mips-tdep.c: FP varargs fixes

["Maciej W. Rozycki" <macro@mips.com>]

Hello,

 The following changes fix the following test case failure:

print find_max_double(5,1.0,17.0,2.0,3.0,4.0)
find_max(5, -0.000000, 0.000000, 0.000000, 0.000000, 0.000000) returns 0.000000
$5 = 5.3101701311997171e-315
(gdb) FAIL: gdb.base/varargs.exp: print find_max_double(5,1.0,17.0,2.0,3.0,4.0)

This change has been tested natively for mips-unknown-linux-gnu and 
remotely for mipsisa32-sde-elf, using mips-sim-sde32/-EB and 
mips-sim-sde32/-EL as the targets, removing the failure for all.

2007-03-23  Nigel Stephens  <nigel@mips.com>
            Maciej W. Rozycki  <macro@mips.com>

	* mips-tdep.c (mips_o32_push_dummy_call): Take account of
	argument alignment requirements when calculating stack space
	required.  When aligning an arg register to eight bytes
	boundary, align stack_offset too.  Write floating-point
	arguments to the appropriate integer register, if we're not
	passing in a floating point register.

 OK to apply?

  Maciej

12100-0.diff
Index: binutils-quilt/src/gdb/mips-tdep.c
===================================================================
--- binutils-quilt.orig/src/gdb/mips-tdep.c	2007-03-23 14:21:18.000000000 +0000
+++ binutils-quilt/src/gdb/mips-tdep.c	2007-03-23 14:25:57.000000000 +0000
@@ -3071,8 +3071,16 @@
 
   /* Now make space on the stack for the args.  */
   for (argnum = 0; argnum < nargs; argnum++)
-    len += align_up (TYPE_LENGTH (value_type (args[argnum])),
-		     mips_stack_argsize (gdbarch));
+    {
+      struct type *arg_type = check_typedef (value_type (args[argnum]));
+      int arglen = TYPE_LENGTH (arg_type);
+      /* Align to double-word if necessary.  */
+      if (mips_abi_regsize (gdbarch) < 8
+	  && mips_type_needs_double_align (arg_type))
+	len = align_up (len, mips_stack_argsize (gdbarch) * 2);
+      /* Allocate space on the stack.  */
+      len += align_up (arglen, mips_stack_argsize (gdbarch));
+    }
   sp -= align_up (len, 16);
 
   if (mips_debug)
@@ -3208,7 +3216,10 @@
 	      && mips_type_needs_double_align (arg_type))
 	    {
 	      if ((argreg & 1))
-		argreg++;
+		{
+		  argreg++;
+		  stack_offset += mips_abi_regsize (gdbarch);
+		}
 	    }
 	  /* Note: Floating-point values that didn't fit into an FP
 	     register are only written to memory.  */
@@ -3272,7 +3283,7 @@
 	      /* Write this portion of the argument to a general
 	         purpose register.  */
 	      if (argreg <= MIPS_LAST_ARG_REGNUM
-		  && !fp_register_arg_p (typecode, arg_type))
+		  /*&& !fp_register_arg_p (typecode, arg_type)*/)
 		{
 		  LONGEST regval = extract_signed_integer (val, partial_len);
 		  /* Value may need to be sign extended, because