[ELF][PPC64] Fix getRelExpr for R_PPC64_REL32

[syzaara]

Summary

The relocation R_PPC64_REL32 should return R_PC for getRelExpr since it computes S + A - P.

[ruiu]

LGTM

lld/ELF/Arch/PPC64.cpp

RelExpr PPC64::getRelExpr(RelType Type, const Symbol &S,
   case R_PPC64_TOC16_LO_DS:
     return R_GOTREL;
   case R_PPC64_TOC:
     return R_PPC_TOC;
   case R_PPC64_REL24:
     return R_PPC_CALL_PLT;
   case R_PPC64_REL16_LO:
   case R_PPC64_REL16_HA:
+  case R_PPC64_REL32:
     return R_PC;
   default:
     return R_ABS;
   }
 }
 
 void PPC64::writeGotHeader(uint8_t *Buf) const {
   write64(Buf, getPPC64TocBase());

lld/test/ELF/ppc64-relocs.s

 # REQUIRES: ppc
 
 # RUN: llvm-mc -filetype=obj -triple=powerpc64le-unknown-linux %s -o %t
 # RUN: ld.lld %t -o %t2
-# RUN: llvm-objdump -d %t2 | FileCheck %s
+# RUN: llvm-objdump -D %t2 | FileCheck %s --check-prefix=rodataLE
+# RUN: llvm-objdump -D %t2 | FileCheck %s
 
 # RUN: llvm-mc -filetype=obj -triple=powerpc64-unknown-linux %s -o %t
 # RUN: ld.lld %t -o %t2
-# RUN: llvm-objdump -d %t2 | FileCheck %s
+# RUN: llvm-objdump -D %t2 | FileCheck %s --check-prefix=rodataBE
+# RUN: llvm-objdump -D %t2 | FileCheck %s
 
 .text
 .global _start
 _start:
 .Lfoo:
   li      0,1
   li      3,42
   sc
 
-.section        ".toc","aw"
+.section        .rodata,"a",@progbits
+        .p2align        2
+.LJTI0_0:
+        .long   .LBB0_2-.LJTI0_0
+
+.section        .toc,"aw",@progbits
 .L1:
 .quad           22, 37, 89, 47
+.LC0:
+        .tc .LJTI0_0[TC],.LJTI0_0
 
 .section .R_PPC64_TOC16_LO_DS,"ax",@progbits
 .globl .FR_PPC64_TOC16_LO_DS
 .FR_PPC64_TOC16_LO_DS:
   ld 1, .L1@toc@l(2)
 
 # CHECK: Disassembly of section .R_PPC64_TOC16_LO_DS:
 # CHECK: .FR_PPC64_TOC16_LO_DS:

 .globl .FR_PPC64_ADDR16_HIGHESTA
 .FR_PPC64_ADDR16_HIGHESTA:
   li 1, .Lfoo@highesta
 
 # CHECK: Disassembly of section .R_PPC64_ADDR16_HIGHESTA:
 # CHECK: .FR_PPC64_ADDR16_HIGHESTA:
 # CHECK: 10010038: {{.*}} li 1, 0
 
+.section  .R_PPC64_REL32, "ax",@progbits
+.globl .FR_PPC64_REL32
+.FR_PPC64_REL32:
+  addis 5, 2, .LC0@toc@ha
+  ld 5, .LC0@toc@l(5)
+.LBB0_2:
+  add 3, 3, 4
+
+# rodataLE: Disassembly of section .rodata:
+# rodataLE: .rodata:
+# rodataLE: 10000190: b4 fe 00 00
+
+# rodataBE: Disassembly of section .rodata:
+# rodataBE: .rodata:
+# rodataBE: 10000190: 00 00 fe b4
+
+# Address of rodata + value stored at rodata entry
+# should equal address of LBB0_2.
+# 0x10000190 + 0xfeb4 = 0x10010044
+# CHECK: Disassembly of section .R_PPC64_REL32:
+# CHECK: .FR_PPC64_REL32:
+# CHECK: 1001003c: {{.*}} addis 5, 2, -1
+# CHECK: 10010040: {{.*}} ld 5, -32736(5)
+# CHECK: 10010044: {{.*}} add 3, 3, 4