[Bug target/49781] [x32] Unnecessary lea in x32 mode

["ubizjak at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49781

--- Comment #16 from Uros Bizjak <ubizjak at gmail dot com> 2011-08-04 18:49:32 UTC ---
(In reply to comment #14)

> /export/build/gnu/gcc-x32-test/release/usr/gcc-4.7.0-x32/bin/gcc -mx32  
> -std=gnu99 -fgnu89-inline -O2    -S testcase.c
> ....
> testcase.c:634:2: internal compiler error: Segmentation fault
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <http://gcc.gnu.org/bugs.html> for instructions.

Sometimes, a subreg is returned as base or index register.  This patch strips
subregs and fixes ICE (I wonder, why the ICE didn't show earlier):

Index: i386.c
===================================================================
--- i386.c    (revision 177411)
+++ i386.c    (working copy)
@@ -14088,6 +14101,20 @@

   gcc_assert (ok);

+  if (parts.base && GET_CODE (parts.base) == SUBREG)
+    {
+      rtx tmp = SUBREG_REG (parts.base);
+      parts.base = simplify_subreg (GET_MODE (parts.base),
+                    tmp, GET_MODE (tmp), 0);
+    }
+
+  if (parts.index && GET_CODE (parts.index) == SUBREG)
+    {
+      rtx tmp = SUBREG_REG (parts.index);
+      parts.index = simplify_subreg (GET_MODE (parts.index),
+                     tmp, GET_MODE (tmp), 0);
+    }
+
   base = parts.base;
   index = parts.index;
   disp = parts.disp;

However, I think we should hanlde plus (zero_extend (...addr...)(const_int))
offsetable operands, too. Otherwise there will be no benefit for SSE
operands...