[PATCH, 3/10] skip swapping operands used in ccmp

[Zhenqiang Chen]

Hi,

Swapping operands in a ccmp will lead to illegal instructions. So the
patch disables it in simplify_while_replacing.

The patch is separated from
https://gcc.gnu.org/ml/gcc-patches/2014-02/msg01407.html.

To make it clean. The patch adds two files: ccmp.{c,h} to hold all new
ccmp related functions.

OK for trunk?

Thanks!
-Zhenqiang

ChangeLog:
2014-06-23  Zhenqiang Chen  <zhenqiang.chen@linaro.org>

        * Makefile.in: Add ccmp.o
        * ccmp.c: New file.
        * ccmp.h: New file.
        * recog.c (simplify_while_replacing): Check ccmp_insn_p.

diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 5587b75..8757a30 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -1169,6 +1169,7 @@ OBJS = \
        builtins.o \
        caller-save.o \
        calls.o \
+       ccmp.o \
        cfg.o \
        cfganal.o \
        cfgbuild.o \
diff --git a/gcc/ccmp.c b/gcc/ccmp.c
new file mode 100644
index 0000000..665c2a5
--- /dev/null
+++ b/gcc/ccmp.c
@@ -0,0 +1,62 @@
+/* Conditional compare related functions
+   Copyright (C) 2014-2014 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "rtl.h"
+#include "tree.h"
+#include "stringpool.h"
+#include "regs.h"
+#include "expr.h"
+#include "optabs.h"
+#include "tree-iterator.h"
+#include "basic-block.h"
+#include "tree-ssa-alias.h"
+#include "internal-fn.h"
+#include "gimple-expr.h"
+#include "is-a.h"
+#include "gimple.h"
+#include "gimple-ssa.h"
+#include "tree-ssanames.h"
+#include "target.h"
+#include "common/common-target.h"
+#include "df.h"
+#include "tree-ssa-live.h"
+#include "tree-outof-ssa.h"
+#include "cfgexpand.h"
+#include "tree-phinodes.h"
+#include "ssa-iterators.h"
+#include "expmed.h"
+#include "ccmp.h"
+
+bool
+ccmp_insn_p (rtx object)
+{
+  rtx x = PATTERN (object);
+  if (targetm.gen_ccmp_first
+      && GET_CODE (x) == SET
+      && GET_CODE (XEXP (x, 1)) == COMPARE
+      && (GET_CODE (XEXP (XEXP (x, 1), 0)) == IOR
+         || GET_CODE (XEXP (XEXP (x, 1), 0)) == AND))
+    return true;
+  return false;
+}
+
diff --git a/gcc/ccmp.h b/gcc/ccmp.h
new file mode 100644
index 0000000..7e139aa
--- /dev/null
+++ b/gcc/ccmp.h
@@ -0,0 +1,25 @@
+/* Conditional comapre related functions.
+   Copyright (C) 2014-2014 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.:
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_CCMP_H
+#define GCC_CCMP_H
+
+extern bool ccmp_insn_p (rtx);
+
+#endif  /* GCC_CCMP_H  */
diff --git a/gcc/recog.c b/gcc/recog.c
index 8d10a4f..b53a28c 100644
--- a/gcc/recog.c
+++ b/gcc/recog.c
@@ -40,6 +40,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-pass.h"
 #include "df.h"
 #include "insn-codes.h"
+#include "ccmp.h"

 #ifndef STACK_PUSH_CODE
 #ifdef STACK_GROWS_DOWNWARD
@@ -577,7 +578,8 @@ simplify_while_replacing (rtx *loc, rtx to, rtx object,
   enum rtx_code code = GET_CODE (x);
   rtx new_rtx = NULL_RTX;

-  if (SWAPPABLE_OPERANDS_P (x)
+  /* Do not swap compares in conditional compare instruction.  */
+  if (SWAPPABLE_OPERANDS_P (x) && !ccmp_insn_p (object)
       && swap_commutative_operands_p (XEXP (x, 0), XEXP (x, 1)))
     {
       validate_unshare_change (object, loc,