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riscv-gcc-1
Commit d9957cf9 by Aldy Hernandez Committed by Aldy Hernandez
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tree-vrp.c (extract_range_from_unary_expr): Abstract ABS_EXPR code... 

	* tree-vrp.c (extract_range_from_unary_expr): Abstract ABS_EXPR
	code...
	(extract_range_from_abs_expr): ...here.

From-SVN: r262305
parent 108e1a85
Showing with 86 additions and 111 deletions
gcc/ChangeLog
2018-07-02 Aldy Hernandez <aldyh@redhat.com>
* tree-vrp.c (extract_range_from_unary_expr): Abstract ABS_EXPR
code...
(extract_range_from_abs_expr): ...here.
2018-07-02 Eric Botcazou <ebotcazou@adacore.com> 2018-07-02 Eric Botcazou <ebotcazou@adacore.com>
* config/i386/i386.c (ix86_finalize_stack_frame_flags): Do not overrule * config/i386/i386.c (ix86_finalize_stack_frame_flags): Do not overrule
......
gcc/tree-vrp.c
...@@ -2374,6 +2374,85 @@ extract_range_from_binary_expr_1 (value_range *vr, ...@@ -2374,6 +2374,85 @@ extract_range_from_binary_expr_1 (value_range *vr,
set_value_range (vr, type, min, max, NULL); set_value_range (vr, type, min, max, NULL);
} }
/* Calculates the absolute value of a range and puts the result in VR.
VR0 is the input range. TYPE is the type of the resulting
range. */
static void
extract_range_from_abs_expr (value_range &vr, tree type, value_range &vr0)
{
/* Pass through vr0 in the easy cases. */
if (TYPE_UNSIGNED (type)
|| value_range_nonnegative_p (&vr0))
{
copy_value_range (&vr, &vr0);
return;
}
/* For the remaining varying or symbolic ranges we can't do anything
useful. */
if (vr0.type == VR_VARYING
|| symbolic_range_p (&vr0))
{
set_value_range_to_varying (&vr);
return;
}
/* -TYPE_MIN_VALUE = TYPE_MIN_VALUE with flag_wrapv so we can't get a
useful range. */
if (!TYPE_OVERFLOW_UNDEFINED (type)
&& ((vr0.type == VR_RANGE
&& vrp_val_is_min (vr0.min))
|| (vr0.type == VR_ANTI_RANGE
&& !vrp_val_is_min (vr0.min))))
{
set_value_range_to_varying (&vr);
return;
}
/* ABS_EXPR may flip the range around, if the original range
included negative values. */
tree min, max;
if (!vrp_val_is_min (vr0.min))
min = fold_unary_to_constant (ABS_EXPR, type, vr0.min);
else
min = TYPE_MAX_VALUE (type);
if (!vrp_val_is_min (vr0.max))
max = fold_unary_to_constant (ABS_EXPR, type, vr0.max);
else
max = TYPE_MAX_VALUE (type);
int cmp = compare_values (min, max);
gcc_assert (vr0.type != VR_ANTI_RANGE);
/* If the range contains zero then we know that the minimum value in the
range will be zero. */
if (range_includes_zero_p (vr0.min, vr0.max) == 1)
{
if (cmp == 1)
max = min;
min = build_int_cst (type, 0);
}
else
{
/* If the range was reversed, swap MIN and MAX. */
if (cmp == 1)
std::swap (min, max);
}
cmp = compare_values (min, max);
if (cmp == -2 || cmp == 1)
{
/* If the new range has its limits swapped around (MIN > MAX),
then the operation caused one of them to wrap around, mark
the new range VARYING. */
set_value_range_to_varying (&vr);
}
else
set_value_range (&vr, vr0.type, min, max, NULL);
}
/* Extract range information from a unary operation CODE based on /* Extract range information from a unary operation CODE based on
the range of its operand *VR0 with type OP0_TYPE with resulting type TYPE. the range of its operand *VR0 with type OP0_TYPE with resulting type TYPE.
The resulting range is stored in *VR. */ The resulting range is stored in *VR. */
...@@ -2504,117 +2583,7 @@ extract_range_from_unary_expr (value_range *vr, ...@@ -2504,117 +2583,7 @@ extract_range_from_unary_expr (value_range *vr,
return; return;
} }
else if (code == ABS_EXPR) else if (code == ABS_EXPR)
{ return extract_range_from_abs_expr (*vr, type, vr0);
tree min, max;
int cmp;
/* Pass through vr0 in the easy cases. */
if (TYPE_UNSIGNED (type)
|| value_range_nonnegative_p (&vr0))
{
copy_value_range (vr, &vr0);
return;
}
/* For the remaining varying or symbolic ranges we can't do anything
useful. */
if (vr0.type == VR_VARYING
|| symbolic_range_p (&vr0))
{
set_value_range_to_varying (vr);
return;
}
/* -TYPE_MIN_VALUE = TYPE_MIN_VALUE with flag_wrapv so we can't get a
useful range. */
if (!TYPE_OVERFLOW_UNDEFINED (type)
&& ((vr0.type == VR_RANGE
&& vrp_val_is_min (vr0.min))
|| (vr0.type == VR_ANTI_RANGE
&& !vrp_val_is_min (vr0.min))))
{
set_value_range_to_varying (vr);
return;
}
/* ABS_EXPR may flip the range around, if the original range
included negative values. */
if (!vrp_val_is_min (vr0.min))
min = fold_unary_to_constant (code, type, vr0.min);
else
min = TYPE_MAX_VALUE (type);
if (!vrp_val_is_min (vr0.max))
max = fold_unary_to_constant (code, type, vr0.max);
else
max = TYPE_MAX_VALUE (type);
cmp = compare_values (min, max);
/* If a VR_ANTI_RANGEs contains zero, then we have
~[-INF, min(MIN, MAX)]. */
if (vr0.type == VR_ANTI_RANGE)
{
if (range_includes_zero_p (vr0.min, vr0.max) == 1)
{
/* Take the lower of the two values. */
if (cmp != 1)
max = min;
/* Create ~[-INF, min (abs(MIN), abs(MAX))]
or ~[-INF + 1, min (abs(MIN), abs(MAX))] when
flag_wrapv is set and the original anti-range doesn't include
TYPE_MIN_VALUE, remember -TYPE_MIN_VALUE = TYPE_MIN_VALUE. */
if (TYPE_OVERFLOW_WRAPS (type))
{
tree type_min_value = TYPE_MIN_VALUE (type);
min = (vr0.min != type_min_value
? int_const_binop (PLUS_EXPR, type_min_value,
build_int_cst (TREE_TYPE (type_min_value), 1))
: type_min_value);
}
else
min = TYPE_MIN_VALUE (type);
}
else
{
/* All else has failed, so create the range [0, INF], even for
flag_wrapv since TYPE_MIN_VALUE is in the original
anti-range. */
vr0.type = VR_RANGE;
min = build_int_cst (type, 0);
max = TYPE_MAX_VALUE (type);
}
}
/* If the range contains zero then we know that the minimum value in the
range will be zero. */
else if (range_includes_zero_p (vr0.min, vr0.max) == 1)
{
if (cmp == 1)
max = min;
min = build_int_cst (type, 0);
}
else
{
/* If the range was reversed, swap MIN and MAX. */
if (cmp == 1)
std::swap (min, max);
}
cmp = compare_values (min, max);
if (cmp == -2 || cmp == 1)
{
/* If the new range has its limits swapped around (MIN > MAX),
then the operation caused one of them to wrap around, mark
the new range VARYING. */
set_value_range_to_varying (vr);
}
else
set_value_range (vr, vr0.type, min, max, NULL);
return;
}
/* For unhandled operations fall back to varying. */ /* For unhandled operations fall back to varying. */
set_value_range_to_varying (vr); set_value_range_to_varying (vr);
......
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