From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Henderson <rth@redhat.com>
To: Marc.Espie@liafa.jussieu.fr
Cc: gcc@gcc.gnu.org
Subject: openbsd gotoff workaround
Date: Mon, 10 Sep 2001 18:18:00 -0000
Message-id: <20010910181833.A11350@redhat.com>
References: <877kv7dp67.fsf@kaka.blahonga.org> <Pine.LNX.4.33.0109101655330.16107-100000@host140.cambridge.redhat.com> <20010910184528.A10185@schutzenberger.liafa.jussieu.fr>
X-SW-Source: 2001-09/msg00397.html

On Mon, Sep 10, 2001 at 06:45:28PM +0200, Marc Espie wrote:
> We can't ship a compiler that doesn't even compile OpenBSD i386 pic
> code correctly (no news on my GOT/GOTOFF problems, rth ?).

Try this.


r~



Index: i386.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.c,v
retrieving revision 1.211.2.14
diff -c -p -d -r1.211.2.14 i386.c
*** i386.c	2001/08/06 21:26:24	1.211.2.14
--- i386.c	2001/09/11 01:15:36
*************** int ix86_align_loops;
*** 417,423 ****
--- 417,428 ----
  
  /* Power of two alignment for non-loop jumps.  */
  int ix86_align_jumps;
+ 
+ /* Prefix built by ASM_GENERATE_INTERNAL_LABEL.  */
+ static int internal_label_prefix[16];
+ static int internal_label_prefix_len;
  
+ static int local_symbolic_operand PARAMS ((rtx, enum machine_mode));
  static void output_pic_addr_const PARAMS ((FILE *, rtx, int));
  static void put_condition_code PARAMS ((enum rtx_code, enum machine_mode,
  				       int, int, FILE *));
*************** override_options ()
*** 693,698 ****
--- 698,712 ----
       on by -msse.  */
    if (TARGET_SSE)
      target_flags |= MASK_MMX;
+ 
+   /* Figure out what ASM_GENERATE_INTERNAL_LABEL builds as a prefix.  */
+   {
+     char *p;
+     ASM_GENERATE_INTERNAL_LABEL (internal_label_prefix, "LX", 0);
+     p = strchr (internal_label_prefix, 'X');
+     internal_label_prefix_len = p - internal_label_prefix;
+     *p = '\0';
+   }
  }
  
  /* A C statement (sans semicolon) to choose the order in which to
*************** pic_symbolic_operand (op, mode)
*** 1128,1133 ****
--- 1142,1181 ----
    return 0;
  }
  
+ /* Return true if OP is a symbolic operand that resolves locally.  */
+ 
+ static int
+ local_symbolic_operand (op, mode)
+      rtx op;
+      enum machine_mode mode ATTRIBUTE_UNUSED;
+ {
+   if (GET_CODE (op) == LABEL_REF)
+     return 1;
+ 
+   if (GET_CODE (op) == CONST
+       && GET_CODE (XEXP (op, 0)) == PLUS
+       && GET_CODE (XEXP (XEXP (op, 0), 1)) == CONST_INT)
+     op = XEXP (XEXP (op, 0), 0);
+ 
+   if (GET_CODE (op) != SYMBOL_REF)
+     return 0;
+ 
+   /* These we've been told are local by varasm and encode_section_info
+      respectively.  */
+   if (CONSTANT_POOL_ADDRESS_P (op) || SYMBOL_REF_FLAG (op))
+     return 1;
+ 
+   /* There is, however, a not insubstantial body of code in the rest of
+      the compiler that assumes it can just stick the results of 
+      ASM_GENERATE_INTERNAL_LABEL in a symbol_ref and have done.  */
+ 
+   if (strncmp (XSTR (op, 0), internal_label_prefix,
+ 	       internal_label_prefix_len) == 0)
+     return 1;
+ 
+   return 0;
+ }
+ 
  /* Test for a valid operand for a call instruction.  Don't allow the
     arg pointer register or virtual regs since they may decay into
     reg + const, which the patterns can't handle.  */
*************** legitimize_pic_address (orig, reg)
*** 2767,2776 ****
    rtx new = orig;
    rtx base;
  
!   if (GET_CODE (addr) == LABEL_REF
!       || (GET_CODE (addr) == SYMBOL_REF
! 	  && (CONSTANT_POOL_ADDRESS_P (addr)
! 	      || SYMBOL_REF_FLAG (addr))))
      {
        /* This symbol may be referenced via a displacement from the PIC
  	 base address (@GOTOFF).  */
--- 2815,2821 ----
    rtx new = orig;
    rtx base;
  
!   if (local_symbolic_operand (addr, Pmode))
      {
        /* This symbol may be referenced via a displacement from the PIC
  	 base address (@GOTOFF).  */
*************** legitimize_pic_address (orig, reg)
*** 2822,2831 ****
  
  	  /* Check first to see if this is a constant offset from a @GOTOFF
  	     symbol reference.  */
! 	  if ((GET_CODE (op0) == LABEL_REF
! 	       || (GET_CODE (op0) == SYMBOL_REF
! 		   && (CONSTANT_POOL_ADDRESS_P (op0)
! 		       || SYMBOL_REF_FLAG (op0))))
  	      && GET_CODE (op1) == CONST_INT)
  	    {
  	      current_function_uses_pic_offset_table = 1;
--- 2867,2873 ----
  
  	  /* Check first to see if this is a constant offset from a @GOTOFF
  	     symbol reference.  */
! 	  if (local_symbolic_operand (op0, Pmode))
  	      && GET_CODE (op1) == CONST_INT)
  	    {
  	      current_function_uses_pic_offset_table = 1;