[PATCH v3 1/4] microblaze: add BFD_RELOC_8 and BFD_RELOC_16 cases

[Sam Price]

From: Samuel Price <thesamprice@gmail.com>

md_apply_fix has cases for BFD_RELOC_32, BFD_RELOC_64 and for the
MicroBlaze-specific relocations, but none for BFD_RELOC_8 or BFD_RELOC_16.
Those fall through to the default and nothing is written, so a byte or
halfword datum whose value is only known at fixup time assembles to zero.
The fixup is then resolved and turned into BFD_RELOC_NONE, so no relocation
survives for the linker to correct it either, and the zero is permanent.

Write the value with md_number_to_chars, as aarch64, mips and sparc do for
these relocations.  It writes in target byte order, so the two cases need no
endianness test of their own.  The guard is fx_done, which is what actually
means "no relocation will survive, so resolve it here".

Fixes gas/all/simple-forward.  It also fixes gas/all/forward, which was
xfailed for microblaze-*-*, so drop it from that xfail list and update the
comment above it, which still named microblaze.

gas testsuite, whole suite, pristine master:

  microblaze-elf      327 pass, 1 unexpected failure -> 329 pass, 0
  microblazeel-elf    326 pass, 4 unexpected failures -> 328 pass, 2

The xfail glob never covered microblazeel-*, so on that target
gas/all/forward was failing outright rather than xfailing; it passes now.
The two remaining microblazeel failures, "difference of two undefined
symbols" and "all end", are pre-existing and untouched by this patch.

gas/
	* config/tc-microblaze.c (md_apply_fix): Handle BFD_RELOC_8 and
	BFD_RELOC_16.
	* testsuite/gas/all/forward.d: Remove the microblaze-*-* xfail.

Signed-off-by: Sam Price <thesamprice@gmail.com>
Assisted-by: Claude (Anthropic)
---
 gas/config/tc-microblaze.c      | 7 +++++++
 gas/testsuite/gas/all/forward.d | 4 ++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/gas/config/tc-microblaze.c b/gas/config/tc-microblaze.c
index 3e3dca81921..fcc41a7f1f2 100644
--- a/gas/config/tc-microblaze.c
+++ b/gas/config/tc-microblaze.c
@@ -2145,6 +2145,13 @@ md_apply_fix (fixS *   fixP,
 	    }
 	}
       break;
+    case BFD_RELOC_8:
+    case BFD_RELOC_16:
+      /* md_number_to_chars writes in target byte order.  */
+      if (fixP->fx_done)
+	md_number_to_chars (buf, val, fixP->fx_size);
+      break;
+
     case BFD_RELOC_32:
     case BFD_RELOC_RVA:
     case BFD_RELOC_32_PCREL:
diff --git a/gas/testsuite/gas/all/forward.d b/gas/testsuite/gas/all/forward.d
index d921ec517be..39f7b2941e8 100644
--- a/gas/testsuite/gas/all/forward.d
+++ b/gas/testsuite/gas/all/forward.d
@@ -8,10 +8,10 @@
 # choose to emit them even though the relocs are in .data, leading to
 # "redefined symbol cannot be used on reloc".
 #xfail: am33*-*-* crx*-*-* h8300*-*-* mn10200*-*-* mn10300*-*-*
-# mep and microblaze use complex relocs and don't resolve the relocs.
+# mep uses complex relocs and doesn't resolve the relocs.
 # one of the relocs references minus_one, which is a bug, but no one
 # seems bothered enough to fix this.
-#xfail: mep-*-* microblaze-*-*
+#xfail: mep-*-*
 
 .*: .*
 
-- 
2.39.5 (Apple Git-154)