747 lines
26 KiB
C++
747 lines
26 KiB
C++
//===---- MachO_x86_64.cpp -JIT linker implementation for MachO/x86-64 ----===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// MachO/x86-64 jit-link implementation.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/ExecutionEngine/JITLink/MachO_x86_64.h"
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#include "BasicGOTAndStubsBuilder.h"
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#include "MachOLinkGraphBuilder.h"
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#define DEBUG_TYPE "jitlink"
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using namespace llvm;
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using namespace llvm::jitlink;
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using namespace llvm::jitlink::MachO_x86_64_Edges;
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namespace {
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class MachOLinkGraphBuilder_x86_64 : public MachOLinkGraphBuilder {
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public:
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MachOLinkGraphBuilder_x86_64(const object::MachOObjectFile &Obj)
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: MachOLinkGraphBuilder(Obj, Triple("x86_64-apple-darwin")) {}
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private:
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static Expected<MachOX86RelocationKind>
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getRelocationKind(const MachO::relocation_info &RI) {
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switch (RI.r_type) {
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case MachO::X86_64_RELOC_UNSIGNED:
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if (!RI.r_pcrel) {
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if (RI.r_length == 3)
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return RI.r_extern ? Pointer64 : Pointer64Anon;
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else if (RI.r_extern && RI.r_length == 2)
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return Pointer32;
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}
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break;
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case MachO::X86_64_RELOC_SIGNED:
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if (RI.r_pcrel && RI.r_length == 2)
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return RI.r_extern ? PCRel32 : PCRel32Anon;
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break;
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case MachO::X86_64_RELOC_BRANCH:
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if (RI.r_pcrel && RI.r_extern && RI.r_length == 2)
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return Branch32;
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break;
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case MachO::X86_64_RELOC_GOT_LOAD:
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if (RI.r_pcrel && RI.r_extern && RI.r_length == 2)
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return PCRel32GOTLoad;
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break;
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case MachO::X86_64_RELOC_GOT:
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if (RI.r_pcrel && RI.r_extern && RI.r_length == 2)
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return PCRel32GOT;
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break;
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case MachO::X86_64_RELOC_SUBTRACTOR:
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// SUBTRACTOR must be non-pc-rel, extern, with length 2 or 3.
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// Initially represent SUBTRACTOR relocations with 'Delta<W>'. They may
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// be turned into NegDelta<W> by parsePairRelocation.
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if (!RI.r_pcrel && RI.r_extern) {
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if (RI.r_length == 2)
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return Delta32;
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else if (RI.r_length == 3)
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return Delta64;
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}
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break;
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case MachO::X86_64_RELOC_SIGNED_1:
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if (RI.r_pcrel && RI.r_length == 2)
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return RI.r_extern ? PCRel32Minus1 : PCRel32Minus1Anon;
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break;
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case MachO::X86_64_RELOC_SIGNED_2:
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if (RI.r_pcrel && RI.r_length == 2)
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return RI.r_extern ? PCRel32Minus2 : PCRel32Minus2Anon;
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break;
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case MachO::X86_64_RELOC_SIGNED_4:
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if (RI.r_pcrel && RI.r_length == 2)
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return RI.r_extern ? PCRel32Minus4 : PCRel32Minus4Anon;
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break;
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case MachO::X86_64_RELOC_TLV:
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if (RI.r_pcrel && RI.r_extern && RI.r_length == 2)
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return PCRel32TLV;
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break;
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}
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return make_error<JITLinkError>(
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"Unsupported x86-64 relocation: address=" +
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formatv("{0:x8}", RI.r_address) +
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", symbolnum=" + formatv("{0:x6}", RI.r_symbolnum) +
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", kind=" + formatv("{0:x1}", RI.r_type) +
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", pc_rel=" + (RI.r_pcrel ? "true" : "false") +
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", extern=" + (RI.r_extern ? "true" : "false") +
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", length=" + formatv("{0:d}", RI.r_length));
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}
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using PairRelocInfo = std::tuple<MachOX86RelocationKind, Symbol *, uint64_t>;
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// Parses paired SUBTRACTOR/UNSIGNED relocations and, on success,
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// returns the edge kind and addend to be used.
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Expected<PairRelocInfo>
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parsePairRelocation(Block &BlockToFix, Edge::Kind SubtractorKind,
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const MachO::relocation_info &SubRI,
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JITTargetAddress FixupAddress, const char *FixupContent,
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object::relocation_iterator &UnsignedRelItr,
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object::relocation_iterator &RelEnd) {
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using namespace support;
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assert(((SubtractorKind == Delta32 && SubRI.r_length == 2) ||
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(SubtractorKind == Delta64 && SubRI.r_length == 3)) &&
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"Subtractor kind should match length");
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assert(SubRI.r_extern && "SUBTRACTOR reloc symbol should be extern");
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assert(!SubRI.r_pcrel && "SUBTRACTOR reloc should not be PCRel");
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if (UnsignedRelItr == RelEnd)
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return make_error<JITLinkError>("x86_64 SUBTRACTOR without paired "
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"UNSIGNED relocation");
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auto UnsignedRI = getRelocationInfo(UnsignedRelItr);
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if (SubRI.r_address != UnsignedRI.r_address)
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return make_error<JITLinkError>("x86_64 SUBTRACTOR and paired UNSIGNED "
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"point to different addresses");
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if (SubRI.r_length != UnsignedRI.r_length)
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return make_error<JITLinkError>("length of x86_64 SUBTRACTOR and paired "
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"UNSIGNED reloc must match");
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Symbol *FromSymbol;
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if (auto FromSymbolOrErr = findSymbolByIndex(SubRI.r_symbolnum))
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FromSymbol = FromSymbolOrErr->GraphSymbol;
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else
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return FromSymbolOrErr.takeError();
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// Read the current fixup value.
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uint64_t FixupValue = 0;
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if (SubRI.r_length == 3)
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FixupValue = *(const little64_t *)FixupContent;
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else
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FixupValue = *(const little32_t *)FixupContent;
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// Find 'ToSymbol' using symbol number or address, depending on whether the
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// paired UNSIGNED relocation is extern.
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Symbol *ToSymbol = nullptr;
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if (UnsignedRI.r_extern) {
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// Find target symbol by symbol index.
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if (auto ToSymbolOrErr = findSymbolByIndex(UnsignedRI.r_symbolnum))
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ToSymbol = ToSymbolOrErr->GraphSymbol;
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else
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return ToSymbolOrErr.takeError();
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} else {
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auto ToSymbolSec = findSectionByIndex(UnsignedRI.r_symbolnum - 1);
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if (!ToSymbolSec)
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return ToSymbolSec.takeError();
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ToSymbol = getSymbolByAddress(ToSymbolSec->Address);
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assert(ToSymbol && "No symbol for section");
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FixupValue -= ToSymbol->getAddress();
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}
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MachOX86RelocationKind DeltaKind;
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Symbol *TargetSymbol;
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uint64_t Addend;
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if (&BlockToFix == &FromSymbol->getAddressable()) {
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TargetSymbol = ToSymbol;
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DeltaKind = (SubRI.r_length == 3) ? Delta64 : Delta32;
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Addend = FixupValue + (FixupAddress - FromSymbol->getAddress());
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// FIXME: handle extern 'from'.
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} else if (&BlockToFix == &ToSymbol->getAddressable()) {
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TargetSymbol = FromSymbol;
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DeltaKind = (SubRI.r_length == 3) ? NegDelta64 : NegDelta32;
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Addend = FixupValue - (FixupAddress - ToSymbol->getAddress());
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} else {
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// BlockToFix was neither FromSymbol nor ToSymbol.
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return make_error<JITLinkError>("SUBTRACTOR relocation must fix up "
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"either 'A' or 'B' (or a symbol in one "
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"of their alt-entry chains)");
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}
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return PairRelocInfo(DeltaKind, TargetSymbol, Addend);
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}
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Error addRelocations() override {
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using namespace support;
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auto &Obj = getObject();
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LLVM_DEBUG(dbgs() << "Processing relocations:\n");
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for (auto &S : Obj.sections()) {
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JITTargetAddress SectionAddress = S.getAddress();
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// Skip relocations virtual sections.
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if (S.isVirtual()) {
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if (S.relocation_begin() != S.relocation_end())
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return make_error<JITLinkError>("Virtual section contains "
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"relocations");
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continue;
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}
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// Skip relocations for debug symbols.
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{
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auto &NSec =
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getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl()));
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if (!NSec.GraphSection) {
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LLVM_DEBUG({
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dbgs() << " Skipping relocations for MachO section "
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<< NSec.SegName << "/" << NSec.SectName
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<< " which has no associated graph section\n";
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});
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continue;
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}
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}
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// Add relocations for section.
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for (auto RelItr = S.relocation_begin(), RelEnd = S.relocation_end();
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RelItr != RelEnd; ++RelItr) {
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MachO::relocation_info RI = getRelocationInfo(RelItr);
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// Sanity check the relocation kind.
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auto Kind = getRelocationKind(RI);
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if (!Kind)
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return Kind.takeError();
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// Find the address of the value to fix up.
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JITTargetAddress FixupAddress = SectionAddress + (uint32_t)RI.r_address;
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LLVM_DEBUG({
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auto &NSec =
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getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl()));
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dbgs() << " " << NSec.SectName << " + "
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<< formatv("{0:x8}", RI.r_address) << ":\n";
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});
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// Find the block that the fixup points to.
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Block *BlockToFix = nullptr;
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{
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auto SymbolToFixOrErr = findSymbolByAddress(FixupAddress);
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if (!SymbolToFixOrErr)
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return SymbolToFixOrErr.takeError();
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BlockToFix = &SymbolToFixOrErr->getBlock();
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}
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if (FixupAddress + static_cast<JITTargetAddress>(1ULL << RI.r_length) >
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BlockToFix->getAddress() + BlockToFix->getContent().size())
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return make_error<JITLinkError>(
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"Relocation extends past end of fixup block");
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// Get a pointer to the fixup content.
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const char *FixupContent = BlockToFix->getContent().data() +
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(FixupAddress - BlockToFix->getAddress());
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// The target symbol and addend will be populated by the switch below.
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Symbol *TargetSymbol = nullptr;
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uint64_t Addend = 0;
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switch (*Kind) {
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case Branch32:
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case PCRel32:
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case PCRel32GOTLoad:
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case PCRel32GOT:
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if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum))
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TargetSymbol = TargetSymbolOrErr->GraphSymbol;
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else
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return TargetSymbolOrErr.takeError();
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Addend = *(const little32_t *)FixupContent;
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break;
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case Pointer32:
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if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum))
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TargetSymbol = TargetSymbolOrErr->GraphSymbol;
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else
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return TargetSymbolOrErr.takeError();
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Addend = *(const ulittle32_t *)FixupContent;
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break;
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case Pointer64:
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if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum))
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TargetSymbol = TargetSymbolOrErr->GraphSymbol;
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else
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return TargetSymbolOrErr.takeError();
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Addend = *(const ulittle64_t *)FixupContent;
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break;
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case Pointer64Anon: {
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JITTargetAddress TargetAddress = *(const ulittle64_t *)FixupContent;
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if (auto TargetSymbolOrErr = findSymbolByAddress(TargetAddress))
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TargetSymbol = &*TargetSymbolOrErr;
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else
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return TargetSymbolOrErr.takeError();
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Addend = TargetAddress - TargetSymbol->getAddress();
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break;
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}
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case PCRel32Minus1:
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case PCRel32Minus2:
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case PCRel32Minus4:
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if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum))
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TargetSymbol = TargetSymbolOrErr->GraphSymbol;
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else
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return TargetSymbolOrErr.takeError();
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Addend = *(const little32_t *)FixupContent +
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(1 << (*Kind - PCRel32Minus1));
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break;
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case PCRel32Anon: {
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JITTargetAddress TargetAddress =
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FixupAddress + 4 + *(const little32_t *)FixupContent;
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if (auto TargetSymbolOrErr = findSymbolByAddress(TargetAddress))
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TargetSymbol = &*TargetSymbolOrErr;
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else
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return TargetSymbolOrErr.takeError();
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Addend = TargetAddress - TargetSymbol->getAddress();
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break;
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}
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case PCRel32Minus1Anon:
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case PCRel32Minus2Anon:
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case PCRel32Minus4Anon: {
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JITTargetAddress Delta =
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static_cast<JITTargetAddress>(1ULL << (*Kind - PCRel32Minus1Anon));
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JITTargetAddress TargetAddress =
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FixupAddress + 4 + Delta + *(const little32_t *)FixupContent;
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if (auto TargetSymbolOrErr = findSymbolByAddress(TargetAddress))
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TargetSymbol = &*TargetSymbolOrErr;
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else
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return TargetSymbolOrErr.takeError();
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Addend = TargetAddress - TargetSymbol->getAddress();
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break;
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}
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case Delta32:
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case Delta64: {
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// We use Delta32/Delta64 to represent SUBTRACTOR relocations.
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// parsePairRelocation handles the paired reloc, and returns the
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// edge kind to be used (either Delta32/Delta64, or
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// NegDelta32/NegDelta64, depending on the direction of the
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// subtraction) along with the addend.
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auto PairInfo =
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parsePairRelocation(*BlockToFix, *Kind, RI, FixupAddress,
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FixupContent, ++RelItr, RelEnd);
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if (!PairInfo)
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return PairInfo.takeError();
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std::tie(*Kind, TargetSymbol, Addend) = *PairInfo;
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assert(TargetSymbol && "No target symbol from parsePairRelocation?");
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break;
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}
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case PCRel32TLV:
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return make_error<JITLinkError>(
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"MachO TLV relocations not yet supported");
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default:
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llvm_unreachable("Special relocation kind should not appear in "
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"mach-o file");
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}
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LLVM_DEBUG({
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dbgs() << " ";
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Edge GE(*Kind, FixupAddress - BlockToFix->getAddress(), *TargetSymbol,
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Addend);
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printEdge(dbgs(), *BlockToFix, GE,
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getMachOX86RelocationKindName(*Kind));
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dbgs() << "\n";
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});
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BlockToFix->addEdge(*Kind, FixupAddress - BlockToFix->getAddress(),
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*TargetSymbol, Addend);
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}
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}
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return Error::success();
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}
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};
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class MachO_x86_64_GOTAndStubsBuilder
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: public BasicGOTAndStubsBuilder<MachO_x86_64_GOTAndStubsBuilder> {
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public:
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static const uint8_t NullGOTEntryContent[8];
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static const uint8_t StubContent[6];
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MachO_x86_64_GOTAndStubsBuilder(LinkGraph &G)
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: BasicGOTAndStubsBuilder<MachO_x86_64_GOTAndStubsBuilder>(G) {}
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bool isGOTEdge(Edge &E) const {
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return E.getKind() == PCRel32GOT || E.getKind() == PCRel32GOTLoad;
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}
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Symbol &createGOTEntry(Symbol &Target) {
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auto &GOTEntryBlock = G.createContentBlock(
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getGOTSection(), getGOTEntryBlockContent(), 0, 8, 0);
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GOTEntryBlock.addEdge(Pointer64, 0, Target, 0);
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return G.addAnonymousSymbol(GOTEntryBlock, 0, 8, false, false);
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}
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void fixGOTEdge(Edge &E, Symbol &GOTEntry) {
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assert((E.getKind() == PCRel32GOT || E.getKind() == PCRel32GOTLoad) &&
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"Not a GOT edge?");
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// If this is a PCRel32GOT then change it to an ordinary PCRel32. If it is
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// a PCRel32GOTLoad then leave it as-is for now. We will use the kind to
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// check for GOT optimization opportunities in the
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// optimizeMachO_x86_64_GOTAndStubs pass below.
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if (E.getKind() == PCRel32GOT)
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E.setKind(PCRel32);
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E.setTarget(GOTEntry);
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// Leave the edge addend as-is.
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}
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bool isExternalBranchEdge(Edge &E) {
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return E.getKind() == Branch32 && !E.getTarget().isDefined();
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}
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Symbol &createStub(Symbol &Target) {
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auto &StubContentBlock =
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G.createContentBlock(getStubsSection(), getStubBlockContent(), 0, 1, 0);
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// Re-use GOT entries for stub targets.
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auto &GOTEntrySymbol = getGOTEntrySymbol(Target);
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StubContentBlock.addEdge(PCRel32, 2, GOTEntrySymbol, 0);
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return G.addAnonymousSymbol(StubContentBlock, 0, 6, true, false);
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}
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void fixExternalBranchEdge(Edge &E, Symbol &Stub) {
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assert(E.getKind() == Branch32 && "Not a Branch32 edge?");
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assert(E.getAddend() == 0 && "Branch32 edge has non-zero addend?");
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// Set the edge kind to Branch32ToStub. We will use this to check for stub
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// optimization opportunities in the optimizeMachO_x86_64_GOTAndStubs pass
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// below.
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E.setKind(Branch32ToStub);
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E.setTarget(Stub);
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}
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private:
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Section &getGOTSection() {
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if (!GOTSection)
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GOTSection = &G.createSection("$__GOT", sys::Memory::MF_READ);
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return *GOTSection;
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}
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Section &getStubsSection() {
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if (!StubsSection) {
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auto StubsProt = static_cast<sys::Memory::ProtectionFlags>(
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sys::Memory::MF_READ | sys::Memory::MF_EXEC);
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StubsSection = &G.createSection("$__STUBS", StubsProt);
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}
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return *StubsSection;
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}
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StringRef getGOTEntryBlockContent() {
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return StringRef(reinterpret_cast<const char *>(NullGOTEntryContent),
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sizeof(NullGOTEntryContent));
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}
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StringRef getStubBlockContent() {
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return StringRef(reinterpret_cast<const char *>(StubContent),
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sizeof(StubContent));
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}
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Section *GOTSection = nullptr;
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Section *StubsSection = nullptr;
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};
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const uint8_t MachO_x86_64_GOTAndStubsBuilder::NullGOTEntryContent[8] = {
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0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
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const uint8_t MachO_x86_64_GOTAndStubsBuilder::StubContent[6] = {
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0xFF, 0x25, 0x00, 0x00, 0x00, 0x00};
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} // namespace
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static Error optimizeMachO_x86_64_GOTAndStubs(LinkGraph &G) {
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LLVM_DEBUG(dbgs() << "Optimizing GOT entries and stubs:\n");
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for (auto *B : G.blocks())
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for (auto &E : B->edges())
|
|
if (E.getKind() == PCRel32GOTLoad) {
|
|
assert(E.getOffset() >= 3 && "GOT edge occurs too early in block");
|
|
|
|
// Switch the edge kind to PCRel32: Whether we change the edge target
|
|
// or not this will be the desired kind.
|
|
E.setKind(PCRel32);
|
|
|
|
// Optimize GOT references.
|
|
auto &GOTBlock = E.getTarget().getBlock();
|
|
assert(GOTBlock.getSize() == G.getPointerSize() &&
|
|
"GOT entry block should be pointer sized");
|
|
assert(GOTBlock.edges_size() == 1 &&
|
|
"GOT entry should only have one outgoing edge");
|
|
|
|
auto &GOTTarget = GOTBlock.edges().begin()->getTarget();
|
|
JITTargetAddress EdgeAddr = B->getAddress() + E.getOffset();
|
|
JITTargetAddress TargetAddr = GOTTarget.getAddress();
|
|
|
|
// Check that this is a recognized MOV instruction.
|
|
// FIXME: Can we assume this?
|
|
constexpr uint8_t MOVQRIPRel[] = {0x48, 0x8b};
|
|
if (strncmp(B->getContent().data() + E.getOffset() - 3,
|
|
reinterpret_cast<const char *>(MOVQRIPRel), 2) != 0)
|
|
continue;
|
|
|
|
int64_t Displacement = TargetAddr - EdgeAddr + 4;
|
|
if (Displacement >= std::numeric_limits<int32_t>::min() &&
|
|
Displacement <= std::numeric_limits<int32_t>::max()) {
|
|
E.setTarget(GOTTarget);
|
|
auto *BlockData = reinterpret_cast<uint8_t *>(
|
|
const_cast<char *>(B->getContent().data()));
|
|
BlockData[E.getOffset() - 2] = 0x8d;
|
|
LLVM_DEBUG({
|
|
dbgs() << " Replaced GOT load wih LEA:\n ";
|
|
printEdge(dbgs(), *B, E,
|
|
getMachOX86RelocationKindName(E.getKind()));
|
|
dbgs() << "\n";
|
|
});
|
|
}
|
|
} else if (E.getKind() == Branch32ToStub) {
|
|
|
|
// Switch the edge kind to PCRel32: Whether we change the edge target
|
|
// or not this will be the desired kind.
|
|
E.setKind(Branch32);
|
|
|
|
auto &StubBlock = E.getTarget().getBlock();
|
|
assert(StubBlock.getSize() ==
|
|
sizeof(MachO_x86_64_GOTAndStubsBuilder::StubContent) &&
|
|
"Stub block should be stub sized");
|
|
assert(StubBlock.edges_size() == 1 &&
|
|
"Stub block should only have one outgoing edge");
|
|
|
|
auto &GOTBlock = StubBlock.edges().begin()->getTarget().getBlock();
|
|
assert(GOTBlock.getSize() == G.getPointerSize() &&
|
|
"GOT block should be pointer sized");
|
|
assert(GOTBlock.edges_size() == 1 &&
|
|
"GOT block should only have one outgoing edge");
|
|
|
|
auto &GOTTarget = GOTBlock.edges().begin()->getTarget();
|
|
JITTargetAddress EdgeAddr = B->getAddress() + E.getOffset();
|
|
JITTargetAddress TargetAddr = GOTTarget.getAddress();
|
|
|
|
int64_t Displacement = TargetAddr - EdgeAddr + 4;
|
|
if (Displacement >= std::numeric_limits<int32_t>::min() &&
|
|
Displacement <= std::numeric_limits<int32_t>::max()) {
|
|
E.setTarget(GOTTarget);
|
|
LLVM_DEBUG({
|
|
dbgs() << " Replaced stub branch with direct branch:\n ";
|
|
printEdge(dbgs(), *B, E,
|
|
getMachOX86RelocationKindName(E.getKind()));
|
|
dbgs() << "\n";
|
|
});
|
|
}
|
|
}
|
|
|
|
return Error::success();
|
|
}
|
|
|
|
namespace llvm {
|
|
namespace jitlink {
|
|
|
|
class MachOJITLinker_x86_64 : public JITLinker<MachOJITLinker_x86_64> {
|
|
friend class JITLinker<MachOJITLinker_x86_64>;
|
|
|
|
public:
|
|
MachOJITLinker_x86_64(std::unique_ptr<JITLinkContext> Ctx,
|
|
std::unique_ptr<LinkGraph> G,
|
|
PassConfiguration PassConfig)
|
|
: JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {}
|
|
|
|
private:
|
|
StringRef getEdgeKindName(Edge::Kind R) const override {
|
|
return getMachOX86RelocationKindName(R);
|
|
}
|
|
|
|
static Error targetOutOfRangeError(const Block &B, const Edge &E) {
|
|
std::string ErrMsg;
|
|
{
|
|
raw_string_ostream ErrStream(ErrMsg);
|
|
ErrStream << "Relocation target out of range: ";
|
|
printEdge(ErrStream, B, E, getMachOX86RelocationKindName(E.getKind()));
|
|
ErrStream << "\n";
|
|
}
|
|
return make_error<JITLinkError>(std::move(ErrMsg));
|
|
}
|
|
|
|
Error applyFixup(Block &B, const Edge &E, char *BlockWorkingMem) const {
|
|
|
|
using namespace support;
|
|
|
|
char *FixupPtr = BlockWorkingMem + E.getOffset();
|
|
JITTargetAddress FixupAddress = B.getAddress() + E.getOffset();
|
|
|
|
switch (E.getKind()) {
|
|
case Branch32:
|
|
case PCRel32:
|
|
case PCRel32Anon: {
|
|
int64_t Value =
|
|
E.getTarget().getAddress() - (FixupAddress + 4) + E.getAddend();
|
|
if (Value < std::numeric_limits<int32_t>::min() ||
|
|
Value > std::numeric_limits<int32_t>::max())
|
|
return targetOutOfRangeError(B, E);
|
|
*(little32_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
case Pointer64:
|
|
case Pointer64Anon: {
|
|
uint64_t Value = E.getTarget().getAddress() + E.getAddend();
|
|
*(ulittle64_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
case PCRel32Minus1:
|
|
case PCRel32Minus2:
|
|
case PCRel32Minus4: {
|
|
int Delta = 4 + (1 << (E.getKind() - PCRel32Minus1));
|
|
int64_t Value =
|
|
E.getTarget().getAddress() - (FixupAddress + Delta) + E.getAddend();
|
|
if (Value < std::numeric_limits<int32_t>::min() ||
|
|
Value > std::numeric_limits<int32_t>::max())
|
|
return targetOutOfRangeError(B, E);
|
|
*(little32_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
case PCRel32Minus1Anon:
|
|
case PCRel32Minus2Anon:
|
|
case PCRel32Minus4Anon: {
|
|
int Delta = 4 + (1 << (E.getKind() - PCRel32Minus1Anon));
|
|
int64_t Value =
|
|
E.getTarget().getAddress() - (FixupAddress + Delta) + E.getAddend();
|
|
if (Value < std::numeric_limits<int32_t>::min() ||
|
|
Value > std::numeric_limits<int32_t>::max())
|
|
return targetOutOfRangeError(B, E);
|
|
*(little32_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
case Delta32:
|
|
case Delta64:
|
|
case NegDelta32:
|
|
case NegDelta64: {
|
|
int64_t Value;
|
|
if (E.getKind() == Delta32 || E.getKind() == Delta64)
|
|
Value = E.getTarget().getAddress() - FixupAddress + E.getAddend();
|
|
else
|
|
Value = FixupAddress - E.getTarget().getAddress() + E.getAddend();
|
|
|
|
if (E.getKind() == Delta32 || E.getKind() == NegDelta32) {
|
|
if (Value < std::numeric_limits<int32_t>::min() ||
|
|
Value > std::numeric_limits<int32_t>::max())
|
|
return targetOutOfRangeError(B, E);
|
|
*(little32_t *)FixupPtr = Value;
|
|
} else
|
|
*(little64_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
case Pointer32: {
|
|
uint64_t Value = E.getTarget().getAddress() + E.getAddend();
|
|
if (Value > std::numeric_limits<uint32_t>::max())
|
|
return targetOutOfRangeError(B, E);
|
|
*(ulittle32_t *)FixupPtr = Value;
|
|
break;
|
|
}
|
|
default:
|
|
llvm_unreachable("Unrecognized edge kind");
|
|
}
|
|
|
|
return Error::success();
|
|
}
|
|
|
|
uint64_t NullValue = 0;
|
|
};
|
|
|
|
Expected<std::unique_ptr<LinkGraph>>
|
|
createLinkGraphFromMachOObject_x86_64(MemoryBufferRef ObjectBuffer) {
|
|
auto MachOObj = object::ObjectFile::createMachOObjectFile(ObjectBuffer);
|
|
if (!MachOObj)
|
|
return MachOObj.takeError();
|
|
return MachOLinkGraphBuilder_x86_64(**MachOObj).buildGraph();
|
|
}
|
|
|
|
void link_MachO_x86_64(std::unique_ptr<LinkGraph> G,
|
|
std::unique_ptr<JITLinkContext> Ctx) {
|
|
|
|
PassConfiguration Config;
|
|
|
|
if (Ctx->shouldAddDefaultTargetPasses(G->getTargetTriple())) {
|
|
// Add eh-frame passses.
|
|
Config.PrePrunePasses.push_back(EHFrameSplitter("__eh_frame"));
|
|
Config.PrePrunePasses.push_back(EHFrameEdgeFixer(
|
|
"__eh_frame", G->getPointerSize(), Delta64, Delta32, NegDelta32));
|
|
|
|
// Add a mark-live pass.
|
|
if (auto MarkLive = Ctx->getMarkLivePass(G->getTargetTriple()))
|
|
Config.PrePrunePasses.push_back(std::move(MarkLive));
|
|
else
|
|
Config.PrePrunePasses.push_back(markAllSymbolsLive);
|
|
|
|
// Add an in-place GOT/Stubs pass.
|
|
Config.PostPrunePasses.push_back([](LinkGraph &G) -> Error {
|
|
MachO_x86_64_GOTAndStubsBuilder(G).run();
|
|
return Error::success();
|
|
});
|
|
|
|
// Add GOT/Stubs optimizer pass.
|
|
Config.PreFixupPasses.push_back(optimizeMachO_x86_64_GOTAndStubs);
|
|
}
|
|
|
|
if (auto Err = Ctx->modifyPassConfig(G->getTargetTriple(), Config))
|
|
return Ctx->notifyFailed(std::move(Err));
|
|
|
|
// Construct a JITLinker and run the link function.
|
|
MachOJITLinker_x86_64::link(std::move(Ctx), std::move(G), std::move(Config));
|
|
}
|
|
|
|
StringRef getMachOX86RelocationKindName(Edge::Kind R) {
|
|
switch (R) {
|
|
case Branch32:
|
|
return "Branch32";
|
|
case Branch32ToStub:
|
|
return "Branch32ToStub";
|
|
case Pointer32:
|
|
return "Pointer32";
|
|
case Pointer64:
|
|
return "Pointer64";
|
|
case Pointer64Anon:
|
|
return "Pointer64Anon";
|
|
case PCRel32:
|
|
return "PCRel32";
|
|
case PCRel32Minus1:
|
|
return "PCRel32Minus1";
|
|
case PCRel32Minus2:
|
|
return "PCRel32Minus2";
|
|
case PCRel32Minus4:
|
|
return "PCRel32Minus4";
|
|
case PCRel32Anon:
|
|
return "PCRel32Anon";
|
|
case PCRel32Minus1Anon:
|
|
return "PCRel32Minus1Anon";
|
|
case PCRel32Minus2Anon:
|
|
return "PCRel32Minus2Anon";
|
|
case PCRel32Minus4Anon:
|
|
return "PCRel32Minus4Anon";
|
|
case PCRel32GOTLoad:
|
|
return "PCRel32GOTLoad";
|
|
case PCRel32GOT:
|
|
return "PCRel32GOT";
|
|
case PCRel32TLV:
|
|
return "PCRel32TLV";
|
|
case Delta32:
|
|
return "Delta32";
|
|
case Delta64:
|
|
return "Delta64";
|
|
case NegDelta32:
|
|
return "NegDelta32";
|
|
case NegDelta64:
|
|
return "NegDelta64";
|
|
default:
|
|
return getGenericEdgeKindName(static_cast<Edge::Kind>(R));
|
|
}
|
|
}
|
|
|
|
} // end namespace jitlink
|
|
} // end namespace llvm
|