[PATCH] D38053: [AArch64] Implement R_AARCH64_ LD_PREL_LO19

[Rafael Avila de Espindola via llvm-commits]

LGTM

Thanks

Davide Italiano via Phabricator <reviews at reviews.llvm.org> writes:

> davide updated this revision to Diff 115907.
> davide added a comment.
>
> Rafael's comments.
>
>
> https://reviews.llvm.org/D38053
>
> Files:
>   ELF/Arch/AArch64.cpp
>   ELF/InputSection.cpp
>   test/ELF/aarch64-undefined-weak.s
>   test/ELF/pr34660.s
>
>
> Index: test/ELF/pr34660.s
> ===================================================================
> --- /dev/null
> +++ test/ELF/pr34660.s
> @@ -0,0 +1,25 @@
> +# REQUIRES: aarch64
> +
> +# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-none %s -o %t.o
> +# RUN: ld.lld -shared %t.o -o %t
> +# RUN: llvm-objdump %t -d | FileCheck %s --check-prefix=DISASM
> +# RUN: llvm-readobj -elf-output-style=GNU %t -t | FileCheck %s --check-prefix=SYM
> +
> +# It would be much easier to understand/read this test if llvm-objdump would print
> +# the immediates in hex.
> +# IMM = hex(65540) = 0x10004
> +# PC = 0x10000
> +# As the relocation is PC-relative, IMM + PC = 0x20004 which is the VA of the
> +# correct symbol.
> +
> +# DISASM: Disassembly of section .text:
> +# DISASM-NEXT: $x.0:
> +# DISASM-NEXT:   10000:       28 00 08 58     ldr     x8, #65540
> +
> +# SYM: Symbol table '.symtab'
> +# SYM:  0000000000020004     0 NOTYPE  LOCAL  DEFAULT    5 patatino
> +
> +  ldr x8, patatino
> +  .data
> +  .zero 4
> +patatino:
> Index: test/ELF/aarch64-undefined-weak.s
> ===================================================================
> --- test/ELF/aarch64-undefined-weak.s
> +++ test/ELF/aarch64-undefined-weak.s
> @@ -30,6 +30,8 @@
>   .xword target - .
>  // R_AARCH64_PREL16
>   .hword target - .
> +// R_AARCH64_LD_PREL_LO19
> + ldr x8, target
>  
>  // CHECK: Disassembly of section .text:
>  // 131076 = 0x20004
> @@ -43,3 +45,5 @@
>  // CHECK-NEXT:    2001c: {{.*}} .word   0x00000000
>  // CHECK-NEXT:    20020: {{.*}} .word   0x00000000
>  // CHECK-NEXT:    20024: {{.*}} .short  0x0000
> +// CHECK:         $x.2:
> +// CHECK-NEXT:    20026: {{.*}} ldr     x8, #0
> Index: ELF/InputSection.cpp
> ===================================================================
> --- ELF/InputSection.cpp
> +++ ELF/InputSection.cpp
> @@ -471,6 +471,7 @@
>    case R_AARCH64_PREL32:
>    case R_AARCH64_PREL64:
>    case R_AARCH64_ADR_PREL_LO21:
> +  case R_AARCH64_LD_PREL_LO19:
>      return P + A;
>    }
>    llvm_unreachable("AArch64 pc-relative relocation expected\n");
> Index: ELF/Arch/AArch64.cpp
> ===================================================================
> --- ELF/Arch/AArch64.cpp
> +++ ELF/Arch/AArch64.cpp
> @@ -92,6 +92,7 @@
>    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:
>      return R_PAGE_PC;
> @@ -247,6 +248,7 @@
>      or32le(Loc, (Val & 0x0FFFFFFC) >> 2);
>      break;
>    case R_AARCH64_CONDBR19:
> +  case R_AARCH64_LD_PREL_LO19:
>      checkInt<21>(Loc, Val, Type);
>      or32le(Loc, (Val & 0x1FFFFC) << 3);
>      break;
>
>
> Index: test/ELF/pr34660.s
> ===================================================================
> --- /dev/null
> +++ test/ELF/pr34660.s
> @@ -0,0 +1,25 @@
> +# REQUIRES: aarch64
> +
> +# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-none %s -o %t.o
> +# RUN: ld.lld -shared %t.o -o %t
> +# RUN: llvm-objdump %t -d | FileCheck %s --check-prefix=DISASM
> +# RUN: llvm-readobj -elf-output-style=GNU %t -t | FileCheck %s --check-prefix=SYM
> +
> +# It would be much easier to understand/read this test if llvm-objdump would print
> +# the immediates in hex.
> +# IMM = hex(65540) = 0x10004
> +# PC = 0x10000
> +# As the relocation is PC-relative, IMM + PC = 0x20004 which is the VA of the
> +# correct symbol.
> +
> +# DISASM: Disassembly of section .text:
> +# DISASM-NEXT: $x.0:
> +# DISASM-NEXT:   10000:       28 00 08 58     ldr     x8, #65540
> +
> +# SYM: Symbol table '.symtab'
> +# SYM:  0000000000020004     0 NOTYPE  LOCAL  DEFAULT    5 patatino
> +
> +  ldr x8, patatino
> +  .data
> +  .zero 4
> +patatino:
> Index: test/ELF/aarch64-undefined-weak.s
> ===================================================================
> --- test/ELF/aarch64-undefined-weak.s
> +++ test/ELF/aarch64-undefined-weak.s
> @@ -30,6 +30,8 @@
>   .xword target - .
>  // R_AARCH64_PREL16
>   .hword target - .
> +// R_AARCH64_LD_PREL_LO19
> + ldr x8, target
>  
>  // CHECK: Disassembly of section .text:
>  // 131076 = 0x20004
> @@ -43,3 +45,5 @@
>  // CHECK-NEXT:    2001c: {{.*}} .word   0x00000000
>  // CHECK-NEXT:    20020: {{.*}} .word   0x00000000
>  // CHECK-NEXT:    20024: {{.*}} .short  0x0000
> +// CHECK:         $x.2:
> +// CHECK-NEXT:    20026: {{.*}} ldr     x8, #0
> Index: ELF/InputSection.cpp
> ===================================================================
> --- ELF/InputSection.cpp
> +++ ELF/InputSection.cpp
> @@ -471,6 +471,7 @@
>    case R_AARCH64_PREL32:
>    case R_AARCH64_PREL64:
>    case R_AARCH64_ADR_PREL_LO21:
> +  case R_AARCH64_LD_PREL_LO19:
>      return P + A;
>    }
>    llvm_unreachable("AArch64 pc-relative relocation expected\n");
> Index: ELF/Arch/AArch64.cpp
> ===================================================================
> --- ELF/Arch/AArch64.cpp
> +++ ELF/Arch/AArch64.cpp
> @@ -92,6 +92,7 @@
>    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:
>      return R_PAGE_PC;
> @@ -247,6 +248,7 @@
>      or32le(Loc, (Val & 0x0FFFFFFC) >> 2);
>      break;
>    case R_AARCH64_CONDBR19:
> +  case R_AARCH64_LD_PREL_LO19:
>      checkInt<21>(Loc, Val, Type);
>      or32le(Loc, (Val & 0x1FFFFC) << 3);
>      break;