/* * Copyright (c) 2010 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ #ifndef _MACHO_ARM64_RELOC_H_ #define _MACHO_ARM64_RELOC_H_ /* * Relocations for arm64 are a bit different than for other architectures in * Mach-O: Scattered relocations are not used. Almost all relocations produced * by the compiler are external relocations. An external relocation has the * r_extern bit set to 1 and the r_symbolnum field contains the symbol table * index of the target label. * * When the assembler is generating relocations, if the target label is a local * label (begins with 'L'), then the previous non-local label in the same * section is used as the target of the external relocation. An addend is used * with the distance from that non-local label to the target label. Only when * there is no previous non-local label in the section is an internal * relocation used. * * The addend (i.e. the 4 in _foo+4) is encoded either in the instruction or * in the r_symbolnum of ARM64_RELOC_ADDEND. * For ARM64_RELOC_UNSIGNED and ARM64_RELOC_AUTHENTICATED_POINTER, the addend * is stored in the instruction. ARM64_RELOC_PAGE21, ARM64_RELOC_PAGEOFF12 and * ARM64_RELOC_BRANCH26 must be preceded by an ARM64_RELOC_ADDEND if they need * an addend. No other relocations support addends. * * The relocation types are: * * ARM64_RELOC_UNSIGNED // For pointer sized fixups * ARM64_RELOC_SUBTRACTOR // must be followed by a ARM64_RELOC_UNSIGNED * ARM64_RELOC_BRANCH26 // a BL instruction with pc-relative +-128MB displacement * ARM64_RELOC_PAGE21 // pc-rel distance to page of target * ARM64_RELOC_PAGEOFF12 // offset within page, scaled by r_length * ARM64_RELOC_GOT_LOAD_PAGE21 // load with a pc-rel distance to page of a GOT entry * ARM64_RELOC_GOT_LOAD_PAGEOFF12 // load with an offset within page, scaled by r_length, of GOT entry * ARM64_RELOC_POINTER_TO_GOT // 32-bit pc-rel (or 64-bit absolute) offset to a GOT entry * ARM64_RELOC_TLVP_LOAD_PAGE21 // tlv load with a pc-rel distance to page of a GOT entry * ARM64_RELOC_TLVP_LOAD_PAGEOFF12 // tlv load with an offset within page, scaled by r_length, of GOT entry * ARM64_RELOC_ADDEND // must be followed by ARM64_RELOC_BRANCH26/ARM64_RELOC_PAGE21/ARM64_RELOC_PAGEOFF12 * ARM64_RELOC_AUTHENTICATED_POINTER // 64-bit pointer with authentication * * The following are sample assembly instructions, followed by the relocation * and section content they generate in an object file: * * (arm64_32 only) * .long _foo * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 * * (arm64_32 only) * .long _foo + 4 * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 04 00 00 00 * * .quad _foo * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 00 00 00 00 * * .quad _foo + 16 * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 10 00 00 00 00 00 00 00 * * .quad L1 * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_prev * 10 00 00 00 00 00 00 00 * // assumes _prev is the first non-local label 0x10 bytes before L1 * 10 00 00 00 00 00 00 00 * * (arm64_32 only) * .long _foo - _bar * r_type=ARM64_RELOC_SUBTRACTOR, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_bar * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 * * (arm64_32 only) * .long _foo - _bar + 4 * r_type=ARM64_RELOC_SUBTRACTOR, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_bar * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 04 00 00 00 * * .quad _foo - _bar * r_type=ARM64_RELOC_SUBTRACTOR, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_bar * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 00 00 00 00 * * .quad _foo - _bar + 4 * r_type=ARM64_RELOC_SUBTRACTOR, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_bar * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 04 00 00 00 00 00 00 00 * * .long _foo - . * r_type=ARM64_RELOC_SUBTRACTOR, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_prev * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * f8 ff ff ff * // assumes _prev is the first non-local label 0x8 bytes before this * // .quad * * .long _foo - L1 * r_type=ARM64_RELOC_SUBTRACTOR, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_prev * r_type=ARM64_RELOC_UNSIGNED, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * f8 ff ff ff * // assumes _prev is the first non-local label 0x8 bytes before L1 * * .quad _foo - . * r_type=ARM64_RELOC_SUBTRACTOR, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_prev * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * f8 ff ff ff ff ff ff ff * // assumes _prev is the first non-local label 0x8 bytes before this * // .quad * * .quad _foo - L1 * r_type=ARM64_RELOC_SUBTRACTOR, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_prev * r_type=ARM64_RELOC_UNSIGNED, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * f8 ff ff ff ff ff ff ff * // assumes _prev is the first non-local label 0x8 bytes before L1 * * .long L1 - _prev * // No relocations. This is an assembly time constant. * 12 00 00 00 00 00 00 00 * // assumes _prev is the first non-local label 0x12 bytes before L1 * * .quad L1 - _prev * // No relocations. This is an assembly time constant. * 12 00 00 00 00 00 00 00 * // assumes _prev is the first non-local label 0x12 bytes before L1 * * bl _foo * r_type=ARM64_RELOC_BRANCH26, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x14000000 * * bl _foo + 4 * r_type=ARM64_RELOC_ADDEND, r_length=2, r_extern=0, r_pcrel=0, r_symbolnum=0x000004 * r_type=ARM64_RELOC_BRANCH26, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x14000000 * * adrp x0, _foo@PAGE * r_type=ARM64_RELOC_PAGE21, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x90000000 * * ldr x0, [x0, _foo@PAGEOFF] * r_type=ARM64_RELOC_PAGEOFF12, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 0xf9400000 * * adrp x0, _foo@PAGE + 0x24 * r_type=ARM64_RELOC_ADDEND, r_length=2, r_extern=0, r_pcrel=0, r_symbolnum=0x000024 * r_type=ARM64_RELOC_PAGE21, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x90000000 * * ldr x0, [x0, _foo@PAGEOFF + 0x24] * r_type=ARM64_RELOC_ADDEND, r_length=2, r_extern=0, r_pcrel=0, r_symbolnum=0x000024 * r_type=ARM64_RELOC_PAGEOFF12, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 0xf9400000 * * adrp x0, _foo@GOTPAGE * r_type=ARM64_RELOC_GOT_LOAD_PAGE21, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x90000000 * * ldr x0, [x0, _foo@GOTPAGEOFF] * r_type=ARM64_RELOC_GOT_LOAD_PAGEOFF12, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 0xf9400000 * * adrp x0, _foo@TLVPPAGE * r_type=ARM64_RELOC_TLVP_LOAD_PAGE21, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 0x90000000 * * ldr x0, [x0, _foo@TLVPPAGEOFF] * r_type=ARM64_RELOC_TLVP_LOAD_PAGEOFF12, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 0xf9400000 * * .long _foo@GOT - . * r_type=ARM64_RELOC_POINTER_TO_GOT, r_length=2, r_extern=1, r_pcrel=1, r_symbolnum=_foo * 00 00 00 00 * * (arm64_32 only) * .long _foo@GOT * r_type=ARM64_RELOC_POINTER_TO_GOT, r_length=2, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 * * .quad _foo@GOT * r_type=ARM64_RELOC_POINTER_TO_GOT, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 00 00 00 00 * * (arm64e only) * .quad _foo@AUTH(da,5,addr) * r_type=ARM64_RELOC_AUTHENTICATED_POINTER, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 00 00 00 00 05 00 05 80 * * (arm64e only) * .quad (_foo + 0x10)@AUTH(da,5,addr) * r_type=ARM64_RELOC_AUTHENTICATED_POINTER, r_length=3, r_extern=1, r_pcrel=0, r_symbolnum=_foo * 10 00 00 00 05 00 05 80 * * */ enum reloc_type_arm64 { ARM64_RELOC_UNSIGNED, // for pointers ARM64_RELOC_SUBTRACTOR, // must be followed by a ARM64_RELOC_UNSIGNED ARM64_RELOC_BRANCH26, // a B/BL instruction with 26-bit displacement ARM64_RELOC_PAGE21, // pc-rel distance to page of target ARM64_RELOC_PAGEOFF12, // offset within page, scaled by r_length ARM64_RELOC_GOT_LOAD_PAGE21, // pc-rel distance to page of GOT slot ARM64_RELOC_GOT_LOAD_PAGEOFF12, // offset within page of GOT slot, // scaled by r_length ARM64_RELOC_POINTER_TO_GOT, // for pointers to GOT slots ARM64_RELOC_TLVP_LOAD_PAGE21, // pc-rel distance to page of TLVP slot ARM64_RELOC_TLVP_LOAD_PAGEOFF12, // offset within page of TLVP slot, // scaled by r_length ARM64_RELOC_ADDEND, // must be followed by PAGE21 or PAGEOFF12 // An arm64e authenticated pointer. // // Represents a pointer to a symbol (like ARM64_RELOC_UNSIGNED). // Additionally, the resulting pointer is signed. The signature is // specified in the target location: the addend is restricted to the lower // 32 bits (instead of the full 64 bits for ARM64_RELOC_UNSIGNED): // // |63|62|61-51|50-49| 48 |47 - 32|31 - 0| // | 1| 0| 0 | key | addr | discriminator | addend | // // The key is one of: // IA: 00 IB: 01 // DA: 10 DB: 11 // // The discriminator field is used as extra signature diversification. // // The addr field indicates whether the target address should be blended // into the discriminator. // ARM64_RELOC_AUTHENTICATED_POINTER, }; #endif /* #ifndef _MACHO_ARM64_RELOC_H_ */