[Bug middle-end/55597] [4.8 Regression] internal compiler error: in plus_constant, at explow.c:88

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55597

--- Comment #12 from Uros Bizjak <ubizjak at gmail dot com> 2012-12-06 20:14:06 UTC ---
(In reply to comment #11)
 > It works.  Thanks.
> 
> Unfortunately it creates GC garbage often unnecessary, when it won't be used at
> all.

I agree. Let's keep zext together with their users:

--cut here--
Index: i386.c
===================================================================
--- i386.c      (revision 194263)
+++ i386.c      (working copy)
@@ -12785,6 +12785,9 @@
          tp = get_thread_pointer (Pmode, true);
          dest = force_reg (Pmode, gen_rtx_PLUS (Pmode, tp, dest));

+         if (GET_MODE (x) != Pmode)
+           x = gen_rtx_ZERO_EXTEND (Pmode, x);
+
          set_unique_reg_note (get_last_insn (), REG_EQUAL, x);
        }
       else
@@ -12793,15 +12796,20 @@

          if (TARGET_64BIT)
            {
-             rtx rax = gen_rtx_REG (Pmode, AX_REG), insns;
+             rtx rax = gen_rtx_REG (Pmode, AX_REG);
+             rtx insns;

              start_sequence ();
-             emit_call_insn (ix86_gen_tls_global_dynamic_64 (rax, x,
-                                                             caddr));
+             emit_call_insn
+               (ix86_gen_tls_global_dynamic_64 (rax, x, caddr));
              insns = get_insns ();
              end_sequence ();

              RTL_CONST_CALL_P (insns) = 1;
+
+             if (GET_MODE (x) != Pmode)
+               x = gen_rtx_ZERO_EXTEND (Pmode, x);
+
              emit_libcall_block (insns, dest, rax, x);
            }
          else
@@ -12842,11 +12850,12 @@

          if (TARGET_64BIT)
            {
-             rtx rax = gen_rtx_REG (Pmode, AX_REG), insns, eqv;
+             rtx rax = gen_rtx_REG (Pmode, AX_REG);
+             rtx insns, eqv;

              start_sequence ();
-             emit_call_insn (ix86_gen_tls_local_dynamic_base_64 (rax,
-                                                                 caddr));
+             emit_call_insn
+               (ix86_gen_tls_local_dynamic_base_64 (rax, caddr));
              insns = get_insns ();
              end_sequence ();

@@ -12871,6 +12880,9 @@
        {
          dest = force_reg (Pmode, gen_rtx_PLUS (Pmode, dest, tp));

+         if (GET_MODE (x) != Pmode)
+           x = gen_rtx_ZERO_EXTEND (Pmode, x);
+
          set_unique_reg_note (get_last_insn (), REG_EQUAL, x);
        }
       break;
--cut here--