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[54/77] Add explicit int checks for alternative optab implementations
- From: Richard Sandiford <richard dot sandiford at linaro dot org>
- To: gcc-patches at gcc dot gnu dot org
- Date: Thu, 13 Jul 2017 09:57:46 +0100
- Subject: [54/77] Add explicit int checks for alternative optab implementations
- Authentication-results: sourceware.org; auth=none
- References: <8760ewohsv.fsf@linaro.org>
expand_unop can expand narrow clz, clrsb, ctz, bswap, parity and
ffs operations using optabs for wider modes. These expansions
apply only to scalar integer modes (and not for example to vectors),
so the patch adds explicit checks for that.
2017-07-13 Richard Sandiford <richard.sandiford@linaro.org>
Alan Hayward <alan.hayward@arm.com>
David Sherwood <david.sherwood@arm.com>
gcc/
* optabs.c (widen_leading): Change the type of the mode argument
to scalar_int_mode. Use opt_scalar_int_mode for the mode iterator.
(widen_bswap): Likewise.
(expand_parity): Likewise.
(expand_ctz): Change the type of the mode argument to scalar_int_mode.
(expand_ffs): Likewise.
(epand_unop): Check for scalar integer modes before calling the
above routines.
Index: gcc/optabs.c
===================================================================
--- gcc/optabs.c 2017-07-13 09:18:46.703152916 +0100
+++ gcc/optabs.c 2017-07-13 09:18:48.024049315 +0100
@@ -2128,39 +2128,36 @@ expand_simple_unop (machine_mode mode, e
A similar operation can be used for clrsb. UNOPTAB says which operation
we are trying to expand. */
static rtx
-widen_leading (machine_mode mode, rtx op0, rtx target, optab unoptab)
+widen_leading (scalar_int_mode mode, rtx op0, rtx target, optab unoptab)
{
- enum mode_class mclass = GET_MODE_CLASS (mode);
- if (CLASS_HAS_WIDER_MODES_P (mclass))
+ opt_scalar_int_mode wider_mode_iter;
+ FOR_EACH_WIDER_MODE (wider_mode_iter, mode)
{
- machine_mode wider_mode;
- FOR_EACH_WIDER_MODE (wider_mode, mode)
+ scalar_int_mode wider_mode = *wider_mode_iter;
+ if (optab_handler (unoptab, wider_mode) != CODE_FOR_nothing)
{
- if (optab_handler (unoptab, wider_mode) != CODE_FOR_nothing)
- {
- rtx xop0, temp;
- rtx_insn *last;
+ rtx xop0, temp;
+ rtx_insn *last;
- last = get_last_insn ();
+ last = get_last_insn ();
- if (target == 0)
- target = gen_reg_rtx (mode);
- xop0 = widen_operand (op0, wider_mode, mode,
- unoptab != clrsb_optab, false);
- temp = expand_unop (wider_mode, unoptab, xop0, NULL_RTX,
- unoptab != clrsb_optab);
- if (temp != 0)
- temp = expand_binop
- (wider_mode, sub_optab, temp,
- gen_int_mode (GET_MODE_PRECISION (wider_mode)
- - GET_MODE_PRECISION (mode),
- wider_mode),
- target, true, OPTAB_DIRECT);
- if (temp == 0)
- delete_insns_since (last);
+ if (target == 0)
+ target = gen_reg_rtx (mode);
+ xop0 = widen_operand (op0, wider_mode, mode,
+ unoptab != clrsb_optab, false);
+ temp = expand_unop (wider_mode, unoptab, xop0, NULL_RTX,
+ unoptab != clrsb_optab);
+ if (temp != 0)
+ temp = expand_binop
+ (wider_mode, sub_optab, temp,
+ gen_int_mode (GET_MODE_PRECISION (wider_mode)
+ - GET_MODE_PRECISION (mode),
+ wider_mode),
+ target, true, OPTAB_DIRECT);
+ if (temp == 0)
+ delete_insns_since (last);
- return temp;
- }
+ return temp;
}
}
return 0;
@@ -2294,22 +2291,20 @@ expand_doubleword_parity (machine_mode m
as
(lshiftrt:wide (bswap:wide x) ((width wide) - (width narrow))). */
static rtx
-widen_bswap (machine_mode mode, rtx op0, rtx target)
+widen_bswap (scalar_int_mode mode, rtx op0, rtx target)
{
- enum mode_class mclass = GET_MODE_CLASS (mode);
- machine_mode wider_mode;
rtx x;
rtx_insn *last;
+ opt_scalar_int_mode wider_mode_iter;
- if (!CLASS_HAS_WIDER_MODES_P (mclass))
- return NULL_RTX;
+ FOR_EACH_WIDER_MODE (wider_mode_iter, mode)
+ if (optab_handler (bswap_optab, *wider_mode_iter) != CODE_FOR_nothing)
+ break;
- FOR_EACH_WIDER_MODE (wider_mode, mode)
- if (optab_handler (bswap_optab, wider_mode) != CODE_FOR_nothing)
- goto found;
- return NULL_RTX;
+ if (!wider_mode_iter.exists ())
+ return NULL_RTX;
- found:
+ scalar_int_mode wider_mode = *wider_mode_iter;
last = get_last_insn ();
x = widen_operand (op0, wider_mode, mode, true, true);
@@ -2360,42 +2355,40 @@ expand_doubleword_bswap (machine_mode mo
/* Try calculating (parity x) as (and (popcount x) 1), where
popcount can also be done in a wider mode. */
static rtx
-expand_parity (machine_mode mode, rtx op0, rtx target)
+expand_parity (scalar_int_mode mode, rtx op0, rtx target)
{
enum mode_class mclass = GET_MODE_CLASS (mode);
- if (CLASS_HAS_WIDER_MODES_P (mclass))
+ opt_scalar_int_mode wider_mode_iter;
+ FOR_EACH_MODE_FROM (wider_mode_iter, mode)
{
- machine_mode wider_mode;
- FOR_EACH_MODE_FROM (wider_mode, mode)
+ scalar_int_mode wider_mode = *wider_mode_iter;
+ if (optab_handler (popcount_optab, wider_mode) != CODE_FOR_nothing)
{
- if (optab_handler (popcount_optab, wider_mode) != CODE_FOR_nothing)
- {
- rtx xop0, temp;
- rtx_insn *last;
+ rtx xop0, temp;
+ rtx_insn *last;
- last = get_last_insn ();
+ last = get_last_insn ();
- if (target == 0 || GET_MODE (target) != wider_mode)
- target = gen_reg_rtx (wider_mode);
+ if (target == 0 || GET_MODE (target) != wider_mode)
+ target = gen_reg_rtx (wider_mode);
- xop0 = widen_operand (op0, wider_mode, mode, true, false);
- temp = expand_unop (wider_mode, popcount_optab, xop0, NULL_RTX,
- true);
- if (temp != 0)
- temp = expand_binop (wider_mode, and_optab, temp, const1_rtx,
- target, true, OPTAB_DIRECT);
+ xop0 = widen_operand (op0, wider_mode, mode, true, false);
+ temp = expand_unop (wider_mode, popcount_optab, xop0, NULL_RTX,
+ true);
+ if (temp != 0)
+ temp = expand_binop (wider_mode, and_optab, temp, const1_rtx,
+ target, true, OPTAB_DIRECT);
- if (temp)
- {
- if (mclass != MODE_INT
- || !TRULY_NOOP_TRUNCATION_MODES_P (mode, wider_mode))
- return convert_to_mode (mode, temp, 0);
- else
- return gen_lowpart (mode, temp);
- }
+ if (temp)
+ {
+ if (mclass != MODE_INT
+ || !TRULY_NOOP_TRUNCATION_MODES_P (mode, wider_mode))
+ return convert_to_mode (mode, temp, 0);
else
- delete_insns_since (last);
+ return gen_lowpart (mode, temp);
}
+ else
+ delete_insns_since (last);
}
}
return 0;
@@ -2414,7 +2407,7 @@ expand_parity (machine_mode mode, rtx op
less convenient for expand_ffs anyway. */
static rtx
-expand_ctz (machine_mode mode, rtx op0, rtx target)
+expand_ctz (scalar_int_mode mode, rtx op0, rtx target)
{
rtx_insn *seq;
rtx temp;
@@ -2457,7 +2450,7 @@ expand_ctz (machine_mode mode, rtx op0,
may have an undefined value in that case. If they do not give us a
convenient value, we have to generate a test and branch. */
static rtx
-expand_ffs (machine_mode mode, rtx op0, rtx target)
+expand_ffs (scalar_int_mode mode, rtx op0, rtx target)
{
HOST_WIDE_INT val = 0;
bool defined_at_zero = false;
@@ -2714,16 +2707,19 @@ expand_unop (machine_mode mode, optab un
/* Widening (or narrowing) clz needs special treatment. */
if (unoptab == clz_optab)
{
- temp = widen_leading (mode, op0, target, unoptab);
- if (temp)
- return temp;
-
- if (GET_MODE_SIZE (mode) == 2 * UNITS_PER_WORD
- && optab_handler (unoptab, word_mode) != CODE_FOR_nothing)
+ if (is_a <scalar_int_mode> (mode, &int_mode))
{
- temp = expand_doubleword_clz (mode, op0, target);
+ temp = widen_leading (int_mode, op0, target, unoptab);
if (temp)
return temp;
+
+ if (GET_MODE_SIZE (int_mode) == 2 * UNITS_PER_WORD
+ && optab_handler (unoptab, word_mode) != CODE_FOR_nothing)
+ {
+ temp = expand_doubleword_clz (int_mode, op0, target);
+ if (temp)
+ return temp;
+ }
}
goto try_libcall;
@@ -2731,9 +2727,12 @@ expand_unop (machine_mode mode, optab un
if (unoptab == clrsb_optab)
{
- temp = widen_leading (mode, op0, target, unoptab);
- if (temp)
- return temp;
+ if (is_a <scalar_int_mode> (mode, &int_mode))
+ {
+ temp = widen_leading (int_mode, op0, target, unoptab);
+ if (temp)
+ return temp;
+ }
goto try_libcall;
}
@@ -2805,16 +2804,19 @@ expand_unop (machine_mode mode, optab un
delete_insns_since (last);
}
- temp = widen_bswap (mode, op0, target);
- if (temp)
- return temp;
-
- if (GET_MODE_SIZE (mode) == 2 * UNITS_PER_WORD
- && optab_handler (unoptab, word_mode) != CODE_FOR_nothing)
+ if (is_a <scalar_int_mode> (mode, &int_mode))
{
- temp = expand_doubleword_bswap (mode, op0, target);
+ temp = widen_bswap (int_mode, op0, target);
if (temp)
return temp;
+
+ if (GET_MODE_SIZE (int_mode) == 2 * UNITS_PER_WORD
+ && optab_handler (unoptab, word_mode) != CODE_FOR_nothing)
+ {
+ temp = expand_doubleword_bswap (mode, op0, target);
+ if (temp)
+ return temp;
+ }
}
goto try_libcall;
@@ -2915,25 +2917,25 @@ expand_unop (machine_mode mode, optab un
}
/* Try calculating parity (x) as popcount (x) % 2. */
- if (unoptab == parity_optab)
+ if (unoptab == parity_optab && is_a <scalar_int_mode> (mode, &int_mode))
{
- temp = expand_parity (mode, op0, target);
+ temp = expand_parity (int_mode, op0, target);
if (temp)
return temp;
}
/* Try implementing ffs (x) in terms of clz (x). */
- if (unoptab == ffs_optab)
+ if (unoptab == ffs_optab && is_a <scalar_int_mode> (mode, &int_mode))
{
- temp = expand_ffs (mode, op0, target);
+ temp = expand_ffs (int_mode, op0, target);
if (temp)
return temp;
}
/* Try implementing ctz (x) in terms of clz (x). */
- if (unoptab == ctz_optab)
+ if (unoptab == ctz_optab && is_a <scalar_int_mode> (mode, &int_mode))
{
- temp = expand_ctz (mode, op0, target);
+ temp = expand_ctz (int_mode, op0, target);
if (temp)
return temp;
}