PowerPC .gnu.attributes

This patch extends Tag_GNU_Power_ABI_FP to cover long double ABIs,
makes the assembler warn about undefined tag values, and removes
similar warnings from the linker.  I think it is better to not
warn in the linker about undefined tag values as future extensions to
the tags then won't result in likely bogus warnings.  This is
consistent with the fact that an older linker won't warn on an
entirely new tag.

include/
	* elf/ppc.h (Tag_GNU_Power_ABI_FP): Comment.
bfd/
	* elf-bfd.h (_bfd_elf_ppc_merge_fp_attributes): Declare.
	* elf32-ppc.c (_bfd_elf_ppc_merge_fp_attributes): New function.
	(ppc_elf_merge_obj_attributes): Use it.  Don't copy first file
	attributes, merge them.  Don't warn about undefined tag bits,
	or copy unknown values to output.
	* elf64-ppc.c (ppc64_elf_merge_private_bfd_data): Call
	_bfd_elf_ppc_merge_fp_attributes.
binutils/
	* readelf.c (display_power_gnu_attribute): Catch truncated section
	for all powerpc attributes.  Display long double ABI.  Don't
	capitalize words, except for names.  Show known bits of tag values
	when some unknown bits are present.  Whitespace fixes.
gas/
	* config/tc-ppc.c (ppc_elf_gnu_attribute): New function.
	(md_pseudo_table <ELF>): Handle "gnu_attribute".
ld/
	* testsuite/ld-powerpc/attr-gnu-4-4.s: Delete.
	* testsuite/ld-powerpc/attr-gnu-4-14.d: Delete.
	* testsuite/ld-powerpc/attr-gnu-4-24.d: Delete.
	* testsuite/ld-powerpc/attr-gnu-4-34.d: Delete.
	* testsuite/ld-powerpc/attr-gnu-4-41.d: Delete.
	* testsuite/ld-powerpc/attr-gnu-4-32.d: Adjust expected warning.
	* testsuite/ld-powerpc/attr-gnu-8-23.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-01.d: Adjust expected output.
	* testsuite/ld-powerpc/attr-gnu-4-02.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-03.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-10.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-11.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-20.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-22.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-4-33.d: Likewise.
	* testsuite/ld-powerpc/attr-gnu-8-11.d: Likewise.
	* testsuite/ld-powerpc/powerpc.exp: Don't run deleted tests.

4 files changed, 110 insertions, 90 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 4e1d209..da0d7a0 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,13 @@
+2016-09-26  Alan Modra  <amodra@gmail.com>
+
+	* elf-bfd.h (_bfd_elf_ppc_merge_fp_attributes): Declare.
+	* elf32-ppc.c (_bfd_elf_ppc_merge_fp_attributes): New function.
+	(ppc_elf_merge_obj_attributes): Use it.  Don't copy first file
+	attributes, merge them.  Don't warn about undefined tag bits,
+	or copy unknown values to output.
+	* elf64-ppc.c (ppc64_elf_merge_private_bfd_data): Call
+	_bfd_elf_ppc_merge_fp_attributes.
+
 2016-09-23  Akihiko Odaki  <akihiko.odaki.4i@stu.hosei.ac.jp>
 
 	PR ld/20595
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index c58bd4f..ed2137e 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -2393,6 +2393,8 @@ extern unsigned int _bfd_elf_ppc_at_tprel_transform
   (unsigned int, unsigned int);
 /* PowerPC elf_object_p tweak.  */
 extern bfd_boolean _bfd_elf_ppc_set_arch (bfd *);
+/* PowerPC .gnu.attributes handling common to both 32-bit and 64-bit.  */
+extern void _bfd_elf_ppc_merge_fp_attributes (bfd *, bfd *);
 
 /* Exported interface for writing elf corefile notes. */
 extern char *elfcore_write_note
diff --git a/bfd/elf32-ppc.c b/bfd/elf32-ppc.c
index e808cb5..dd56a95 100644
--- a/bfd/elf32-ppc.c
+++ b/bfd/elf32-ppc.c
@@ -4653,68 +4653,87 @@ ppc_elf_check_relocs (bfd *abfd,
   return TRUE;
 }
 
-
-/* Merge object attributes from IBFD into OBFD.  Raise an error if
-   there are conflicting attributes.  */
-static bfd_boolean
-ppc_elf_merge_obj_attributes (bfd *ibfd, bfd *obfd)
+/* Warn for conflicting Tag_GNU_Power_ABI_FP attributes between IBFD
+   and OBFD, and merge non-conflicting ones.  */
+void
+_bfd_elf_ppc_merge_fp_attributes (bfd *ibfd, bfd *obfd)
 {
   obj_attribute *in_attr, *in_attrs;
   obj_attribute *out_attr, *out_attrs;
 
-  if (!elf_known_obj_attributes_proc (obfd)[0].i)
-    {
-      /* This is the first object.  Copy the attributes.  */
-      _bfd_elf_copy_obj_attributes (ibfd, obfd);
-
-      /* Use the Tag_null value to indicate the attributes have been
-	 initialized.  */
-      elf_known_obj_attributes_proc (obfd)[0].i = 1;
-
-      return TRUE;
-    }
-
   in_attrs = elf_known_obj_attributes (ibfd)[OBJ_ATTR_GNU];
   out_attrs = elf_known_obj_attributes (obfd)[OBJ_ATTR_GNU];
 
-  /* Check for conflicting Tag_GNU_Power_ABI_FP attributes and merge
-     non-conflicting ones.  */
   in_attr = &in_attrs[Tag_GNU_Power_ABI_FP];
   out_attr = &out_attrs[Tag_GNU_Power_ABI_FP];
+
   if (in_attr->i != out_attr->i)
     {
-      out_attr->type = 1;
-      if (out_attr->i == 0)
-	out_attr->i = in_attr->i;
-      else if (in_attr->i == 0)
+      int in_fp = in_attr->i & 3;
+      int out_fp = out_attr->i & 3;
+
+      if (in_fp == 0)
 	;
-      else if (out_attr->i == 1 && in_attr->i == 2)
+      else if (out_fp == 0)
+	{
+	  out_attr->type = 1;
+	  out_attr->i ^= in_fp;
+	}
+      else if (out_fp != 2 && in_fp == 2)
 	_bfd_error_handler
 	  (_("Warning: %B uses hard float, %B uses soft float"), obfd, ibfd);
-      else if (out_attr->i == 1 && in_attr->i == 3)
+      else if (out_fp == 2 && in_fp != 2)
 	_bfd_error_handler
-	  (_("Warning: %B uses double-precision hard float, %B uses single-precision hard float"),
-	  obfd, ibfd);
-      else if (out_attr->i == 3 && in_attr->i == 1)
+	  (_("Warning: %B uses hard float, %B uses soft float"), ibfd, obfd);
+      else if (out_fp == 1 && in_fp == 3)
 	_bfd_error_handler
-	  (_("Warning: %B uses double-precision hard float, %B uses single-precision hard float"),
-	  ibfd, obfd);
-      else if (out_attr->i == 3 && in_attr->i == 2)
+	  (_("Warning: %B uses double-precision hard float, "
+	     "%B uses single-precision hard float"), obfd, ibfd);
+      else if (out_fp == 3 && in_fp == 1)
 	_bfd_error_handler
-	  (_("Warning: %B uses soft float, %B uses single-precision hard float"),
-	  ibfd, obfd);
-      else if (out_attr->i == 2 && (in_attr->i == 1 || in_attr->i == 3))
+	  (_("Warning: %B uses double-precision hard float, "
+	     "%B uses single-precision hard float"), ibfd, obfd);
+
+      in_fp = in_attr->i & 0xc;
+      out_fp = out_attr->i & 0xc;
+      if (in_fp == 0)
+	;
+      else if (out_fp == 0)
+	{
+	  out_attr->type = 1;
+	  out_attr->i ^= in_fp;
+	}
+      else if (out_fp != 2 * 4 && in_fp == 2 * 4)
 	_bfd_error_handler
-	  (_("Warning: %B uses hard float, %B uses soft float"), ibfd, obfd);
-      else if (in_attr->i > 3)
+	  (_("Warning: %B uses 64-bit long double, "
+	     "%B uses 128-bit long double"), ibfd, obfd);
+      else if (in_fp != 2 * 4 && out_fp == 2 * 4)
 	_bfd_error_handler
-	  (_("Warning: %B uses unknown floating point ABI %d"), ibfd,
-	   in_attr->i);
-      else
+	  (_("Warning: %B uses 64-bit long double, "
+	     "%B uses 128-bit long double"), obfd, ibfd);
+      else if (out_fp == 1 * 4 && in_fp == 3 * 4)
+	_bfd_error_handler
+	  (_("Warning: %B uses IBM long double, "
+	     "%B uses IEEE long double"), ibfd, obfd);
+      else if (out_fp == 3 * 4 && in_fp == 1 * 4)
 	_bfd_error_handler
-	  (_("Warning: %B uses unknown floating point ABI %d"), obfd,
-	   out_attr->i);
+	  (_("Warning: %B uses IBM long double, "
+	     "%B uses IEEE long double"), obfd, ibfd);
     }
+}
+
+/* Merge object attributes from IBFD into OBFD.  Warn if
+   there are conflicting attributes.  */
+static bfd_boolean
+ppc_elf_merge_obj_attributes (bfd *ibfd, bfd *obfd)
+{
+  obj_attribute *in_attr, *in_attrs;
+  obj_attribute *out_attr, *out_attrs;
+
+  _bfd_elf_ppc_merge_fp_attributes (ibfd, obfd);
+
+  in_attrs = elf_known_obj_attributes (ibfd)[OBJ_ATTR_GNU];
+  out_attrs = elf_known_obj_attributes (obfd)[OBJ_ATTR_GNU];
 
   /* Check for conflicting Tag_GNU_Power_ABI_Vector attributes and
      merge non-conflicting ones.  */
@@ -4722,48 +4741,36 @@ ppc_elf_merge_obj_attributes (bfd *ibfd, bfd *obfd)
   out_attr = &out_attrs[Tag_GNU_Power_ABI_Vector];
   if (in_attr->i != out_attr->i)
     {
-      const char *in_abi = NULL, *out_abi = NULL;
-
-      switch (in_attr->i)
-	{
-	case 1: in_abi = "generic"; break;
-	case 2: in_abi = "AltiVec"; break;
-	case 3: in_abi = "SPE"; break;
-	}
+      int in_vec = in_attr->i & 3;
+      int out_vec = out_attr->i & 3;
 
-      switch (out_attr->i)
+      if (in_vec == 0)
+	;
+      else if (out_vec == 0)
 	{
-	case 1: out_abi = "generic"; break;
-	case 2: out_abi = "AltiVec"; break;
-	case 3: out_abi = "SPE"; break;
+	  out_attr->type = 1;
+	  out_attr->i = in_vec;
 	}
-
-      out_attr->type = 1;
-      if (out_attr->i == 0)
-	out_attr->i = in_attr->i;
-      else if (in_attr->i == 0)
-	;
       /* For now, allow generic to transition to AltiVec or SPE
 	 without a warning.  If GCC marked files with their stack
 	 alignment and used don't-care markings for files which are
 	 not affected by the vector ABI, we could warn about this
 	 case too.  */
-      else if (out_attr->i == 1)
-	out_attr->i = in_attr->i;
-      else if (in_attr->i == 1)
+      else if (in_vec == 1)
 	;
-      else if (in_abi == NULL)
-	_bfd_error_handler
-	  (_("Warning: %B uses unknown vector ABI %d"), ibfd,
-	   in_attr->i);
-      else if (out_abi == NULL)
+      else if (out_vec == 1)
+	{
+	  out_attr->type = 1;
+	  out_attr->i = in_vec;
+	}
+      else if (out_vec < in_vec)
 	_bfd_error_handler
-	  (_("Warning: %B uses unknown vector ABI %d"), obfd,
-	   in_attr->i);
-      else
+	  (_("Warning: %B uses AltiVec vector ABI, %B uses SPE vector ABI"),
+	   obfd, ibfd);
+      else if (out_vec > in_vec)
 	_bfd_error_handler
-	  (_("Warning: %B uses vector ABI \"%s\", %B uses \"%s\""),
-	   ibfd, obfd, in_abi, out_abi);
+	  (_("Warning: %B uses AltiVec vector ABI, %B uses SPE vector ABI"),
+	   ibfd, obfd);
     }
 
   /* Check for conflicting Tag_GNU_Power_ABI_Struct_Return attributes
@@ -4772,25 +4779,24 @@ ppc_elf_merge_obj_attributes (bfd *ibfd, bfd *obfd)
   out_attr = &out_attrs[Tag_GNU_Power_ABI_Struct_Return];
   if (in_attr->i != out_attr->i)
     {
-      out_attr->type = 1;
-      if (out_attr->i == 0)
-       out_attr->i = in_attr->i;
-      else if (in_attr->i == 0)
+      int in_struct = in_attr->i & 3;
+      int out_struct = out_attr->i & 3;
+
+      if (in_struct == 0 || in_struct == 3)
        ;
-      else if (out_attr->i == 1 && in_attr->i == 2)
-       _bfd_error_handler
-         (_("Warning: %B uses r3/r4 for small structure returns, %B uses memory"), obfd, ibfd);
-      else if (out_attr->i == 2 && in_attr->i == 1)
-       _bfd_error_handler
-         (_("Warning: %B uses r3/r4 for small structure returns, %B uses memory"), ibfd, obfd);
-      else if (in_attr->i > 2)
-       _bfd_error_handler
-         (_("Warning: %B uses unknown small structure return convention %d"), ibfd,
-          in_attr->i);
-      else
-       _bfd_error_handler
-         (_("Warning: %B uses unknown small structure return convention %d"), obfd,
-          out_attr->i);
+      else if (out_struct == 0)
+	{
+	  out_attr->type = 1;
+	  out_attr->i = in_struct;
+	}
+      else if (out_struct < in_struct)
+	_bfd_error_handler
+	  (_("Warning: %B uses r3/r4 for small structure returns, "
+	     "%B uses memory"), obfd, ibfd);
+      else if (out_struct > in_struct)
+	_bfd_error_handler
+	  (_("Warning: %B uses r3/r4 for small structure returns, "
+	     "%B uses memory"), ibfd, obfd);
     }
 
   /* Merge Tag_compatibility attributes and any common GNU ones.  */
diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index eeb68e5..d6acc1f3 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -6030,6 +6030,8 @@ ppc64_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
       return FALSE;
     }
 
+  _bfd_elf_ppc_merge_fp_attributes (ibfd, obfd);
+
   /* Merge Tag_compatibility attributes and any common GNU ones.  */
   _bfd_elf_merge_object_attributes (ibfd, obfd);