/* Conditional Dead Call Elimination pass for the GNU compiler.
|
/* Conditional Dead Call Elimination pass for the GNU compiler.
|
Copyright (C) 2008
|
Copyright (C) 2008
|
Free Software Foundation, Inc.
|
Free Software Foundation, Inc.
|
Contributed by Xinliang David Li <davidxl@google.com>
|
Contributed by Xinliang David Li <davidxl@google.com>
|
|
|
This file is part of GCC.
|
This file is part of GCC.
|
|
|
GCC is free software; you can redistribute it and/or modify it
|
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
|
under the terms of the GNU General Public License as published by the
|
Free Software Foundation; either version 3, or (at your option) any
|
Free Software Foundation; either version 3, or (at your option) any
|
later version.
|
later version.
|
|
|
GCC is distributed in the hope that it will be useful, but WITHOUT
|
GCC is distributed in the hope that it will be useful, but WITHOUT
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
for more details.
|
for more details.
|
|
|
You should have received a copy of the GNU General Public License
|
You should have received a copy of the GNU General Public License
|
along with GCC; see the file COPYING3. If not see
|
along with GCC; see the file COPYING3. If not see
|
<http://www.gnu.org/licenses/>. */
|
<http://www.gnu.org/licenses/>. */
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|
|
#include "config.h"
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#include "config.h"
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#include "system.h"
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#include "system.h"
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#include "coretypes.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "tm.h"
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#include "ggc.h"
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#include "ggc.h"
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|
|
/* These RTL headers are needed for basic-block.h. */
|
/* These RTL headers are needed for basic-block.h. */
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#include "rtl.h"
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#include "rtl.h"
|
#include "tm_p.h"
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#include "tm_p.h"
|
#include "hard-reg-set.h"
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#include "hard-reg-set.h"
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#include "obstack.h"
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#include "obstack.h"
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#include "basic-block.h"
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#include "basic-block.h"
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|
|
#include "tree.h"
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#include "tree.h"
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#include "diagnostic.h"
|
#include "diagnostic.h"
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#include "tree-flow.h"
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#include "tree-flow.h"
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#include "gimple.h"
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#include "gimple.h"
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#include "tree-dump.h"
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#include "tree-dump.h"
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#include "tree-pass.h"
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#include "tree-pass.h"
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#include "timevar.h"
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#include "timevar.h"
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#include "flags.h"
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#include "flags.h"
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|
|
|
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/* Conditional dead call elimination
|
/* Conditional dead call elimination
|
|
|
Some builtin functions can set errno on error conditions, but they
|
Some builtin functions can set errno on error conditions, but they
|
are otherwise pure. If the result of a call to such a function is
|
are otherwise pure. If the result of a call to such a function is
|
not used, the compiler can still not eliminate the call without
|
not used, the compiler can still not eliminate the call without
|
powerful interprocedural analysis to prove that the errno is not
|
powerful interprocedural analysis to prove that the errno is not
|
checked. However, if the conditions under which the error occurs
|
checked. However, if the conditions under which the error occurs
|
are known, the compiler can conditionally dead code eliminate the
|
are known, the compiler can conditionally dead code eliminate the
|
calls by shrink-wrapping the semi-dead calls into the error condition:
|
calls by shrink-wrapping the semi-dead calls into the error condition:
|
|
|
built_in_call (args)
|
built_in_call (args)
|
==>
|
==>
|
if (error_cond (args))
|
if (error_cond (args))
|
built_in_call (args)
|
built_in_call (args)
|
|
|
An actual simple example is :
|
An actual simple example is :
|
log (x); // Mostly dead call
|
log (x); // Mostly dead call
|
==>
|
==>
|
if (x < 0)
|
if (x < 0)
|
log (x);
|
log (x);
|
With this change, call to log (x) is effectively eliminated, as
|
With this change, call to log (x) is effectively eliminated, as
|
in majority of the cases, log won't be called with x out of
|
in majority of the cases, log won't be called with x out of
|
range. The branch is totally predictable, so the branch cost
|
range. The branch is totally predictable, so the branch cost
|
is low.
|
is low.
|
|
|
Note that library functions are not supposed to clear errno to zero without
|
Note that library functions are not supposed to clear errno to zero without
|
error. See IEEE Std 1003.1, section 2.3 Error Numbers, and section 7.5:3 of
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error. See IEEE Std 1003.1, section 2.3 Error Numbers, and section 7.5:3 of
|
ISO/IEC 9899 (C99).
|
ISO/IEC 9899 (C99).
|
|
|
The condition wrapping the builtin call is conservatively set to avoid too
|
The condition wrapping the builtin call is conservatively set to avoid too
|
aggressive (wrong) shrink wrapping. The optimization is called conditional
|
aggressive (wrong) shrink wrapping. The optimization is called conditional
|
dead call elimination because the call is eliminated under the condition
|
dead call elimination because the call is eliminated under the condition
|
that the input arguments would not lead to domain or range error (for
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that the input arguments would not lead to domain or range error (for
|
instance when x <= 0 for a log (x) call), however the chances that the error
|
instance when x <= 0 for a log (x) call), however the chances that the error
|
condition is hit is very low (those builtin calls which are conditionally
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condition is hit is very low (those builtin calls which are conditionally
|
dead are usually part of the C++ abstraction penalty exposed after
|
dead are usually part of the C++ abstraction penalty exposed after
|
inlining). */
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inlining). */
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|
|
|
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/* A structure for representing input domain of
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/* A structure for representing input domain of
|
a function argument in integer. If the lower
|
a function argument in integer. If the lower
|
bound is -inf, has_lb is set to false. If the
|
bound is -inf, has_lb is set to false. If the
|
upper bound is +inf, has_ub is false.
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upper bound is +inf, has_ub is false.
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is_lb_inclusive and is_ub_inclusive are flags
|
is_lb_inclusive and is_ub_inclusive are flags
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to indicate if lb and ub value are inclusive
|
to indicate if lb and ub value are inclusive
|
respectively. */
|
respectively. */
|
|
|
typedef struct input_domain
|
typedef struct input_domain
|
{
|
{
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int lb;
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int lb;
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int ub;
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int ub;
|
bool has_lb;
|
bool has_lb;
|
bool has_ub;
|
bool has_ub;
|
bool is_lb_inclusive;
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bool is_lb_inclusive;
|
bool is_ub_inclusive;
|
bool is_ub_inclusive;
|
} inp_domain;
|
} inp_domain;
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|
|
/* A helper function to construct and return an input
|
/* A helper function to construct and return an input
|
domain object. LB is the lower bound, HAS_LB is
|
domain object. LB is the lower bound, HAS_LB is
|
a boolean flag indicating if the lower bound exists,
|
a boolean flag indicating if the lower bound exists,
|
and LB_INCLUSIVE is a boolean flag indicating if the
|
and LB_INCLUSIVE is a boolean flag indicating if the
|
lower bound is inclusive or not. UB, HAS_UB, and
|
lower bound is inclusive or not. UB, HAS_UB, and
|
UB_INCLUSIVE have the same meaning, but for upper
|
UB_INCLUSIVE have the same meaning, but for upper
|
bound of the domain. */
|
bound of the domain. */
|
|
|
static inp_domain
|
static inp_domain
|
get_domain (int lb, bool has_lb, bool lb_inclusive,
|
get_domain (int lb, bool has_lb, bool lb_inclusive,
|
int ub, bool has_ub, bool ub_inclusive)
|
int ub, bool has_ub, bool ub_inclusive)
|
{
|
{
|
inp_domain domain;
|
inp_domain domain;
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domain.lb = lb;
|
domain.lb = lb;
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domain.has_lb = has_lb;
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domain.has_lb = has_lb;
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domain.is_lb_inclusive = lb_inclusive;
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domain.is_lb_inclusive = lb_inclusive;
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domain.ub = ub;
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domain.ub = ub;
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domain.has_ub = has_ub;
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domain.has_ub = has_ub;
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domain.is_ub_inclusive = ub_inclusive;
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domain.is_ub_inclusive = ub_inclusive;
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return domain;
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return domain;
|
}
|
}
|
|
|
/* A helper function to check the target format for the
|
/* A helper function to check the target format for the
|
argument type. In this implementation, only IEEE formats
|
argument type. In this implementation, only IEEE formats
|
are supported. ARG is the call argument to be checked.
|
are supported. ARG is the call argument to be checked.
|
Returns true if the format is supported. To support other
|
Returns true if the format is supported. To support other
|
target formats, function get_no_error_domain needs to be
|
target formats, function get_no_error_domain needs to be
|
enhanced to have range bounds properly computed. Since
|
enhanced to have range bounds properly computed. Since
|
the check is cheap (very small number of candidates
|
the check is cheap (very small number of candidates
|
to be checked), the result is not cached for each float type. */
|
to be checked), the result is not cached for each float type. */
|
|
|
static bool
|
static bool
|
check_target_format (tree arg)
|
check_target_format (tree arg)
|
{
|
{
|
tree type;
|
tree type;
|
enum machine_mode mode;
|
enum machine_mode mode;
|
const struct real_format *rfmt;
|
const struct real_format *rfmt;
|
|
|
type = TREE_TYPE (arg);
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type = TREE_TYPE (arg);
|
mode = TYPE_MODE (type);
|
mode = TYPE_MODE (type);
|
rfmt = REAL_MODE_FORMAT (mode);
|
rfmt = REAL_MODE_FORMAT (mode);
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if ((mode == SFmode
|
if ((mode == SFmode
|
&& (rfmt == &ieee_single_format || rfmt == &mips_single_format
|
&& (rfmt == &ieee_single_format || rfmt == &mips_single_format
|
|| rfmt == &motorola_single_format))
|
|| rfmt == &motorola_single_format))
|
|| (mode == DFmode
|
|| (mode == DFmode
|
&& (rfmt == &ieee_double_format || rfmt == &mips_double_format
|
&& (rfmt == &ieee_double_format || rfmt == &mips_double_format
|
|| rfmt == &motorola_double_format))
|
|| rfmt == &motorola_double_format))
|
/* For long double, we can not really check XFmode
|
/* For long double, we can not really check XFmode
|
which is only defined on intel platforms.
|
which is only defined on intel platforms.
|
Candidate pre-selection using builtin function
|
Candidate pre-selection using builtin function
|
code guarantees that we are checking formats
|
code guarantees that we are checking formats
|
for long double modes: double, quad, and extended. */
|
for long double modes: double, quad, and extended. */
|
|| (mode != SFmode && mode != DFmode
|
|| (mode != SFmode && mode != DFmode
|
&& (rfmt == &ieee_quad_format
|
&& (rfmt == &ieee_quad_format
|
|| rfmt == &mips_quad_format
|
|| rfmt == &mips_quad_format
|
|| rfmt == &ieee_extended_motorola_format
|
|| rfmt == &ieee_extended_motorola_format
|
|| rfmt == &ieee_extended_intel_96_format
|
|| rfmt == &ieee_extended_intel_96_format
|
|| rfmt == &ieee_extended_intel_128_format
|
|| rfmt == &ieee_extended_intel_128_format
|
|| rfmt == &ieee_extended_intel_96_round_53_format)))
|
|| rfmt == &ieee_extended_intel_96_round_53_format)))
|
return true;
|
return true;
|
|
|
return false;
|
return false;
|
}
|
}
|
|
|
|
|
/* A helper function to help select calls to pow that are suitable for
|
/* A helper function to help select calls to pow that are suitable for
|
conditional DCE transformation. It looks for pow calls that can be
|
conditional DCE transformation. It looks for pow calls that can be
|
guided with simple conditions. Such calls either have constant base
|
guided with simple conditions. Such calls either have constant base
|
values or base values converted from integers. Returns true if
|
values or base values converted from integers. Returns true if
|
the pow call POW_CALL is a candidate. */
|
the pow call POW_CALL is a candidate. */
|
|
|
/* The maximum integer bit size for base argument of a pow call
|
/* The maximum integer bit size for base argument of a pow call
|
that is suitable for shrink-wrapping transformation. */
|
that is suitable for shrink-wrapping transformation. */
|
#define MAX_BASE_INT_BIT_SIZE 32
|
#define MAX_BASE_INT_BIT_SIZE 32
|
|
|
static bool
|
static bool
|
check_pow (gimple pow_call)
|
check_pow (gimple pow_call)
|
{
|
{
|
tree base, expn;
|
tree base, expn;
|
enum tree_code bc, ec;
|
enum tree_code bc, ec;
|
|
|
if (gimple_call_num_args (pow_call) != 2)
|
if (gimple_call_num_args (pow_call) != 2)
|
return false;
|
return false;
|
|
|
base = gimple_call_arg (pow_call, 0);
|
base = gimple_call_arg (pow_call, 0);
|
expn = gimple_call_arg (pow_call, 1);
|
expn = gimple_call_arg (pow_call, 1);
|
|
|
if (!check_target_format (expn))
|
if (!check_target_format (expn))
|
return false;
|
return false;
|
|
|
bc = TREE_CODE (base);
|
bc = TREE_CODE (base);
|
ec = TREE_CODE (expn);
|
ec = TREE_CODE (expn);
|
|
|
/* Folding candidates are not interesting.
|
/* Folding candidates are not interesting.
|
Can actually assert that it is already folded. */
|
Can actually assert that it is already folded. */
|
if (ec == REAL_CST && bc == REAL_CST)
|
if (ec == REAL_CST && bc == REAL_CST)
|
return false;
|
return false;
|
|
|
if (bc == REAL_CST)
|
if (bc == REAL_CST)
|
{
|
{
|
/* Only handle a fixed range of constant. */
|
/* Only handle a fixed range of constant. */
|
REAL_VALUE_TYPE mv;
|
REAL_VALUE_TYPE mv;
|
REAL_VALUE_TYPE bcv = TREE_REAL_CST (base);
|
REAL_VALUE_TYPE bcv = TREE_REAL_CST (base);
|
if (REAL_VALUES_EQUAL (bcv, dconst1))
|
if (REAL_VALUES_EQUAL (bcv, dconst1))
|
return false;
|
return false;
|
if (REAL_VALUES_LESS (bcv, dconst1))
|
if (REAL_VALUES_LESS (bcv, dconst1))
|
return false;
|
return false;
|
real_from_integer (&mv, TYPE_MODE (TREE_TYPE (base)), 256, 0, 1);
|
real_from_integer (&mv, TYPE_MODE (TREE_TYPE (base)), 256, 0, 1);
|
if (REAL_VALUES_LESS (mv, bcv))
|
if (REAL_VALUES_LESS (mv, bcv))
|
return false;
|
return false;
|
return true;
|
return true;
|
}
|
}
|
else if (bc == SSA_NAME)
|
else if (bc == SSA_NAME)
|
{
|
{
|
tree base_val0, base_var, type;
|
tree base_val0, base_var, type;
|
gimple base_def;
|
gimple base_def;
|
int bit_sz;
|
int bit_sz;
|
|
|
/* Only handles cases where base value is converted
|
/* Only handles cases where base value is converted
|
from integer values. */
|
from integer values. */
|
base_def = SSA_NAME_DEF_STMT (base);
|
base_def = SSA_NAME_DEF_STMT (base);
|
if (gimple_code (base_def) != GIMPLE_ASSIGN)
|
if (gimple_code (base_def) != GIMPLE_ASSIGN)
|
return false;
|
return false;
|
|
|
if (gimple_assign_rhs_code (base_def) != FLOAT_EXPR)
|
if (gimple_assign_rhs_code (base_def) != FLOAT_EXPR)
|
return false;
|
return false;
|
base_val0 = gimple_assign_rhs1 (base_def);
|
base_val0 = gimple_assign_rhs1 (base_def);
|
|
|
base_var = SSA_NAME_VAR (base_val0);
|
base_var = SSA_NAME_VAR (base_val0);
|
if (!DECL_P (base_var))
|
if (!DECL_P (base_var))
|
return false;
|
return false;
|
|
|
type = TREE_TYPE (base_var);
|
type = TREE_TYPE (base_var);
|
if (TREE_CODE (type) != INTEGER_TYPE)
|
if (TREE_CODE (type) != INTEGER_TYPE)
|
return false;
|
return false;
|
bit_sz = TYPE_PRECISION (type);
|
bit_sz = TYPE_PRECISION (type);
|
/* If the type of the base is too wide,
|
/* If the type of the base is too wide,
|
the resulting shrink wrapping condition
|
the resulting shrink wrapping condition
|
will be too conservative. */
|
will be too conservative. */
|
if (bit_sz > MAX_BASE_INT_BIT_SIZE)
|
if (bit_sz > MAX_BASE_INT_BIT_SIZE)
|
return false;
|
return false;
|
|
|
return true;
|
return true;
|
}
|
}
|
else
|
else
|
return false;
|
return false;
|
}
|
}
|
|
|
/* A helper function to help select candidate function calls that are
|
/* A helper function to help select candidate function calls that are
|
suitable for conditional DCE. Candidate functions must have single
|
suitable for conditional DCE. Candidate functions must have single
|
valid input domain in this implementation except for pow (see check_pow).
|
valid input domain in this implementation except for pow (see check_pow).
|
Returns true if the function call is a candidate. */
|
Returns true if the function call is a candidate. */
|
|
|
static bool
|
static bool
|
check_builtin_call (gimple bcall)
|
check_builtin_call (gimple bcall)
|
{
|
{
|
tree arg;
|
tree arg;
|
|
|
arg = gimple_call_arg (bcall, 0);
|
arg = gimple_call_arg (bcall, 0);
|
return check_target_format (arg);
|
return check_target_format (arg);
|
}
|
}
|
|
|
/* A helper function to determine if a builtin function call is a
|
/* A helper function to determine if a builtin function call is a
|
candidate for conditional DCE. Returns true if the builtin call
|
candidate for conditional DCE. Returns true if the builtin call
|
is a candidate. */
|
is a candidate. */
|
|
|
static bool
|
static bool
|
is_call_dce_candidate (gimple call)
|
is_call_dce_candidate (gimple call)
|
{
|
{
|
tree fn;
|
tree fn;
|
enum built_in_function fnc;
|
enum built_in_function fnc;
|
|
|
/* Only potentially dead calls are considered. */
|
/* Only potentially dead calls are considered. */
|
if (gimple_call_lhs (call))
|
if (gimple_call_lhs (call))
|
return false;
|
return false;
|
|
|
fn = gimple_call_fndecl (call);
|
fn = gimple_call_fndecl (call);
|
if (!fn
|
if (!fn
|
|| !DECL_BUILT_IN (fn)
|
|| !DECL_BUILT_IN (fn)
|
|| (DECL_BUILT_IN_CLASS (fn) != BUILT_IN_NORMAL))
|
|| (DECL_BUILT_IN_CLASS (fn) != BUILT_IN_NORMAL))
|
return false;
|
return false;
|
|
|
fnc = DECL_FUNCTION_CODE (fn);
|
fnc = DECL_FUNCTION_CODE (fn);
|
switch (fnc)
|
switch (fnc)
|
{
|
{
|
/* Trig functions. */
|
/* Trig functions. */
|
CASE_FLT_FN (BUILT_IN_ACOS):
|
CASE_FLT_FN (BUILT_IN_ACOS):
|
CASE_FLT_FN (BUILT_IN_ASIN):
|
CASE_FLT_FN (BUILT_IN_ASIN):
|
/* Hyperbolic functions. */
|
/* Hyperbolic functions. */
|
CASE_FLT_FN (BUILT_IN_ACOSH):
|
CASE_FLT_FN (BUILT_IN_ACOSH):
|
CASE_FLT_FN (BUILT_IN_ATANH):
|
CASE_FLT_FN (BUILT_IN_ATANH):
|
CASE_FLT_FN (BUILT_IN_COSH):
|
CASE_FLT_FN (BUILT_IN_COSH):
|
CASE_FLT_FN (BUILT_IN_SINH):
|
CASE_FLT_FN (BUILT_IN_SINH):
|
/* Log functions. */
|
/* Log functions. */
|
CASE_FLT_FN (BUILT_IN_LOG):
|
CASE_FLT_FN (BUILT_IN_LOG):
|
CASE_FLT_FN (BUILT_IN_LOG2):
|
CASE_FLT_FN (BUILT_IN_LOG2):
|
CASE_FLT_FN (BUILT_IN_LOG10):
|
CASE_FLT_FN (BUILT_IN_LOG10):
|
CASE_FLT_FN (BUILT_IN_LOG1P):
|
CASE_FLT_FN (BUILT_IN_LOG1P):
|
/* Exp functions. */
|
/* Exp functions. */
|
CASE_FLT_FN (BUILT_IN_EXP):
|
CASE_FLT_FN (BUILT_IN_EXP):
|
CASE_FLT_FN (BUILT_IN_EXP2):
|
CASE_FLT_FN (BUILT_IN_EXP2):
|
CASE_FLT_FN (BUILT_IN_EXP10):
|
CASE_FLT_FN (BUILT_IN_EXP10):
|
CASE_FLT_FN (BUILT_IN_EXPM1):
|
CASE_FLT_FN (BUILT_IN_EXPM1):
|
CASE_FLT_FN (BUILT_IN_POW10):
|
CASE_FLT_FN (BUILT_IN_POW10):
|
/* Sqrt. */
|
/* Sqrt. */
|
CASE_FLT_FN (BUILT_IN_SQRT):
|
CASE_FLT_FN (BUILT_IN_SQRT):
|
return check_builtin_call (call);
|
return check_builtin_call (call);
|
/* Special one: two argument pow. */
|
/* Special one: two argument pow. */
|
case BUILT_IN_POW:
|
case BUILT_IN_POW:
|
return check_pow (call);
|
return check_pow (call);
|
default:
|
default:
|
break;
|
break;
|
}
|
}
|
|
|
return false;
|
return false;
|
}
|
}
|
|
|
|
|
/* A helper function to generate gimple statements for
|
/* A helper function to generate gimple statements for
|
one bound comparison. ARG is the call argument to
|
one bound comparison. ARG is the call argument to
|
be compared with the bound, LBUB is the bound value
|
be compared with the bound, LBUB is the bound value
|
in integer, TCODE is the tree_code of the comparison,
|
in integer, TCODE is the tree_code of the comparison,
|
TEMP_NAME1/TEMP_NAME2 are names of the temporaries,
|
TEMP_NAME1/TEMP_NAME2 are names of the temporaries,
|
CONDS is a vector holding the produced GIMPLE statements,
|
CONDS is a vector holding the produced GIMPLE statements,
|
and NCONDS points to the variable holding the number
|
and NCONDS points to the variable holding the number
|
of logical comparisons. CONDS is either empty or
|
of logical comparisons. CONDS is either empty or
|
a list ended with a null tree. */
|
a list ended with a null tree. */
|
|
|
static void
|
static void
|
gen_one_condition (tree arg, int lbub,
|
gen_one_condition (tree arg, int lbub,
|
enum tree_code tcode,
|
enum tree_code tcode,
|
const char *temp_name1,
|
const char *temp_name1,
|
const char *temp_name2,
|
const char *temp_name2,
|
VEC (gimple, heap) *conds,
|
VEC (gimple, heap) *conds,
|
unsigned *nconds)
|
unsigned *nconds)
|
{
|
{
|
tree lbub_real_cst, lbub_cst, float_type;
|
tree lbub_real_cst, lbub_cst, float_type;
|
tree temp, tempn, tempc, tempcn;
|
tree temp, tempn, tempc, tempcn;
|
gimple stmt1, stmt2, stmt3;
|
gimple stmt1, stmt2, stmt3;
|
|
|
float_type = TREE_TYPE (arg);
|
float_type = TREE_TYPE (arg);
|
lbub_cst = build_int_cst (integer_type_node, lbub);
|
lbub_cst = build_int_cst (integer_type_node, lbub);
|
lbub_real_cst = build_real_from_int_cst (float_type, lbub_cst);
|
lbub_real_cst = build_real_from_int_cst (float_type, lbub_cst);
|
|
|
temp = create_tmp_var (float_type, temp_name1);
|
temp = create_tmp_var (float_type, temp_name1);
|
stmt1 = gimple_build_assign (temp, arg);
|
stmt1 = gimple_build_assign (temp, arg);
|
tempn = make_ssa_name (temp, stmt1);
|
tempn = make_ssa_name (temp, stmt1);
|
gimple_assign_set_lhs (stmt1, tempn);
|
gimple_assign_set_lhs (stmt1, tempn);
|
|
|
tempc = create_tmp_var (boolean_type_node, temp_name2);
|
tempc = create_tmp_var (boolean_type_node, temp_name2);
|
stmt2 = gimple_build_assign (tempc,
|
stmt2 = gimple_build_assign (tempc,
|
fold_build2 (tcode,
|
fold_build2 (tcode,
|
boolean_type_node,
|
boolean_type_node,
|
tempn, lbub_real_cst));
|
tempn, lbub_real_cst));
|
tempcn = make_ssa_name (tempc, stmt2);
|
tempcn = make_ssa_name (tempc, stmt2);
|
gimple_assign_set_lhs (stmt2, tempcn);
|
gimple_assign_set_lhs (stmt2, tempcn);
|
|
|
stmt3 = gimple_build_cond_from_tree (tempcn, NULL_TREE, NULL_TREE);
|
stmt3 = gimple_build_cond_from_tree (tempcn, NULL_TREE, NULL_TREE);
|
VEC_quick_push (gimple, conds, stmt1);
|
VEC_quick_push (gimple, conds, stmt1);
|
VEC_quick_push (gimple, conds, stmt2);
|
VEC_quick_push (gimple, conds, stmt2);
|
VEC_quick_push (gimple, conds, stmt3);
|
VEC_quick_push (gimple, conds, stmt3);
|
(*nconds)++;
|
(*nconds)++;
|
}
|
}
|
|
|
/* A helper function to generate GIMPLE statements for
|
/* A helper function to generate GIMPLE statements for
|
out of input domain check. ARG is the call argument
|
out of input domain check. ARG is the call argument
|
to be runtime checked, DOMAIN holds the valid domain
|
to be runtime checked, DOMAIN holds the valid domain
|
for the given function, CONDS points to the vector
|
for the given function, CONDS points to the vector
|
holding the result GIMPLE statements. *NCONDS is
|
holding the result GIMPLE statements. *NCONDS is
|
the number of logical comparisons. This function
|
the number of logical comparisons. This function
|
produces no more than two logical comparisons, one
|
produces no more than two logical comparisons, one
|
for lower bound check, one for upper bound check. */
|
for lower bound check, one for upper bound check. */
|
|
|
static void
|
static void
|
gen_conditions_for_domain (tree arg, inp_domain domain,
|
gen_conditions_for_domain (tree arg, inp_domain domain,
|
VEC (gimple, heap) *conds,
|
VEC (gimple, heap) *conds,
|
unsigned *nconds)
|
unsigned *nconds)
|
{
|
{
|
if (domain.has_lb)
|
if (domain.has_lb)
|
gen_one_condition (arg, domain.lb,
|
gen_one_condition (arg, domain.lb,
|
(domain.is_lb_inclusive
|
(domain.is_lb_inclusive
|
? LT_EXPR : LE_EXPR),
|
? LT_EXPR : LE_EXPR),
|
"DCE_COND_LB", "DCE_COND_LB_TEST",
|
"DCE_COND_LB", "DCE_COND_LB_TEST",
|
conds, nconds);
|
conds, nconds);
|
|
|
if (domain.has_ub)
|
if (domain.has_ub)
|
{
|
{
|
/* Now push a separator. */
|
/* Now push a separator. */
|
if (domain.has_lb)
|
if (domain.has_lb)
|
VEC_quick_push (gimple, conds, NULL);
|
VEC_quick_push (gimple, conds, NULL);
|
|
|
gen_one_condition (arg, domain.ub,
|
gen_one_condition (arg, domain.ub,
|
(domain.is_ub_inclusive
|
(domain.is_ub_inclusive
|
? GT_EXPR : GE_EXPR),
|
? GT_EXPR : GE_EXPR),
|
"DCE_COND_UB", "DCE_COND_UB_TEST",
|
"DCE_COND_UB", "DCE_COND_UB_TEST",
|
conds, nconds);
|
conds, nconds);
|
}
|
}
|
}
|
}
|
|
|
|
|
/* A helper function to generate condition
|
/* A helper function to generate condition
|
code for the y argument in call pow (some_const, y).
|
code for the y argument in call pow (some_const, y).
|
See candidate selection in check_pow. Since the
|
See candidate selection in check_pow. Since the
|
candidates' base values have a limited range,
|
candidates' base values have a limited range,
|
the guarded code generated for y are simple:
|
the guarded code generated for y are simple:
|
if (y > max_y)
|
if (y > max_y)
|
pow (const, y);
|
pow (const, y);
|
Note max_y can be computed separately for each
|
Note max_y can be computed separately for each
|
const base, but in this implementation, we
|
const base, but in this implementation, we
|
choose to compute it using the max base
|
choose to compute it using the max base
|
in the allowed range for the purpose of
|
in the allowed range for the purpose of
|
simplicity. BASE is the constant base value,
|
simplicity. BASE is the constant base value,
|
EXPN is the expression for the exponent argument,
|
EXPN is the expression for the exponent argument,
|
*CONDS is the vector to hold resulting statements,
|
*CONDS is the vector to hold resulting statements,
|
and *NCONDS is the number of logical conditions. */
|
and *NCONDS is the number of logical conditions. */
|
|
|
static void
|
static void
|
gen_conditions_for_pow_cst_base (tree base, tree expn,
|
gen_conditions_for_pow_cst_base (tree base, tree expn,
|
VEC (gimple, heap) *conds,
|
VEC (gimple, heap) *conds,
|
unsigned *nconds)
|
unsigned *nconds)
|
{
|
{
|
inp_domain exp_domain;
|
inp_domain exp_domain;
|
/* Validate the range of the base constant to make
|
/* Validate the range of the base constant to make
|
sure it is consistent with check_pow. */
|
sure it is consistent with check_pow. */
|
REAL_VALUE_TYPE mv;
|
REAL_VALUE_TYPE mv;
|
REAL_VALUE_TYPE bcv = TREE_REAL_CST (base);
|
REAL_VALUE_TYPE bcv = TREE_REAL_CST (base);
|
gcc_assert (!REAL_VALUES_EQUAL (bcv, dconst1)
|
gcc_assert (!REAL_VALUES_EQUAL (bcv, dconst1)
|
&& !REAL_VALUES_LESS (bcv, dconst1));
|
&& !REAL_VALUES_LESS (bcv, dconst1));
|
real_from_integer (&mv, TYPE_MODE (TREE_TYPE (base)), 256, 0, 1);
|
real_from_integer (&mv, TYPE_MODE (TREE_TYPE (base)), 256, 0, 1);
|
gcc_assert (!REAL_VALUES_LESS (mv, bcv));
|
gcc_assert (!REAL_VALUES_LESS (mv, bcv));
|
|
|
exp_domain = get_domain (0, false, false,
|
exp_domain = get_domain (0, false, false,
|
127, true, false);
|
127, true, false);
|
|
|
gen_conditions_for_domain (expn, exp_domain,
|
gen_conditions_for_domain (expn, exp_domain,
|
conds, nconds);
|
conds, nconds);
|
}
|
}
|
|
|
/* Generate error condition code for pow calls with
|
/* Generate error condition code for pow calls with
|
non constant base values. The candidates selected
|
non constant base values. The candidates selected
|
have their base argument value converted from
|
have their base argument value converted from
|
integer (see check_pow) value (1, 2, 4 bytes), and
|
integer (see check_pow) value (1, 2, 4 bytes), and
|
the max exp value is computed based on the size
|
the max exp value is computed based on the size
|
of the integer type (i.e. max possible base value).
|
of the integer type (i.e. max possible base value).
|
The resulting input domain for exp argument is thus
|
The resulting input domain for exp argument is thus
|
conservative (smaller than the max value allowed by
|
conservative (smaller than the max value allowed by
|
the runtime value of the base). BASE is the integer
|
the runtime value of the base). BASE is the integer
|
base value, EXPN is the expression for the exponent
|
base value, EXPN is the expression for the exponent
|
argument, *CONDS is the vector to hold resulting
|
argument, *CONDS is the vector to hold resulting
|
statements, and *NCONDS is the number of logical
|
statements, and *NCONDS is the number of logical
|
conditions. */
|
conditions. */
|
|
|
static void
|
static void
|
gen_conditions_for_pow_int_base (tree base, tree expn,
|
gen_conditions_for_pow_int_base (tree base, tree expn,
|
VEC (gimple, heap) *conds,
|
VEC (gimple, heap) *conds,
|
unsigned *nconds)
|
unsigned *nconds)
|
{
|
{
|
gimple base_def;
|
gimple base_def;
|
tree base_val0;
|
tree base_val0;
|
tree base_var, int_type;
|
tree base_var, int_type;
|
tree temp, tempn;
|
tree temp, tempn;
|
tree cst0;
|
tree cst0;
|
gimple stmt1, stmt2;
|
gimple stmt1, stmt2;
|
int bit_sz, max_exp;
|
int bit_sz, max_exp;
|
inp_domain exp_domain;
|
inp_domain exp_domain;
|
|
|
base_def = SSA_NAME_DEF_STMT (base);
|
base_def = SSA_NAME_DEF_STMT (base);
|
base_val0 = gimple_assign_rhs1 (base_def);
|
base_val0 = gimple_assign_rhs1 (base_def);
|
base_var = SSA_NAME_VAR (base_val0);
|
base_var = SSA_NAME_VAR (base_val0);
|
int_type = TREE_TYPE (base_var);
|
int_type = TREE_TYPE (base_var);
|
bit_sz = TYPE_PRECISION (int_type);
|
bit_sz = TYPE_PRECISION (int_type);
|
gcc_assert (bit_sz > 0
|
gcc_assert (bit_sz > 0
|
&& bit_sz <= MAX_BASE_INT_BIT_SIZE);
|
&& bit_sz <= MAX_BASE_INT_BIT_SIZE);
|
|
|
/* Determine the max exp argument value according to
|
/* Determine the max exp argument value according to
|
the size of the base integer. The max exp value
|
the size of the base integer. The max exp value
|
is conservatively estimated assuming IEEE754 double
|
is conservatively estimated assuming IEEE754 double
|
precision format. */
|
precision format. */
|
if (bit_sz == 8)
|
if (bit_sz == 8)
|
max_exp = 128;
|
max_exp = 128;
|
else if (bit_sz == 16)
|
else if (bit_sz == 16)
|
max_exp = 64;
|
max_exp = 64;
|
else
|
else
|
{
|
{
|
gcc_assert (bit_sz == MAX_BASE_INT_BIT_SIZE);
|
gcc_assert (bit_sz == MAX_BASE_INT_BIT_SIZE);
|
max_exp = 32;
|
max_exp = 32;
|
}
|
}
|
|
|
/* For pow ((double)x, y), generate the following conditions:
|
/* For pow ((double)x, y), generate the following conditions:
|
cond 1:
|
cond 1:
|
temp1 = x;
|
temp1 = x;
|
if (temp1 <= 0)
|
if (temp1 <= 0)
|
|
|
cond 2:
|
cond 2:
|
temp2 = y;
|
temp2 = y;
|
if (temp2 > max_exp_real_cst) */
|
if (temp2 > max_exp_real_cst) */
|
|
|
/* Generate condition in reverse order -- first
|
/* Generate condition in reverse order -- first
|
the condition for the exp argument. */
|
the condition for the exp argument. */
|
|
|
exp_domain = get_domain (0, false, false,
|
exp_domain = get_domain (0, false, false,
|
max_exp, true, true);
|
max_exp, true, true);
|
|
|
gen_conditions_for_domain (expn, exp_domain,
|
gen_conditions_for_domain (expn, exp_domain,
|
conds, nconds);
|
conds, nconds);
|
|
|
/* Now generate condition for the base argument.
|
/* Now generate condition for the base argument.
|
Note it does not use the helper function
|
Note it does not use the helper function
|
gen_conditions_for_domain because the base
|
gen_conditions_for_domain because the base
|
type is integer. */
|
type is integer. */
|
|
|
/* Push a separator. */
|
/* Push a separator. */
|
VEC_quick_push (gimple, conds, NULL);
|
VEC_quick_push (gimple, conds, NULL);
|
|
|
temp = create_tmp_var (int_type, "DCE_COND1");
|
temp = create_tmp_var (int_type, "DCE_COND1");
|
cst0 = build_int_cst (int_type, 0);
|
cst0 = build_int_cst (int_type, 0);
|
stmt1 = gimple_build_assign (temp, base_val0);
|
stmt1 = gimple_build_assign (temp, base_val0);
|
tempn = make_ssa_name (temp, stmt1);
|
tempn = make_ssa_name (temp, stmt1);
|
gimple_assign_set_lhs (stmt1, tempn);
|
gimple_assign_set_lhs (stmt1, tempn);
|
stmt2 = gimple_build_cond (LE_EXPR, tempn, cst0, NULL_TREE, NULL_TREE);
|
stmt2 = gimple_build_cond (LE_EXPR, tempn, cst0, NULL_TREE, NULL_TREE);
|
|
|
VEC_quick_push (gimple, conds, stmt1);
|
VEC_quick_push (gimple, conds, stmt1);
|
VEC_quick_push (gimple, conds, stmt2);
|
VEC_quick_push (gimple, conds, stmt2);
|
(*nconds)++;
|
(*nconds)++;
|
}
|
}
|
|
|
/* Method to generate conditional statements for guarding conditionally
|
/* Method to generate conditional statements for guarding conditionally
|
dead calls to pow. One or more statements can be generated for
|
dead calls to pow. One or more statements can be generated for
|
each logical condition. Statement groups of different conditions
|
each logical condition. Statement groups of different conditions
|
are separated by a NULL tree and they are stored in the VEC
|
are separated by a NULL tree and they are stored in the VEC
|
conds. The number of logical conditions are stored in *nconds.
|
conds. The number of logical conditions are stored in *nconds.
|
|
|
See C99 standard, 7.12.7.4:2, for description of pow (x, y).
|
See C99 standard, 7.12.7.4:2, for description of pow (x, y).
|
The precise condition for domain errors are complex. In this
|
The precise condition for domain errors are complex. In this
|
implementation, a simplified (but conservative) valid domain
|
implementation, a simplified (but conservative) valid domain
|
for x and y are used: x is positive to avoid dom errors, while
|
for x and y are used: x is positive to avoid dom errors, while
|
y is smaller than a upper bound (depending on x) to avoid range
|
y is smaller than a upper bound (depending on x) to avoid range
|
errors. Runtime code is generated to check x (if not constant)
|
errors. Runtime code is generated to check x (if not constant)
|
and y against the valid domain. If it is out, jump to the call,
|
and y against the valid domain. If it is out, jump to the call,
|
otherwise the call is bypassed. POW_CALL is the call statement,
|
otherwise the call is bypassed. POW_CALL is the call statement,
|
*CONDS is a vector holding the resulting condition statements,
|
*CONDS is a vector holding the resulting condition statements,
|
and *NCONDS is the number of logical conditions. */
|
and *NCONDS is the number of logical conditions. */
|
|
|
static void
|
static void
|
gen_conditions_for_pow (gimple pow_call, VEC (gimple, heap) *conds,
|
gen_conditions_for_pow (gimple pow_call, VEC (gimple, heap) *conds,
|
unsigned *nconds)
|
unsigned *nconds)
|
{
|
{
|
tree base, expn;
|
tree base, expn;
|
enum tree_code bc;
|
enum tree_code bc;
|
|
|
#ifdef ENABLE_CHECKING
|
#ifdef ENABLE_CHECKING
|
gcc_assert (check_pow (pow_call));
|
gcc_assert (check_pow (pow_call));
|
#endif
|
#endif
|
|
|
*nconds = 0;
|
*nconds = 0;
|
|
|
base = gimple_call_arg (pow_call, 0);
|
base = gimple_call_arg (pow_call, 0);
|
expn = gimple_call_arg (pow_call, 1);
|
expn = gimple_call_arg (pow_call, 1);
|
|
|
bc = TREE_CODE (base);
|
bc = TREE_CODE (base);
|
|
|
if (bc == REAL_CST)
|
if (bc == REAL_CST)
|
gen_conditions_for_pow_cst_base (base, expn, conds, nconds);
|
gen_conditions_for_pow_cst_base (base, expn, conds, nconds);
|
else if (bc == SSA_NAME)
|
else if (bc == SSA_NAME)
|
gen_conditions_for_pow_int_base (base, expn, conds, nconds);
|
gen_conditions_for_pow_int_base (base, expn, conds, nconds);
|
else
|
else
|
gcc_unreachable ();
|
gcc_unreachable ();
|
}
|
}
|
|
|
/* A helper routine to help computing the valid input domain
|
/* A helper routine to help computing the valid input domain
|
for a builtin function. See C99 7.12.7 for details. In this
|
for a builtin function. See C99 7.12.7 for details. In this
|
implementation, we only handle single region domain. The
|
implementation, we only handle single region domain. The
|
resulting region can be conservative (smaller) than the actual
|
resulting region can be conservative (smaller) than the actual
|
one and rounded to integers. Some of the bounds are documented
|
one and rounded to integers. Some of the bounds are documented
|
in the standard, while other limit constants are computed
|
in the standard, while other limit constants are computed
|
assuming IEEE floating point format (for SF and DF modes).
|
assuming IEEE floating point format (for SF and DF modes).
|
Since IEEE only sets minimum requirements for long double format,
|
Since IEEE only sets minimum requirements for long double format,
|
different long double formats exist under different implementations
|
different long double formats exist under different implementations
|
(e.g, 64 bit double precision (DF), 80 bit double-extended
|
(e.g, 64 bit double precision (DF), 80 bit double-extended
|
precision (XF), and 128 bit quad precision (QF) ). For simplicity,
|
precision (XF), and 128 bit quad precision (QF) ). For simplicity,
|
in this implementation, the computed bounds for long double assume
|
in this implementation, the computed bounds for long double assume
|
64 bit format (DF), and are therefore conservative. Another
|
64 bit format (DF), and are therefore conservative. Another
|
assumption is that single precision float type is always SF mode,
|
assumption is that single precision float type is always SF mode,
|
and double type is DF mode. This function is quite
|
and double type is DF mode. This function is quite
|
implementation specific, so it may not be suitable to be part of
|
implementation specific, so it may not be suitable to be part of
|
builtins.c. This needs to be revisited later to see if it can
|
builtins.c. This needs to be revisited later to see if it can
|
be leveraged in x87 assembly expansion. */
|
be leveraged in x87 assembly expansion. */
|
|
|
static inp_domain
|
static inp_domain
|
get_no_error_domain (enum built_in_function fnc)
|
get_no_error_domain (enum built_in_function fnc)
|
{
|
{
|
switch (fnc)
|
switch (fnc)
|
{
|
{
|
/* Trig functions: return [-1, +1] */
|
/* Trig functions: return [-1, +1] */
|
CASE_FLT_FN (BUILT_IN_ACOS):
|
CASE_FLT_FN (BUILT_IN_ACOS):
|
CASE_FLT_FN (BUILT_IN_ASIN):
|
CASE_FLT_FN (BUILT_IN_ASIN):
|
return get_domain (-1, true, true,
|
return get_domain (-1, true, true,
|
1, true, true);
|
1, true, true);
|
/* Hyperbolic functions. */
|
/* Hyperbolic functions. */
|
CASE_FLT_FN (BUILT_IN_ACOSH):
|
CASE_FLT_FN (BUILT_IN_ACOSH):
|
/* acosh: [1, +inf) */
|
/* acosh: [1, +inf) */
|
return get_domain (1, true, true,
|
return get_domain (1, true, true,
|
1, false, false);
|
1, false, false);
|
CASE_FLT_FN (BUILT_IN_ATANH):
|
CASE_FLT_FN (BUILT_IN_ATANH):
|
/* atanh: (-1, +1) */
|
/* atanh: (-1, +1) */
|
return get_domain (-1, true, false,
|
return get_domain (-1, true, false,
|
1, true, false);
|
1, true, false);
|
case BUILT_IN_COSHF:
|
case BUILT_IN_COSHF:
|
case BUILT_IN_SINHF:
|
case BUILT_IN_SINHF:
|
/* coshf: (-89, +89) */
|
/* coshf: (-89, +89) */
|
return get_domain (-89, true, false,
|
return get_domain (-89, true, false,
|
89, true, false);
|
89, true, false);
|
case BUILT_IN_COSH:
|
case BUILT_IN_COSH:
|
case BUILT_IN_SINH:
|
case BUILT_IN_SINH:
|
case BUILT_IN_COSHL:
|
case BUILT_IN_COSHL:
|
case BUILT_IN_SINHL:
|
case BUILT_IN_SINHL:
|
/* cosh: (-710, +710) */
|
/* cosh: (-710, +710) */
|
return get_domain (-710, true, false,
|
return get_domain (-710, true, false,
|
710, true, false);
|
710, true, false);
|
/* Log functions: (0, +inf) */
|
/* Log functions: (0, +inf) */
|
CASE_FLT_FN (BUILT_IN_LOG):
|
CASE_FLT_FN (BUILT_IN_LOG):
|
CASE_FLT_FN (BUILT_IN_LOG2):
|
CASE_FLT_FN (BUILT_IN_LOG2):
|
CASE_FLT_FN (BUILT_IN_LOG10):
|
CASE_FLT_FN (BUILT_IN_LOG10):
|
return get_domain (0, true, false,
|
return get_domain (0, true, false,
|
0, false, false);
|
0, false, false);
|
CASE_FLT_FN (BUILT_IN_LOG1P):
|
CASE_FLT_FN (BUILT_IN_LOG1P):
|
return get_domain (-1, true, false,
|
return get_domain (-1, true, false,
|
0, false, false);
|
0, false, false);
|
/* Exp functions. */
|
/* Exp functions. */
|
case BUILT_IN_EXPF:
|
case BUILT_IN_EXPF:
|
case BUILT_IN_EXPM1F:
|
case BUILT_IN_EXPM1F:
|
/* expf: (-inf, 88) */
|
/* expf: (-inf, 88) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
88, true, false);
|
88, true, false);
|
case BUILT_IN_EXP:
|
case BUILT_IN_EXP:
|
case BUILT_IN_EXPM1:
|
case BUILT_IN_EXPM1:
|
case BUILT_IN_EXPL:
|
case BUILT_IN_EXPL:
|
case BUILT_IN_EXPM1L:
|
case BUILT_IN_EXPM1L:
|
/* exp: (-inf, 709) */
|
/* exp: (-inf, 709) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
709, true, false);
|
709, true, false);
|
case BUILT_IN_EXP2F:
|
case BUILT_IN_EXP2F:
|
/* exp2f: (-inf, 128) */
|
/* exp2f: (-inf, 128) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
128, true, false);
|
128, true, false);
|
case BUILT_IN_EXP2:
|
case BUILT_IN_EXP2:
|
case BUILT_IN_EXP2L:
|
case BUILT_IN_EXP2L:
|
/* exp2: (-inf, 1024) */
|
/* exp2: (-inf, 1024) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
1024, true, false);
|
1024, true, false);
|
case BUILT_IN_EXP10F:
|
case BUILT_IN_EXP10F:
|
case BUILT_IN_POW10F:
|
case BUILT_IN_POW10F:
|
/* exp10f: (-inf, 38) */
|
/* exp10f: (-inf, 38) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
38, true, false);
|
38, true, false);
|
case BUILT_IN_EXP10:
|
case BUILT_IN_EXP10:
|
case BUILT_IN_POW10:
|
case BUILT_IN_POW10:
|
case BUILT_IN_EXP10L:
|
case BUILT_IN_EXP10L:
|
case BUILT_IN_POW10L:
|
case BUILT_IN_POW10L:
|
/* exp10: (-inf, 308) */
|
/* exp10: (-inf, 308) */
|
return get_domain (-1, false, false,
|
return get_domain (-1, false, false,
|
308, true, false);
|
308, true, false);
|
/* sqrt: [0, +inf) */
|
/* sqrt: [0, +inf) */
|
CASE_FLT_FN (BUILT_IN_SQRT):
|
CASE_FLT_FN (BUILT_IN_SQRT):
|
return get_domain (0, true, true,
|
return get_domain (0, true, true,
|
0, false, false);
|
0, false, false);
|
default:
|
default:
|
gcc_unreachable ();
|
gcc_unreachable ();
|
}
|
}
|
|
|
gcc_unreachable ();
|
gcc_unreachable ();
|
}
|
}
|
|
|
/* The function to generate shrink wrap conditions for a partially
|
/* The function to generate shrink wrap conditions for a partially
|
dead builtin call whose return value is not used anywhere,
|
dead builtin call whose return value is not used anywhere,
|
but has to be kept live due to potential error condition.
|
but has to be kept live due to potential error condition.
|
BI_CALL is the builtin call, CONDS is the vector of statements
|
BI_CALL is the builtin call, CONDS is the vector of statements
|
for condition code, NCODES is the pointer to the number of
|
for condition code, NCODES is the pointer to the number of
|
logical conditions. Statements belonging to different logical
|
logical conditions. Statements belonging to different logical
|
condition are separated by NULL tree in the vector. */
|
condition are separated by NULL tree in the vector. */
|
|
|
static void
|
static void
|
gen_shrink_wrap_conditions (gimple bi_call, VEC (gimple, heap) *conds,
|
gen_shrink_wrap_conditions (gimple bi_call, VEC (gimple, heap) *conds,
|
unsigned int *nconds)
|
unsigned int *nconds)
|
{
|
{
|
gimple call;
|
gimple call;
|
tree fn;
|
tree fn;
|
enum built_in_function fnc;
|
enum built_in_function fnc;
|
|
|
gcc_assert (nconds && conds);
|
gcc_assert (nconds && conds);
|
gcc_assert (VEC_length (gimple, conds) == 0);
|
gcc_assert (VEC_length (gimple, conds) == 0);
|
gcc_assert (is_gimple_call (bi_call));
|
gcc_assert (is_gimple_call (bi_call));
|
|
|
call = bi_call;
|
call = bi_call;
|
fn = gimple_call_fndecl (call);
|
fn = gimple_call_fndecl (call);
|
gcc_assert (fn && DECL_BUILT_IN (fn));
|
gcc_assert (fn && DECL_BUILT_IN (fn));
|
fnc = DECL_FUNCTION_CODE (fn);
|
fnc = DECL_FUNCTION_CODE (fn);
|
*nconds = 0;
|
*nconds = 0;
|
|
|
if (fnc == BUILT_IN_POW)
|
if (fnc == BUILT_IN_POW)
|
gen_conditions_for_pow (call, conds, nconds);
|
gen_conditions_for_pow (call, conds, nconds);
|
else
|
else
|
{
|
{
|
tree arg;
|
tree arg;
|
inp_domain domain = get_no_error_domain (fnc);
|
inp_domain domain = get_no_error_domain (fnc);
|
*nconds = 0;
|
*nconds = 0;
|
arg = gimple_call_arg (bi_call, 0);
|
arg = gimple_call_arg (bi_call, 0);
|
gen_conditions_for_domain (arg, domain, conds, nconds);
|
gen_conditions_for_domain (arg, domain, conds, nconds);
|
}
|
}
|
|
|
return;
|
return;
|
}
|
}
|
|
|
|
|
/* Probability of the branch (to the call) is taken. */
|
/* Probability of the branch (to the call) is taken. */
|
#define ERR_PROB 0.01
|
#define ERR_PROB 0.01
|
|
|
/* The function to shrink wrap a partially dead builtin call
|
/* The function to shrink wrap a partially dead builtin call
|
whose return value is not used anywhere, but has to be kept
|
whose return value is not used anywhere, but has to be kept
|
live due to potential error condition. Returns true if the
|
live due to potential error condition. Returns true if the
|
transformation actually happens. */
|
transformation actually happens. */
|
|
|
static bool
|
static bool
|
shrink_wrap_one_built_in_call (gimple bi_call)
|
shrink_wrap_one_built_in_call (gimple bi_call)
|
{
|
{
|
gimple_stmt_iterator bi_call_bsi;
|
gimple_stmt_iterator bi_call_bsi;
|
basic_block bi_call_bb, join_tgt_bb, guard_bb, guard_bb0;
|
basic_block bi_call_bb, join_tgt_bb, guard_bb, guard_bb0;
|
edge join_tgt_in_edge_from_call, join_tgt_in_edge_fall_thru;
|
edge join_tgt_in_edge_from_call, join_tgt_in_edge_fall_thru;
|
edge bi_call_in_edge0, guard_bb_in_edge;
|
edge bi_call_in_edge0, guard_bb_in_edge;
|
VEC (gimple, heap) *conds;
|
VEC (gimple, heap) *conds;
|
unsigned tn_cond_stmts, nconds;
|
unsigned tn_cond_stmts, nconds;
|
unsigned ci;
|
unsigned ci;
|
gimple cond_expr = NULL;
|
gimple cond_expr = NULL;
|
gimple cond_expr_start;
|
gimple cond_expr_start;
|
tree bi_call_label_decl;
|
tree bi_call_label_decl;
|
gimple bi_call_label;
|
gimple bi_call_label;
|
|
|
conds = VEC_alloc (gimple, heap, 12);
|
conds = VEC_alloc (gimple, heap, 12);
|
gen_shrink_wrap_conditions (bi_call, conds, &nconds);
|
gen_shrink_wrap_conditions (bi_call, conds, &nconds);
|
|
|
/* This can happen if the condition generator decides
|
/* This can happen if the condition generator decides
|
it is not beneficial to do the transformation. Just
|
it is not beneficial to do the transformation. Just
|
return false and do not do any transformation for
|
return false and do not do any transformation for
|
the call. */
|
the call. */
|
if (nconds == 0)
|
if (nconds == 0)
|
return false;
|
return false;
|
|
|
bi_call_bb = gimple_bb (bi_call);
|
bi_call_bb = gimple_bb (bi_call);
|
|
|
/* Now find the join target bb -- split
|
/* Now find the join target bb -- split
|
bi_call_bb if needed. */
|
bi_call_bb if needed. */
|
bi_call_bsi = gsi_for_stmt (bi_call);
|
bi_call_bsi = gsi_for_stmt (bi_call);
|
|
|
join_tgt_in_edge_from_call = split_block (bi_call_bb, bi_call);
|
join_tgt_in_edge_from_call = split_block (bi_call_bb, bi_call);
|
bi_call_bsi = gsi_for_stmt (bi_call);
|
bi_call_bsi = gsi_for_stmt (bi_call);
|
|
|
join_tgt_bb = join_tgt_in_edge_from_call->dest;
|
join_tgt_bb = join_tgt_in_edge_from_call->dest;
|
|
|
/* Now it is time to insert the first conditional expression
|
/* Now it is time to insert the first conditional expression
|
into bi_call_bb and split this bb so that bi_call is
|
into bi_call_bb and split this bb so that bi_call is
|
shrink-wrapped. */
|
shrink-wrapped. */
|
tn_cond_stmts = VEC_length (gimple, conds);
|
tn_cond_stmts = VEC_length (gimple, conds);
|
cond_expr = NULL;
|
cond_expr = NULL;
|
cond_expr_start = VEC_index (gimple, conds, 0);
|
cond_expr_start = VEC_index (gimple, conds, 0);
|
for (ci = 0; ci < tn_cond_stmts; ci++)
|
for (ci = 0; ci < tn_cond_stmts; ci++)
|
{
|
{
|
gimple c = VEC_index (gimple, conds, ci);
|
gimple c = VEC_index (gimple, conds, ci);
|
gcc_assert (c || ci != 0);
|
gcc_assert (c || ci != 0);
|
if (!c)
|
if (!c)
|
break;
|
break;
|
gsi_insert_before (&bi_call_bsi, c, GSI_SAME_STMT);
|
gsi_insert_before (&bi_call_bsi, c, GSI_SAME_STMT);
|
cond_expr = c;
|
cond_expr = c;
|
}
|
}
|
nconds--;
|
nconds--;
|
ci++;
|
ci++;
|
gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);
|
gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);
|
|
|
/* Now the label. */
|
/* Now the label. */
|
bi_call_label_decl = create_artificial_label (gimple_location (bi_call));
|
bi_call_label_decl = create_artificial_label (gimple_location (bi_call));
|
bi_call_label = gimple_build_label (bi_call_label_decl);
|
bi_call_label = gimple_build_label (bi_call_label_decl);
|
gsi_insert_before (&bi_call_bsi, bi_call_label, GSI_SAME_STMT);
|
gsi_insert_before (&bi_call_bsi, bi_call_label, GSI_SAME_STMT);
|
|
|
bi_call_in_edge0 = split_block (bi_call_bb, cond_expr);
|
bi_call_in_edge0 = split_block (bi_call_bb, cond_expr);
|
bi_call_in_edge0->flags &= ~EDGE_FALLTHRU;
|
bi_call_in_edge0->flags &= ~EDGE_FALLTHRU;
|
bi_call_in_edge0->flags |= EDGE_TRUE_VALUE;
|
bi_call_in_edge0->flags |= EDGE_TRUE_VALUE;
|
guard_bb0 = bi_call_bb;
|
guard_bb0 = bi_call_bb;
|
bi_call_bb = bi_call_in_edge0->dest;
|
bi_call_bb = bi_call_in_edge0->dest;
|
join_tgt_in_edge_fall_thru = make_edge (guard_bb0, join_tgt_bb,
|
join_tgt_in_edge_fall_thru = make_edge (guard_bb0, join_tgt_bb,
|
EDGE_FALSE_VALUE);
|
EDGE_FALSE_VALUE);
|
|
|
bi_call_in_edge0->probability = REG_BR_PROB_BASE * ERR_PROB;
|
bi_call_in_edge0->probability = REG_BR_PROB_BASE * ERR_PROB;
|
join_tgt_in_edge_fall_thru->probability =
|
join_tgt_in_edge_fall_thru->probability =
|
REG_BR_PROB_BASE - bi_call_in_edge0->probability;
|
REG_BR_PROB_BASE - bi_call_in_edge0->probability;
|
|
|
/* Code generation for the rest of the conditions */
|
/* Code generation for the rest of the conditions */
|
guard_bb = guard_bb0;
|
guard_bb = guard_bb0;
|
while (nconds > 0)
|
while (nconds > 0)
|
{
|
{
|
unsigned ci0;
|
unsigned ci0;
|
edge bi_call_in_edge;
|
edge bi_call_in_edge;
|
gimple_stmt_iterator guard_bsi = gsi_for_stmt (cond_expr_start);
|
gimple_stmt_iterator guard_bsi = gsi_for_stmt (cond_expr_start);
|
ci0 = ci;
|
ci0 = ci;
|
cond_expr_start = VEC_index (gimple, conds, ci0);
|
cond_expr_start = VEC_index (gimple, conds, ci0);
|
for (; ci < tn_cond_stmts; ci++)
|
for (; ci < tn_cond_stmts; ci++)
|
{
|
{
|
gimple c = VEC_index (gimple, conds, ci);
|
gimple c = VEC_index (gimple, conds, ci);
|
gcc_assert (c || ci != ci0);
|
gcc_assert (c || ci != ci0);
|
if (!c)
|
if (!c)
|
break;
|
break;
|
gsi_insert_before (&guard_bsi, c, GSI_SAME_STMT);
|
gsi_insert_before (&guard_bsi, c, GSI_SAME_STMT);
|
cond_expr = c;
|
cond_expr = c;
|
}
|
}
|
nconds--;
|
nconds--;
|
ci++;
|
ci++;
|
gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);
|
gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);
|
guard_bb_in_edge = split_block (guard_bb, cond_expr);
|
guard_bb_in_edge = split_block (guard_bb, cond_expr);
|
guard_bb_in_edge->flags &= ~EDGE_FALLTHRU;
|
guard_bb_in_edge->flags &= ~EDGE_FALLTHRU;
|
guard_bb_in_edge->flags |= EDGE_FALSE_VALUE;
|
guard_bb_in_edge->flags |= EDGE_FALSE_VALUE;
|
|
|
bi_call_in_edge = make_edge (guard_bb, bi_call_bb, EDGE_TRUE_VALUE);
|
bi_call_in_edge = make_edge (guard_bb, bi_call_bb, EDGE_TRUE_VALUE);
|
|
|
bi_call_in_edge->probability = REG_BR_PROB_BASE * ERR_PROB;
|
bi_call_in_edge->probability = REG_BR_PROB_BASE * ERR_PROB;
|
guard_bb_in_edge->probability =
|
guard_bb_in_edge->probability =
|
REG_BR_PROB_BASE - bi_call_in_edge->probability;
|
REG_BR_PROB_BASE - bi_call_in_edge->probability;
|
}
|
}
|
|
|
VEC_free (gimple, heap, conds);
|
VEC_free (gimple, heap, conds);
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
location_t loc;
|
location_t loc;
|
loc = gimple_location (bi_call);
|
loc = gimple_location (bi_call);
|
fprintf (dump_file,
|
fprintf (dump_file,
|
"%s:%d: note: function call is shrink-wrapped"
|
"%s:%d: note: function call is shrink-wrapped"
|
" into error conditions.\n",
|
" into error conditions.\n",
|
LOCATION_FILE (loc), LOCATION_LINE (loc));
|
LOCATION_FILE (loc), LOCATION_LINE (loc));
|
}
|
}
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* The top level function for conditional dead code shrink
|
/* The top level function for conditional dead code shrink
|
wrapping transformation. */
|
wrapping transformation. */
|
|
|
static bool
|
static bool
|
shrink_wrap_conditional_dead_built_in_calls (VEC (gimple, heap) *calls)
|
shrink_wrap_conditional_dead_built_in_calls (VEC (gimple, heap) *calls)
|
{
|
{
|
bool changed = false;
|
bool changed = false;
|
unsigned i = 0;
|
unsigned i = 0;
|
|
|
unsigned n = VEC_length (gimple, calls);
|
unsigned n = VEC_length (gimple, calls);
|
if (n == 0)
|
if (n == 0)
|
return false;
|
return false;
|
|
|
for (; i < n ; i++)
|
for (; i < n ; i++)
|
{
|
{
|
gimple bi_call = VEC_index (gimple, calls, i);
|
gimple bi_call = VEC_index (gimple, calls, i);
|
changed |= shrink_wrap_one_built_in_call (bi_call);
|
changed |= shrink_wrap_one_built_in_call (bi_call);
|
}
|
}
|
|
|
return changed;
|
return changed;
|
}
|
}
|
|
|
/* Pass entry points. */
|
/* Pass entry points. */
|
|
|
static unsigned int
|
static unsigned int
|
tree_call_cdce (void)
|
tree_call_cdce (void)
|
{
|
{
|
basic_block bb;
|
basic_block bb;
|
gimple_stmt_iterator i;
|
gimple_stmt_iterator i;
|
bool something_changed = false;
|
bool something_changed = false;
|
VEC (gimple, heap) *cond_dead_built_in_calls = NULL;
|
VEC (gimple, heap) *cond_dead_built_in_calls = NULL;
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
/* Collect dead call candidates. */
|
/* Collect dead call candidates. */
|
for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
|
for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
|
{
|
{
|
gimple stmt = gsi_stmt (i);
|
gimple stmt = gsi_stmt (i);
|
if (is_gimple_call (stmt)
|
if (is_gimple_call (stmt)
|
&& is_call_dce_candidate (stmt))
|
&& is_call_dce_candidate (stmt))
|
{
|
{
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file, "Found conditional dead call: ");
|
fprintf (dump_file, "Found conditional dead call: ");
|
print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
|
print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
|
fprintf (dump_file, "\n");
|
fprintf (dump_file, "\n");
|
}
|
}
|
if (cond_dead_built_in_calls == NULL)
|
if (cond_dead_built_in_calls == NULL)
|
cond_dead_built_in_calls = VEC_alloc (gimple, heap, 64);
|
cond_dead_built_in_calls = VEC_alloc (gimple, heap, 64);
|
VEC_safe_push (gimple, heap, cond_dead_built_in_calls, stmt);
|
VEC_safe_push (gimple, heap, cond_dead_built_in_calls, stmt);
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
if (cond_dead_built_in_calls == NULL)
|
if (cond_dead_built_in_calls == NULL)
|
return 0;
|
return 0;
|
|
|
something_changed
|
something_changed
|
= shrink_wrap_conditional_dead_built_in_calls (cond_dead_built_in_calls);
|
= shrink_wrap_conditional_dead_built_in_calls (cond_dead_built_in_calls);
|
|
|
VEC_free (gimple, heap, cond_dead_built_in_calls);
|
VEC_free (gimple, heap, cond_dead_built_in_calls);
|
|
|
if (something_changed)
|
if (something_changed)
|
{
|
{
|
free_dominance_info (CDI_DOMINATORS);
|
free_dominance_info (CDI_DOMINATORS);
|
free_dominance_info (CDI_POST_DOMINATORS);
|
free_dominance_info (CDI_POST_DOMINATORS);
|
/* As we introduced new control-flow we need to insert PHI-nodes
|
/* As we introduced new control-flow we need to insert PHI-nodes
|
for the call-clobbers of the remaining call. */
|
for the call-clobbers of the remaining call. */
|
mark_sym_for_renaming (gimple_vop (cfun));
|
mark_sym_for_renaming (gimple_vop (cfun));
|
return (TODO_update_ssa | TODO_cleanup_cfg | TODO_ggc_collect
|
return (TODO_update_ssa | TODO_cleanup_cfg | TODO_ggc_collect
|
| TODO_remove_unused_locals);
|
| TODO_remove_unused_locals);
|
}
|
}
|
else
|
else
|
return 0;
|
return 0;
|
}
|
}
|
|
|
static bool
|
static bool
|
gate_call_cdce (void)
|
gate_call_cdce (void)
|
{
|
{
|
/* The limit constants used in the implementation
|
/* The limit constants used in the implementation
|
assume IEEE floating point format. Other formats
|
assume IEEE floating point format. Other formats
|
can be supported in the future if needed. */
|
can be supported in the future if needed. */
|
return flag_tree_builtin_call_dce != 0 && optimize_function_for_speed_p (cfun);
|
return flag_tree_builtin_call_dce != 0 && optimize_function_for_speed_p (cfun);
|
}
|
}
|
|
|
struct gimple_opt_pass pass_call_cdce =
|
struct gimple_opt_pass pass_call_cdce =
|
{
|
{
|
{
|
{
|
GIMPLE_PASS,
|
GIMPLE_PASS,
|
"cdce", /* name */
|
"cdce", /* name */
|
gate_call_cdce, /* gate */
|
gate_call_cdce, /* gate */
|
tree_call_cdce, /* execute */
|
tree_call_cdce, /* execute */
|
NULL, /* sub */
|
NULL, /* sub */
|
NULL, /* next */
|
NULL, /* next */
|
0, /* static_pass_number */
|
0, /* static_pass_number */
|
TV_TREE_CALL_CDCE, /* tv_id */
|
TV_TREE_CALL_CDCE, /* tv_id */
|
PROP_cfg | PROP_ssa, /* properties_required */
|
PROP_cfg | PROP_ssa, /* properties_required */
|
0, /* properties_provided */
|
0, /* properties_provided */
|
0, /* properties_destroyed */
|
0, /* properties_destroyed */
|
0, /* todo_flags_start */
|
0, /* todo_flags_start */
|
TODO_dump_func | TODO_verify_ssa /* todo_flags_finish */
|
TODO_dump_func | TODO_verify_ssa /* todo_flags_finish */
|
}
|
}
|
};
|
};
|
|
|
