MIPS/BFD: Factor out ELF file header flag checks

Factor out the parts of `_bfd_mips_elf_merge_private_bfd_data'
responsible for ELF file header flag compatibility checks to
`mips_elf_merge_obj_e_flags'.  As a side effect remove a premature
return point from `_bfd_mips_elf_merge_private_bfd_data'.  No functional
change otherwise.

	bfd/
	* elfxx-mips.c (mips_elf_merge_obj_e_flags): New function,
	factored out from...
	(_bfd_mips_elf_merge_private_bfd_data): ... here.

2 files changed, 200 insertions, 182 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index cd9e1b1..cea5647 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,11 @@
 2016-01-04  Maciej W. Rozycki  <macro@imgtec.com>
 
+	* elfxx-mips.c (mips_elf_merge_obj_e_flags): New function,
+	factored out from...
+	(_bfd_mips_elf_merge_private_bfd_data): ... here.
+
+2016-01-04  Maciej W. Rozycki  <macro@imgtec.com>
+
 	* elfxx-mips.c (_bfd_mips_elf_merge_private_bfd_data): Fold the
 	handling of input MIPS ABI flags together.
 
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c
index 89d4409..f71be49 100644
--- a/bfd/elfxx-mips.c
+++ b/bfd/elfxx-mips.c
@@ -14867,6 +14867,199 @@ _bfd_mips_elf_final_link (bfd *abfd, struct bfd_link_info *info)
   return TRUE;
 }
 
+/* Merge object file header flags from IBFD into OBFD.  Raise an error
+   if there are conflicting settings.  */
+
+static bfd_boolean
+mips_elf_merge_obj_e_flags (bfd *ibfd, bfd *obfd)
+{
+  struct mips_elf_obj_tdata *out_tdata = mips_elf_tdata (obfd);
+  flagword old_flags;
+  flagword new_flags;
+  bfd_boolean ok;
+
+  new_flags = elf_elfheader (ibfd)->e_flags;
+  elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_NOREORDER;
+  old_flags = elf_elfheader (obfd)->e_flags;
+
+  /* Check flag compatibility.  */
+
+  new_flags &= ~EF_MIPS_NOREORDER;
+  old_flags &= ~EF_MIPS_NOREORDER;
+
+  /* Some IRIX 6 BSD-compatibility objects have this bit set.  It
+     doesn't seem to matter.  */
+  new_flags &= ~EF_MIPS_XGOT;
+  old_flags &= ~EF_MIPS_XGOT;
+
+  /* MIPSpro generates ucode info in n64 objects.  Again, we should
+     just be able to ignore this.  */
+  new_flags &= ~EF_MIPS_UCODE;
+  old_flags &= ~EF_MIPS_UCODE;
+
+  /* DSOs should only be linked with CPIC code.  */
+  if ((ibfd->flags & DYNAMIC) != 0)
+    new_flags |= EF_MIPS_PIC | EF_MIPS_CPIC;
+
+  if (new_flags == old_flags)
+    return TRUE;
+
+  ok = TRUE;
+
+  if (((new_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0)
+      != ((old_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0))
+    {
+      (*_bfd_error_handler)
+	(_("%B: warning: linking abicalls files with non-abicalls files"),
+	 ibfd);
+      ok = TRUE;
+    }
+
+  if (new_flags & (EF_MIPS_PIC | EF_MIPS_CPIC))
+    elf_elfheader (obfd)->e_flags |= EF_MIPS_CPIC;
+  if (! (new_flags & EF_MIPS_PIC))
+    elf_elfheader (obfd)->e_flags &= ~EF_MIPS_PIC;
+
+  new_flags &= ~ (EF_MIPS_PIC | EF_MIPS_CPIC);
+  old_flags &= ~ (EF_MIPS_PIC | EF_MIPS_CPIC);
+
+  /* Compare the ISAs.  */
+  if (mips_32bit_flags_p (old_flags) != mips_32bit_flags_p (new_flags))
+    {
+      (*_bfd_error_handler)
+	(_("%B: linking 32-bit code with 64-bit code"),
+	 ibfd);
+      ok = FALSE;
+    }
+  else if (!mips_mach_extends_p (bfd_get_mach (ibfd), bfd_get_mach (obfd)))
+    {
+      /* OBFD's ISA isn't the same as, or an extension of, IBFD's.  */
+      if (mips_mach_extends_p (bfd_get_mach (obfd), bfd_get_mach (ibfd)))
+	{
+	  /* Copy the architecture info from IBFD to OBFD.  Also copy
+	     the 32-bit flag (if set) so that we continue to recognise
+	     OBFD as a 32-bit binary.  */
+	  bfd_set_arch_info (obfd, bfd_get_arch_info (ibfd));
+	  elf_elfheader (obfd)->e_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH);
+	  elf_elfheader (obfd)->e_flags
+	    |= new_flags & (EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
+
+	  /* Update the ABI flags isa_level, isa_rev, isa_ext fields.  */
+	  update_mips_abiflags_isa (obfd, &out_tdata->abiflags);
+
+	  /* Copy across the ABI flags if OBFD doesn't use them
+	     and if that was what caused us to treat IBFD as 32-bit.  */
+	  if ((old_flags & EF_MIPS_ABI) == 0
+	      && mips_32bit_flags_p (new_flags)
+	      && !mips_32bit_flags_p (new_flags & ~EF_MIPS_ABI))
+	    elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_ABI;
+	}
+      else
+	{
+	  /* The ISAs aren't compatible.  */
+	  (*_bfd_error_handler)
+	    (_("%B: linking %s module with previous %s modules"),
+	     ibfd,
+	     bfd_printable_name (ibfd),
+	     bfd_printable_name (obfd));
+	  ok = FALSE;
+	}
+    }
+
+  new_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
+  old_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
+
+  /* Compare ABIs.  The 64-bit ABI does not use EF_MIPS_ABI.  But, it
+     does set EI_CLASS differently from any 32-bit ABI.  */
+  if ((new_flags & EF_MIPS_ABI) != (old_flags & EF_MIPS_ABI)
+      || (elf_elfheader (ibfd)->e_ident[EI_CLASS]
+	  != elf_elfheader (obfd)->e_ident[EI_CLASS]))
+    {
+      /* Only error if both are set (to different values).  */
+      if (((new_flags & EF_MIPS_ABI) && (old_flags & EF_MIPS_ABI))
+	  || (elf_elfheader (ibfd)->e_ident[EI_CLASS]
+	      != elf_elfheader (obfd)->e_ident[EI_CLASS]))
+	{
+	  (*_bfd_error_handler)
+	    (_("%B: ABI mismatch: linking %s module with previous %s modules"),
+	     ibfd,
+	     elf_mips_abi_name (ibfd),
+	     elf_mips_abi_name (obfd));
+	  ok = FALSE;
+	}
+      new_flags &= ~EF_MIPS_ABI;
+      old_flags &= ~EF_MIPS_ABI;
+    }
+
+  /* Compare ASEs.  Forbid linking MIPS16 and microMIPS ASE modules together
+     and allow arbitrary mixing of the remaining ASEs (retain the union).  */
+  if ((new_flags & EF_MIPS_ARCH_ASE) != (old_flags & EF_MIPS_ARCH_ASE))
+    {
+      int old_micro = old_flags & EF_MIPS_ARCH_ASE_MICROMIPS;
+      int new_micro = new_flags & EF_MIPS_ARCH_ASE_MICROMIPS;
+      int old_m16 = old_flags & EF_MIPS_ARCH_ASE_M16;
+      int new_m16 = new_flags & EF_MIPS_ARCH_ASE_M16;
+      int micro_mis = old_m16 && new_micro;
+      int m16_mis = old_micro && new_m16;
+
+      if (m16_mis || micro_mis)
+	{
+	  (*_bfd_error_handler)
+	    (_("%B: ASE mismatch: linking %s module with previous %s modules"),
+	     ibfd,
+	     m16_mis ? "MIPS16" : "microMIPS",
+	     m16_mis ? "microMIPS" : "MIPS16");
+	  ok = FALSE;
+	}
+
+      elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_ARCH_ASE;
+
+      new_flags &= ~ EF_MIPS_ARCH_ASE;
+      old_flags &= ~ EF_MIPS_ARCH_ASE;
+    }
+
+  /* Compare NaN encodings.  */
+  if ((new_flags & EF_MIPS_NAN2008) != (old_flags & EF_MIPS_NAN2008))
+    {
+      _bfd_error_handler (_("%B: linking %s module with previous %s modules"),
+			  ibfd,
+			  (new_flags & EF_MIPS_NAN2008
+			   ? "-mnan=2008" : "-mnan=legacy"),
+			  (old_flags & EF_MIPS_NAN2008
+			   ? "-mnan=2008" : "-mnan=legacy"));
+      ok = FALSE;
+      new_flags &= ~EF_MIPS_NAN2008;
+      old_flags &= ~EF_MIPS_NAN2008;
+    }
+
+  /* Compare FP64 state.  */
+  if ((new_flags & EF_MIPS_FP64) != (old_flags & EF_MIPS_FP64))
+    {
+      _bfd_error_handler (_("%B: linking %s module with previous %s modules"),
+			  ibfd,
+			  (new_flags & EF_MIPS_FP64
+			   ? "-mfp64" : "-mfp32"),
+			  (old_flags & EF_MIPS_FP64
+			   ? "-mfp64" : "-mfp32"));
+      ok = FALSE;
+      new_flags &= ~EF_MIPS_FP64;
+      old_flags &= ~EF_MIPS_FP64;
+    }
+
+  /* Warn about any other mismatches */
+  if (new_flags != old_flags)
+    {
+      (*_bfd_error_handler)
+	(_("%B: uses different e_flags (0x%lx) fields than previous modules "
+	   "(0x%lx)"),
+	 ibfd, (unsigned long) new_flags,
+	 (unsigned long) old_flags);
+      ok = FALSE;
+    }
+
+  return ok;
+}
+
 /* Merge object attributes from IBFD into OBFD.  Raise an error if
    there are conflicting attributes.  */
 static bfd_boolean
@@ -15026,9 +15219,6 @@ _bfd_mips_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
 {
   struct mips_elf_obj_tdata *out_tdata;
   struct mips_elf_obj_tdata *in_tdata;
-  flagword old_flags;
-  flagword new_flags;
-  bfd_boolean ok;
   bfd_boolean null_input_bfd = TRUE;
   asection *sec;
   obj_attribute *out_attr;
@@ -15186,185 +15376,7 @@ _bfd_mips_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
   out_tdata->abiflags.ases |= in_tdata->abiflags.ases;
   out_tdata->abiflags.flags1 |= in_tdata->abiflags.flags1;
 
-  new_flags = elf_elfheader (ibfd)->e_flags;
-  elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_NOREORDER;
-  old_flags = elf_elfheader (obfd)->e_flags;
-
-  /* Check flag compatibility.  */
-
-  new_flags &= ~EF_MIPS_NOREORDER;
-  old_flags &= ~EF_MIPS_NOREORDER;
-
-  /* Some IRIX 6 BSD-compatibility objects have this bit set.  It
-     doesn't seem to matter.  */
-  new_flags &= ~EF_MIPS_XGOT;
-  old_flags &= ~EF_MIPS_XGOT;
-
-  /* MIPSpro generates ucode info in n64 objects.  Again, we should
-     just be able to ignore this.  */
-  new_flags &= ~EF_MIPS_UCODE;
-  old_flags &= ~EF_MIPS_UCODE;
-
-  /* DSOs should only be linked with CPIC code.  */
-  if ((ibfd->flags & DYNAMIC) != 0)
-    new_flags |= EF_MIPS_PIC | EF_MIPS_CPIC;
-
-  if (new_flags == old_flags)
-    return TRUE;
-
-  ok = TRUE;
-
-  if (((new_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0)
-      != ((old_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0))
-    {
-      (*_bfd_error_handler)
-	(_("%B: warning: linking abicalls files with non-abicalls files"),
-	 ibfd);
-      ok = TRUE;
-    }
-
-  if (new_flags & (EF_MIPS_PIC | EF_MIPS_CPIC))
-    elf_elfheader (obfd)->e_flags |= EF_MIPS_CPIC;
-  if (! (new_flags & EF_MIPS_PIC))
-    elf_elfheader (obfd)->e_flags &= ~EF_MIPS_PIC;
-
-  new_flags &= ~ (EF_MIPS_PIC | EF_MIPS_CPIC);
-  old_flags &= ~ (EF_MIPS_PIC | EF_MIPS_CPIC);
-
-  /* Compare the ISAs.  */
-  if (mips_32bit_flags_p (old_flags) != mips_32bit_flags_p (new_flags))
-    {
-      (*_bfd_error_handler)
-	(_("%B: linking 32-bit code with 64-bit code"),
-	 ibfd);
-      ok = FALSE;
-    }
-  else if (!mips_mach_extends_p (bfd_get_mach (ibfd), bfd_get_mach (obfd)))
-    {
-      /* OBFD's ISA isn't the same as, or an extension of, IBFD's.  */
-      if (mips_mach_extends_p (bfd_get_mach (obfd), bfd_get_mach (ibfd)))
-	{
-	  /* Copy the architecture info from IBFD to OBFD.  Also copy
-	     the 32-bit flag (if set) so that we continue to recognise
-	     OBFD as a 32-bit binary.  */
-	  bfd_set_arch_info (obfd, bfd_get_arch_info (ibfd));
-	  elf_elfheader (obfd)->e_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH);
-	  elf_elfheader (obfd)->e_flags
-	    |= new_flags & (EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
-
-	  /* Update the ABI flags isa_level, isa_rev, isa_ext fields.  */
-	  update_mips_abiflags_isa (obfd, &out_tdata->abiflags);
-
-	  /* Copy across the ABI flags if OBFD doesn't use them
-	     and if that was what caused us to treat IBFD as 32-bit.  */
-	  if ((old_flags & EF_MIPS_ABI) == 0
-	      && mips_32bit_flags_p (new_flags)
-	      && !mips_32bit_flags_p (new_flags & ~EF_MIPS_ABI))
-	    elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_ABI;
-	}
-      else
-	{
-	  /* The ISAs aren't compatible.  */
-	  (*_bfd_error_handler)
-	    (_("%B: linking %s module with previous %s modules"),
-	     ibfd,
-	     bfd_printable_name (ibfd),
-	     bfd_printable_name (obfd));
-	  ok = FALSE;
-	}
-    }
-
-  new_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
-  old_flags &= ~(EF_MIPS_ARCH | EF_MIPS_MACH | EF_MIPS_32BITMODE);
-
-  /* Compare ABIs.  The 64-bit ABI does not use EF_MIPS_ABI.  But, it
-     does set EI_CLASS differently from any 32-bit ABI.  */
-  if ((new_flags & EF_MIPS_ABI) != (old_flags & EF_MIPS_ABI)
-      || (elf_elfheader (ibfd)->e_ident[EI_CLASS]
-	  != elf_elfheader (obfd)->e_ident[EI_CLASS]))
-    {
-      /* Only error if both are set (to different values).  */
-      if (((new_flags & EF_MIPS_ABI) && (old_flags & EF_MIPS_ABI))
-	  || (elf_elfheader (ibfd)->e_ident[EI_CLASS]
-	      != elf_elfheader (obfd)->e_ident[EI_CLASS]))
-	{
-	  (*_bfd_error_handler)
-	    (_("%B: ABI mismatch: linking %s module with previous %s modules"),
-	     ibfd,
-	     elf_mips_abi_name (ibfd),
-	     elf_mips_abi_name (obfd));
-	  ok = FALSE;
-	}
-      new_flags &= ~EF_MIPS_ABI;
-      old_flags &= ~EF_MIPS_ABI;
-    }
-
-  /* Compare ASEs.  Forbid linking MIPS16 and microMIPS ASE modules together
-     and allow arbitrary mixing of the remaining ASEs (retain the union).  */
-  if ((new_flags & EF_MIPS_ARCH_ASE) != (old_flags & EF_MIPS_ARCH_ASE))
-    {
-      int old_micro = old_flags & EF_MIPS_ARCH_ASE_MICROMIPS;
-      int new_micro = new_flags & EF_MIPS_ARCH_ASE_MICROMIPS;
-      int old_m16 = old_flags & EF_MIPS_ARCH_ASE_M16;
-      int new_m16 = new_flags & EF_MIPS_ARCH_ASE_M16;
-      int micro_mis = old_m16 && new_micro;
-      int m16_mis = old_micro && new_m16;
-
-      if (m16_mis || micro_mis)
-	{
-	  (*_bfd_error_handler)
-	    (_("%B: ASE mismatch: linking %s module with previous %s modules"),
-	     ibfd,
-	     m16_mis ? "MIPS16" : "microMIPS",
-	     m16_mis ? "microMIPS" : "MIPS16");
-	  ok = FALSE;
-	}
-
-      elf_elfheader (obfd)->e_flags |= new_flags & EF_MIPS_ARCH_ASE;
-
-      new_flags &= ~ EF_MIPS_ARCH_ASE;
-      old_flags &= ~ EF_MIPS_ARCH_ASE;
-    }
-
-  /* Compare NaN encodings.  */
-  if ((new_flags & EF_MIPS_NAN2008) != (old_flags & EF_MIPS_NAN2008))
-    {
-      _bfd_error_handler (_("%B: linking %s module with previous %s modules"),
-			  ibfd,
-			  (new_flags & EF_MIPS_NAN2008
-			   ? "-mnan=2008" : "-mnan=legacy"),
-			  (old_flags & EF_MIPS_NAN2008
-			   ? "-mnan=2008" : "-mnan=legacy"));
-      ok = FALSE;
-      new_flags &= ~EF_MIPS_NAN2008;
-      old_flags &= ~EF_MIPS_NAN2008;
-    }
-
-  /* Compare FP64 state.  */
-  if ((new_flags & EF_MIPS_FP64) != (old_flags & EF_MIPS_FP64))
-    {
-      _bfd_error_handler (_("%B: linking %s module with previous %s modules"),
-			  ibfd,
-			  (new_flags & EF_MIPS_FP64
-			   ? "-mfp64" : "-mfp32"),
-			  (old_flags & EF_MIPS_FP64
-			   ? "-mfp64" : "-mfp32"));
-      ok = FALSE;
-      new_flags &= ~EF_MIPS_FP64;
-      old_flags &= ~EF_MIPS_FP64;
-    }
-
-  /* Warn about any other mismatches */
-  if (new_flags != old_flags)
-    {
-      (*_bfd_error_handler)
-	(_("%B: uses different e_flags (0x%lx) fields than previous modules (0x%lx)"),
-	 ibfd, (unsigned long) new_flags,
-	 (unsigned long) old_flags);
-      ok = FALSE;
-    }
-
-  if (! ok)
+  if (!mips_elf_merge_obj_e_flags (ibfd, obfd))
     {
       bfd_set_error (bfd_error_bad_value);
       return FALSE;