Re-enable zero/sign extension elimination using value range that
includes wrapped attribute.
Thanks,
Kugan
gcc/ChangeLog:
2015-01-16 Kugan Vivekanandarajah <kug...@linaro.org>
* calls.c (precompute_arguments): Check
promoted_for_signed_and_unsigned_p and set the promoted mode.
* expr.c (expand_expr_real_1): Likewise.
(promoted_for_signed_and_unsigned_p): New function.
* cfgexpand.c (expand_gimple_stmt_1): Call emit_move_insn if
SUBREG is promoted with SRP_SIGNED_AND_UNSIGNED.
* expr.h (promoted_for_signed_and_unsigned_p): New definition.
diff --git a/gcc/calls.c b/gcc/calls.c
index 36aa19f..71d2469 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -1620,7 +1620,10 @@ precompute_arguments (int num_actuals, struct arg_data
*args)
args[i].initial_value
= gen_lowpart_SUBREG (mode, args[i].value);
SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
- SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
+ if (promoted_for_signed_and_unsigned_p (args[i].tree_value))
+ SUBREG_PROMOTED_SET (args[i].initial_value,
SRP_SIGNED_AND_UNSIGNED);
+ else
+ SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
}
}
}
diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index 8926e8f..39d52db 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -3410,7 +3410,13 @@ expand_gimple_stmt_1 (gimple stmt)
GET_MODE (target), temp, unsignedp);
}
- convert_move (SUBREG_REG (target), temp, unsignedp);
+ if ((SUBREG_PROMOTED_GET (target) == SRP_SIGNED_AND_UNSIGNED)
+ && (GET_CODE (temp) == SUBREG)
+ && (GET_MODE (target) == GET_MODE (temp))
+ && (GET_MODE (SUBREG_REG (target)) == GET_MODE (SUBREG_REG
(temp))))
+ emit_move_insn (SUBREG_REG (target), SUBREG_REG (temp));
+ else
+ convert_move (SUBREG_REG (target), temp, unsignedp);
}
else if (nontemporal && emit_storent_insn (target, temp))
;
diff --git a/gcc/expr.c b/gcc/expr.c
index fc22862..48a5d13 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -174,6 +174,39 @@ static void emit_single_push_insn (machine_mode, rtx,
tree);
static void do_tablejump (rtx, machine_mode, rtx, rtx, rtx, int);
static rtx const_vector_from_tree (tree);
+/* Return TRUE if value in SSA is zero and sign extended for wider mode MODE
+ using value range information stored. Return FALSE otherwise.
+
+ This is used to check if SUBREG is zero and sign extended and to set
+ promoted mode SRP_SIGNED_AND_UNSIGNED to SUBREG. */
+
+bool
+promoted_for_signed_and_unsigned_p (tree ssa)
+{
+ wide_int min, max;
+ bool ovf;
+
+ if (ssa == NULL_TREE
+ || TREE_CODE (ssa) != SSA_NAME
+ || !INTEGRAL_TYPE_P (TREE_TYPE (ssa)))
+ return false;
+
+ /* Return FALSE if value_range is not recorded for SSA. */
+ if (get_range_info (ssa, &min, &max, &ovf) != VR_RANGE)
+ return false;
+
+ if (ovf)
+ return false;
+
+ /* Return true (to set SRP_SIGNED_AND_UNSIGNED to SUBREG) if MSB of the
+ smaller mode is not set (i.e. MSB of ssa is not set). */
+ if (!wi::neg_p (min, SIGNED) && !wi::neg_p(max, SIGNED))
+ return true;
+ else
+ return false;
+
+}
+
/* This is run to set up which modes can be used
directly in memory and to initialize the block move optab. It is run
@@ -9656,7 +9689,10 @@ expand_expr_real_1 (tree exp, rtx target, machine_mode
tmode,
temp = gen_lowpart_SUBREG (mode, decl_rtl);
SUBREG_PROMOTED_VAR_P (temp) = 1;
- SUBREG_PROMOTED_SET (temp, unsignedp);
+ if (promoted_for_signed_and_unsigned_p (ssa_name))
+ SUBREG_PROMOTED_SET (temp, SRP_SIGNED_AND_UNSIGNED);
+ else
+ SUBREG_PROMOTED_SET (temp, unsignedp);
return temp;
}
diff --git a/gcc/expr.h b/gcc/expr.h
index a7638b8..8fb1339 100644
--- a/gcc/expr.h
+++ b/gcc/expr.h
@@ -288,6 +288,7 @@ extern rtx expand_expr_real_1 (tree, rtx, machine_mode,
enum expand_modifier, rtx *, bool);
extern rtx expand_expr_real_2 (sepops, rtx, machine_mode,
enum expand_modifier);
+extern bool promoted_for_signed_and_unsigned_p (tree);
/* Generate code for computing expression EXP.
An rtx for the computed value is returned. The value is never null.
