[ELF/AArch64] - Implemented R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 and R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC relocations

[grimar]

Summary

• R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 is calculated as Page(G(GTPREL(S+A))) – Page(P), set an ADRP immediate field to bits [32:12] of X; check –2^32 ≤ X < 2^32;
• R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC is calculated as G(GTPREL(S+A)), set an LD offset field to bits [11:3] of X. No overflow check; check that X&7 = 0.

[ruiu]

LGTM

ELF/Target.cpp

1280–1283 ↗

(On Diff #44649)

This is probably more readable as we have many expressions here.

switch (Type) {
case R_AARCH64_...:
case R_AARCH64_...:
case R_AARCH64_...:
case R_AARCH64_...:
  return true;
default:
 return relocNeedsPlt(Type, S);
}

[grimar]

ELF/Target.cpp

1280–1283 ↗

(On Diff #44649)

Done.

lld/trunk/ELF/Target.cpp

public:
   AArch64TargetInfo();
   unsigned getDynReloc(unsigned Type) const override;
   void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
   void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
                          uint64_t PltEntryAddr) const override;
   void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
                      uint64_t PltEntryAddr, int32_t Index,
                      unsigned RelOff) const override;
+  unsigned getTlsGotReloc(unsigned Type = -1) const override;
+  bool isTlsDynReloc(unsigned Type, const SymbolBody &S) const override;
   bool needsCopyRel(uint32_t Type, const SymbolBody &S) const override;
   bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
   bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
   void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P,
                    uint64_t SA, uint64_t ZA = 0,
                    uint8_t *PairedLoc = nullptr) const override;
 };
 
void PPC64TargetInfo::relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type,
   }
 }
 
 AArch64TargetInfo::AArch64TargetInfo() {
   CopyReloc = R_AARCH64_COPY;
   IRelativeReloc = R_AARCH64_IRELATIVE;
   GotReloc = R_AARCH64_GLOB_DAT;
   PltReloc = R_AARCH64_JUMP_SLOT;
+  TlsGotReloc = R_AARCH64_TLS_TPREL64;
   LazyRelocations = true;
   PltEntrySize = 16;
   PltZeroEntrySize = 32;
 }
 
 unsigned AArch64TargetInfo::getDynReloc(unsigned Type) const {
   if (Type == R_AARCH64_ABS32 || Type == R_AARCH64_ABS64)
     return Type;
void AArch64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
   relocateOne(Buf, Buf + 4, R_AARCH64_ADR_PREL_PG_HI21, PltEntryAddr,
               GotEntryAddr);
   relocateOne(Buf + 4, Buf + 8, R_AARCH64_LDST64_ABS_LO12_NC, PltEntryAddr + 4,
               GotEntryAddr);
   relocateOne(Buf + 8, Buf + 12, R_AARCH64_ADD_ABS_LO12_NC, PltEntryAddr + 8,
               GotEntryAddr);
 }
 
+unsigned AArch64TargetInfo::getTlsGotReloc(unsigned Type) const {
+  if (Type == R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 ||
+      Type == R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC)
+    return Type;
+  return TlsGotReloc;
+}
+
+bool AArch64TargetInfo::isTlsDynReloc(unsigned Type,
+                                      const SymbolBody &S) const {
+  return Type == R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 ||
+         Type == R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC;
+}
+
 bool AArch64TargetInfo::needsCopyRel(uint32_t Type, const SymbolBody &S) const {
   if (Config->Shared)
     return false;
   switch (Type) {
   default:
     return false;
   case R_AARCH64_ABS16:
   case R_AARCH64_ABS32:
   case R_AARCH64_ABS64:
   case R_AARCH64_ADD_ABS_LO12_NC:
   case R_AARCH64_ADR_PREL_LO21:
   case R_AARCH64_ADR_PREL_PG_HI21:
   case R_AARCH64_LDST8_ABS_LO12_NC:
   case R_AARCH64_LDST32_ABS_LO12_NC:
   case R_AARCH64_LDST64_ABS_LO12_NC:
     if (auto *SS = dyn_cast<SharedSymbol<ELF64LE>>(&S))
       return SS->Sym.getType() == STT_OBJECT;
     return false;
   }
 }
 
 bool AArch64TargetInfo::relocNeedsGot(uint32_t Type,
                                       const SymbolBody &S) const {
-  return Type == R_AARCH64_ADR_GOT_PAGE || Type == R_AARCH64_LD64_GOT_LO12_NC ||
-         relocNeedsPlt(Type, S);
+  switch (Type) {
+  case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
+  case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
+  case R_AARCH64_ADR_GOT_PAGE:
+  case R_AARCH64_LD64_GOT_LO12_NC:
+    return true;
+  default:
+    return relocNeedsPlt(Type, S);
+  }
 }
 
 bool AArch64TargetInfo::relocNeedsPlt(uint32_t Type,
                                       const SymbolBody &S) const {
   if (isGnuIFunc<ELF64LE>(S))
     return true;
   switch (Type) {
   default:
case R_AARCH64_ADR_GOT_PAGE: {
     break;
   }
   case R_AARCH64_ADR_PREL_LO21: {
     uint64_t X = SA - P;
     checkInt<21>(X, Type);
     updateAArch64Adr(Loc, X & 0x1FFFFF);
     break;
   }
-  case R_AARCH64_ADR_PREL_PG_HI21: {
+  case R_AARCH64_ADR_PREL_PG_HI21:
+  case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21: {
     uint64_t X = getAArch64Page(SA) - getAArch64Page(P);
     checkInt<33>(X, Type);
     updateAArch64Adr(Loc, (X >> 12) & 0x1FFFFF); // X[32:12]
     break;
   }
   case R_AARCH64_CALL26:
   case R_AARCH64_JUMP26: {
     uint64_t X = SA - P;
     checkInt<28>(X, Type);
     or32le(Loc, (X & 0x0FFFFFFC) >> 2);
     break;
   }
   case R_AARCH64_CONDBR19: {
     uint64_t X = SA - P;
     checkInt<21>(X, Type);
     or32le(Loc, (X & 0x1FFFFC) << 3);
     break;
   }
   case R_AARCH64_LD64_GOT_LO12_NC:
+  case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
     checkAlignment<8>(SA, Type);
     or32le(Loc, (SA & 0xFF8) << 7);
     break;
   case R_AARCH64_LDST8_ABS_LO12_NC:
     or32le(Loc, (SA & 0xFFF) << 10);
     break;
   case R_AARCH64_LDST32_ABS_LO12_NC:
     or32le(Loc, (SA & 0xFFC) << 8);

lld/trunk/test/ELF/aarch64-tls-ie.s

+# RUN: llvm-mc -filetype=obj -triple=aarch64-unknown-freebsd %p/Inputs/aarch64-tls-ie.s -o %tdso.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-unknown-freebsd %s -o %tmain.o
+# RUN: ld.lld -shared %tdso.o -o %tdso.so
+# RUN: ld.lld %tmain.o %tdso.so -o %tout
+# RUN: llvm-objdump -d %tout | FileCheck %s
+# RUN: llvm-readobj -s -r %tout | FileCheck -check-prefix=RELOC %s
+# REQUIRES: aarch64
+
+#RELOC:      Section {
+#RELOC:        Index:
+#RELOC:        Name: .got
+#RELOC-NEXT:   Type: SHT_PROGBITS
+#RELOC-NEXT:   Flags [
+#RELOC-NEXT:     SHF_ALLOC
+#RELOC-NEXT:     SHF_WRITE
+#RELOC-NEXT:   ]
+#RELOC-NEXT:   Address: 0x120B0
+#RELOC-NEXT:   Offset: 0x20B0
+#RELOC-NEXT:   Size: 16
+#RELOC-NEXT:   Link: 0
+#RELOC-NEXT:   Info: 0
+#RELOC-NEXT:   AddressAlignment: 8
+#RELOC-NEXT:   EntrySize: 0
+#RELOC-NEXT: }
+#RELOC:      Relocations [
+#RELOC-NEXT:  Section ({{.*}}) .rela.dyn {
+#RELOC-NEXT:    0x120B0 R_AARCH64_TLS_TPREL64 foo 0x0
+#RELOC-NEXT:    0x120B8 R_AARCH64_TLS_TPREL64 bar 0x0
+#RELOC-NEXT:  }
+#RELOC-NEXT:]
+
+# Page(0x120B0) - Page(0x11000) = 0x1000 = 4096
+# 0x120B0 & 0xff8 = 0xB0 = 176
+# Page(0x120B8) - Page(0x11000) = 0x1000 = 4096
+# 0x120B8 & 0xff8 = 0xB8 = 184
+#CHECK: Disassembly of section .text:
+#CHECK: _start:
+#CHECK:  11000: 00 00 00 b0 adrp x0, #4096
+#CHECK:  11004: 00 58 40 f9 ldr  x0, [x0, #176]
+#CHECK:  11008: 00 00 00 b0 adrp x0, #4096
+#CHECK:  1100c: 00 5c 40 f9 ldr  x0, [x0, #184]
+
+.globl _start
+_start:
+ adrp x0, :gottprel:foo
+ ldr x0, [x0, #:gottprel_lo12:foo]
+
+ adrp x0, :gottprel:bar
+ ldr x0, [x0, #:gottprel_lo12:bar]