re PR target/32406 (MIPS: FAIL in nestfunc-6.c at -O3)

gcc/
	PR target/32406
	* builtins.c (expand_builtin_nonlocal_goto): Also emit a use
	of GP register, if valid and fixed.

	Revert:
	2007-06-21  David Daney  <ddaney@avtrex.com>

	PR target/32406
	* config/mips/mips.md (define_constants): Rename UNSPEC_EH_RECEIVER
	to UNSPEC_NONLOCAL_GOTO_RECEIVER globally.
	(exception_receiver): Renamed to ...
	(nonlocal_goto_receiver): ... this.

From-SVN: r130493

gcc/ChangeLog

+2007-11-28  Richard Sandiford  <rsandifo@nildram.co.uk>
+
+	PR target/32406
+	* builtins.c (expand_builtin_nonlocal_goto): Also emit a use
+	of GP register, if valid and fixed.
+
+	Revert:
+	2007-06-21  David Daney  <ddaney@avtrex.com>
+
+	PR target/32406
+	* config/mips/mips.md (define_constants): Rename UNSPEC_EH_RECEIVER
+	to UNSPEC_NONLOCAL_GOTO_RECEIVER globally.
+	(exception_receiver): Renamed to ...
+	(nonlocal_goto_receiver): ... this.
+
 2007-11-27  H.J. Lu  <hongjiu.lu@intel.com>
 	    Joey Ye <joey.ye@intel.com>
 

gcc/builtins.c

@@ -909,6 +909,20 @@ expand_builtin_nonlocal_goto (tree exp)
 	 not clear if really needed.  */
       emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx));
       emit_insn (gen_rtx_USE (VOIDmode, stack_pointer_rtx));
+
+      /* If the architecture is using a GP register, we must
+	 conservatively assume that the target function makes use of it.
+	 The prologue of functions with nonlocal gotos must therefore
+	 initialize the GP register to the appropriate value, and we
+	 must then make sure that this value is live at the point
+	 of the jump.  (Note that this doesn't necessarily apply
+	 to targets with a nonlocal_goto pattern; they are free
+	 to implement it in their own way.  Note also that this is
+	 a no-op if the GP register is a global invariant.)  */
+      if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM
+	  && fixed_regs[PIC_OFFSET_TABLE_REGNUM])
+	emit_insn (gen_rtx_USE (VOIDmode, pic_offset_table_rtx));
+
       emit_indirect_jump (r_label);
     }
 

gcc/config/mips/mips.md

@@ -30,7 +30,7 @@
    (UNSPEC_GET_FNADDR		 3)
    (UNSPEC_BLOCKAGE		 4)
    (UNSPEC_CPRESTORE		 5)
-   (UNSPEC_NONLOCAL_GOTO_RECEIVER 6)
+   (UNSPEC_EH_RECEIVER		 6)
    (UNSPEC_EH_RETURN		 7)
    (UNSPEC_CONSTTABLE_INT	 8)
    (UNSPEC_CONSTTABLE_FLOAT	 9)
@@ -5598,9 +5598,9 @@
   DONE;
 })
 
-(define_insn_and_split "nonlocal_goto_receiver"
+(define_insn_and_split "exception_receiver"
   [(set (reg:SI 28)
-	(unspec_volatile:SI [(const_int 0)] UNSPEC_NONLOCAL_GOTO_RECEIVER))]
+	(unspec_volatile:SI [(const_int 0)] UNSPEC_EH_RECEIVER))]
   "TARGET_CALL_CLOBBERED_GP"
   "#"
   "&& reload_completed"