1 //===-- AArch64MCAsmInfo.cpp - AArch64 asm properties ---------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains the declarations of the AArch64MCAsmInfo properties. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "AArch64MCAsmInfo.h" 15 #include "llvm/ADT/Triple.h" 16 #include "llvm/MC/MCExpr.h" 17 #include "llvm/MC/MCContext.h" 18 #include "llvm/MC/MCStreamer.h" 19 #include "llvm/Support/CommandLine.h" 20 using namespace llvm; 21 22 enum AsmWriterVariantTy { 23 Default = -1, 24 Generic = 0, 25 Apple = 1 26 }; 27 28 static cl::opt<AsmWriterVariantTy> AsmWriterVariant( 29 "aarch64-neon-syntax", cl::init(Default), 30 cl::desc("Choose style of NEON code to emit from AArch64 backend:"), 31 cl::values(clEnumValN(Generic, "generic", "Emit generic NEON assembly"), 32 clEnumValN(Apple, "apple", "Emit Apple-style NEON assembly"), 33 clEnumValEnd)); 34 35 AArch64MCAsmInfoDarwin::AArch64MCAsmInfoDarwin() { 36 // We prefer NEON instructions to be printed in the short form. 37 AssemblerDialect = AsmWriterVariant == Default ? 1 : AsmWriterVariant; 38 39 PrivateGlobalPrefix = "L"; 40 SeparatorString = "%%"; 41 CommentString = ";"; 42 PointerSize = CalleeSaveStackSlotSize = 8; 43 44 AlignmentIsInBytes = false; 45 UsesELFSectionDirectiveForBSS = true; 46 SupportsDebugInformation = true; 47 UseDataRegionDirectives = true; 48 49 ExceptionsType = ExceptionHandling::DwarfCFI; 50 } 51 52 const MCExpr *AArch64MCAsmInfoDarwin::getExprForPersonalitySymbol( 53 const MCSymbol *Sym, unsigned Encoding, MCStreamer &Streamer) const { 54 // On Darwin, we can reference dwarf symbols with foo@GOT-., which 55 // is an indirect pc-relative reference. The default implementation 56 // won't reference using the GOT, so we need this target-specific 57 // version. 58 MCContext &Context = Streamer.getContext(); 59 const MCExpr *Res = 60 MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_GOT, Context); 61 MCSymbol *PCSym = Context.CreateTempSymbol(); 62 Streamer.EmitLabel(PCSym); 63 const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context); 64 return MCBinaryExpr::CreateSub(Res, PC, Context); 65 } 66 67 AArch64MCAsmInfoELF::AArch64MCAsmInfoELF(StringRef TT) { 68 Triple T(TT); 69 if (T.getArch() == Triple::arm64_be || T.getArch() == Triple::aarch64_be) 70 IsLittleEndian = false; 71 72 // We prefer NEON instructions to be printed in the short form. 73 AssemblerDialect = AsmWriterVariant == Default ? 0 : AsmWriterVariant; 74 75 PointerSize = 8; 76 77 // ".comm align is in bytes but .align is pow-2." 78 AlignmentIsInBytes = false; 79 80 CommentString = "//"; 81 PrivateGlobalPrefix = ".L"; 82 Code32Directive = ".code\t32"; 83 84 Data16bitsDirective = "\t.hword\t"; 85 Data32bitsDirective = "\t.word\t"; 86 Data64bitsDirective = "\t.xword\t"; 87 88 UseDataRegionDirectives = false; 89 90 WeakRefDirective = "\t.weak\t"; 91 92 HasLEB128 = true; 93 SupportsDebugInformation = true; 94 95 // Exceptions handling 96 ExceptionsType = ExceptionHandling::DwarfCFI; 97 98 UseIntegratedAssembler = true; 99 100 HasIdentDirective = true; 101 } 102