Add support for secidx relocations to aarch64-w64-mingw32

This patch adds support for the .secidx directive and its corresponding
relocation to aarch64-w64-mingw32. As with x86, this is a two-byte LE
integer which gets filled in with the 1-based index of the output
section that a symbol ends up in.

This is needed for PDBs, which represent addresses as a .secrel32,
.secidx pair.

The test is substantially the same as for amd64, but with changes made
for padding and alignment.

1 files changed, 35 insertions, 1 deletions

diff --git a/bfd/coff-aarch64.c b/bfd/coff-aarch64.c
index 73fa2442dfe..12e242e18d0 100644
--- a/bfd/coff-aarch64.c
+++ b/bfd/coff-aarch64.c
@@ -305,6 +305,10 @@ static const reloc_howto_type arm64_reloc_howto_secrel
 = HOW (IMAGE_REL_ARM64_SECREL,
        0, 4, 32, false, 0, dont, secrel_reloc, 0xffffffff);
 
+static const reloc_howto_type arm64_reloc_howto_secidx
+= HOW (IMAGE_REL_ARM64_SECTION,
+       0, 2, 16, false, 0, dont, NULL, 0xffff);
+
 static const reloc_howto_type* const arm64_howto_table[] = {
      &arm64_reloc_howto_abs,
      &arm64_reloc_howto_64,
@@ -318,7 +322,8 @@ static const reloc_howto_type* const arm64_howto_table[] = {
      &arm64_reloc_howto_branch14,
      &arm64_reloc_howto_pgoff12a,
      &arm64_reloc_howto_32nb,
-     &arm64_reloc_howto_secrel
+     &arm64_reloc_howto_secrel,
+     &arm64_reloc_howto_secidx
 };
 
 /* No adjustment to addends should be needed.  The actual relocation
@@ -372,6 +377,8 @@ coff_aarch64_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED, bfd_reloc_code_real
     return &arm64_reloc_howto_32nb;
   case BFD_RELOC_32_SECREL:
     return &arm64_reloc_howto_secrel;
+  case BFD_RELOC_16_SECIDX:
+    return &arm64_reloc_howto_secidx;
   default:
     BFD_FAIL ();
     return NULL;
@@ -428,6 +435,8 @@ coff_aarch64_rtype_lookup (unsigned int code)
       return &arm64_reloc_howto_32nb;
     case IMAGE_REL_ARM64_SECREL:
       return &arm64_reloc_howto_secrel;
+    case IMAGE_REL_ARM64_SECTION:
+      return &arm64_reloc_howto_secidx;
     default:
       return NULL;
   }
@@ -847,6 +856,31 @@ coff_pe_aarch64_relocate_section (bfd *output_bfd,
 	    break;
 	  }
 
+	case IMAGE_REL_ARM64_SECTION:
+	  {
+	    uint16_t idx = 0, i = 1;
+	    asection *s;
+
+	    s = output_bfd->sections;
+	    while (s)
+	      {
+		if (s == sec->output_section)
+		  {
+		    idx = i;
+		    break;
+		  }
+
+		i++;
+		s = s->next;
+	      }
+
+
+	    bfd_putl16 (idx, contents + rel->r_vaddr);
+	    rel->r_type = IMAGE_REL_ARM64_ABSOLUTE;
+
+	    break;
+	  }
+
 	default:
 	  info->callbacks->einfo (_("%F%P: Unhandled relocation type %u\n"),
 				  rel->r_type);