Re: patches enable thumb disassembler to correctly dump thumb

[Nick Clifton <nickc at cygnus dot com>]

Hi Thomas,

: The inability of the arm/thumb disassembler to detect labels that
: were generated in ".code 16" (.thumb) mode -IF- labels were not
: specifically tagged using ".thumb_func" caused objdump to produce
: an incorrect disassembly dump listing. (Objdump would incorrectly
: use ARM mode for THUMB instructions - see testcase at end).

Thanks for submitting this patch.  There is only one problem with it -
the changes to bfd/elf32-arm.h to treat an ARM_STT_16BIT symbol as if
it were an ARM_STT_TFUNC symbol.  Since the code in this cases is
dealing with relocations for function calls, the ARM_STT_16BIT symbols
should be ignored, not treated as functions.

With this in mind, I have edited your patch slightly and checked it
in.

Cheers
	Nick

: ======================================================================
: 2000-01-18 Thomas de Lellis <tdel@windriver.com>
: 
:         * config/tc-arm.c (armadjust_symtab): If the assembler
:         is in '.code 16' (.thumb) mode but the label seen
:         in was not declared '.thumb_func' set the ST_INFO type
:         to the STT_ARM_16BIT mode.  We detect this flag
:         in the disassembler to allow objdump to correctly
:         disassemble thumb instructions under labels that
:         aren't '.thumb_func' labels.
:
: ======================================================================
: 2000-01-24  Thomas de Lellis  <tdel@wrs.com>
: 
:         * elf32-arm.h (bfd_elf32_arm_process_before_allocation)
:         Add STT_ARM_16BIT where ever STT_ARM_TFUNC used.
: 
:         * elf32-arm.h (elf32_arm_final_link_relocate)
:         Add STT_ARM_16BIT where ever STT_ARM_TFUNC used.
: 
:         * elf32-arm.h (elf32_arm_find_nearest_line)
:         Add STT_ARM_16BIT where ever STT_ARM_TFUNC used.
: 
:         * elf32-arm.h (elf32_arm_get_symbol_type)
:         If STT_ARM_16BIT mode and not object type
:         we return the STT_ARM_16ARM flag.  This is
:         because not everthing in a .code 16 block is
:         an executed instruction.
: 
: ======================================================================
: 2000-01-24  Thomas de Lellis  <tdel@windriver.com>
: 
:         * arm-dis.c (printf_insn_big_arm): Detect STT_ARM_16BIT
:         flag.  Instructs disassembler to correctly disassemble
:         thumb instructions which don't reside under labels
:         that have specifically been tagged '.thumb_func' in
:         gas.
:         
:         * arm-dis.c (printf_insn_little_arm): Ditto.
: 
: ======================================================================
: 2000-01-24  Thomas de Lellis  <tdel@windriver.com>
: 
:         * arm.h: Define STT_ARM_16BIT flag.  Denotes
:         label was defined in '.code 16' (.thumb) block
:         but was not declared '.thumb_func'.  Used mainly
:         by opcodes/arm-dis.c to instruct disassembler to
:         correctly disassemble thumb instructions under
:         non-.thumb_func labels.  Note: STT_HIPROC was
:         redefined for this.  (Maybe reuse STT_LOOS instead?)
: 
: ======================================================================