Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!ames!versatc!leadsv!practic!jfp
From: jfp@practic.UUCP (John F. Peters)
Newsgroups: gnu.utils.bug
Subject: gas-1.33(ns32k) fixups to .word and .int are byte-reversed
Message-ID: <40913@practic.UUCP>
Date: 31 May 89 19:08:41 GMT
Reply-To: jfp@practic.UUCP (John F. Peters)
Distribution: gnu
Organization: Practical Computing Inc., Sunnyvale
Lines: 182

DESCRIPTION:
    (1) .word and .int are fixed-up with bytes reversed 
    (2) "Probably harmless" used-before-set error in encode_operand(ns32k.c)
    (3) Minor typo in #if !defined(32032) (ns32k.c)

REPEAT-BY:
    Assemble this trivial program with a32k and inspect the output.  Note
    that ordinary integers appear (correctly) with lsb first, but expressions
    requiring fixup are rendered msb first. 
---------------------
.text

words:
	.word 1
	.word 2
	.word L1-L0
	.word L2-L0

ints:
	.int 1
	.int 2
	.int L1-L0
	.int L2-L0

labels:
L0:
	.byte 0
L1:
	.byte 0
L2:
	.byte 0
---------------------

FIX:
    32k has three sorts of constants:
	big-endian immediate	(md_number_to_imm)	im_disp==0
	big-endian displacement (md_number_to_disp)	im_disp==1
	little-endian		(md_number_to_chars)	im_disp==2

    Fixup_segment(write.c) decides among these three cases based on
    the fixS field fx_im_disp.  However, cons(read.c) builds a fixS
    using fix_new(write.c), which forces fx_im_disp to 0.

    A similar situation arises during "broken_word" handling in
    write_object_file(write.c).

    My fix is conditional compiling of calls to fix_new_ns32k(ns32k.c),
    with the im_disp parameter set to 2.  This is not such a desirable
    strategy since it introduces machine-dependence; a better approach
    would be machine-dependent procedures for constants and "broken_words".

*** Makefile.00	Fri May 12 11:45:32 1989
--- Makefile	Wed May 31 10:46:53 1989
***************
*** 50,59 ****
  # to include the mc68851 mmu coprocessor instructions un-comment
  # the next line, and comment out the following line.  (68020 only)
! OPTIONS = -Dm68851
! # OPTIONS =
! a:	a68
! 	@rm -f a
! 	@ln a68 a
! lint:	lint_68k
  
  # To make the VAX assembler compile as the default, un-comment the next five
--- 50,59 ----
  # to include the mc68851 mmu coprocessor instructions un-comment
  # the next line, and comment out the following line.  (68020 only)
! # OPTIONS = -Dm68851
! #OPTIONS =
! #a:	a68
! #	@rm -f a
! #	@ln a68 a
! #lint:	lint_68k
  
  # To make the VAX assembler compile as the default, un-comment the next five
***************
*** 75,83 ****
  # To make the ns32k assembler compile as the default, un comment the
  # next five lines, and comment out the 'a:' groups for the other assemblers.
! #OPTIONS =
! #a:	a32k
! #	@rm -f a
! #	@ln a32k a
! #lint:	lint_32k
  
  # To make the sparc assembler compile as the default, un comment the
--- 75,83 ----
  # To make the ns32k assembler compile as the default, un comment the
  # next five lines, and comment out the 'a:' groups for the other assemblers.
! OPTIONS = -DNS32032
! a:	a32k
! 	@rm -f a
! 	@ln a32k a
! lint:	lint_32k
  
  # To make the sparc assembler compile as the default, un comment the
*** ns32k.c.00	Thu May 11 12:35:16 1989
--- ns32k.c	Wed May 31 10:43:06 1989
***************
*** 227,231 ****
  };
  
! #if !defined(NS32032) && !defined(NS32032)
  #define NS32032
  #endif
--- 227,231 ----
  };
  
! #if !defined(NS32032) && !defined(NS32532)
  #define NS32032
  #endif
***************
*** 733,736 ****
--- 733,737 ----
      if (i>3) as_fatal("Internal error check ns32k-opcode.h");
      pcrel=0;
+     pcrel_adjust=0;
      tmp=0;
      switch (operandsP[(loop<<1)+1]) {

*** read.c.00	Wed Mar 29 08:40:40 1989
--- read.c	Wed May 31 10:32:37 1989
***************
*** 1300,1304 ****
--- 1300,1308 ----
    register segT		segment;
             expressionS	exp;
+ #if defined(NS32032) || defined(NS32532)
+   void	fix_new_ns32k();  /* 32k requires im_disp==2 for small-endian consts */
+ #else
    void	fix_new();
+ #endif
  
    /*
***************
*** 1395,1401 ****
--- 1399,1417 ----
  	    case SEG_TEXT:
  	    case SEG_DATA:
+ #if defined(NS32032) || defined(NS32532)
+ 	      /*
+ 	       * Ordinary (non-immed, non-disp) 32k constants are
+ 	       * little-endian, communicate this to fixup_segment
+ 	       * with im_disp == 2
+ 	       */
+ 	      fix_new_ns32k (frag_now, p - frag_now -> fr_literal, nbytes,
+ 		       exp . X_add_symbol, exp . X_subtract_symbol,
+ 		       exp . X_add_number, 0,
+ 		       0, 2, 0, 0);
+ #else
  	      fix_new (frag_now, p - frag_now -> fr_literal, nbytes,
  		       exp . X_add_symbol, exp . X_subtract_symbol,
  		       exp . X_add_number, 0);
+ #endif
  	      break;
  
*** write.c.00	Fri May 12 11:45:20 1989
--- write.c	Wed May 31 10:38:50 1989
***************
*** 429,433 ****
--- 429,444 ----
        for(lie=broken_words; lie; lie=lie->next_broken_word)
  	if(!lie->added) {
+ #if defined(NS32032) || defined(NS32532)
+ 	  void fix_new_ns32k();
+ 	  /*
+ 	   * Ordinary (non-immed, non-disp) 32k constants are
+ 	   * little-endian, communicate this to fixup_segment
+ 	   * with im_disp == 2
+ 	   */
+ 	  fix_new_ns32k(lie->frag,lie->word_goes_here - lie->frag->fr_literal,2,lie->add,lie->sub,lie->addnum,0,
+ 			0, 2, 0, 0);
+ #else
  	  fix_new(lie->frag,lie->word_goes_here - lie->frag->fr_literal,2,lie->add,lie->sub,lie->addnum,0);
+ #endif
  	  /* md_number_to_chars(lie->word_goes_here,
  			       lie->add->sy_value

*****************
-- 
jfp@practic.com   {uunet,sun,pyramid}!practic!jfp   408 749 8900