Patch to fix recent MIPS gas reloc breakage

[Richard Sandiford <rsandifo at redhat dot com>]

Brown paper bag time ;(.  The first of my two recent gas
patches broke newlib because we no longer accepted things like:

        lw      $4,((10 + 4) * 4)($4)

Thanks to Graham for the heads-up.

The problem was that my_getSmallExpression() was eating all
leading open brackets, regardless of whether they belonged
to reloc expressions.  I _knew_ that that "break" meant trouble...

Patch tested on mips64-elf (binutils, gas, ld), no regressions.  I'm
running a mips64-elf gcc test as well: so far newlib & libgloss have
built successfully.  OK to install if the gcc tests pass?

Really sorry for the breakage.

Richard


	* config/tc-mips.c (my_getSmallExpression): Rework bracket handling.

testsuite/
	* gas/mips/expr1.[sd]: New test.
	* gas/mips/mips.exp: Run it.

Index: config/tc-mips.c
===================================================================
RCS file: /cvs/src/src/gas/config/tc-mips.c,v
retrieving revision 1.190
diff -c -d -p -F^[(a-zA-Z0-9_^#] -r1.190 tc-mips.c
*** config/tc-mips.c	2 Feb 2003 19:37:20 -0000	1.190
--- config/tc-mips.c	7 Feb 2003 13:13:10 -0000
*************** my_getSmallExpression (ep, reloc, str)
*** 10020,10055 ****
  {
    bfd_reloc_code_real_type reversed_reloc[3];
    size_t reloc_index, i;
!   int bracket_depth;
! 
!   reloc_index = 0;
!   bracket_depth = 0;
  
    /* Search for the start of the main expression, recoding relocations
!      in REVERSED_RELOC.  */
!   for (;;)
      {
!       if (*str == '(')
! 	bracket_depth++, str++;
!       else if (*str == ' ' || *str == '\t')
! 	str++;
!       else if (*str == '%'
! 	       && reloc_index < (HAVE_NEWABI ? 3 : 1)
! 	       && parse_relocation (&str, &reversed_reloc[reloc_index]))
! 	reloc_index++;
!       else
! 	break;
      }
  
!   my_getExpression (ep, str);
    str = expr_end;
  
    /* Match every open bracket.  */
!   while (bracket_depth > 0 && (*str == ')' || *str == ' ' || *str == '\t'))
      if (*str++ == ')')
!       bracket_depth--;
  
!   if (bracket_depth > 0)
      as_bad ("unclosed '('");
  
    expr_end = str;
--- 10018,10057 ----
  {
    bfd_reloc_code_real_type reversed_reloc[3];
    size_t reloc_index, i;
!   int crux_depth, str_depth;
!   char *crux;
  
    /* Search for the start of the main expression, recoding relocations
!      in REVERSED_RELOC.  End the loop with CRUX pointing to the start
!      of the main expression and with CRUX_DEPTH containing the number
!      of open brackets at that point.  */
!   reloc_index = -1;
!   str_depth = 0;
!   do
      {
!       reloc_index++;
!       crux = str;
!       crux_depth = str_depth;
! 
!       /* Skip over whitespace and brackets, keeping count of the number
! 	 of brackets.  */
!       while (*str == ' ' || *str == '\t' || *str == '(')
! 	if (*str++ == '(')
! 	  str_depth++;
      }
+   while (*str == '%'
+ 	 && reloc_index < (HAVE_NEWABI ? 3 : 1)
+ 	 && parse_relocation (&str, &reversed_reloc[reloc_index]));
  
!   my_getExpression (ep, crux);
    str = expr_end;
  
    /* Match every open bracket.  */
!   while (crux_depth > 0 && (*str == ')' || *str == ' ' || *str == '\t'))
      if (*str++ == ')')
!       crux_depth--;
  
!   if (crux_depth > 0)
      as_bad ("unclosed '('");
  
    expr_end = str;
Index: testsuite/gas/mips/mips.exp
===================================================================
RCS file: /cvs/src/src/gas/testsuite/gas/mips/mips.exp,v
retrieving revision 1.59
diff -c -d -p -F^[(a-zA-Z0-9_^#] -r1.59 mips.exp
*** testsuite/gas/mips/mips.exp	2 Feb 2003 19:37:20 -0000	1.59
--- testsuite/gas/mips/mips.exp	7 Feb 2003 13:13:10 -0000
*************** if { [istarget mips*-*-*] } then {
*** 618,623 ****
--- 618,624 ----
  	    run_dump_test "${tmips}mips${el}16-f"
  	}
  	run_dump_test "elf-consthilo"
+ 	run_dump_test "expr1"
      }
  
      if $has_newabi {
*** /dev/null	Thu Apr 11 15:25:15 2002
--- testsuite/gas/mips/expr1.d	Fri Feb  7 13:12:22 2003
***************
*** 0 ****
--- 1,19 ----
+ #as: -march=mips2 -mabi=32
+ #objdump: -M gpr-names=numeric -dr
+ #name: MIPS expression 1
+ 
+ .*:     file format .*
+ 
+ Disassembly of section \.text:
+ 
+ 0+00 <foo>:
+    0:	8c840000 	lw	\$4,0\(\$4\)
+ 			0: R_MIPS_LO16	foo
+    4:	8c840038 	lw	\$4,56\(\$4\)
+    8:	8c840008 	lw	\$4,8\(\$4\)
+ 			8: R_MIPS_LO16	foo
+    c:	8c840008 	lw	\$4,8\(\$4\)
+ 			c: R_MIPS_LO16	foo
+   10:	8c840008 	lw	\$4,8\(\$4\)
+ 			10: R_MIPS_LO16	foo
+ 	\.\.\.
*** /dev/null	Thu Apr 11 15:25:15 2002
--- testsuite/gas/mips/expr1.s	Fri Feb  7 13:08:24 2003
***************
*** 0 ****
--- 1,10 ----
+ 	.globl	foo
+ 	.ent	foo
+ foo:
+ 	lw	$4,%lo(foo)($4)
+ 	lw	$4,((10 + 4) * 4)($4)
+ 	lw	$4,%lo (2 * 4) + foo($4)
+ 	lw	$4,%lo((2 * 4) + foo)($4)
+ 	lw	$4,(((%lo ((2 * 4) + foo))))($4)
+ 	.space	64
+ 	.end	foo