset(BeginTag, "eh_func_begin", BeginNumber, SubprogramCount, 7941b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach true, true); 7951b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Region start"); 796eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 7971b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach if (!S.EndLabel) 7981b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach EmitDifference("eh_func_end", SubprogramCount, BeginTag, BeginNumber, 7991b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach true); 8001b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach else 8011b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, true); 802eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 8031b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Region length"); 804eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 805a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Offset of the landing pad, counted in 16-byte bundles relative to the 806a583c55864e83e470333b7be878280b10e175a6eBill Wendling // @LPStart address. 8071b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach if (!S.PadLabel) 8081b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EmitInt32(0); 8091b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach else 8101b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach EmitSectionOffset("label", "eh_func_begin", S.PadLabel, SubprogramCount, 8111b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach true, true); 812eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 8131b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Landing pad"); 814eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 815a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Offset of the first associated action record, relative to the start of 816a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the action table. This value is biased by 1 (1 indicates the start of 817a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the action table), and 0 indicates that there are no actions. 8181b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EmitULEB128Bytes(S.Action); 8191b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach Asm->EOL("Action"); 8201b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach } 821eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 822eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 823a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Emit the Action Table. 8245cff487665097d971067cbede1598e249f673182Bill Wendling for (SmallVectorImpl<ActionEntry>::const_iterator 8255cff487665097d971067cbede1598e249f673182Bill Wendling I = Actions.begin(), E = Actions.end(); I != E; ++I) { 8265cff487665097d971067cbede1598e249f673182Bill Wendling const ActionEntry &Action = *I; 827a583c55864e83e470333b7be878280b10e175a6eBill Wendling 828a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Type Filter 829a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 830a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Used by the runtime to match the type of the thrown exception to the 831a583c55864e83e470333b7be878280b10e175a6eBill Wendling // type of the catch clauses or the types in the exception specification. 832a583c55864e83e470333b7be878280b10e175a6eBill Wendling 833eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitSLEB128Bytes(Action.ValueForTypeID); 834eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("TypeInfo index"); 835a583c55864e83e470333b7be878280b10e175a6eBill Wendling 836a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Action Record 837a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 838a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Self-relative signed displacement in bytes of the next action record, 839a583c55864e83e470333b7be878280b10e175a6eBill Wendling // or 0 if there is no next action record. 840a583c55864e83e470333b7be878280b10e175a6eBill Wendling 841eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitSLEB128Bytes(Action.NextAction); 842eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Next action"); 843eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 844eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 845a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Emit the Catch Clauses. The code for the catch clauses following the same 846a583c55864e83e470333b7be878280b10e175a6eBill Wendling // try is similar to a switch statement. The catch clause action record 847a583c55864e83e470333b7be878280b10e175a6eBill Wendling // informs the runtime about the type of a catch clause and about the 848a583c55864e83e470333b7be878280b10e175a6eBill Wendling // associated switch value. 849a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 850a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Action Record Fields: 851dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher // 852a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * Filter Value 853a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Positive value, starting at 1. Index in the types table of the 854a583c55864e83e470333b7be878280b10e175a6eBill Wendling // __typeinfo for the catch-clause type. 1 is the first word preceding 855a583c55864e83e470333b7be878280b10e175a6eBill Wendling // TTBase, 2 is the second word, and so on. Used by the runtime to check 856a583c55864e83e470333b7be878280b10e175a6eBill Wendling // if the thrown exception type matches the catch-clause type. Back-end 857a583c55864e83e470333b7be878280b10e175a6eBill Wendling // generated switch statements check against this value. 858a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 859a583c55864e83e470333b7be878280b10e175a6eBill Wendling // * Next 860a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Signed offset, in bytes from the start of this field, to the next 861a583c55864e83e470333b7be878280b10e175a6eBill Wendling // chained action record, or zero if none. 862a583c55864e83e470333b7be878280b10e175a6eBill Wendling // 863a583c55864e83e470333b7be878280b10e175a6eBill Wendling // The order of the action records determined by the next field is the order 864a583c55864e83e470333b7be878280b10e175a6eBill Wendling // of the catch clauses as they appear in the source code, and must be kept in 865a583c55864e83e470333b7be878280b10e175a6eBill Wendling // the same order. As a result, changing the order of the catch clause would 866a583c55864e83e470333b7be878280b10e175a6eBill Wendling // change the semantics of the program. 8675cff487665097d971067cbede1598e249f673182Bill Wendling for (std::vector<GlobalVariable *>::const_reverse_iterator 8685cff487665097d971067cbede1598e249f673182Bill Wendling I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) { 869a583c55864e83e470333b7be878280b10e175a6eBill Wendling const GlobalVariable *GV = *I; 870eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling PrintRelDirective(); 871eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 872eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (GV) { 873eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling std::string GLN; 874eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling O << Asm->getGlobalLinkName(GV, GLN); 875eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } else { 876049e98d641f90e90e8312d76cbf4c68908fb9d1dBill Wendling O << "0x0"; 877eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 878eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 879eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("TypeInfo"); 880eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 881eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 882a583c55864e83e470333b7be878280b10e175a6eBill Wendling // Emit the Type Table. 8835cff487665097d971067cbede1598e249f673182Bill Wendling for (std::vector<unsigned>::const_iterator 8845cff487665097d971067cbede1598e249f673182Bill Wendling I = FilterIds.begin(), E = FilterIds.end(); I < E; ++I) { 8855cff487665097d971067cbede1598e249f673182Bill Wendling unsigned TypeID = *I; 886eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitULEB128Bytes(TypeID); 887eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EOL("Filter TypeInfo index"); 888eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling } 889eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 890eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling Asm->EmitAlignment(2, 0, 0, false); 891eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 892eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 893eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// EndModule - Emit all exception information that should come after the 894eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// content. 895eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingvoid DwarfException::EndModule() { 89633adcfb4d217f5f23d9bde8ba02b8e48f9605fc5Chris Lattner if (MAI->getExceptionHandlingType() != ExceptionHandling::Dwarf) 8971b747ad8a0694b86e8d98a8b9a05ddfe74ec0cd3Jim Grosbach return; 898b4049fe8cbb38416522f7b214f028ef0b7693d21Bill Wendling 89952783c63a13d384582997684384553e6545852d3Bill Wendling if (!shouldEmitMovesModule && !shouldEmitTableModule) 90052783c63a13d384582997684384553e6545852d3Bill Wendling return; 90152783c63a13d384582997684384553e6545852d3Bill Wendling 902eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (TimePassesIsEnabled) 903eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->startTimer(); 904eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 90552783c63a13d384582997684384553e6545852d3Bill Wendling const std::vector<Function *> Personalities = MMI->getPersonalities(); 906b4049fe8cbb38416522f7b214f028ef0b7693d21Bill Wendling 90728275fdf02885587156da5cb20388b22d5b96557Bill Wendling for (unsigned I = 0, E = Personalities.size(); I < E; ++I) 90828275fdf02885587156da5cb20388b22d5b96557Bill Wendling EmitCIE(Personalities[I], I); 909eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 91052783c63a13d384582997684384553e6545852d3Bill Wendling for (std::vector<FunctionEHFrameInfo>::iterator 91152783c63a13d384582997684384553e6545852d3Bill Wendling I = EHFrames.begin(), E = EHFrames.end(); I != E; ++I) 91252783c63a13d384582997684384553e6545852d3Bill Wendling EmitFDE(*I); 913eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 914eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (TimePassesIsEnabled) 915eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->stopTimer(); 916eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 917eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 91828275fdf02885587156da5cb20388b22d5b96557Bill Wendling/// BeginFunction - Gather pre-function exception information. Assumes it's 91928275fdf02885587156da5cb20388b22d5b96557Bill Wendling/// being emitted immediately after the function entry point. 920eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingvoid DwarfException::BeginFunction(MachineFunction *MF) { 92173c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling if (!MMI || !MAI->doesSupportExceptionHandling()) return; 92273c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling 923eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (TimePassesIsEnabled) 924eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->startTimer(); 925eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 926eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling this->MF = MF; 927eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling shouldEmitTable = shouldEmitMoves = false; 928eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 92973c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling // Map all labels and get rid of any dead landing pads. 93073c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling MMI->TidyLandingPads(); 931eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 93273c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling // If any landing pads survive, we need an EH table. 93373c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling if (!MMI->getLandingPads().empty()) 93473c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling shouldEmitTable = true; 935eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 93673c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling // See if we need frame move info. 93773c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling if (!MF->getFunction()->doesNotThrow() || UnwindTablesMandatory) 93873c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling shouldEmitMoves = true; 939eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 94073c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling if (shouldEmitMoves || shouldEmitTable) 94173c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling // Assumes in correct section after the entry point. 94273c5a6172508e957d0b1a46170cb070dce6cac4fBill Wendling EmitLabel("eh_func_begin", ++SubprogramCount); 943eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 944eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling shouldEmitTableModule |= shouldEmitTable; 945eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling shouldEmitMovesModule |= shouldEmitMoves; 946eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 947eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling if (TimePassesIsEnabled) 948eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->stopTimer(); 949eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 950eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 951eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// EndFunction - Gather and emit post-function exception information. 952eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling/// 953eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendlingvoid DwarfException::EndFunction() { 9547b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling if (!shouldEmitMoves && !shouldEmitTable) return; 9557b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling 956dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher if (TimePassesIsEnabled) 957eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->startTimer(); 958eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 9597b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling EmitLabel("eh_func_end", SubprogramCount); 9607b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling EmitExceptionTable(); 9617b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling 9627b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling // Save EH frame information 9637b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling EHFrames.push_back(FunctionEHFrameInfo(getAsm()->getCurrentFunctionEHName(MF), 9647b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling SubprogramCount, 9657b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling MMI->getPersonalityIndex(), 9667b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling MF->getFrameInfo()->hasCalls(), 9677b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling !MMI->getLandingPads().empty(), 9687b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling MMI->getFrameMoves(), 9697b09a6c62215e5ed30443b0d2b2a5ae18b89b94fBill Wendling MF->getFunction())); 970eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling 97152783c63a13d384582997684384553e6545852d3Bill Wendling // Record if this personality index uses a landing pad. 97252783c63a13d384582997684384553e6545852d3Bill Wendling UsesLSDA[MMI->getPersonalityIndex()] |= !MMI->getLandingPads().empty(); 97352783c63a13d384582997684384553e6545852d3Bill Wendling 974dbfcdb976367ad5a9d3541fef90cd9f8dde7e2b4Eric Christopher if (TimePassesIsEnabled) 975eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling ExceptionTimer->stopTimer(); 976eb9072195ca7d777a71194dcaaaa369d82f24f53Bill Wendling} 977