//===-- X86MCAsmInfo.cpp - X86 asm properties -----------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file contains the declarations of the X86MCAsmInfo properties. // //===----------------------------------------------------------------------===// #include "X86MCAsmInfo.h" #include "llvm/ADT/Triple.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCSectionELF.h" #include "llvm/MC/MCStreamer.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/ELF.h" using namespace llvm; enum AsmWriterFlavorTy { // Note: This numbering has to match the GCC assembler dialects for inline // asm alternatives to work right. ATT = 0, Intel = 1 }; static cl::opt<AsmWriterFlavorTy> AsmWriterFlavor("x86-asm-syntax", cl::init(ATT), cl::desc("Choose style of code to emit from X86 backend:"), cl::values(clEnumValN(ATT, "att", "Emit AT&T-style assembly"), clEnumValN(Intel, "intel", "Emit Intel-style assembly"), clEnumValEnd)); static cl::opt<bool> MarkedJTDataRegions("mark-data-regions", cl::init(true), cl::desc("Mark code section jump table data regions."), cl::Hidden); void X86MCAsmInfoDarwin::anchor() { } X86MCAsmInfoDarwin::X86MCAsmInfoDarwin(const Triple &T) { bool is64Bit = T.getArch() == Triple::x86_64; if (is64Bit) PointerSize = CalleeSaveStackSlotSize = 8; AssemblerDialect = AsmWriterFlavor; TextAlignFillValue = 0x90; if (!is64Bit) Data64bitsDirective = nullptr; // we can't emit a 64-bit unit // Use ## as a comment string so that .s files generated by llvm can go // through the GCC preprocessor without causing an error. This is needed // because "clang foo.s" runs the C preprocessor, which is usually reserved // for .S files on other systems. Perhaps this is because the file system // wasn't always case preserving or something. CommentString = "##"; SupportsDebugInformation = true; UseDataRegionDirectives = MarkedJTDataRegions; // Exceptions handling ExceptionsType = ExceptionHandling::DwarfCFI; // old assembler lacks some directives // FIXME: this should really be a check on the assembler characteristics // rather than OS version if (T.isMacOSX() && T.isMacOSXVersionLT(10, 6)) HasWeakDefCanBeHiddenDirective = false; // Assume ld64 is new enough that the abs-ified FDE relocs may be used // (actually, must, since otherwise the non-extern relocations we produce // overwhelm ld64's tiny little mind and it fails). DwarfFDESymbolsUseAbsDiff = true; UseIntegratedAssembler = true; } X86_64MCAsmInfoDarwin::X86_64MCAsmInfoDarwin(const Triple &Triple) : X86MCAsmInfoDarwin(Triple) { } void X86ELFMCAsmInfo::anchor() { } X86ELFMCAsmInfo::X86ELFMCAsmInfo(const Triple &T) { bool is64Bit = T.getArch() == Triple::x86_64; bool isX32 = T.getEnvironment() == Triple::GNUX32; // For ELF, x86-64 pointer size depends on the ABI. // For x86-64 without the x32 ABI, pointer size is 8. For x86 and for x86-64 // with the x32 ABI, pointer size remains the default 4. PointerSize = (is64Bit && !isX32) ? 8 : 4; // OTOH, stack slot size is always 8 for x86-64, even with the x32 ABI. CalleeSaveStackSlotSize = is64Bit ? 8 : 4; AssemblerDialect = AsmWriterFlavor; TextAlignFillValue = 0x90; // Debug Information SupportsDebugInformation = true; // Exceptions handling ExceptionsType = ExceptionHandling::DwarfCFI; // Always enable the integrated assembler by default. // Clang also enabled it when the OS is Solaris but that is redundant here. UseIntegratedAssembler = true; } const MCExpr * X86_64MCAsmInfoDarwin::getExprForPersonalitySymbol(const MCSymbol *Sym, unsigned Encoding, MCStreamer &Streamer) const { MCContext &Context = Streamer.getContext(); const MCExpr *Res = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, Context); const MCExpr *Four = MCConstantExpr::create(4, Context); return MCBinaryExpr::createAdd(Res, Four, Context); } void X86MCAsmInfoMicrosoft::anchor() { } X86MCAsmInfoMicrosoft::X86MCAsmInfoMicrosoft(const Triple &Triple) { if (Triple.getArch() == Triple::x86_64) { PrivateGlobalPrefix = ".L"; PrivateLabelPrefix = ".L"; PointerSize = 8; WinEHEncodingType = WinEH::EncodingType::Itanium; } else { // 32-bit X86 doesn't use CFI, so this isn't a real encoding type. It's just // a place holder that the Windows EHStreamer looks for to suppress CFI // output. In particular, usesWindowsCFI() returns false. WinEHEncodingType = WinEH::EncodingType::X86; } ExceptionsType = ExceptionHandling::WinEH; AssemblerDialect = AsmWriterFlavor; TextAlignFillValue = 0x90; AllowAtInName = true; UseIntegratedAssembler = true; } void X86MCAsmInfoGNUCOFF::anchor() { } X86MCAsmInfoGNUCOFF::X86MCAsmInfoGNUCOFF(const Triple &Triple) { assert(Triple.isOSWindows() && "Windows is the only supported COFF target"); if (Triple.getArch() == Triple::x86_64) { PrivateGlobalPrefix = ".L"; PrivateLabelPrefix = ".L"; PointerSize = 8; WinEHEncodingType = WinEH::EncodingType::Itanium; ExceptionsType = ExceptionHandling::WinEH; } else { ExceptionsType = ExceptionHandling::DwarfCFI; } AssemblerDialect = AsmWriterFlavor; TextAlignFillValue = 0x90; UseIntegratedAssembler = true; }