Move x86_64 PE changes out of bfd_perform_relocation

bfd_perform_relocation should not have special case target code.  This
patch moves the code that was there for x86_64 PE linking to ELF
output into the x86_64 PE howto special function, correcting that
function for linking to targets other than ELF too.  The fixes in
bfd_perform_relocation were over-complicated due to needing to
compensate for things that had already gone wrong in coff_amd64_reloc.
In particular, an adjustment for pc-relative relocs was done in a way
that meant adjustment for things related to symbol offsets was lost.
I think those two things are orthogonal, but who knows with COFF where
addends and symbol values are found randomly in the section contents.

Note that linking natively to an x86_64 PE output relocates by
coff_pe_amd64_relocate_section, which does not use arelent relocs or
bfd_perform_relocation, but be aware of coff_amd64_rtype_to_howto
hacking addends for relocations.  The adjustments for a particular
relocation type there and in coff_amd64_reloc ought to match after
taking into consideration CALC_ADDEND.  They don't.  For example,
the pc-relative adjustment for R_PCRWORD is 2 bytes in
coff_amd64_reloc and 4 bytes in coff_amd64_rtype_to_howto.

	* reloc.c (bfd_perform_relocation): Revert 2021-01-12 and
	2020-09-16 changes.
	* coff-x86_64.c (coff_amd64_reloc): Do more or less the same
	adjustments here instead.  Separate pc-relative adjustments
	from symbol related adjustments.  Tidy comments and formatting.

1 files changed, 1 insertions, 25 deletions

diff --git a/bfd/reloc.c b/bfd/reloc.c
index a7547187ebe..5ed7bb8e596 100644
--- a/bfd/reloc.c
+++ b/bfd/reloc.c
@@ -51,7 +51,7 @@ SECTION
 #include "bfdlink.h"
 #include "libbfd.h"
 #include "bfdver.h"
-#include "coff/x86_64.h"
+
 /*
 DOCDD
 INODE
@@ -905,30 +905,6 @@ space consuming.  For each target:
 	    }
 	}
     }
-  else if (abfd->xvec->flavour == bfd_target_coff_flavour
-	   && (input_section->output_section->owner->xvec->flavour
-	       == bfd_target_elf_flavour)
-	   && strcmp (abfd->xvec->name, "pe-x86-64") == 0
-	   && strcmp (input_section->output_section->owner->xvec->name,
-		      "elf64-x86-64") == 0)
-    {
-      /* NB: bfd_perform_relocation isn't called to generate PE binary.
-	 _bfd_relocate_contents is called instead.  When linking PE
-	 object files to generate ELF output, _bfd_relocate_contents
-	 isn't called and bfd_perform_relocation is used.  We need to
-	 adjust relocation here.  */
-      relocation -= reloc_entry->addend;
-      if (howto->type >= R_AMD64_PCRLONG_1
-	  && howto->type <= R_AMD64_PCRLONG_5)
-	relocation -= (bfd_vma)(howto->type - R_AMD64_PCRLONG);
-      else if (howto->type == R_AMD64_DIR64
-	       || howto->type == R_AMD64_DIR32)
-	{
-	  bfd_vma val = read_reloc (abfd, (bfd_byte *) data + octets,
-				    howto);
-	  relocation -= val & howto->src_mask;
-	}
-    }
 
   /* FIXME: This overflow checking is incomplete, because the value
      might have overflowed before we get here.  For a correct check we