1// Inferno utils/5l/asm.c 2// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/5l/asm.c 3// 4// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. 5// Portions Copyright © 1995-1997 C H Forsyth ([email protected]) 6// Portions Copyright © 1997-1999 Vita Nuova Limited 7// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com) 8// Portions Copyright © 2004,2006 Bruce Ellis 9// Portions Copyright © 2005-2007 C H Forsyth ([email protected]) 10// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others 11// Portions Copyright © 2016 The Go Authors. All rights reserved. 12// 13// Permission is hereby granted, free of charge, to any person obtaining a copy 14// of this software and associated documentation files (the "Software"), to deal 15// in the Software without restriction, including without limitation the rights 16// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 17// copies of the Software, and to permit persons to whom the Software is 18// furnished to do so, subject to the following conditions: 19// 20// The above copyright notice and this permission notice shall be included in 21// all copies or substantial portions of the Software. 22// 23// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 24// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 25// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 26// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 27// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 28// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 29// THE SOFTWARE. 30 31package mips 32 33import ( 34 "cmd/internal/objabi" 35 "cmd/internal/sys" 36 "cmd/link/internal/ld" 37 "cmd/link/internal/loader" 38 "cmd/link/internal/sym" 39 "debug/elf" 40) 41 42func gentext(ctxt *ld.Link, ldr *loader.Loader) { 43 return 44} 45 46func elfreloc1(ctxt *ld.Link, out *ld.OutBuf, ldr *loader.Loader, s loader.Sym, r loader.ExtReloc, ri int, sectoff int64) bool { 47 out.Write32(uint32(sectoff)) 48 49 elfsym := ld.ElfSymForReloc(ctxt, r.Xsym) 50 switch r.Type { 51 default: 52 return false 53 case objabi.R_ADDR, objabi.R_DWARFSECREF: 54 if r.Size != 4 { 55 return false 56 } 57 out.Write32(uint32(elf.R_MIPS_32) | uint32(elfsym)<<8) 58 case objabi.R_ADDRMIPS: 59 out.Write32(uint32(elf.R_MIPS_LO16) | uint32(elfsym)<<8) 60 case objabi.R_ADDRMIPSU: 61 out.Write32(uint32(elf.R_MIPS_HI16) | uint32(elfsym)<<8) 62 case objabi.R_ADDRMIPSTLS: 63 out.Write32(uint32(elf.R_MIPS_TLS_TPREL_LO16) | uint32(elfsym)<<8) 64 case objabi.R_CALLMIPS, objabi.R_JMPMIPS: 65 out.Write32(uint32(elf.R_MIPS_26) | uint32(elfsym)<<8) 66 } 67 68 return true 69} 70 71func elfsetupplt(ctxt *ld.Link, ldr *loader.Loader, plt, gotplt *loader.SymbolBuilder, dynamic loader.Sym) { 72 return 73} 74 75func machoreloc1(*sys.Arch, *ld.OutBuf, *loader.Loader, loader.Sym, loader.ExtReloc, int64) bool { 76 return false 77} 78 79func applyrel(arch *sys.Arch, ldr *loader.Loader, rt objabi.RelocType, off int32, s loader.Sym, val int64, t int64) int64 { 80 o := uint32(val) 81 switch rt { 82 case objabi.R_ADDRMIPS, objabi.R_ADDRMIPSTLS: 83 return int64(o&0xffff0000 | uint32(t)&0xffff) 84 case objabi.R_ADDRMIPSU: 85 return int64(o&0xffff0000 | uint32((t+(1<<15))>>16)&0xffff) 86 case objabi.R_CALLMIPS, objabi.R_JMPMIPS: 87 return int64(o&0xfc000000 | uint32(t>>2)&^0xfc000000) 88 default: 89 return val 90 } 91} 92 93func archreloc(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, r loader.Reloc, s loader.Sym, val int64) (o int64, nExtReloc int, ok bool) { 94 rs := r.Sym() 95 if target.IsExternal() { 96 switch r.Type() { 97 default: 98 return val, 0, false 99 100 case objabi.R_ADDRMIPS, objabi.R_ADDRMIPSU: 101 // set up addend for eventual relocation via outer symbol. 102 _, off := ld.FoldSubSymbolOffset(ldr, rs) 103 xadd := r.Add() + off 104 return applyrel(target.Arch, ldr, r.Type(), r.Off(), s, val, xadd), 1, true 105 106 case objabi.R_ADDRMIPSTLS, objabi.R_CALLMIPS, objabi.R_JMPMIPS: 107 return applyrel(target.Arch, ldr, r.Type(), r.Off(), s, val, r.Add()), 1, true 108 } 109 } 110 111 const isOk = true 112 const noExtReloc = 0 113 switch rt := r.Type(); rt { 114 case objabi.R_ADDRMIPS, objabi.R_ADDRMIPSU: 115 t := ldr.SymValue(rs) + r.Add() 116 return applyrel(target.Arch, ldr, rt, r.Off(), s, val, t), noExtReloc, isOk 117 case objabi.R_CALLMIPS, objabi.R_JMPMIPS: 118 t := ldr.SymValue(rs) + r.Add() 119 120 if t&3 != 0 { 121 ldr.Errorf(s, "direct call is not aligned: %s %x", ldr.SymName(rs), t) 122 } 123 124 // check if target address is in the same 256 MB region as the next instruction 125 if (ldr.SymValue(s)+int64(r.Off())+4)&0xf0000000 != (t & 0xf0000000) { 126 ldr.Errorf(s, "direct call too far: %s %x", ldr.SymName(rs), t) 127 } 128 129 return applyrel(target.Arch, ldr, rt, r.Off(), s, val, t), noExtReloc, isOk 130 case objabi.R_ADDRMIPSTLS: 131 // thread pointer is at 0x7000 offset from the start of TLS data area 132 t := ldr.SymValue(rs) + r.Add() - 0x7000 133 if t < -32768 || t >= 32678 { 134 ldr.Errorf(s, "TLS offset out of range %d", t) 135 } 136 return applyrel(target.Arch, ldr, rt, r.Off(), s, val, t), noExtReloc, isOk 137 } 138 139 return val, 0, false 140} 141 142func archrelocvariant(*ld.Target, *loader.Loader, loader.Reloc, sym.RelocVariant, loader.Sym, int64, []byte) int64 { 143 return -1 144} 145 146func extreloc(target *ld.Target, ldr *loader.Loader, r loader.Reloc, s loader.Sym) (loader.ExtReloc, bool) { 147 switch r.Type() { 148 case objabi.R_ADDRMIPS, objabi.R_ADDRMIPSU: 149 return ld.ExtrelocViaOuterSym(ldr, r, s), true 150 151 case objabi.R_ADDRMIPSTLS, objabi.R_CALLMIPS, objabi.R_JMPMIPS: 152 return ld.ExtrelocSimple(ldr, r), true 153 } 154 return loader.ExtReloc{}, false 155} 156