[committed] Make mips16_unextended_reference_p handle BLKmode

[Richard Sandiford]

This patch fixes an ICE on gcc.dg/pr48774.c for MIPS16, which triggered
while finding the rtx cost of a BLKmode memory.

Tested on mips64-linux-gnu and applied.

Richard


gcc/
        * config/mips/mips.c (mips16_unextended_reference_p): Test for BLKmode.

Index: gcc/config/mips/mips.c
===================================================================
--- gcc/config/mips/mips.c      2011-11-26 12:21:40.000000000 +0000
+++ gcc/config/mips/mips.c      2011-11-26 13:48:09.000000000 +0000
@@ -2163,7 +2163,7 @@ mips_lwxs_address_p (rtx addr)
 mips16_unextended_reference_p (enum machine_mode mode, rtx base,
                               unsigned HOST_WIDE_INT offset)
 {
-  if (offset % GET_MODE_SIZE (mode) == 0)
+  if (mode != BLKmode && offset % GET_MODE_SIZE (mode) == 0)
     {
       if (GET_MODE_SIZE (mode) == 4 && base == stack_pointer_rtx)
        return offset < 256U * GET_MODE_SIZE (mode);