1 //===-- AArch64MCAsmInfo.cpp - AArch64 asm properties ---------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file contains the declarations of the AArch64MCAsmInfo properties. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "AArch64MCAsmInfo.h" 14 #include "llvm/ADT/Triple.h" 15 #include "llvm/MC/MCContext.h" 16 #include "llvm/MC/MCExpr.h" 17 #include "llvm/MC/MCStreamer.h" 18 #include "llvm/Support/CommandLine.h" 19 using namespace llvm; 20 21 enum AsmWriterVariantTy { 22 Default = -1, 23 Generic = 0, 24 Apple = 1 25 }; 26 27 static cl::opt<AsmWriterVariantTy> AsmWriterVariant( 28 "aarch64-neon-syntax", cl::init(Default), 29 cl::desc("Choose style of NEON code to emit from AArch64 backend:"), 30 cl::values(clEnumValN(Generic, "generic", "Emit generic NEON assembly"), 31 clEnumValN(Apple, "apple", "Emit Apple-style NEON assembly"))); 32 33 AArch64MCAsmInfoDarwin::AArch64MCAsmInfoDarwin(bool IsILP32) { 34 // We prefer NEON instructions to be printed in the short, Apple-specific 35 // form when targeting Darwin. 36 AssemblerDialect = AsmWriterVariant == Default ? Apple : AsmWriterVariant; 37 38 PrivateGlobalPrefix = "L"; 39 PrivateLabelPrefix = "L"; 40 SeparatorString = "%%"; 41 CommentString = ";"; 42 CalleeSaveStackSlotSize = 8; 43 CodePointerSize = IsILP32 ? 4 : 8; 44 45 AlignmentIsInBytes = false; 46 UsesELFSectionDirectiveForBSS = true; 47 SupportsDebugInformation = true; 48 UseDataRegionDirectives = true; 49 50 ExceptionsType = ExceptionHandling::DwarfCFI; 51 } 52 53 const MCExpr *AArch64MCAsmInfoDarwin::getExprForPersonalitySymbol( 54 const MCSymbol *Sym, unsigned Encoding, MCStreamer &Streamer) const { 55 // On Darwin, we can reference dwarf symbols with foo@GOT-., which 56 // is an indirect pc-relative reference. The default implementation 57 // won't reference using the GOT, so we need this target-specific 58 // version. 59 MCContext &Context = Streamer.getContext(); 60 const MCExpr *Res = 61 MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOT, Context); 62 MCSymbol *PCSym = Context.createTempSymbol(); 63 Streamer.emitLabel(PCSym); 64 const MCExpr *PC = MCSymbolRefExpr::create(PCSym, Context); 65 return MCBinaryExpr::createSub(Res, PC, Context); 66 } 67 68 AArch64MCAsmInfoELF::AArch64MCAsmInfoELF(const Triple &T) { 69 if (T.getArch() == Triple::aarch64_be) 70 IsLittleEndian = false; 71 72 // We prefer NEON instructions to be printed in the generic form when 73 // targeting ELF. 74 AssemblerDialect = AsmWriterVariant == Default ? Generic : AsmWriterVariant; 75 76 CodePointerSize = T.getEnvironment() == Triple::GNUILP32 ? 4 : 8; 77 78 // ".comm align is in bytes but .align is pow-2." 79 AlignmentIsInBytes = false; 80 81 CommentString = "//"; 82 PrivateGlobalPrefix = ".L"; 83 PrivateLabelPrefix = ".L"; 84 Code32Directive = ".code\t32"; 85 86 Data16bitsDirective = "\t.hword\t"; 87 Data32bitsDirective = "\t.word\t"; 88 Data64bitsDirective = "\t.xword\t"; 89 90 UseDataRegionDirectives = false; 91 92 WeakRefDirective = "\t.weak\t"; 93 94 SupportsDebugInformation = true; 95 96 // Exceptions handling 97 ExceptionsType = ExceptionHandling::DwarfCFI; 98 99 HasIdentDirective = true; 100 } 101 102 AArch64MCAsmInfoMicrosoftCOFF::AArch64MCAsmInfoMicrosoftCOFF() { 103 PrivateGlobalPrefix = ".L"; 104 PrivateLabelPrefix = ".L"; 105 106 Data16bitsDirective = "\t.hword\t"; 107 Data32bitsDirective = "\t.word\t"; 108 Data64bitsDirective = "\t.xword\t"; 109 110 AlignmentIsInBytes = false; 111 SupportsDebugInformation = true; 112 CodePointerSize = 8; 113 114 CommentString = "//"; 115 ExceptionsType = ExceptionHandling::WinEH; 116 WinEHEncodingType = WinEH::EncodingType::Itanium; 117 } 118 119 AArch64MCAsmInfoGNUCOFF::AArch64MCAsmInfoGNUCOFF() { 120 PrivateGlobalPrefix = ".L"; 121 PrivateLabelPrefix = ".L"; 122 123 Data16bitsDirective = "\t.hword\t"; 124 Data32bitsDirective = "\t.word\t"; 125 Data64bitsDirective = "\t.xword\t"; 126 127 AlignmentIsInBytes = false; 128 SupportsDebugInformation = true; 129 CodePointerSize = 8; 130 131 CommentString = "//"; 132 ExceptionsType = ExceptionHandling::WinEH; 133 WinEHEncodingType = WinEH::EncodingType::Itanium; 134 } 135