1 //===- Relocations.h -------------------------------------------*- C++ -*-===//
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLD_ELF_RELOCATIONS_H
11 #define LLD_ELF_RELOCATIONS_H
13 #include "lld/Core/LLVM.h"
14 #include "llvm/ADT/DenseMap.h"
22 class InputSectionBase;
24 struct OutputSectionCommand;
26 // List of target-independent relocation types. Relocations read
27 // from files are converted to these types so that the main code
28 // doesn't have to know about architecture-specific details.
34 R_GOTONLY_PC_FROM_END,
45 R_MIPS_GOT_LOCAL_PAGE,
63 R_RELAX_TLS_GD_TO_IE_ABS,
64 R_RELAX_TLS_GD_TO_IE_END,
65 R_RELAX_TLS_GD_TO_IE_PAGE_PC,
67 R_RELAX_TLS_GD_TO_LE_NEG,
81 // Build a bitmask with one bit set for each RelExpr.
83 // Constexpr function arguments can't be used in static asserts, so we
84 // use template arguments to build the mask.
85 // But function template partial specializations don't exist (needed
86 // for base case of the recursion), so we need a dummy struct.
87 template <RelExpr... Exprs> struct RelExprMaskBuilder {
88 static inline uint64_t build() { return 0; }
91 // Specialization for recursive case.
92 template <RelExpr Head, RelExpr... Tail>
93 struct RelExprMaskBuilder<Head, Tail...> {
94 static inline uint64_t build() {
95 static_assert(0 <= Head && Head < 64,
96 "RelExpr is too large for 64-bit mask!");
97 return (uint64_t(1) << Head) | RelExprMaskBuilder<Tail...>::build();
101 // Return true if `Expr` is one of `Exprs`.
102 // There are fewer than 64 RelExpr's, so we can represent any set of
103 // RelExpr's as a constant bit mask and test for membership with a
104 // couple cheap bitwise operations.
105 template <RelExpr... Exprs> bool isRelExprOneOf(RelExpr Expr) {
106 assert(0 <= Expr && (int)Expr < 64 && "RelExpr is too large for 64-bit mask!");
107 return (uint64_t(1) << Expr) & RelExprMaskBuilder<Exprs...>::build();
110 // Architecture-neutral representation of relocation.
119 template <class ELFT> void scanRelocations(InputSectionBase &);
126 // Return true if Thunks have been added to OutputSections
127 bool createThunks(ArrayRef<OutputSectionCommand *> OutputSections);
131 ThunkSection *getOSThunkSec(OutputSection *OS,
132 std::vector<InputSection *> *ISR);
133 ThunkSection *getISThunkSec(InputSection *IS, OutputSection *OS);
134 void forEachExecInputSection(
135 ArrayRef<OutputSectionCommand *> OutputSections,
136 std::function<void(OutputSection *, std::vector<InputSection *> *,
139 std::pair<Thunk *, bool> getThunk(SymbolBody &Body, uint32_t Type);
141 // Track Symbols that already have a Thunk
142 llvm::DenseMap<SymbolBody *, Thunk *> ThunkedSymbols;
144 // Track InputSections that have a ThunkSection placed in front
145 llvm::DenseMap<InputSection *, ThunkSection *> ThunkedSections;
147 // Track the ThunksSections that need to be inserted into an OutputSection
148 std::map<std::vector<InputSection *> *, std::vector<ThunkSection *>>
151 // The ThunkSection for this vector of InputSections
155 // Return a int64_t to make sure we get the sign extension out of the way as
156 // early as possible.
157 template <class ELFT>
158 static inline int64_t getAddend(const typename ELFT::Rel &Rel) {
161 template <class ELFT>
162 static inline int64_t getAddend(const typename ELFT::Rela &Rel) {