[ELF] --icf: don't fold a section without relocation and a section with relocations for SHT_REL

Fix llvm#57693

Author: MaskRay

lld/ELF/ICF.cpp

@@ -323,8 +323,9 @@ bool ICF<ELFT>::equalsConstant(const InputSection *a, const InputSection *b) {
 
   const RelsOrRelas<ELFT> ra = a->template relsOrRelas<ELFT>();
   const RelsOrRelas<ELFT> rb = b->template relsOrRelas<ELFT>();
-  return ra.areRelocsRel() ? constantEq(a, ra.rels, b, rb.rels)
-                           : constantEq(a, ra.relas, b, rb.relas);
+  return ra.areRelocsRel() || rb.areRelocsRel()
+             ? constantEq(a, ra.rels, b, rb.rels)
+             : constantEq(a, ra.relas, b, rb.relas);
 }
 
 // Compare two lists of relocations. Returns true if all pairs of
@@ -371,8 +372,9 @@ template <class ELFT>
 bool ICF<ELFT>::equalsVariable(const InputSection *a, const InputSection *b) {
   const RelsOrRelas<ELFT> ra = a->template relsOrRelas<ELFT>();
   const RelsOrRelas<ELFT> rb = b->template relsOrRelas<ELFT>();
-  return ra.areRelocsRel() ? variableEq(a, ra.rels, b, rb.rels)
-                           : variableEq(a, ra.relas, b, rb.relas);
+  return ra.areRelocsRel() || rb.areRelocsRel()
+             ? variableEq(a, ra.rels, b, rb.rels)
+             : variableEq(a, ra.relas, b, rb.relas);
 }
 
 template <class ELFT> size_t ICF<ELFT>::findBoundary(size_t begin, size_t end) {

lld/test/ELF/icf10.s

@@ -1,5 +1,7 @@
 # REQUIRES: x86
 
+# RUN: llvm-mc -filetype=obj -triple=i686 %s -o %t.o
+# RUN: ld.lld --icf=all %t.o -o /dev/null --print-icf-sections 2>&1 | FileCheck %s
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-freebsd %s -o %t.o
 # RUN: ld.lld --icf=all %t.o -o /dev/null --print-icf-sections 2>&1 | FileCheck %s
 
@@ -8,10 +10,13 @@
 
 # CHECK-NOT: selected
 
+.section .text.orig,"ax"
+  .quad -1
+
 .section .text.foo,"ax"
   .quad -1
-  .reloc 0, R_X86_64_NONE, 0
+  .reloc 0, BFD_RELOC_NONE, 0
 
 .section .text.bar,"ax"
   .quad -1
-  .reloc 1, R_X86_64_NONE, 0
+  .reloc 1, BFD_RELOC_NONE, 0