Enhance powerpc ld -r --relax

[binutils-gdb.git] / bfd / elf32-ppc.c

diff --git a/bfd/elf32-ppc.c b/bfd/elf32-ppc.c
index 30246740076406355911186ff6ab5db2c1507fe4..c289eebe316509d6fbfa9b1ac3e12b78829b0ea8 100644 (file)
--- a/bfd/elf32-ppc.c
+++ b/bfd/elf32-ppc.c
@@ -2411,16 +2411,18 @@ ppc_elf_write_core_note (bfd *abfd, char *buf, int *bufsiz, int note_type, ...)
        va_start (ap, note_type);
        memset (data, 0, sizeof (data));
        strncpy (data + 32, va_arg (ap, const char *), 16);
+#if GCC_VERSION == 8000 || GCC_VERSION == 8001
        DIAGNOSTIC_PUSH;
-       /* GCC 8.1 warns about 80 equals destination size with
+       /* GCC 8.0 and 8.1 warn about 80 equals destination size with
           -Wstringop-truncation:
           https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643
         */
-#if GCC_VERSION == 8001
        DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION;
 #endif
        strncpy (data + 48, va_arg (ap, const char *), 80);
+#if GCC_VERSION == 8000 || GCC_VERSION == 8001
        DIAGNOSTIC_POP;
+#endif
        va_end (ap);
        return elfcore_write_note (abfd, buf, bufsiz,
                                   "CORE", note_type, data, sizeof (data));
@@ -7384,12 +7386,10 @@ ppc_elf_relax_section (bfd *abfd,
            {
              if (tsec != NULL)
                ;
-             else if (isym->st_shndx == SHN_UNDEF)
-               tsec = bfd_und_section_ptr;
              else if (isym->st_shndx == SHN_ABS)
                tsec = bfd_abs_section_ptr;
-             else if (isym->st_shndx == SHN_COMMON)
-               tsec = bfd_com_section_ptr;
+             else
+               continue;
 
              toff = isym->st_value;
              sym_type = ELF_ST_TYPE (isym->st_info);
@@ -7531,6 +7531,17 @@ ppc_elf_relax_section (bfd *abfd,
          if (tsec == isec)
            continue;
 
+         /* toff is used for the symbol index when the symbol is
+            undefined and we're doing a relocatable link, so we can't
+            support addends.  It would be possible to do so by
+            putting the addend in one_branch_fixup but addends on
+            branches are rare so it hardly seems worth supporting.  */
+         if (bfd_link_relocatable (link_info)
+             && tsec == bfd_und_section_ptr
+             && r_type != R_PPC_PLTREL24
+             && irel->r_addend != 0)
+           continue;
+
          /* There probably isn't any reason to handle symbols in
             SEC_MERGE sections;  SEC_MERGE doesn't seem a likely
             attribute for a code section, and we are only looking at
@@ -7554,7 +7565,8 @@ ppc_elf_relax_section (bfd *abfd,
                 a section symbol should not include the addend;  Such an
                 access is presumed to be an offset from "sym";  The
                 location of interest is just "sym".  */
-             if (sym_type == STT_SECTION)
+             if (sym_type == STT_SECTION
+                 && r_type != R_PPC_PLTREL24)
                toff += irel->r_addend;
 
              toff
@@ -7562,7 +7574,8 @@ ppc_elf_relax_section (bfd *abfd,
                                              elf_section_data (tsec)->sec_info,
                                              toff);
 
-             if (sym_type != STT_SECTION)
+             if (sym_type != STT_SECTION
+                 && r_type != R_PPC_PLTREL24)
                toff += irel->r_addend;
            }
          /* PLTREL24 addends are special.  */
@@ -7579,6 +7592,16 @@ ppc_elf_relax_section (bfd *abfd,
 
          roff = irel->r_offset;
 
+         /* Avoid creating a lot of unnecessary fixups when
+            relocatable if the output section size is such that a
+            fixup can be created at final link.
+            The max_branch_offset adjustment allows for some number
+            of other fixups being needed at final link.  */
+         if (bfd_link_relocatable (link_info)
+             && (isec->output_section->rawsize - (isec->output_offset + roff)
+                 < max_branch_offset - (max_branch_offset >> 4)))
+           continue;
+
          /* If the branch is in range, no need to do anything.  */
          if (tsec != bfd_und_section_ptr
              && (!bfd_link_relocatable (link_info)