Re: [0/7] Type promotion pass and elimination of zext/sext

[Kugan <kugan.vivekanandarajah@linaro.org>]

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Attached is the latest version of the patch. With the patches
0001-Add-new-SEXT_EXPR-tree-code.patch,
0002-Add-type-promotion-pass.patch and
0003-Optimize-ZEXT_EXPR-with-tree-vrp.patch.

I did bootstrap on ppc64-linux-gnu, aarch64-linux-gnu and
x64-64-linux-gnu and regression testing on ppc64-linux-gnu,
aarch64-linux-gnu arm64-linux-gnu and x64-64-linux-gnu. I ran into three
issues in ppc64-linux-gnu regression testing. There are some other test
cases which needs adjustment for scanning for some patterns that are not
valid now.

1. rtl fwprop was going into infinite loop. Works with the following patch:
diff --git a/gcc/fwprop.c b/gcc/fwprop.c
index 16c7981..9cf4f43 100644
--- a/gcc/fwprop.c
+++ b/gcc/fwprop.c
@@ -948,6 +948,10 @@ try_fwprop_subst (df_ref use, rtx *loc, rtx
new_rtx, rtx_insn *def_insn,
   int old_cost = 0;
   bool ok;

+  /* Value to be substituted is the same, nothing to do.  */
+  if (rtx_equal_p (*loc, new_rtx))
+    return false;
+
   update_df_init (def_insn, insn);

   /* forward_propagate_subreg may be operating on an instruction with

2. gcc.dg/torture/ftrapv-1.c fails
This is because we are checking for the  SImode trapping. With the
promotion of the operation to wider mode, this is i think expected. I
think the testcase needs updating.
3. gcc.dg/sms-3.c fails
It fails with  -fmodulo-sched-allow-regmoves  and OK when I remove it. I
am looking into it.


I also have the following issues based on the previous review (as posted
in the previous patch). Copying again for the review purpose.

1.
> you still call promote_ssa on both DEFs and USEs and promote_ssa looks
> at SSA_NAME_DEF_STMT of the passed arg.  Please call promote_ssa just
> on DEFs and fixup_uses on USEs.

I am doing this to promote SSA that are defined with GIMPLE_NOP. Is
there anyway to iterate over this. I have added gcc_assert to make sure
that promote_ssa is called only once.

2.
> Instead of this you should, in promote_all_stmts, walk over all uses
doing what
> fixup_uses does and then walk over all defs, doing what promote_ssa does.
>
> +    case GIMPLE_NOP:
> +       {
> +         if (SSA_NAME_VAR (def) == NULL)
> +           {
> +             /* Promote def by fixing its type for anonymous def.  */
> +             TREE_TYPE (def) = promoted_type;
> +           }
> +         else
> +           {
> +             /* Create a promoted copy of parameters.  */
> +             bb = single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun));
>
> I think the uninitialized vars are somewhat tricky and it would be best
> to create a new uninit anonymous SSA name for them.  You can
> have SSA_NAME_VAR != NULL and def _not_ being a parameter
> btw.

I experimented with get_or_create_default_def. Here  we have to have a
SSA_NAME_VAR (def) of promoted type.

In the attached patch I am doing the following and seems to work. Does
this looks OK?

+	  }
+	else if (TREE_CODE (SSA_NAME_VAR (def)) != PARM_DECL)
+	  {
+	    tree var = copy_node (SSA_NAME_VAR (def));
+	    TREE_TYPE (var) = promoted_type;
+	    TREE_TYPE (def) = promoted_type;
+	    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, var);
+	  }

I prefer to promote def as otherwise iterating over the uses and
promoting can look complicated (have to look at all the different types
of stmts again and do the right thing as It was in the earlier version
of this before we move to this approach)

3)
> you can also transparently handle constants for the cases where promoting
> is required.  At the moment their handling is interwinded with the def
promotion
> code.  That makes the whole thing hard to follow.


I have updated the comments with:

+/* Promote constants in STMT to TYPE.  If PROMOTE_COND_EXPR is true,
+   promote only the constants in conditions part of the COND_EXPR.
+
+   We promote the constants when the associated operands are promoted.
+   This usually means that we promote the constants when we promote the
+   defining stmnts (as part of promote_ssa). However for COND_EXPR, we
+   can promote only when we promote the other operand. Therefore, this
+   is done during fixup_use.  */


4)
I am handling gimple_debug separately to avoid any code difference with
and without -g option. I have updated the comments for this.

5)
I also noticed that tree-ssa-uninit sometimes gives false positives due
to the assumptions
it makes. Is it OK to move this pass before type promotion? I can do the
testings and post a separate patch with this if this OK.

6)
I also removed the optimization that prevents some of the redundant
truncation/extensions from type promotion pass, as it dosent do much as
of now. I can send a proper follow up patch. Is that OK?

I also did a simple test with coremark for the latest patch. I compared
the code size for coremark for linux-gcc with -Os. Results are as
reported by the "size" utility. I know this doesn't mean much but can
give some indication.
	Base   		with pass	Percentage improvement
==============================================================
arm	10476		10372		0.9927453226
aarch64	9545		9521		0.2514405448
ppc64	12236		12052		1.5037593985


After resolving the above issues, I would like propose that we  commit
the pass as not enabled by default (even though the patch as it stands
enabled by default - I am doing it for testing purposes).

Thanks,
Kugan



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From 8e71ea17eaf6f282325076f588dbdf4f53c8b865 Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandarajah@linaro.org>
Date: Thu, 22 Oct 2015 10:53:56 +1100
Subject: [PATCH 3/5] Optimize ZEXT_EXPR with tree-vrp

---
 gcc/match.pd   |  6 ++++++
 gcc/tree-vrp.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/gcc/match.pd b/gcc/match.pd
index 0a9598e..1b152f1 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -2585,3 +2585,9 @@ along with GCC; see the file COPYING3.  If not see
   (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)))
    (op @0 (ext @1 @2)))))
 
+(simplify
+ (sext (sext@2 @0 @1) @3)
+ (if (tree_int_cst_compare (@1, @3) <= 0)
+  @2
+  (sext @0 @3)))
+
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index fe34ffd..024c8ef 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -2241,6 +2241,7 @@ extract_range_from_binary_expr_1 (value_range *vr,
       && code != LSHIFT_EXPR
       && code != MIN_EXPR
       && code != MAX_EXPR
+      && code != SEXT_EXPR
       && code != BIT_AND_EXPR
       && code != BIT_IOR_EXPR
       && code != BIT_XOR_EXPR)
@@ -2801,6 +2802,54 @@ extract_range_from_binary_expr_1 (value_range *vr,
       extract_range_from_multiplicative_op_1 (vr, code, &vr0, &vr1);
       return;
     }
+  else if (code == SEXT_EXPR)
+    {
+      gcc_assert (range_int_cst_p (&vr1));
+      HOST_WIDE_INT prec = tree_to_uhwi (vr1.min);
+      type = vr0.type;
+      wide_int tmin, tmax;
+      wide_int may_be_nonzero, must_be_nonzero;
+
+      wide_int type_min = wi::min_value (prec, SIGNED);
+      wide_int type_max = wi::max_value (prec, SIGNED);
+      type_min = wide_int_to_tree (expr_type, type_min);
+      type_max = wide_int_to_tree (expr_type, type_max);
+      type_min = wi::sext (type_min, prec);
+      type_max = wi::sext (type_max, prec);
+      wide_int sign_bit
+	= wi::set_bit_in_zero (prec - 1,
+			       TYPE_PRECISION (TREE_TYPE (vr0.min)));
+      if (zero_nonzero_bits_from_vr (expr_type, &vr0,
+				     &may_be_nonzero,
+				     &must_be_nonzero))
+	{
+	  if (wi::bit_and (must_be_nonzero, sign_bit) == sign_bit)
+	    {
+	      /* If to-be-extended sign bit is one.  */
+	      tmin = type_min;
+	      tmax = wi::zext (may_be_nonzero, prec);
+	    }
+	  else if (wi::bit_and (may_be_nonzero, sign_bit)
+		   != sign_bit)
+	    {
+	      /* If to-be-extended sign bit is zero.  */
+	      tmin = wi::zext (must_be_nonzero, prec);
+	      tmax = wi::zext (may_be_nonzero, prec);
+	    }
+	  else
+	    {
+	      tmin = type_min;
+	      tmax = type_max;
+	    }
+	}
+      else
+	{
+	  tmin = type_min;
+	  tmax = type_max;
+	}
+      min = wide_int_to_tree (expr_type, tmin);
+      max = wide_int_to_tree (expr_type, tmax);
+    }
   else if (code == RSHIFT_EXPR
 	   || code == LSHIFT_EXPR)
     {
@@ -9166,6 +9215,17 @@ simplify_bit_ops_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt)
 	  break;
 	}
       break;
+    case SEXT_EXPR:
+	{
+	  unsigned int prec = tree_to_uhwi (op1);
+	  wide_int min = vr0.min;
+	  wide_int max = vr0.max;
+	  wide_int sext_min = wi::sext (min, prec);
+	  wide_int sext_max = wi::sext (max, prec);
+	  if (min == sext_min && max == sext_max)
+	    op = op0;
+	}
+      break;
     default:
       gcc_unreachable ();
     }
@@ -9868,6 +9928,7 @@ simplify_stmt_using_ranges (gimple_stmt_iterator *gsi)
 
 	case BIT_AND_EXPR:
 	case BIT_IOR_EXPR:
+	case SEXT_EXPR:
 	  /* Optimize away BIT_AND_EXPR and BIT_IOR_EXPR
 	     if all the bits being cleared are already cleared or
 	     all the bits being set are already set.  */
-- 
1.9.1


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From 42128668393c32c3860d346ead7b3118a090ffa4 Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandarajah@linaro.org>
Date: Thu, 22 Oct 2015 10:52:37 +1100
Subject: [PATCH 2/5] Add type promotion pass

---
 gcc/Makefile.in               |   1 +
 gcc/auto-profile.c            |   2 +-
 gcc/common.opt                |   4 +
 gcc/doc/invoke.texi           |  10 +
 gcc/gimple-ssa-type-promote.c | 867 ++++++++++++++++++++++++++++++++++++++++++
 gcc/passes.def                |   1 +
 gcc/timevar.def               |   1 +
 gcc/tree-pass.h               |   1 +
 libiberty/cp-demangle.c       |   2 +-
 9 files changed, 887 insertions(+), 2 deletions(-)
 create mode 100644 gcc/gimple-ssa-type-promote.c

diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index b91b8dc..c6aed45 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -1499,6 +1499,7 @@ OBJS = \
 	tree-vect-slp.o \
 	tree-vectorizer.o \
 	tree-vrp.o \
+	gimple-ssa-type-promote.o \
 	tree.o \
 	valtrack.o \
 	value-prof.o \
diff --git a/gcc/auto-profile.c b/gcc/auto-profile.c
index 25202c5..d32c3b6 100644
--- a/gcc/auto-profile.c
+++ b/gcc/auto-profile.c
@@ -1266,7 +1266,7 @@ afdo_propagate_circuit (const bb_set &annotated_bb, edge_set *annotated_edge)
     FOR_EACH_EDGE (e, ei, bb->succs)
     {
       unsigned i, total = 0;
-      edge only_one;
+      edge only_one = NULL;
       bool check_value_one = (((integer_onep (cmp_rhs))
                                ^ (gimple_cond_code (cmp_stmt) == EQ_EXPR))
                               ^ ((e->flags & EDGE_TRUE_VALUE) != 0));
diff --git a/gcc/common.opt b/gcc/common.opt
index 12ca0d6..f450428 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -2404,6 +2404,10 @@ ftree-vrp
 Common Report Var(flag_tree_vrp) Init(0) Optimization
 Perform Value Range Propagation on trees.
 
+ftree-type-promote
+Common Report Var(flag_tree_type_promote) Init(1) Optimization
+Perform Type Promotion on trees
+
 funit-at-a-time
 Common Report Var(flag_unit_at_a_time) Init(1)
 Compile whole compilation unit at a time.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index cd82544..bc059a0 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -9093,6 +9093,16 @@ enabled by default at @option{-O2} and higher.  Null pointer check
 elimination is only done if @option{-fdelete-null-pointer-checks} is
 enabled.
 
+@item -ftree-type-promote
+@opindex ftree-type-promote
+This pass applies type promotion to SSA names in the function and
+inserts appropriate truncations to preserve the semantics.  Idea of
+this pass is to promote operations such a way that we can minimise
+generation of subreg in RTL, that intern results in removal of
+redundant zero/sign extensions.
+
+This optimization is enabled by default.
+
 @item -fsplit-ivs-in-unroller
 @opindex fsplit-ivs-in-unroller
 Enables expression of values of induction variables in later iterations
diff --git a/gcc/gimple-ssa-type-promote.c b/gcc/gimple-ssa-type-promote.c
new file mode 100644
index 0000000..735e7ee
--- /dev/null
+++ b/gcc/gimple-ssa-type-promote.c
@@ -0,0 +1,867 @@
+/* Type promotion of SSA names to minimise redundant zero/sign extension.
+   Copyright (C) 2015 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 "backend.h"
+#include "hash-set.h"
+#include "machmode.h"
+#include "vec.h"
+#include "double-int.h"
+#include "input.h"
+#include "symtab.h"
+#include "wide-int.h"
+#include "inchash.h"
+#include "tree.h"
+#include "fold-const.h"
+#include "stor-layout.h"
+#include "predict.h"
+#include "function.h"
+#include "dominance.h"
+#include "cfg.h"
+#include "basic-block.h"
+#include "tree-ssa-alias.h"
+#include "gimple-fold.h"
+#include "tree-eh.h"
+#include "gimple-expr.h"
+#include "is-a.h"
+#include "gimple.h"
+#include "gimple-iterator.h"
+#include "gimple-ssa.h"
+#include "tree-phinodes.h"
+#include "ssa-iterators.h"
+#include "stringpool.h"
+#include "tree-ssanames.h"
+#include "tree-pass.h"
+#include "gimple-pretty-print.h"
+#include "langhooks.h"
+#include "sbitmap.h"
+#include "domwalk.h"
+#include "tree-dfa.h"
+
+/* This pass applies type promotion to SSA names in the function and
+   inserts appropriate truncations.  Idea of this pass is to promote operations
+   such a way that we can minimise generation of subreg in RTL,
+   that in turn results in removal of redundant zero/sign extensions.  This pass
+   will run prior to The VRP and DOM such that they will be able to optimise
+   redundant truncations and extensions.  This is based on the discussion from
+   https://gcc.gnu.org/ml/gcc-patches/2014-09/msg00472.html.
+*/
+
+/* Structure to hold the type and promoted type for promoted ssa variables.  */
+struct ssa_name_info
+{
+  tree ssa;		/* Name of the SSA_NAME.  */
+  tree type;		/* Original type of ssa.  */
+  tree promoted_type;	/* Promoted type of ssa.  */
+};
+
+/* Obstack for ssa_name_info.  */
+static struct obstack ssa_name_info_obstack;
+
+static unsigned n_ssa_val;
+static sbitmap ssa_to_be_promoted_bitmap;
+static hash_map <tree, ssa_name_info *>  *ssa_name_info_map;
+
+static bool
+type_precision_ok (tree type)
+{
+  return (TYPE_PRECISION (type)
+	  == GET_MODE_PRECISION (TYPE_MODE (type)));
+}
+
+/* Return the promoted type for TYPE.  */
+static tree
+get_promoted_type (tree type)
+{
+  tree promoted_type;
+  enum machine_mode mode;
+  int uns;
+
+  if (POINTER_TYPE_P (type)
+      || !INTEGRAL_TYPE_P (type)
+      || !type_precision_ok (type))
+    return type;
+
+  mode = TYPE_MODE (type);
+#ifdef PROMOTE_MODE
+  uns = TYPE_SIGN (type);
+  PROMOTE_MODE (mode, uns, type);
+#endif
+  uns = TYPE_SIGN (type);
+  if (TYPE_PRECISION (type) == GET_MODE_PRECISION (mode))
+    return type;
+  promoted_type
+    = build_nonstandard_integer_type (GET_MODE_PRECISION (mode),
+				      uns);
+  gcc_assert (TYPE_PRECISION (promoted_type) == GET_MODE_PRECISION (mode));
+  return promoted_type;
+}
+
+/* Return true if ssa NAME is already considered for promotion.  */
+static bool
+ssa_promoted_p (tree name)
+{
+  if (TREE_CODE (name) == SSA_NAME)
+    {
+      unsigned int index = SSA_NAME_VERSION (name);
+      if (index < n_ssa_val)
+	return bitmap_bit_p (ssa_to_be_promoted_bitmap, index);
+    }
+  return true;
+}
+
+/* Set ssa NAME to be already considered for promotion.  */
+static void
+set_ssa_promoted (tree name)
+{
+  if (TREE_CODE (name) == SSA_NAME)
+    {
+      unsigned int index = SSA_NAME_VERSION (name);
+      if (index < n_ssa_val)
+	bitmap_set_bit (ssa_to_be_promoted_bitmap, index);
+    }
+}
+
+/* Return true if LHS will be promoted later.  */
+static bool
+tobe_promoted_p (tree lhs)
+{
+  if (TREE_CODE (lhs) == SSA_NAME
+      && !POINTER_TYPE_P (TREE_TYPE (lhs))
+      && INTEGRAL_TYPE_P (TREE_TYPE (lhs))
+      && !VECTOR_TYPE_P (TREE_TYPE (lhs))
+      && !ssa_promoted_p (lhs)
+      && (get_promoted_type (TREE_TYPE (lhs))
+	  != TREE_TYPE (lhs)))
+    return true;
+  else
+    return false;
+}
+
+/* Return true if the tree CODE needs the propmoted operand to be
+   truncated (when stray bits are set beyond the original type in
+   promoted mode) to preserve the semantics.  */
+static bool
+truncate_use_p (enum tree_code code)
+{
+  if (code == TRUNC_DIV_EXPR
+      || code == CEIL_DIV_EXPR
+      || code == FLOOR_DIV_EXPR
+      || code == ROUND_DIV_EXPR
+      || code == TRUNC_MOD_EXPR
+      || code == CEIL_MOD_EXPR
+      || code == FLOOR_MOD_EXPR
+      || code == ROUND_MOD_EXPR
+      || code == LSHIFT_EXPR
+      || code == RSHIFT_EXPR
+      || code == MAX_EXPR
+      || code == MIN_EXPR)
+    return true;
+  else
+    return false;
+}
+
+/* Convert constant CST to TYPE.  */
+static tree
+convert_int_cst (tree type, tree cst, signop sign = SIGNED)
+{
+  wide_int wi_cons = fold_convert (type, cst);
+  wi_cons = wi::ext (wi_cons, TYPE_PRECISION (TREE_TYPE (cst)), sign);
+  return wide_int_to_tree (type, wi_cons);
+}
+
+/* Promote constants in STMT to TYPE.  If PROMOTE_COND_EXPR is true,
+   promote only the constants in conditions part of the COND_EXPR.
+
+   We promote the constants when the associated operands are promoted.
+   This usually means that we promote the constants when we promote the
+   defining stmnts (as part of promote_ssa). However for COND_EXPR, we
+   can promote only when we promote the other operand. Therefore, this
+   is done during fixup_use.  */
+
+static void
+promote_cst_in_stmt (gimple *stmt, tree type, bool promote_cond = false)
+{
+  tree op;
+  ssa_op_iter iter;
+  use_operand_p oprnd;
+  int index;
+  tree op0, op1;
+  signop sign = SIGNED;
+
+  switch (gimple_code (stmt))
+    {
+    case GIMPLE_ASSIGN:
+      if (promote_cond
+	  && gimple_assign_rhs_code (stmt) == COND_EXPR)
+	{
+	  /* Promote INTEGER_CST that are tcc_compare arguments.  */
+	  sign = TYPE_SIGN (type);
+	  op = gimple_assign_rhs1 (stmt);
+	  op0 = TREE_OPERAND (op, 0);
+	  op1 = TREE_OPERAND (op, 1);
+	  if (TREE_CODE (op0) == INTEGER_CST)
+	    op0 = convert_int_cst (type, op0, sign);
+	  if (TREE_CODE (op1) == INTEGER_CST)
+	    op1 = convert_int_cst (type, op1, sign);
+	  tree new_op = build2 (TREE_CODE (op), type, op0, op1);
+	  gimple_assign_set_rhs1 (stmt, new_op);
+	}
+      else
+	{
+	  /* Promote INTEGER_CST in GIMPLE_ASSIGN.  */
+	  op = gimple_assign_rhs3 (stmt);
+	  if (op && TREE_CODE (op) == INTEGER_CST)
+	    gimple_assign_set_rhs3 (stmt, convert_int_cst (type, op, sign));
+	  if ((TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))
+	       == tcc_comparison)
+	      || truncate_use_p (gimple_assign_rhs_code (stmt)))
+	    sign = TYPE_SIGN (type);
+	  op = gimple_assign_rhs1 (stmt);
+	  if (op && TREE_CODE (op) == INTEGER_CST)
+	    gimple_assign_set_rhs1 (stmt, convert_int_cst (type, op, sign));
+	  op = gimple_assign_rhs2 (stmt);
+	  if (op && TREE_CODE (op) == INTEGER_CST)
+	    gimple_assign_set_rhs2 (stmt, convert_int_cst (type, op, sign));
+	}
+      break;
+
+    case GIMPLE_PHI:
+	{
+	  /* Promote INTEGER_CST arguments to GIMPLE_PHI.  */
+	  gphi *phi = as_a <gphi *> (stmt);
+	  FOR_EACH_PHI_ARG (oprnd, phi, iter, SSA_OP_USE)
+	    {
+	      op = USE_FROM_PTR (oprnd);
+	      index = PHI_ARG_INDEX_FROM_USE (oprnd);
+	      if (TREE_CODE (op) == INTEGER_CST)
+		SET_PHI_ARG_DEF (phi, index, convert_int_cst (type, op, sign));
+	    }
+	}
+      break;
+
+    case GIMPLE_COND:
+	{
+	  /* Promote INTEGER_CST that are GIMPLE_COND arguments.  */
+	  gcond *cond = as_a <gcond *> (stmt);
+	  sign = TYPE_SIGN (type);
+	  op = gimple_cond_lhs (cond);
+	  if (op && TREE_CODE (op) == INTEGER_CST)
+	    gimple_cond_set_lhs (cond, convert_int_cst (type, op, sign));
+
+	  op = gimple_cond_rhs (cond);
+	  if (op && TREE_CODE (op) == INTEGER_CST)
+	    gimple_cond_set_rhs (cond, convert_int_cst (type, op, sign));
+	}
+      break;
+
+    default:
+      gcc_unreachable ();
+    }
+}
+
+/* Create an ssa with TYPE to copy ssa VAR.  */
+static tree
+make_promoted_copy (tree var, gimple *def_stmt, tree type)
+{
+  tree new_lhs = make_ssa_name (type, def_stmt);
+  if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (var))
+    SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_lhs) = 1;
+  return new_lhs;
+}
+
+/* Zero/sign extend (depending on UNSIGNED_P) VAR and truncate to WIDTH bits.
+   Assign the zero/sign extended value in NEW_VAR.  gimple statement
+   that performs the zero/sign extension is returned.  */
+static gimple *
+zero_sign_extend_stmt (tree new_var, tree var, bool unsigned_p, int width)
+{
+  gcc_assert (TYPE_PRECISION (TREE_TYPE (var))
+	      == TYPE_PRECISION (TREE_TYPE (new_var)));
+  gcc_assert (TYPE_PRECISION (TREE_TYPE (var)) > width);
+  gimple *stmt;
+
+  if (unsigned_p)
+    {
+      /* Zero extend.  */
+      tree cst
+	= wide_int_to_tree (TREE_TYPE (var),
+			    wi::mask (width, false,
+				      TYPE_PRECISION (TREE_TYPE (var))));
+      stmt = gimple_build_assign (new_var, BIT_AND_EXPR,
+				  var, cst);
+    }
+  else
+    /* Sign extend.  */
+    stmt = gimple_build_assign (new_var,
+				SEXT_EXPR,
+				var, build_int_cst (TREE_TYPE (var), width));
+  return stmt;
+}
+
+
+static void
+copy_default_ssa (tree to, tree from)
+{
+  SET_SSA_NAME_VAR_OR_IDENTIFIER (to, SSA_NAME_VAR (from));
+  SSA_NAME_DEF_STMT (to) = SSA_NAME_DEF_STMT (from);
+  SET_SSA_NAME_VAR_OR_IDENTIFIER (from, NULL_TREE);
+  SSA_NAME_IS_DEFAULT_DEF (to) = 1;
+  SSA_NAME_IS_DEFAULT_DEF (from) = 0;
+}
+
+/* Promote definition DEF to PROMOTED_TYPE.  If the stmt that defines def
+   is def_stmt, make the type of def promoted_type.  If the stmt is such
+   that, result of the def_stmt cannot be of promoted_type, create a new_def
+   of the original_type and make the def_stmt assign its value to newdef.
+   Then, create a NOP_EXPR to convert new_def to def of promoted type.
+
+   For example, for stmt with original_type char and promoted_type int:
+		char _1 = mem;
+	becomes:
+		char _2 = mem;
+		int _1 = (int)_2;
+
+   If the def_stmt allows def to be promoted, promote def in-place
+   (and its arguments when needed).
+
+   For example:
+		char _3 = _1 + _2;
+	becomes:
+		int _3 = _1 + _2;
+   Here, _1 and _2 will also be promoted.  */
+
+static void
+promote_ssa (tree def, gimple_stmt_iterator *gsi)
+{
+  gimple *def_stmt = SSA_NAME_DEF_STMT (def);
+  gimple *copy_stmt = NULL;
+  basic_block bb;
+  gimple_stmt_iterator gsi2;
+  tree original_type = TREE_TYPE (def);
+  tree new_def;
+  ssa_name_info *info;
+  bool do_not_promote = false;
+  tree promoted_type = get_promoted_type (TREE_TYPE (def));
+
+  if (!tobe_promoted_p (def))
+    return;
+
+  info = (ssa_name_info *) obstack_alloc (&ssa_name_info_obstack,
+							 sizeof (ssa_name_info));
+  info->type = original_type;
+  info->promoted_type = promoted_type;
+  info->ssa = def;
+  gcc_assert (!ssa_name_info_map->get_or_insert (def));
+  ssa_name_info_map->put (def, info);
+
+  switch (gimple_code (def_stmt))
+    {
+    case GIMPLE_PHI:
+      {
+	/* Promote def by fixing its type and make def anonymous.  */
+	TREE_TYPE (def) = promoted_type;
+	SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+	promote_cst_in_stmt (def_stmt, promoted_type);
+	break;
+      }
+
+    case GIMPLE_ASM:
+      {
+	gasm *asm_stmt = as_a <gasm *> (def_stmt);
+	for (unsigned int i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
+	  {
+	    /* Promote def and copy (i.e. convert) the value defined
+	       by asm to def.  */
+	    tree link = gimple_asm_output_op (asm_stmt, i);
+	    tree op = TREE_VALUE (link);
+	    if (op == def)
+	      {
+		new_def = copy_ssa_name (def);
+		set_ssa_promoted (new_def);
+		copy_default_ssa (new_def, def);
+		TREE_VALUE (link) = new_def;
+		gimple_asm_set_output_op (asm_stmt, i, link);
+
+		TREE_TYPE (def) = promoted_type;
+		copy_stmt = gimple_build_assign (def, NOP_EXPR,
+						 new_def, NULL_TREE);
+		SSA_NAME_IS_DEFAULT_DEF (new_def) = 0;
+		gsi2 = gsi_for_stmt (def_stmt);
+		gsi_insert_after (&gsi2, copy_stmt, GSI_NEW_STMT);
+		break;
+	      }
+	  }
+	break;
+      }
+
+    case GIMPLE_NOP:
+      {
+	if (SSA_NAME_VAR (def) == NULL)
+	  {
+	    /* Promote def by fixing its type for anonymous def.  */
+	    TREE_TYPE (def) = promoted_type;
+	  }
+	else if (TREE_CODE (SSA_NAME_VAR (def)) != PARM_DECL)
+	  {
+	    tree var = copy_node (SSA_NAME_VAR (def));
+	    TREE_TYPE (var) = promoted_type;
+	    TREE_TYPE (def) = promoted_type;
+	    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, var);
+	  }
+	else
+	  {
+	    /* Create a promoted copy of parameters.  */
+	    bb = single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun));
+	    gcc_assert (bb);
+	    gsi2 = gsi_after_labels (bb);
+	    /* Create new_def of the original type and set that to be the
+	       parameter.  */
+	    new_def = copy_ssa_name (def);
+	    set_ssa_promoted (new_def);
+	    set_ssa_default_def (cfun, SSA_NAME_VAR (def), new_def);
+	    copy_default_ssa (new_def, def);
+
+	    /* Now promote the def and copy the value from parameter.  */
+	    TREE_TYPE (def) = promoted_type;
+	    copy_stmt = gimple_build_assign (def, NOP_EXPR,
+					     new_def, NULL_TREE);
+	    SSA_NAME_DEF_STMT (def) = copy_stmt;
+	    gsi_insert_before (&gsi2, copy_stmt, GSI_NEW_STMT);
+	  }
+	break;
+      }
+
+    case GIMPLE_ASSIGN:
+      {
+	enum tree_code code = gimple_assign_rhs_code (def_stmt);
+	tree rhs = gimple_assign_rhs1 (def_stmt);
+	if (gimple_vuse (def_stmt) != NULL_TREE
+	    || gimple_vdef (def_stmt) != NULL_TREE
+	    || TREE_CODE_CLASS (code) == tcc_reference
+	    || code == LROTATE_EXPR
+	    || code == RROTATE_EXPR
+	    || code == VIEW_CONVERT_EXPR
+	    || code == REALPART_EXPR
+	    || code == IMAGPART_EXPR
+	    || code == REDUC_PLUS_EXPR
+	    || code == REDUC_MAX_EXPR
+	    || code == REDUC_MIN_EXPR
+	    || !INTEGRAL_TYPE_P (TREE_TYPE (rhs)))
+	  {
+	    do_not_promote = true;
+	  }
+	else if (CONVERT_EXPR_CODE_P (code))
+	  {
+	    if (!type_precision_ok (TREE_TYPE (rhs)))
+	      {
+		do_not_promote = true;
+	      }
+	    else if (types_compatible_p (TREE_TYPE (rhs), promoted_type))
+	      {
+		/* As we travel statements in dominated order, arguments
+		   of def_stmt will be visited before visiting def.  If RHS
+		   is already promoted and type is compatible, we can convert
+		   them into ZERO/SIGN EXTEND stmt.  */
+		ssa_name_info *info = ssa_name_info_map->get_or_insert (rhs);
+		tree type;
+		if (info == NULL)
+		  type = TREE_TYPE (rhs);
+		else
+		  type = info->type;
+		if ((TYPE_PRECISION (original_type)
+		     > TYPE_PRECISION (type))
+		    || (TYPE_UNSIGNED (original_type)
+			!= TYPE_UNSIGNED (type)))
+		  {
+		    if (TYPE_PRECISION (original_type) < TYPE_PRECISION (type))
+		      type = original_type;
+		    gcc_assert (type != NULL_TREE);
+		    TREE_TYPE (def) = promoted_type;
+		    gimple *copy_stmt =
+		      zero_sign_extend_stmt (def, rhs,
+					     TYPE_UNSIGNED (type),
+					     TYPE_PRECISION (type));
+		    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+		    gsi_replace (gsi, copy_stmt, false);
+		  }
+		else
+		  {
+		    TREE_TYPE (def) = promoted_type;
+		    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+		  }
+	      }
+	    else
+	      {
+		/* If RHS is not promoted OR their types are not
+		   compatible, create NOP_EXPR that converts
+		   RHS to  promoted DEF type and perform a
+		   ZERO/SIGN EXTEND to get the required value
+		   from RHS.  */
+		ssa_name_info *info = ssa_name_info_map->get_or_insert (rhs);
+		if (info != NULL)
+		  {
+		    tree type = info->type;
+		    new_def = copy_ssa_name (rhs);
+		    SET_SSA_NAME_VAR_OR_IDENTIFIER (new_def, NULL_TREE);
+		    TREE_TYPE (def) = promoted_type;
+		    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+		    gimple *copy_stmt =
+		      zero_sign_extend_stmt (new_def, rhs,
+					     TYPE_UNSIGNED (type),
+					     TYPE_PRECISION (type));
+		    gsi2 = gsi_for_stmt (def_stmt);
+		    gsi_insert_before (&gsi2, copy_stmt, GSI_NEW_STMT);
+		    gassign *new_def_stmt = gimple_build_assign (def, code,
+								 new_def, NULL_TREE);
+		    gsi_replace (gsi, new_def_stmt, false);
+		  }
+		else
+		  {
+		    TREE_TYPE (def) = promoted_type;
+		    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+		  }
+	      }
+	  }
+	else
+	  {
+	    /* Promote def by fixing its type and make def anonymous.  */
+	    SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+	    promote_cst_in_stmt (def_stmt, promoted_type);
+	    TREE_TYPE (def) = promoted_type;
+	  }
+	break;
+      }
+
+    default:
+      do_not_promote = true;
+      break;
+    }
+
+  if (do_not_promote)
+    {
+      /* Promote def and copy (i.e. convert) the value defined
+	 by the stmt that cannot be promoted.  */
+      new_def = copy_ssa_name (def);
+      set_ssa_promoted (new_def);
+      SET_SSA_NAME_VAR_OR_IDENTIFIER (def, NULL_TREE);
+      TREE_TYPE (def) = promoted_type;
+      gimple_set_lhs (def_stmt, new_def);
+      copy_stmt = gimple_build_assign (def, NOP_EXPR,
+				       new_def, NULL_TREE);
+      gsi2 = gsi_for_stmt (def_stmt);
+      if (lookup_stmt_eh_lp (def_stmt) > 0
+	  || (gimple_code (def_stmt) == GIMPLE_CALL
+	      && gimple_call_ctrl_altering_p (def_stmt)))
+	gsi_insert_on_edge (FALLTHRU_EDGE (gimple_bb (def_stmt)),
+			    copy_stmt);
+      else
+	gsi_insert_after (&gsi2, copy_stmt, GSI_NEW_STMT);
+    }
+  reset_flow_sensitive_info (def);
+}
+
+/* Fix the (promoted) USE in stmts where USE cannot be be promoted.  */
+static unsigned int
+fixup_use (gimple *stmt, gimple_stmt_iterator *gsi,
+	   use_operand_p op, tree use)
+{
+  ssa_name_info *info = ssa_name_info_map->get_or_insert (use);
+  /* If USE is not promoted, nothing to do.  */
+  if (!info)
+    return 0;
+
+  tree promoted_type = info->promoted_type;
+  tree old_type = info->type;
+  bool do_not_promote = false;
+
+  switch (gimple_code (stmt))
+    {
+    case GIMPLE_DEBUG:
+      {
+	SET_USE (op, fold_convert (old_type, use));
+	update_stmt (stmt);
+	break;
+      }
+
+    case GIMPLE_ASM:
+    case GIMPLE_CALL:
+    case GIMPLE_RETURN:
+      {
+	/* USE cannot be promoted here.  */
+	do_not_promote = true;
+	break;
+      }
+
+    case GIMPLE_ASSIGN:
+      {
+	enum tree_code code = gimple_assign_rhs_code (stmt);
+	tree lhs = gimple_assign_lhs (stmt);
+	if (gimple_vuse (stmt) != NULL_TREE
+	    || gimple_vdef (stmt) != NULL_TREE
+	    || code == VIEW_CONVERT_EXPR
+	    || code == LROTATE_EXPR
+	    || code == RROTATE_EXPR
+	    || code == CONSTRUCTOR
+	    || code == BIT_FIELD_REF
+	    || code == COMPLEX_EXPR
+	    || VECTOR_TYPE_P (TREE_TYPE (lhs)))
+	  {
+	    do_not_promote = true;
+	  }
+	else if (TREE_CODE_CLASS (code) == tcc_comparison
+		 || truncate_use_p (code))
+	  {
+	    /* Promote the constant in comparison when other comparison
+	       operand is promoted.  All other constants are promoted as
+	       part of promoting definition in promote_ssa.  */
+	    if (TREE_CODE_CLASS (code) == tcc_comparison)
+	      promote_cst_in_stmt (stmt, promoted_type, true);
+	    /* In some stmts, value in USE has to be ZERO/SIGN
+	       Extended based on the original type for correct
+	       result.  */
+	    tree temp = make_promoted_copy (use, NULL, TREE_TYPE (use));
+	    gimple *copy_stmt =
+	      zero_sign_extend_stmt (temp, use,
+				     TYPE_UNSIGNED (old_type),
+				     TYPE_PRECISION (old_type));
+	    gsi_insert_before (gsi, copy_stmt, GSI_NEW_STMT);
+
+	    SET_USE (op, temp);
+	    update_stmt (stmt);
+	  }
+	else if (CONVERT_EXPR_CODE_P (code))
+	  {
+	    if (types_compatible_p (TREE_TYPE (lhs), promoted_type))
+	      {
+		/* Type of LHS and promoted RHS are compatible, we can
+		   convert this into ZERO/SIGN EXTEND stmt.  */
+		gimple *copy_stmt =
+		  zero_sign_extend_stmt (lhs, use,
+					 TYPE_UNSIGNED (old_type),
+					 TYPE_PRECISION (old_type));
+		set_ssa_promoted (lhs);
+		gsi_replace (gsi, copy_stmt, false);
+	      }
+	    else if (!tobe_promoted_p (lhs)
+		     || !INTEGRAL_TYPE_P (TREE_TYPE (lhs))
+		     || (TYPE_UNSIGNED (TREE_TYPE (use)) != TYPE_UNSIGNED (TREE_TYPE (lhs))))
+	      {
+		tree temp = make_promoted_copy (use, NULL, TREE_TYPE (use));
+		gimple *copy_stmt =
+		  zero_sign_extend_stmt (temp, use,
+					 TYPE_UNSIGNED (old_type),
+					 TYPE_PRECISION (old_type));
+		gsi_insert_before (gsi, copy_stmt, GSI_NEW_STMT);
+		SET_USE (op, temp);
+		update_stmt (stmt);
+	      }
+	  }
+	break;
+      }
+
+    case GIMPLE_COND:
+      {
+	/* In GIMPLE_COND, value in USE has to be ZERO/SIGN
+	   Extended based on the original type for correct
+	   result.  */
+	tree temp = make_promoted_copy (use, NULL, TREE_TYPE (use));
+	gimple *copy_stmt =
+	  zero_sign_extend_stmt (temp, use,
+				 TYPE_UNSIGNED (old_type),
+				 TYPE_PRECISION (old_type));
+	gsi_insert_before (gsi, copy_stmt, GSI_NEW_STMT);
+	SET_USE (op, temp);
+	promote_cst_in_stmt (stmt, promoted_type);
+	update_stmt (stmt);
+	break;
+      }
+
+    default:
+      break;
+    }
+
+  if (do_not_promote)
+    {
+      /* FOR stmts where USE cannot be promoted, create an
+	 original type copy.  */
+      tree temp;
+      temp = copy_ssa_name (use);
+      SET_SSA_NAME_VAR_OR_IDENTIFIER (temp, NULL_TREE);
+      set_ssa_promoted (temp);
+      TREE_TYPE (temp) = old_type;
+      gimple *copy_stmt = gimple_build_assign (temp, NOP_EXPR,
+					       use, NULL_TREE);
+      gsi_insert_before (gsi, copy_stmt, GSI_NEW_STMT);
+      SET_USE (op, temp);
+      update_stmt (stmt);
+    }
+  return 0;
+}
+
+
+/* Promote all the stmts in the basic block.  */
+static void
+promote_all_stmts (basic_block bb)
+{
+  gimple_stmt_iterator gsi;
+  ssa_op_iter iter;
+  tree def, use;
+  use_operand_p op;
+
+  for (gphi_iterator gpi = gsi_start_phis (bb);
+       !gsi_end_p (gpi); gsi_next (&gpi))
+    {
+      gphi *phi = gpi.phi ();
+      FOR_EACH_PHI_ARG (op, phi, iter, SSA_OP_USE)
+	{
+	  use = USE_FROM_PTR (op);
+	  if (TREE_CODE (use) == SSA_NAME
+	      && gimple_code (SSA_NAME_DEF_STMT (use)) == GIMPLE_NOP)
+	    promote_ssa (use, &gsi);
+	  fixup_use (phi, &gsi, op, use);
+	}
+
+      def = PHI_RESULT (phi);
+      promote_ssa (def, &gsi);
+    }
+  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    {
+      gimple *stmt = gsi_stmt (gsi);
+      if (is_gimple_debug (stmt))
+	continue;
+
+      FOR_EACH_SSA_USE_OPERAND (op, stmt, iter, SSA_OP_USE)
+	{
+	  use = USE_FROM_PTR (op);
+	  if (TREE_CODE (use) == SSA_NAME
+	      && gimple_code (SSA_NAME_DEF_STMT (use)) == GIMPLE_NOP)
+	    promote_ssa (use, &gsi);
+	  fixup_use (stmt, &gsi, op, use);
+	}
+
+      FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF)
+	promote_ssa (def, &gsi);
+    }
+}
+
+/* Promote use in GIMPLE_DEBUG stmts. Do this separately to avoid generating
+   different sequence with and without -g.  This can  happen when promoting
+   SSA that are defined with GIMPLE_NOP.  */
+static void
+promote_debug_stmts ()
+{
+  basic_block bb;
+  gimple_stmt_iterator gsi;
+  ssa_op_iter iter;
+  tree use;
+  use_operand_p op;
+
+  FOR_EACH_BB_FN (bb, cfun)
+    for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+      {
+	gimple *stmt = gsi_stmt (gsi);
+	if (!is_gimple_debug (stmt))
+	  continue;
+	FOR_EACH_SSA_USE_OPERAND (op, stmt, iter, SSA_OP_USE)
+	  {
+	    use = USE_FROM_PTR (op);
+	    fixup_use (stmt, &gsi, op, use);
+	  }
+      }
+}
+
+
+class type_promotion_dom_walker : public dom_walker
+{
+public:
+  type_promotion_dom_walker (cdi_direction direction)
+    : dom_walker (direction) {}
+  virtual void before_dom_children (basic_block bb)
+    {
+      promote_all_stmts (bb);
+    }
+};
+
+/* Main entry point to the pass.  */
+static unsigned int
+execute_type_promotion (void)
+{
+  n_ssa_val = num_ssa_names;
+  ssa_name_info_map = new hash_map<tree, ssa_name_info *>;
+  ssa_to_be_promoted_bitmap = sbitmap_alloc (n_ssa_val);
+  bitmap_clear (ssa_to_be_promoted_bitmap);
+
+  /* Create the obstack where ssa_name_info will reside.  */
+  gcc_obstack_init (&ssa_name_info_obstack);
+
+  calculate_dominance_info (CDI_DOMINATORS);
+  /* Walk the CFG in dominator order.  */
+  type_promotion_dom_walker (CDI_DOMINATORS)
+    .walk (ENTRY_BLOCK_PTR_FOR_FN (cfun));
+  promote_debug_stmts ();
+  gsi_commit_edge_inserts ();
+
+  obstack_free (&ssa_name_info_obstack, NULL);
+  sbitmap_free (ssa_to_be_promoted_bitmap);
+  delete ssa_name_info_map;
+  return 0;
+}
+
+namespace {
+const pass_data pass_data_type_promotion =
+{
+  GIMPLE_PASS, /* type */
+  "promotion", /* name */
+  OPTGROUP_NONE, /* optinfo_flags */
+  TV_TREE_TYPE_PROMOTE, /* tv_id */
+  PROP_ssa, /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  (TODO_cleanup_cfg | TODO_update_ssa | TODO_verify_all),
+};
+
+class pass_type_promotion : public gimple_opt_pass
+{
+public:
+  pass_type_promotion (gcc::context *ctxt)
+    : gimple_opt_pass (pass_data_type_promotion, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  opt_pass * clone () { return new pass_type_promotion (m_ctxt); }
+  virtual bool gate (function *) { return flag_tree_type_promote != 0; }
+  virtual unsigned int execute (function *)
+    {
+      return execute_type_promotion ();
+    }
+
+}; // class pass_type_promotion
+
+} // anon namespace
+
+gimple_opt_pass *
+make_pass_type_promote (gcc::context *ctxt)
+{
+  return new pass_type_promotion (ctxt);
+}
+
diff --git a/gcc/passes.def b/gcc/passes.def
index 36d2b3b..78c463a 100644
--- a/gcc/passes.def
+++ b/gcc/passes.def
@@ -272,6 +272,7 @@ along with GCC; see the file COPYING3.  If not see
       POP_INSERT_PASSES ()
       NEXT_PASS (pass_simduid_cleanup);
       NEXT_PASS (pass_lower_vector_ssa);
+      NEXT_PASS (pass_type_promote);
       NEXT_PASS (pass_cse_reciprocals);
       NEXT_PASS (pass_reassoc);
       NEXT_PASS (pass_strength_reduction);
diff --git a/gcc/timevar.def b/gcc/timevar.def
index b429faf..a8d40c3 100644
--- a/gcc/timevar.def
+++ b/gcc/timevar.def
@@ -278,6 +278,7 @@ DEFTIMEVAR (TV_VTABLE_VERIFICATION   , "vtable verification")
 DEFTIMEVAR (TV_TREE_UBSAN            , "tree ubsan")
 DEFTIMEVAR (TV_INITIALIZE_RTL        , "initialize rtl")
 DEFTIMEVAR (TV_GIMPLE_LADDRESS       , "address lowering")
+DEFTIMEVAR (TV_TREE_TYPE_PROMOTE     , "tree type promote")
 
 /* Everything else in rest_of_compilation not included above.  */
 DEFTIMEVAR (TV_EARLY_LOCAL	     , "early local passes")
diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h
index 333b5a7..449dd19 100644
--- a/gcc/tree-pass.h
+++ b/gcc/tree-pass.h
@@ -436,6 +436,7 @@ extern gimple_opt_pass *make_pass_fre (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_check_data_deps (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_copy_prop (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_isolate_erroneous_paths (gcc::context *ctxt);
+extern gimple_opt_pass *make_pass_type_promote (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_vrp (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_uncprop (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_return_slot (gcc::context *ctxt);
diff --git a/libiberty/cp-demangle.c b/libiberty/cp-demangle.c
index ff608a3..6722331 100644
--- a/libiberty/cp-demangle.c
+++ b/libiberty/cp-demangle.c
@@ -4353,7 +4353,7 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
 
   /* Variable used to store the current templates while a previously
      captured scope is used.  */
-  struct d_print_template *saved_templates;
+  struct d_print_template *saved_templates = NULL;
 
   /* Nonzero if templates have been stored in the above variable.  */
   int need_template_restore = 0;
-- 
1.9.1


[-- Attachment #4: 0001-Add-new-SEXT_EXPR-tree-code.patch --]
[-- Type: text/x-diff, Size: 5067 bytes --]

From c0ce364e3a422912a08189645efde46c36583753 Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandarajah@linaro.org>
Date: Thu, 22 Oct 2015 10:51:42 +1100
Subject: [PATCH 1/5] Add new SEXT_EXPR tree code

---
 gcc/cfgexpand.c         | 12 ++++++++++++
 gcc/expr.c              | 20 ++++++++++++++++++++
 gcc/fold-const.c        |  4 ++++
 gcc/tree-cfg.c          | 12 ++++++++++++
 gcc/tree-inline.c       |  1 +
 gcc/tree-pretty-print.c | 11 +++++++++++
 gcc/tree.def            |  5 +++++
 7 files changed, 65 insertions(+)

diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index eaad859..aeb64bb 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -5054,6 +5054,18 @@ expand_debug_expr (tree exp)
     case FMA_EXPR:
       return simplify_gen_ternary (FMA, mode, inner_mode, op0, op1, op2);
 
+    case SEXT_EXPR:
+      gcc_assert (CONST_INT_P (op1));
+      inner_mode = mode_for_size (INTVAL (op1), MODE_INT, 0);
+      gcc_assert (GET_MODE_BITSIZE (inner_mode) == INTVAL (op1));
+
+      if (mode != inner_mode)
+	op0 = simplify_gen_unary (SIGN_EXTEND,
+				  mode,
+				  gen_lowpart_SUBREG (inner_mode, op0),
+				  inner_mode);
+      return op0;
+
     default:
     flag_unsupported:
 #ifdef ENABLE_CHECKING
diff --git a/gcc/expr.c b/gcc/expr.c
index da68870..c2f535f 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -9318,6 +9318,26 @@ expand_expr_real_2 (sepops ops, rtx target, machine_mode tmode,
       target = expand_vec_cond_expr (type, treeop0, treeop1, treeop2, target);
       return target;
 
+    case SEXT_EXPR:
+	{
+	  machine_mode inner_mode = mode_for_size (tree_to_uhwi (treeop1),
+						   MODE_INT, 0);
+	  rtx temp, result;
+	  rtx op0 = expand_normal (treeop0);
+	  op0 = force_reg (mode, op0);
+	  if (mode != inner_mode)
+	    {
+	      result = gen_reg_rtx (mode);
+	      temp = simplify_gen_unary (SIGN_EXTEND, mode,
+					 gen_lowpart_SUBREG (inner_mode, op0),
+					 inner_mode);
+	      convert_move (result, temp, 0);
+	    }
+	  else
+	    result = op0;
+	  return result;
+	}
+
     default:
       gcc_unreachable ();
     }
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 602ea24..a149bad 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -987,6 +987,10 @@ int_const_binop_1 (enum tree_code code, const_tree arg1, const_tree parg2,
       res = wi::bit_and (arg1, arg2);
       break;
 
+    case SEXT_EXPR:
+      res = wi::sext (arg1, arg2.to_uhwi ());
+      break;
+
     case RSHIFT_EXPR:
     case LSHIFT_EXPR:
       if (wi::neg_p (arg2))
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index 8e3e810..d18b3f7 100644
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -3752,6 +3752,18 @@ verify_gimple_assign_binary (gassign *stmt)
         return false;
       }
 
+    case SEXT_EXPR:
+      {
+	if (!INTEGRAL_TYPE_P (lhs_type)
+	    || !useless_type_conversion_p (lhs_type, rhs1_type)
+	    || !tree_fits_uhwi_p (rhs2))
+	  {
+	    error ("invalid operands in sext expr");
+	    return true;
+	  }
+	return false;
+      }
+
     case VEC_WIDEN_LSHIFT_HI_EXPR:
     case VEC_WIDEN_LSHIFT_LO_EXPR:
       {
diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c
index b8269ef..e61c200 100644
--- a/gcc/tree-inline.c
+++ b/gcc/tree-inline.c
@@ -3893,6 +3893,7 @@ estimate_operator_cost (enum tree_code code, eni_weights *weights,
     case BIT_XOR_EXPR:
     case BIT_AND_EXPR:
     case BIT_NOT_EXPR:
+    case SEXT_EXPR:
 
     case TRUTH_ANDIF_EXPR:
     case TRUTH_ORIF_EXPR:
diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index 11f90051..bec9082 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -1923,6 +1923,14 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, int flags,
       }
       break;
 
+    case SEXT_EXPR:
+      pp_string (pp, "SEXT_EXPR <");
+      dump_generic_node (pp, TREE_OPERAND (node, 0), spc, flags, false);
+      pp_string (pp, ", ");
+      dump_generic_node (pp, TREE_OPERAND (node, 1), spc, flags, false);
+      pp_greater (pp);
+      break;
+
     case MODIFY_EXPR:
     case INIT_EXPR:
       dump_generic_node (pp, TREE_OPERAND (node, 0), spc, flags,
@@ -3561,6 +3569,9 @@ op_symbol_code (enum tree_code code)
     case MIN_EXPR:
       return "min";
 
+    case SEXT_EXPR:
+      return "sext";
+
     default:
       return "<<< ??? >>>";
     }
diff --git a/gcc/tree.def b/gcc/tree.def
index d0a3bd6..789cfdd 100644
--- a/gcc/tree.def
+++ b/gcc/tree.def
@@ -760,6 +760,11 @@ DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
 DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
 DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
 
+/*  Sign-extend operation.  It will sign extend first operand from
+ the sign bit specified by the second operand.  The type of the
+ result is that of the first operand.  */
+DEFTREECODE (SEXT_EXPR, "sext_expr", tcc_binary, 2)
+
 /* ANDIF and ORIF allow the second operand not to be computed if the
    value of the expression is determined from the first operand.  AND,
    OR, and XOR always compute the second operand whether its value is
-- 
1.9.1