1d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang//===-- PPCMachObjectWriter.cpp - PPC Mach-O Writer -----------------------===// 2d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// 3d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// The LLVM Compiler Infrastructure 4d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// 5d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// This file is distributed under the University of Illinois Open Source 6d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// License. See LICENSE.TXT for details. 7d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// 8d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang//===----------------------------------------------------------------------===// 9d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 10d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "MCTargetDesc/PPCMCTargetDesc.h" 11d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "MCTargetDesc/PPCFixupKinds.h" 12d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/ADT/Twine.h" 13d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCAsmLayout.h" 14d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCAssembler.h" 15d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCContext.h" 16d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCMachObjectWriter.h" 17d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCSectionMachO.h" 18d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/MC/MCValue.h" 19d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/Support/ErrorHandling.h" 20d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang#include "llvm/Support/Format.h" 215510728d28bb1ee04abc32da3d21b7df12948053Charles Davis#include "llvm/Support/MachO.h" 22d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 23d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangusing namespace llvm; 24d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 25d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangnamespace { 26d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangclass PPCMachObjectWriter : public MCMachObjectTargetWriter { 276948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar bool recordScatteredRelocation(MachObjectWriter *Writer, 28d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCAssembler &Asm, 29d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCAsmLayout &Layout, 30d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFragment *Fragment, 31d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixup &Fixup, MCValue Target, 32d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang unsigned Log2Size, uint64_t &FixedValue); 33d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 34d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang void RecordPPCRelocation(MachObjectWriter *Writer, const MCAssembler &Asm, 35d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCAsmLayout &Layout, 36d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFragment *Fragment, const MCFixup &Fixup, 37d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang MCValue Target, uint64_t &FixedValue); 38d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 39d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangpublic: 40d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang PPCMachObjectWriter(bool Is64Bit, uint32_t CPUType, uint32_t CPUSubtype) 416948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar : MCMachObjectTargetWriter(Is64Bit, CPUType, CPUSubtype) {} 42d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 436948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar void recordRelocation(MachObjectWriter *Writer, MCAssembler &Asm, 44d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCAsmLayout &Layout, const MCFragment *Fragment, 45d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixup &Fixup, MCValue Target, 46dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines uint64_t &FixedValue) override { 47d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (Writer->is64Bit()) { 48d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("Relocation emission for MachO/PPC64 unimplemented."); 49d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } else 50d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang RecordPPCRelocation(Writer, Asm, Layout, Fragment, Fixup, Target, 51d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue); 52d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 53d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang}; 54d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 55d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 56d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// computes the log2 of the size of the relocation, 57d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// used for relocation_info::r_length. 58d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangstatic unsigned getFixupKindLog2Size(unsigned Kind) { 59d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch (Kind) { 60d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 61d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("log2size(FixupKind): Unhandled fixup kind!"); 62d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_PCRel_1: 63d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_1: 64d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return 0; 65d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_PCRel_2: 66d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_2: 67d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return 1; 68d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_PCRel_4: 69d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_brcond14: 70d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_half16: 71d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_br24: 72d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_4: 73d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return 2; 74d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_PCRel_8: 75d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_8: 76d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return 3; 77d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 78d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return 0; 79d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 80d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 81d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// Translates generic PPC fixup kind to Mach-O/PPC relocation type enum. 82de2d8694e25a814696358e95141f4b1aa4d8847ePirama Arumuga Nainar/// Outline based on PPCELFObjectWriter::getRelocType(). 83d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangstatic unsigned getRelocType(const MCValue &Target, 84d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixupKind FixupKind, // from 85d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Fixup.getKind() 86d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const bool IsPCRel) { 87d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCSymbolRefExpr::VariantKind Modifier = 88d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang Target.isAbsolute() ? MCSymbolRefExpr::VK_None 89d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang : Target.getSymA()->getKind(); 90d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // determine the type of the relocation 915510728d28bb1ee04abc32da3d21b7df12948053Charles Davis unsigned Type = MachO::GENERIC_RELOC_VANILLA; 92d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (IsPCRel) { // relative to PC 93d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch ((unsigned)FixupKind) { 94d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 95d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("Unimplemented fixup kind (relative)"); 96d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_br24: 975510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_BR24; // R_PPC_REL24 98d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 99d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_brcond14: 1005510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_BR14; 101d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 102d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_half16: 103d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch (Modifier) { 104d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 105d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang llvm_unreachable("Unsupported modifier for half16 fixup"); 106d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_HA: 1075510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_HA16; 108d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 109d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_LO: 1105510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_LO16; 111d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 112d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_HI: 1135510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_HI16; 114d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 115d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 116d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 117d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 118d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } else { 119d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch ((unsigned)FixupKind) { 120d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 121d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("Unimplemented fixup kind (absolute)!"); 122d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case PPC::fixup_ppc_half16: 123d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch (Modifier) { 124d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 125d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang llvm_unreachable("Unsupported modifier for half16 fixup"); 126d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_HA: 1275510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_HA16_SECTDIFF; 128d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 129d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_LO: 1305510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_LO16_SECTDIFF; 131d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 132d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case MCSymbolRefExpr::VK_PPC_HI: 1335510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type = MachO::PPC_RELOC_HI16_SECTDIFF; 134d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 135d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 136d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 137d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_4: 138d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 139d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang case FK_Data_2: 140d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 141d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 142d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 143d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return Type; 144d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 145d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 1465510728d28bb1ee04abc32da3d21b7df12948053Charles Davisstatic void makeRelocationInfo(MachO::any_relocation_info &MRE, 147d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const uint32_t FixupOffset, const uint32_t Index, 148d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned IsPCRel, const unsigned Log2Size, 149d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned IsExtern, const unsigned Type) { 1505510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MRE.r_word0 = FixupOffset; 151d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // The bitfield offsets that work (as determined by trial-and-error) 152d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // are different than what is documented in the mach-o manuals. 1535510728d28bb1ee04abc32da3d21b7df12948053Charles Davis // This appears to be an endianness issue; reversing the order of the 1545510728d28bb1ee04abc32da3d21b7df12948053Charles Davis // documented bitfields in <llvm/Support/MachO.h> fixes this (but 1555510728d28bb1ee04abc32da3d21b7df12948053Charles Davis // breaks x86/ARM assembly). 1565510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MRE.r_word1 = ((Index << 8) | // was << 0 1575510728d28bb1ee04abc32da3d21b7df12948053Charles Davis (IsPCRel << 7) | // was << 24 1585510728d28bb1ee04abc32da3d21b7df12948053Charles Davis (Log2Size << 5) | // was << 25 1595510728d28bb1ee04abc32da3d21b7df12948053Charles Davis (IsExtern << 4) | // was << 27 1605510728d28bb1ee04abc32da3d21b7df12948053Charles Davis (Type << 0)); // was << 28 161d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 162d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 163d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangstatic void 1645510728d28bb1ee04abc32da3d21b7df12948053Charles DavismakeScatteredRelocationInfo(MachO::any_relocation_info &MRE, 1655510728d28bb1ee04abc32da3d21b7df12948053Charles Davis const uint32_t Addr, const unsigned Type, 1665510728d28bb1ee04abc32da3d21b7df12948053Charles Davis const unsigned Log2Size, const unsigned IsPCRel, 1675510728d28bb1ee04abc32da3d21b7df12948053Charles Davis const uint32_t Value2) { 168f69a29b23a116a3520f185054290c445abf9aa62Charles Davis // For notes on bitfield positions and endianness, see: 169f69a29b23a116a3520f185054290c445abf9aa62Charles Davis // https://developer.apple.com/library/mac/documentation/developertools/conceptual/MachORuntime/Reference/reference.html#//apple_ref/doc/uid/20001298-scattered_relocation_entry 1705510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MRE.r_word0 = ((Addr << 0) | (Type << 24) | (Log2Size << 28) | 1715510728d28bb1ee04abc32da3d21b7df12948053Charles Davis (IsPCRel << 30) | MachO::R_SCATTERED); 1725510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MRE.r_word1 = Value2; 173d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 174d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 175d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// Compute fixup offset (address). 176d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangstatic uint32_t getFixupOffset(const MCAsmLayout &Layout, 177d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFragment *Fragment, 178d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixup &Fixup) { 179d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang uint32_t FixupOffset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset(); 180d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // On Mach-O, ppc_fixup_half16 relocations must refer to the 181d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // start of the instruction, not the second halfword, as ELF does 182d76adee1b214fe1f5a26b8ffaec3e461beda6c88David Fang if (unsigned(Fixup.getKind()) == PPC::fixup_ppc_half16) 183d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixupOffset &= ~uint32_t(3); 184d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return FixupOffset; 185d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 186d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 187d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// \return false if falling back to using non-scattered relocation, 188d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang/// otherwise true for normal scattered relocation. 1896948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar/// based on X86MachObjectWriter::recordScatteredRelocation 1906948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar/// and ARMMachObjectWriter::recordScatteredRelocation 1916948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainarbool PPCMachObjectWriter::recordScatteredRelocation( 192d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang MachObjectWriter *Writer, const MCAssembler &Asm, const MCAsmLayout &Layout, 193d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target, 194d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang unsigned Log2Size, uint64_t &FixedValue) { 195d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // caller already computes these, can we just pass and reuse? 196d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const uint32_t FixupOffset = getFixupOffset(Layout, Fragment, Fixup); 197d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixupKind FK = Fixup.getKind(); 198d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, FK); 199d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned Type = getRelocType(Target, FK, IsPCRel); 200d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 201d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Is this a local or SECTDIFF relocation entry? 202d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // SECTDIFF relocation entries have symbol subtractions, 203d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // and require two entries, the first for the add-symbol value, 204d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // the second for the subtract-symbol value. 205d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 206d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // See <reloc.h>. 207d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCSymbol *A = &Target.getSymA()->getSymbol(); 208d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 2096948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (!A->getFragment()) 210d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("symbol '" + A->getName() + 211d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang "' can not be undefined in a subtraction expression"); 212d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 2136948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar uint32_t Value = Writer->getSymbolAddress(*A, Layout); 2146948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar uint64_t SecAddr = Writer->getSectionAddress(A->getFragment()->getParent()); 215d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue += SecAddr; 216d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang uint32_t Value2 = 0; 217d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 218d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (const MCSymbolRefExpr *B = Target.getSymB()) { 2196948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar const MCSymbol *SB = &B->getSymbol(); 220d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 2216948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (!SB->getFragment()) 222d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("symbol '" + B->getSymbol().getName() + 223d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang "' can not be undefined in a subtraction expression"); 224d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 2255510728d28bb1ee04abc32da3d21b7df12948053Charles Davis // FIXME: is Type correct? see include/llvm/Support/MachO.h 2266948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar Value2 = Writer->getSymbolAddress(B->getSymbol(), Layout); 2276948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar FixedValue -= Writer->getSectionAddress(SB->getFragment()->getParent()); 228d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 229d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // FIXME: does FixedValue get used?? 230d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 231d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Relocations are written out in reverse order, so the PAIR comes first. 2325510728d28bb1ee04abc32da3d21b7df12948053Charles Davis if (Type == MachO::PPC_RELOC_SECTDIFF || 2335510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type == MachO::PPC_RELOC_HI16_SECTDIFF || 2345510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type == MachO::PPC_RELOC_LO16_SECTDIFF || 2355510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type == MachO::PPC_RELOC_HA16_SECTDIFF || 2365510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type == MachO::PPC_RELOC_LO14_SECTDIFF || 2375510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Type == MachO::PPC_RELOC_LOCAL_SECTDIFF) { 238d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // X86 had this piece, but ARM does not 239d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // If the offset is too large to fit in a scattered relocation, 240d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // we're hosed. It's an unfortunate limitation of the MachO format. 241d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (FixupOffset > 0xffffff) { 242d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang char Buffer[32]; 243d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang format("0x%x", FixupOffset).print(Buffer, sizeof(Buffer)); 244f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar Asm.getContext().reportError(Fixup.getLoc(), 245d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang Twine("Section too large, can't encode " 246d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang "r_address (") + 247d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang Buffer + ") into 24 bits of scattered " 248d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang "relocation entry."); 249f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar return false; 250d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 251d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 252d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Is this supposed to follow MCTarget/PPCAsmBackend.cpp:adjustFixupValue()? 2536948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar // see PPCMCExpr::evaluateAsRelocatableImpl() 254d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang uint32_t other_half = 0; 255d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang switch (Type) { 2565510728d28bb1ee04abc32da3d21b7df12948053Charles Davis case MachO::PPC_RELOC_LO16_SECTDIFF: 257d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang other_half = (FixedValue >> 16) & 0xffff; 258d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // applyFixupOffset longer extracts the high part because it now assumes 259d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // this was already done. 260d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // It looks like this is not true for the FixedValue needed with Mach-O 261d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // relocs. 262d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // So we need to adjust FixedValue again here. 263d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue &= 0xffff; 264d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 2655510728d28bb1ee04abc32da3d21b7df12948053Charles Davis case MachO::PPC_RELOC_HA16_SECTDIFF: 266d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang other_half = FixedValue & 0xffff; 267d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue = 268d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang ((FixedValue >> 16) + ((FixedValue & 0x8000) ? 1 : 0)) & 0xffff; 269d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 2705510728d28bb1ee04abc32da3d21b7df12948053Charles Davis case MachO::PPC_RELOC_HI16_SECTDIFF: 271d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang other_half = FixedValue & 0xffff; 272d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue = (FixedValue >> 16) & 0xffff; 273d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 274d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang default: 275d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang llvm_unreachable("Invalid PPC scattered relocation type."); 276d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang break; 277d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 278d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 2795510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MachO::any_relocation_info MRE; 2805510728d28bb1ee04abc32da3d21b7df12948053Charles Davis makeScatteredRelocationInfo(MRE, other_half, MachO::GENERIC_RELOC_PAIR, 2815510728d28bb1ee04abc32da3d21b7df12948053Charles Davis Log2Size, IsPCRel, Value2); 282ebe69fe11e48d322045d5949c83283927a0d790bStephen Hines Writer->addRelocation(nullptr, Fragment->getParent(), MRE); 283d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } else { 284d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // If the offset is more than 24-bits, it won't fit in a scattered 285d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // relocation offset field, so we fall back to using a non-scattered 286d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // relocation. This is a bit risky, as if the offset reaches out of 287d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // the block and the linker is doing scattered loading on this 288d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // symbol, things can go badly. 289d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // 290d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Required for 'as' compatibility. 291d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (FixupOffset > 0xffffff) 292d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return false; 293d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 2945510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MachO::any_relocation_info MRE; 295d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang makeScatteredRelocationInfo(MRE, FixupOffset, Type, Log2Size, IsPCRel, Value); 296ebe69fe11e48d322045d5949c83283927a0d790bStephen Hines Writer->addRelocation(nullptr, Fragment->getParent(), MRE); 297d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return true; 298d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 299d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 300d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang// see PPCELFObjectWriter for a general outline of cases 301d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fangvoid PPCMachObjectWriter::RecordPPCRelocation( 302d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang MachObjectWriter *Writer, const MCAssembler &Asm, const MCAsmLayout &Layout, 303d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target, 304d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang uint64_t &FixedValue) { 305d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const MCFixupKind FK = Fixup.getKind(); // unsigned 306d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned Log2Size = getFixupKindLog2Size(FK); 307d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const bool IsPCRel = Writer->isFixupKindPCRel(Asm, FK); 308d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const unsigned RelocType = getRelocType(Target, FK, IsPCRel); 309d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 310d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // If this is a difference or a defined symbol plus an offset, then we need a 311d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // scattered relocation entry. Differences always require scattered 312d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // relocations. 313d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (Target.getSymB() && 314d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Q: are branch targets ever scattered? 3155510728d28bb1ee04abc32da3d21b7df12948053Charles Davis RelocType != MachO::PPC_RELOC_BR24 && 3165510728d28bb1ee04abc32da3d21b7df12948053Charles Davis RelocType != MachO::PPC_RELOC_BR14) { 3176948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar recordScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup, Target, 318d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang Log2Size, FixedValue); 319d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return; 320d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 321d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 322d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // this doesn't seem right for RIT_PPC_BR24 323d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Get the symbol data, if any. 3246948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar const MCSymbol *A = nullptr; 325d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (Target.getSymA()) 3266948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar A = &Target.getSymA()->getSymbol(); 327d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 328d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // See <reloc.h>. 329d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang const uint32_t FixupOffset = getFixupOffset(Layout, Fragment, Fixup); 330d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang unsigned Index = 0; 331d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang unsigned Type = RelocType; 332d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 3336948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar const MCSymbol *RelSymbol = nullptr; 334d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (Target.isAbsolute()) { // constant 335d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // SymbolNum of 0 indicates the absolute section. 336d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // 337d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // FIXME: Currently, these are never generated (see code below). I cannot 338d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // find a case where they are actually emitted. 339d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang report_fatal_error("FIXME: relocations to absolute targets " 340d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang "not yet implemented"); 341d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // the above line stolen from ARM, not sure 342d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } else { 343d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Resolve constant variables. 3446948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (A->isVariable()) { 345d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang int64_t Res; 3466948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (A->getVariableValue()->evaluateAsAbsolute( 347d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang Res, Layout, Writer->getSectionAddressMap())) { 348d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue = Res; 349d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return; 350d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 351d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 352d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 353d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // Check whether we need an external or internal relocation. 3546948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (Writer->doesSymbolRequireExternRelocation(*A)) { 3556948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar RelSymbol = A; 356d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // For external relocations, make sure to offset the fixup value to 357d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // compensate for the addend of the symbol address, if it was 358d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // undefined. This occurs with weak definitions, for example. 3596948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar if (!A->isUndefined()) 3606948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar FixedValue -= Layout.getSymbolOffset(*A); 361d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } else { 362d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang // The index is the section ordinal (1-based). 3636948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar const MCSection &Sec = A->getSection(); 3646948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar Index = Sec.getOrdinal() + 1; 3656948897e478cbd66626159776a8017b3c18579b9Pirama Arumuga Nainar FixedValue += Writer->getSectionAddress(&Sec); 366d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 367d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang if (IsPCRel) 368d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang FixedValue -= Writer->getSectionAddress(Fragment->getParent()); 369d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang } 370d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 371f69a29b23a116a3520f185054290c445abf9aa62Charles Davis // struct relocation_info (8 bytes) 3725510728d28bb1ee04abc32da3d21b7df12948053Charles Davis MachO::any_relocation_info MRE; 373ebe69fe11e48d322045d5949c83283927a0d790bStephen Hines makeRelocationInfo(MRE, FixupOffset, Index, IsPCRel, Log2Size, false, Type); 374ebe69fe11e48d322045d5949c83283927a0d790bStephen Hines Writer->addRelocation(RelSymbol, Fragment->getParent(), MRE); 375d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 376d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang 3770c7f116bb6950ef819323d855415b2f2b0aad987Pirama Arumuga NainarMCObjectWriter *llvm::createPPCMachObjectWriter(raw_pwrite_stream &OS, 3780c7f116bb6950ef819323d855415b2f2b0aad987Pirama Arumuga Nainar bool Is64Bit, uint32_t CPUType, 379d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang uint32_t CPUSubtype) { 380d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang return createMachObjectWriter( 381d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang new PPCMachObjectWriter(Is64Bit, CPUType, CPUSubtype), OS, 382d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang /*IsLittleEndian=*/false); 383d4f9d05fde4b2cfd202a5852ec1ec3e960ef53edDavid Fang} 384