From patchwork Thu Oct  7 12:49:11 2010
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Subject: [RS6000] PR 45807 r2 eh_frame info error
From: Alan Modra <amodra@gmail.com>
X-Patchwork-Id: 67049
Message-Id: <20101007124911.GF29181@bubble.grove.modra.org>
To: Richard Henderson <rth@redhat.com>
Cc: gcc-patches@gcc.gnu.org, David Edelsohn <dje.gcc@gmail.com>
Date: Thu, 7 Oct 2010 23:19:11 +1030

On Fri, Oct 01, 2010 at 10:15:19AM -0700, Richard Henderson wrote:
> Better, maybe, to use gen_int_mode here instead of the
> explicit sign-extension trick.

I did consider that when writing the original patch, and decided it
was hardly necessary for a simple constant.  After all, I knew the
integer promotion rules and how to do sign extension.  Turned out of
course that didn't mean I could write flawless code..

David said this morning he'd rather gen_int_mode for maintainability,
even if the code is now correct, so here goes.  Committed r165101.

	* config/rs6000/rs6000.c (rs6000_emit_prologue): Use gen_int_mode
	rather than sign extension by hand.


Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c	(revision 165080)
+++ gcc/config/rs6000/rs6000.c	(working copy)
@@ -20214,7 +20214,7 @@ rs6000_emit_prologue (void)
   /* In AIX ABI we need to make sure r2 is really saved.  */
   if (TARGET_AIX && crtl->calls_eh_return)
     {
-      rtx tmp_reg, tmp_reg_si, compare_result, toc_save_done, jump;
+      rtx tmp_reg, tmp_reg_si, hi, lo, compare_result, toc_save_done, jump;
       long toc_restore_insn;
 
       gcc_assert (frame_reg_rtx == frame_ptr_rtx
@@ -20232,15 +20232,13 @@ rs6000_emit_prologue (void)
 	 toc adjusting stub.  */
       emit_move_insn (tmp_reg_si, gen_rtx_MEM (SImode, tmp_reg));
       toc_restore_insn = TARGET_32BIT ? 0x80410014 : 0xE8410028;
-      toc_restore_insn = (toc_restore_insn ^ 0x80000000) - 0x80000000;
-      emit_insn (gen_xorsi3 (tmp_reg_si, tmp_reg_si,
-			     GEN_INT (toc_restore_insn & ~0xffff)));
+      hi = gen_int_mode (toc_restore_insn & ~0xffff, SImode);
+      emit_insn (gen_xorsi3 (tmp_reg_si, tmp_reg_si, hi));
       compare_result = gen_rtx_REG (CCUNSmode, CR0_REGNO);
       validate_condition_mode (EQ, CCUNSmode);
+      lo = gen_int_mode (toc_restore_insn & 0xffff, SImode);
       emit_insn (gen_rtx_SET (VOIDmode, compare_result,
-			      gen_rtx_COMPARE (CCUNSmode, tmp_reg_si,
-					       GEN_INT (toc_restore_insn
-							& 0xffff))));
+			      gen_rtx_COMPARE (CCUNSmode, tmp_reg_si, lo)));
       toc_save_done = gen_label_rtx ();
       jump = gen_rtx_IF_THEN_ELSE (VOIDmode,
 				   gen_rtx_EQ (VOIDmode, compare_result,