MIPS/opcodes: Correct mixed MIPS16 and microMIPS disassembly

Mixing MIPS16 and microMIPS code in a single binary isn't usually
supported but GAS happily produces such code if requested.  However it
is not correctly disassembled even if a symbol table is available and
function symbols are correctly anotated with the ISA mode.  This is
because the ELF-header global microMIPS ASE flag takes precedence over
MIPS16 function annotation, causing them to be treated as regular MIPS
code.

Correct the problem by respecting function symbol anotation regardless
of the ELF-header flag.

	binutils/
	* testsuite/binutils-all/mips/mixed-mips16-micromips.d: New test.
	* testsuite/binutils-all/mips/mixed-mips16-micromips.s: New test
	source.
	* testsuite/binutils-all/mips/mips.exp: Run the new test.

	opcodes/
	* mips-dis.c (is_compressed_mode_p): Add `micromips_p' operand,
	replacing references to `micromips_ase' throughout.
	(_print_insn_mips): Don't use file-level microMIPS annotation to
	determine the disassembly mode with the symbol table.

diff --git a/binutils/ChangeLog b/binutils/ChangeLog
index 6eb3fa79acd3f21da8a7a3c4b6cedb368b2bcb20..c4bb34eb6b63ea038f4390b876c2856e819ad9ef 100644 (file)
--- a/binutils/ChangeLog
+++ b/binutils/ChangeLog
@@ -1,3 +1,10 @@
+2016-05-18  Maciej W. Rozycki  <macro@imgtec.com>
+
+       * testsuite/binutils-all/mips/mixed-mips16-micromips.d: New test.
+       * testsuite/binutils-all/mips/mixed-mips16-micromips.s: New test
+       source.
+       * testsuite/binutils-all/mips/mips.exp: Run the new test.
+
 2016-05-18  Nick Clifton  <nickc@redhat.com>
 
        * po/sv.po: Updated Swedish translation.

diff --git a/binutils/testsuite/binutils-all/mips/mips.exp b/binutils/testsuite/binutils-all/mips/mips.exp
index 5c939596b21daa8448e53d678fbeb17ddf91bc13..4dab9a60459ad091423ef2781798e3992e58548f 100644 (file)
--- a/binutils/testsuite/binutils-all/mips/mips.exp
+++ b/binutils/testsuite/binutils-all/mips/mips.exp
@@ -22,5 +22,6 @@ if ![istarget mips*-*-*] {
 if [is_elf_format] {
     run_dump_test "mixed-mips16"
     run_dump_test "mixed-micromips"
+    run_dump_test "mixed-mips16-micromips"
     run_dump_test "mips16-undecoded"
 }

diff --git a/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.d b/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.d
new file mode 100644 (file)
index 0000000..4a53dfb
--- /dev/null
+++ b/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.d
@@ -0,0 +1,30 @@
+#PROG: objcopy
+#objdump: -drt
+#name: Mixed MIPS16 and microMIPS disassembly
+
+# Test mixed-mode compressed disassembly.
+
+.*: +file format .*mips.*
+
+SYMBOL TABLE:
+#...
+[0-9a-f]+ g +F +\.text 0+00000c 0xf0 foo
+#...
+[0-9a-f]+ g +F +\.text 0+00000c 0x80 bar
+
+Disassembly of section \.text:
+[0-9a-f]+ <foo>:
+ +[0-9a-f]+:   b202            lw      v0,8 <\.foo\.data>
+ +[0-9a-f]+:   9a60            lw      v1,0\(v0\)
+ +[0-9a-f]+:   eb00            jr      v1
+ +[0-9a-f]+:   653b            move    t9,v1
+
+[0-9a-f]+ <\.foo\.data>:
+ +[0-9a-f]+:   4040 4040 0000 0000                         @@@@\.\.\.\.
+
+[0-9a-f]+ <bar>:
+ +[0-9a-f]+:   41a3 0000       lui     v1,0x0
+ +[0-9a-f]+:   ff23 0000       lw      t9,0\(v1\)
+ +[0-9a-f]+:   45b9            jrc     t9
+ +[0-9a-f]+:   0c00            nop
+       \.\.\.

diff --git a/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.s b/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.s
new file mode 100644 (file)
index 0000000..07dcceb
--- /dev/null
+++ b/binutils/testsuite/binutils-all/mips/mixed-mips16-micromips.s
@@ -0,0 +1,32 @@
+       .align  4, 0
+       .set    mips16
+       .globl  foo
+       .ent    foo
+foo:
+       lw      $v0, .foo.data
+       lw      $v1, 0($v0)
+       move    $t9, $v1
+       jr      $v1
+
+       .type   .foo.data, @object
+.foo.data:
+       .word   0x40404040
+       .size   .foo.data, . - .foo.data
+       .end    foo
+       .set    nomips16
+
+       .align  4, 0
+       .set    micromips
+       .globl  bar
+       .ent    bar
+bar:
+       lui     $v1, 0
+       lw      $t9, 0($v1)
+       jrc     $t9
+       nop
+       .end    bar
+       .set    nomicromips
+
+# Force some (non-delay-slot) zero bytes, to make 'objdump' print ...
+       .align  4, 0
+       .space  16

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index ce23ca181eb1894d8162d3742ec2bb417cbac6a0..680d2d89394081b8e722abf650ac69cdad5f7f5a 100644 (file)
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,10 @@
+2016-05-18  Maciej W. Rozycki  <macro@imgtec.com>
+
+       * mips-dis.c (is_compressed_mode_p): Add `micromips_p' operand,
+       replacing references to `micromips_ase' throughout.
+       (_print_insn_mips): Don't use file-level microMIPS annotation to
+       determine the disassembly mode with the symbol table.
+
 2016-05-13  Peter Bergner <bergner@vnet.ibm.com>
 
        * ppc-opc.c (IMM8): Use PPC_OPERAND_SIGNOPT.

diff --git a/opcodes/mips-dis.c b/opcodes/mips-dis.c
index 535c14a4d3b65d1823e7374784c269c49c65e79b..3f874e72f5e3443b7b88eb3da79d321bdef359bc 100644 (file)
--- a/opcodes/mips-dis.c
+++ b/opcodes/mips-dis.c
@@ -2268,33 +2268,33 @@ print_insn_micromips (bfd_vma memaddr, struct disassemble_info *info)
 }
 
 /* Return 1 if a symbol associated with the location being disassembled
-   indicates a compressed (MIPS16 or microMIPS) mode.  We iterate over
-   all the symbols at the address being considered assuming if at least
-   one of them indicates code compression, then such code has been
-   genuinely produced here (other symbols could have been derived from
-   function symbols defined elsewhere or could define data).  Otherwise,
-   return 0.  */
+   indicates a compressed mode, either MIPS16 or microMIPS, according to
+   MICROMIPS_P.  We iterate over all the symbols at the address being
+   considered assuming if at least one of them indicates code compression,
+   then such code has been genuinely produced here (other symbols could
+   have been derived from function symbols defined elsewhere or could
+   define data).  Otherwise, return 0.  */
 
 static bfd_boolean
-is_compressed_mode_p (struct disassemble_info *info)
+is_compressed_mode_p (struct disassemble_info *info, bfd_boolean micromips_p)
 {
   int i;
   int l;
 
   for (i = info->symtab_pos, l = i + info->num_symbols; i < l; i++)
     if (((info->symtab[i])->flags & BSF_SYNTHETIC) != 0
-       && ((!micromips_ase
+       && ((!micromips_p
             && ELF_ST_IS_MIPS16 ((*info->symbols)->udata.i))
-           || (micromips_ase
+           || (micromips_p
                && ELF_ST_IS_MICROMIPS ((*info->symbols)->udata.i))))
       return 1;
     else if (bfd_asymbol_flavour (info->symtab[i]) == bfd_target_elf_flavour
              && info->symtab[i]->section == info->section)
       {
        elf_symbol_type *symbol = (elf_symbol_type *) info->symtab[i];
-       if ((!micromips_ase
+       if ((!micromips_p
             && ELF_ST_IS_MIPS16 (symbol->internal_elf_sym.st_other))
-           || (micromips_ase
+           || (micromips_p
                && ELF_ST_IS_MICROMIPS (symbol->internal_elf_sym.st_other)))
          return 1;
       }
@@ -2313,7 +2313,6 @@ _print_insn_mips (bfd_vma memaddr,
                  struct disassemble_info *info,
                  enum bfd_endian endianness)
 {
-  int (*print_insn_compr) (bfd_vma, struct disassemble_info *);
   bfd_byte buffer[INSNLEN];
   int status;
 
@@ -2325,18 +2324,23 @@ _print_insn_mips (bfd_vma memaddr,
   if (info->mach == bfd_mach_mips_micromips)
     return print_insn_micromips (memaddr, info);
 
-  print_insn_compr = !micromips_ase ? print_insn_mips16 : print_insn_micromips;
-
 #if 1
   /* FIXME: If odd address, this is CLEARLY a compressed instruction.  */
   /* Only a few tools will work this way.  */
   if (memaddr & 0x01)
-    return print_insn_compr (memaddr, info);
+    {
+      if (micromips_ase)
+       return print_insn_micromips (memaddr, info);
+      else
+       return print_insn_mips16 (memaddr, info);
+    }
 #endif
 
 #if SYMTAB_AVAILABLE
-  if (is_compressed_mode_p (info))
-    return print_insn_compr (memaddr, info);
+  if (is_compressed_mode_p (info, TRUE))
+    return print_insn_micromips (memaddr, info);
+  if (is_compressed_mode_p (info, FALSE))
+    return print_insn_mips16 (memaddr, info);
 #endif
 
   status = (*info->read_memory_func) (memaddr, buffer, INSNLEN, info);