[binutils-gdb] MIPS/BFD: Add microMIPS annotation to LA25 stub symbols

[Maciej W.Rozycki <macro at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a848a2271b9bd45400e875a2518ebedf1efba2fa

commit a848a2271b9bd45400e875a2518ebedf1efba2fa
Author: Maciej W. Rozycki <macro@imgtec.com>
Date:   Wed Aug 10 20:03:02 2016 +0100

    MIPS/BFD: Add microMIPS annotation to LA25 stub symbols
    
    Fix a problem with missing microMIPS symbol annotation with microMIPS
    LA25 stub symbols.  The consequence of the issue is these symbols appear
    in the symbol table as regular MIPS symbols with the ISA bit set, as
    shown with the example below:
    
    $ cat la25a.s
    	.abicalls
    
    	.global	f1
    	.ent	f1
    f1:
    	.set	noreorder
    	.cpload	$25
    	.set	reorder
    	.option	pic0
    	jal	f2
    	.option	pic2
    	jr	$31
    	.end	f1
    
    	.global	f2
    	.ent	f2
    f2:
    	jr	$31
    	.end	f2
    $ cat la25b.s
    	.abicalls
    	.option	pic0
    
    	.global	__start
    	.ent	__start
    __start:
    	jal	f1
    	jal	f2
    	.end	__start
    $ as -mmicromips -32 -EB -o la25a.o la25a.s
    $ as -mmicromips -32 -EB -o la25b.o la25b.s
    $ ld -melf32btsmip -o la25 la25a.o la25b.o
    $ readelf -s la25
    
    Symbol table '.symtab' contains 18 entries:
       Num:    Value  Size Type    Bind   Vis      Ndx Name
         0: 00000000     0 NOTYPE  LOCAL  DEFAULT  UND
         1: 00400098     0 SECTION LOCAL  DEFAULT    1
         2: 004000b0     0 SECTION LOCAL  DEFAULT    2
         3: 004000d0     0 SECTION LOCAL  DEFAULT    3
         4: 00000000     0 SECTION LOCAL  DEFAULT    4
         5: 00000000     0 SECTION LOCAL  DEFAULT    5
         6: 00418110     0 NOTYPE  LOCAL  DEFAULT    3 _gp
         7: 004000e1    16 FUNC    LOCAL  DEFAULT    3 .pic.f1
         8: 004000d1    16 FUNC    LOCAL  DEFAULT    3 .pic.f2
         9: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _fdata
        10: 00400110    16 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 __start
        11: 00400106     2 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 f2
        12: 004000d0     0 NOTYPE  GLOBAL DEFAULT    3 _ftext
        13: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 __bss_start
        14: 004000f0    22 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 f1
        15: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _edata
        16: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _end
        17: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _fbss
    $
    
    where microMIPS annotation is missing for `.pic.f1' and `.pic.f2' even
    though these stubs are associated with microMIPS functions `f1' and `f2'
    respectively.
    
    Add the missing annotation then, by copying it from the function symbol
    an LA25 stub is associated with, correcting the example above:
    
    $ readelf -s la25
    
    Symbol table '.symtab' contains 18 entries:
       Num:    Value  Size Type    Bind   Vis      Ndx Name
         0: 00000000     0 NOTYPE  LOCAL  DEFAULT  UND
         1: 00400098     0 SECTION LOCAL  DEFAULT    1
         2: 004000b0     0 SECTION LOCAL  DEFAULT    2
         3: 004000d0     0 SECTION LOCAL  DEFAULT    3
         4: 00000000     0 SECTION LOCAL  DEFAULT    4
         5: 00000000     0 SECTION LOCAL  DEFAULT    5
         6: 00418110     0 NOTYPE  LOCAL  DEFAULT    3 _gp
         7: 004000e0    16 FUNC    LOCAL  DEFAULT [MICROMIPS]     3 .pic.f1
         8: 004000d0    16 FUNC    LOCAL  DEFAULT [MICROMIPS]     3 .pic.f2
         9: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _fdata
        10: 00400110    16 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 __start
        11: 00400106     2 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 f2
        12: 004000d0     0 NOTYPE  GLOBAL DEFAULT    3 _ftext
        13: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 __bss_start
        14: 004000f0    22 FUNC    GLOBAL DEFAULT [MICROMIPS]     3 f1
        15: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _edata
        16: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _end
        17: 00410120     0 NOTYPE  GLOBAL DEFAULT    3 _fbss
    $
    
    This problem has been there since the beginning of microMIPS support:
    
    commit df58fc944dbc6d5efd8d3826241b64b6af22f447
    Author: Richard Sandiford <rdsandiford@googlemail.com>
    Date:   Sun Jul 24 14:20:15 2011 +0000
    
    <https://sourceware.org/ml/binutils/2011-07/msg00198.html>, ("MIPS:
    microMIPS ASE support").
    
    	bfd/
    	* elfxx-mips.c (mips_elf_create_stub_symbol): For a microMIPS
    	stub also add STO_MICROMIPS annotation.

Diff:
---
 bfd/ChangeLog    | 5 +++++
 bfd/elfxx-mips.c | 5 ++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index ac8230d..3ddafcb 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,10 @@
 2016-08-10  Maciej W. Rozycki  <macro@imgtec.com>
 
+	* elfxx-mips.c (mips_elf_create_stub_symbol): For a microMIPS
+	stub also add STO_MICROMIPS annotation.
+
+2016-08-10  Maciej W. Rozycki  <macro@imgtec.com>
+
 	* elfxx-mips.c (mips_elf_calculate_relocation): Set the ISA bit
 	in microMIPS LA25 stub references.
 
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c
index cfb9a52..6690428 100644
--- a/bfd/elfxx-mips.c
+++ b/bfd/elfxx-mips.c
@@ -1578,12 +1578,13 @@ mips_elf_create_stub_symbol (struct bfd_link_info *info,
 			     const char *prefix, asection *s, bfd_vma value,
 			     bfd_vma size)
 {
+  bfd_boolean micromips_p = ELF_ST_IS_MICROMIPS (h->root.other);
   struct bfd_link_hash_entry *bh;
   struct elf_link_hash_entry *elfh;
   char *name;
   bfd_boolean res;
 
-  if (ELF_ST_IS_MICROMIPS (h->root.other))
+  if (micromips_p)
     value |= 1;
 
   /* Create a new symbol.  */
@@ -1601,6 +1602,8 @@ mips_elf_create_stub_symbol (struct bfd_link_info *info,
   elfh->type = ELF_ST_INFO (STB_LOCAL, STT_FUNC);
   elfh->size = size;
   elfh->forced_local = 1;
+  if (micromips_p)
+    elfh->other = ELF_ST_SET_MICROMIPS (elfh->other);
   return TRUE;
 }