ELF: Add support for R_AARCH64_ADR_PREL_PG_HI21_NC relocation.

[pcc]

Summary

Depends on D64455

[MaskRay]

Might be worth adding another test to aarch64-fpic-adr_prel_pg_hi21.s

[pcc]

• Address review comments

[pcc]

In D64456#1577531, @MaskRay wrote:

Might be worth adding another test to aarch64-fpic-adr_prel_pg_hi21.s

Makes sense, done.

[peter.smith]

I've accepted D64455, looks good to me too.

[ruiu]

LGTM

lld/ELF/Arch/AArch64.cpp

case R_AARCH64_TSTBR14:
     return R_PLT_PC;
   case R_AARCH64_PREL16:
   case R_AARCH64_PREL32:
   case R_AARCH64_PREL64:
   case R_AARCH64_ADR_PREL_LO21:
   case R_AARCH64_LD_PREL_LO19:
     return R_PC;
   case R_AARCH64_ADR_PREL_PG_HI21:
+  case R_AARCH64_ADR_PREL_PG_HI21_NC:
     return R_AARCH64_PAGE_PC;
   case R_AARCH64_LD64_GOT_LO12_NC:
   case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
     return R_GOT;
   case R_AARCH64_ADR_GOT_PAGE:
   case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
     return R_AARCH64_GOT_PAGE_PC;
   case R_AARCH64_NONE:
void AArch64::relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const {
   case R_AARCH64_ADD_ABS_LO12_NC:
     or32AArch64Imm(Loc, Val);
     break;
   case R_AARCH64_ADR_GOT_PAGE:
   case R_AARCH64_ADR_PREL_PG_HI21:
   case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
   case R_AARCH64_TLSDESC_ADR_PAGE21:
     checkInt(Loc, Val, 33, Type);
+    LLVM_FALLTHROUGH;
+  case R_AARCH64_ADR_PREL_PG_HI21_NC:
     write32AArch64Addr(Loc, Val >> 12);
     break;
   case R_AARCH64_ADR_PREL_LO21:
     checkInt(Loc, Val, 21, Type);
     write32AArch64Addr(Loc, Val);
     break;
   case R_AARCH64_JUMP26:
     // Normally we would just write the bits of the immediate field, however

lld/test/ELF/aarch64-fpic-adr_prel_pg_hi21.s

 // REQUIRES: aarch64
 // RUN: llvm-mc -filetype=obj -triple=aarch64-none-freebsd %s -o %t.o
 // RUN: not ld.lld -shared %t.o -o /dev/null 2>&1 | FileCheck %s
 // CHECK: relocation R_AARCH64_ADR_PREL_PG_HI21 cannot be used against symbol dat; recompile with -fPIC
 // CHECK: >>> defined in {{.*}}.o
 // CHECK: >>> referenced by {{.*}}.o:(.text+0x0)
+// CHECK: relocation R_AARCH64_ADR_PREL_PG_HI21_NC cannot be used against symbol dat; recompile with -fPIC
 
   adrp x0, dat
+  adrp x0, :pg_hi21_nc:dat
 .data
 .globl dat
 dat:
   .word 0

lld/test/ELF/aarch64-hi21-nc.s

+// REQUIRES: aarch64
+// RUN: llvm-mc -filetype=obj -triple=aarch64-unknown-linux %s -o %t.o
+// RUN: ld.lld %t.o -o %t
+// RUN: llvm-objdump -d %t | FileCheck %s
+
+foo = . + 0x1100000000000000
+// CHECK: adrp x0, #0
+adrp x0, :pg_hi21_nc:foo