1 //===- AMDGPU.cpp ---------------------------------------------------------===//
2 //
3 //                             The LLVM Linker
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "InputFiles.h"
11 #include "Symbols.h"
12 #include "Target.h"
13 #include "lld/Common/ErrorHandler.h"
14 #include "llvm/Object/ELF.h"
15 #include "llvm/Support/Endian.h"
16 
17 using namespace llvm;
18 using namespace llvm::object;
19 using namespace llvm::support::endian;
20 using namespace llvm::ELF;
21 using namespace lld;
22 using namespace lld::elf;
23 
24 namespace {
25 class AMDGPU final : public TargetInfo {
26 public:
27   AMDGPU();
28   uint32_t calcEFlags() const override;
29   void relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const override;
30   RelExpr getRelExpr(RelType Type, const Symbol &S,
31                      const uint8_t *Loc) const override;
32 };
33 } // namespace
34 
AMDGPU()35 AMDGPU::AMDGPU() {
36   RelativeRel = R_AMDGPU_RELATIVE64;
37   GotRel = R_AMDGPU_ABS64;
38   NoneRel = R_AMDGPU_NONE;
39   GotEntrySize = 8;
40 }
41 
getEFlags(InputFile * File)42 static uint32_t getEFlags(InputFile *File) {
43   return cast<ObjFile<ELF64LE>>(File)->getObj().getHeader()->e_flags;
44 }
45 
calcEFlags() const46 uint32_t AMDGPU::calcEFlags() const {
47   assert(!ObjectFiles.empty());
48   uint32_t Ret = getEFlags(ObjectFiles[0]);
49 
50   // Verify that all input files have the same e_flags.
51   for (InputFile *F : makeArrayRef(ObjectFiles).slice(1)) {
52     if (Ret == getEFlags(F))
53       continue;
54     error("incompatible e_flags: " + toString(F));
55     return 0;
56   }
57   return Ret;
58 }
59 
relocateOne(uint8_t * Loc,RelType Type,uint64_t Val) const60 void AMDGPU::relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const {
61   switch (Type) {
62   case R_AMDGPU_ABS32:
63   case R_AMDGPU_GOTPCREL:
64   case R_AMDGPU_GOTPCREL32_LO:
65   case R_AMDGPU_REL32:
66   case R_AMDGPU_REL32_LO:
67     write32le(Loc, Val);
68     break;
69   case R_AMDGPU_ABS64:
70   case R_AMDGPU_REL64:
71     write64le(Loc, Val);
72     break;
73   case R_AMDGPU_GOTPCREL32_HI:
74   case R_AMDGPU_REL32_HI:
75     write32le(Loc, Val >> 32);
76     break;
77   default:
78     error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type));
79   }
80 }
81 
getRelExpr(RelType Type,const Symbol & S,const uint8_t * Loc) const82 RelExpr AMDGPU::getRelExpr(RelType Type, const Symbol &S,
83                            const uint8_t *Loc) const {
84   switch (Type) {
85   case R_AMDGPU_ABS32:
86   case R_AMDGPU_ABS64:
87     return R_ABS;
88   case R_AMDGPU_REL32:
89   case R_AMDGPU_REL32_LO:
90   case R_AMDGPU_REL32_HI:
91   case R_AMDGPU_REL64:
92     return R_PC;
93   case R_AMDGPU_GOTPCREL:
94   case R_AMDGPU_GOTPCREL32_LO:
95   case R_AMDGPU_GOTPCREL32_HI:
96     return R_GOT_PC;
97   default:
98     return R_INVALID;
99   }
100 }
101 
getAMDGPUTargetInfo()102 TargetInfo *elf::getAMDGPUTargetInfo() {
103   static AMDGPU Target;
104   return &Target;
105 }
106