RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
Thanks Richard for comments.
> If you require a gassign please statically type your function
> argument as gassign * instead and remove this assert.
Sure
> As addition to Tamars good comments why do you set *cfg_changed_p to
> true? You are
> not changing the CFG afer all?
Yes, we can add it back in future if we really changed cfg, will update in v5
(include vect patch 2/3) after all test passed.
Pan
-Original Message-
From: Richard Biener
Sent: Tuesday, May 14, 2024 9:18 PM
To: Li, Pan2
Cc: gcc-patches@gcc.gnu.org; juzhe.zh...@rivai.ai; kito.ch...@gmail.com;
tamar.christ...@arm.com; Liu, Hongtao
Subject: Re: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
scalar int
On Mon, May 6, 2024 at 4:48 PM wrote:
>
> From: Pan Li
>
> This patch would like to add the middle-end presentation for the
> saturation add. Aka set the result of add to the max when overflow.
> It will take the pattern similar as below.
>
> SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
>
> Take uint8_t as example, we will have:
>
> * SAT_ADD (1, 254) => 255.
> * SAT_ADD (1, 255) => 255.
> * SAT_ADD (2, 255) => 255.
> * SAT_ADD (255, 255) => 255.
>
> Given below example for the unsigned scalar integer uint64_t:
>
> uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> {
> return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> }
>
> Before this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> long unsigned int _1;
> _Bool _2;
> long unsigned int _3;
> long unsigned int _4;
> uint64_t _7;
> long unsigned int _10;
> __complex__ long unsigned int _11;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> _1 = REALPART_EXPR <_11>;
> _10 = IMAGPART_EXPR <_11>;
> _2 = _10 != 0;
> _3 = (long unsigned int) _2;
> _4 = -_3;
> _7 = _1 | _4;
> return _7;
> ;;succ: EXIT
>
> }
>
> After this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> uint64_t _7;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _7 = .SAT_ADD (x_5(D), y_6(D)); [tail call]
> return _7;
> ;;succ: EXIT
> }
>
> We perform the tranform during widen_mult because that the sub-expr of
> SAT_ADD will be optimized to .ADD_OVERFLOW. We need to try the .SAT_ADD
> pattern first and then .ADD_OVERFLOW, or we may never catch the pattern
> .SAT_ADD. Meanwhile, the isel pass is after widen_mult and then we
> cannot perform the .SAT_ADD pattern match as the sub-expr will be
> optmized to .ADD_OVERFLOW first.
>
> The below tests are passed for this patch:
> 1. The riscv fully regression tests.
> 2. The aarch64 fully regression tests.
> 3. The x86 bootstrap tests.
> 4. The x86 fully regression tests.
>
> PR target/51492
> PR target/112600
>
> gcc/ChangeLog:
>
> * internal-fn.cc (commutative_binary_fn_p): Add type IFN_SAT_ADD
> to the return true switch case(s).
> * internal-fn.def (SAT_ADD): Add new signed optab SAT_ADD.
> * match.pd: Add unsigned SAT_ADD match.
> * optabs.def (OPTAB_NL): Remove fixed-point limitation for us/ssadd.
> * tree-ssa-math-opts.cc (gimple_unsigned_integer_sat_add): New extern
> func decl generated in match.pd match.
> (match_saturation_arith): New func impl to match the saturation arith.
> (math_opts_dom_walker::after_dom_children): Try match saturation
> arith.
>
> Signed-off-by: Pan Li
> ---
> gcc/internal-fn.cc| 1 +
> gcc/internal-fn.def | 2 ++
> gcc/match.pd | 28
> gcc/optabs.def| 4 ++--
> gcc/tree-ssa-math-opts.cc | 46 +++
> 5 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc
> index 0a7053c2286..73045ca8c8c 100644
> --- a/gcc/internal-fn.cc
> +++ b/gcc/internal-fn.cc
> @@ -4202,6 +4202,7 @@ commutative_binary_fn_p (internal_fn fn)
> case IFN_UBSAN_CHECK_MUL:
> case IFN_ADD_OVERFLOW:
> case IFN_MUL_OVERFLOW:
> +case IFN_SAT_ADD:
> case IFN_VEC_WIDEN_PLUS:
> case IFN_VEC_WIDEN_PLUS_LO:
> case IFN_VEC_WIDEN_PLUS_HI:
> diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
> index 848bb9dbff3..25badbb86e5 100644
> --- a/gcc/internal-fn.def
> +++ b/gcc/internal-fn.def
> @@ -275,6 +275,8 @@ DEF_INTERNAL_SIGNED_OPTAB_FN (MULHS, ECF_CONST |
> ECF_NOTHROW, first,
> DEF_INTERNAL_SIGNED_OPTAB_FN (MULHRS, ECF_CONST | ECF_NOTHROW, first,
> sm
Re: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
On Mon, May 6, 2024 at 4:48 PM wrote:
>
> From: Pan Li
>
> This patch would like to add the middle-end presentation for the
> saturation add. Aka set the result of add to the max when overflow.
> It will take the pattern similar as below.
>
> SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
>
> Take uint8_t as example, we will have:
>
> * SAT_ADD (1, 254) => 255.
> * SAT_ADD (1, 255) => 255.
> * SAT_ADD (2, 255) => 255.
> * SAT_ADD (255, 255) => 255.
>
> Given below example for the unsigned scalar integer uint64_t:
>
> uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> {
> return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> }
>
> Before this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> long unsigned int _1;
> _Bool _2;
> long unsigned int _3;
> long unsigned int _4;
> uint64_t _7;
> long unsigned int _10;
> __complex__ long unsigned int _11;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> _1 = REALPART_EXPR <_11>;
> _10 = IMAGPART_EXPR <_11>;
> _2 = _10 != 0;
> _3 = (long unsigned int) _2;
> _4 = -_3;
> _7 = _1 | _4;
> return _7;
> ;;succ: EXIT
>
> }
>
> After this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> uint64_t _7;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _7 = .SAT_ADD (x_5(D), y_6(D)); [tail call]
> return _7;
> ;;succ: EXIT
> }
>
> We perform the tranform during widen_mult because that the sub-expr of
> SAT_ADD will be optimized to .ADD_OVERFLOW. We need to try the .SAT_ADD
> pattern first and then .ADD_OVERFLOW, or we may never catch the pattern
> .SAT_ADD. Meanwhile, the isel pass is after widen_mult and then we
> cannot perform the .SAT_ADD pattern match as the sub-expr will be
> optmized to .ADD_OVERFLOW first.
>
> The below tests are passed for this patch:
> 1. The riscv fully regression tests.
> 2. The aarch64 fully regression tests.
> 3. The x86 bootstrap tests.
> 4. The x86 fully regression tests.
>
> PR target/51492
> PR target/112600
>
> gcc/ChangeLog:
>
> * internal-fn.cc (commutative_binary_fn_p): Add type IFN_SAT_ADD
> to the return true switch case(s).
> * internal-fn.def (SAT_ADD): Add new signed optab SAT_ADD.
> * match.pd: Add unsigned SAT_ADD match.
> * optabs.def (OPTAB_NL): Remove fixed-point limitation for us/ssadd.
> * tree-ssa-math-opts.cc (gimple_unsigned_integer_sat_add): New extern
> func decl generated in match.pd match.
> (match_saturation_arith): New func impl to match the saturation arith.
> (math_opts_dom_walker::after_dom_children): Try match saturation
> arith.
>
> Signed-off-by: Pan Li
> ---
> gcc/internal-fn.cc| 1 +
> gcc/internal-fn.def | 2 ++
> gcc/match.pd | 28
> gcc/optabs.def| 4 ++--
> gcc/tree-ssa-math-opts.cc | 46 +++
> 5 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc
> index 0a7053c2286..73045ca8c8c 100644
> --- a/gcc/internal-fn.cc
> +++ b/gcc/internal-fn.cc
> @@ -4202,6 +4202,7 @@ commutative_binary_fn_p (internal_fn fn)
> case IFN_UBSAN_CHECK_MUL:
> case IFN_ADD_OVERFLOW:
> case IFN_MUL_OVERFLOW:
> +case IFN_SAT_ADD:
> case IFN_VEC_WIDEN_PLUS:
> case IFN_VEC_WIDEN_PLUS_LO:
> case IFN_VEC_WIDEN_PLUS_HI:
> diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
> index 848bb9dbff3..25badbb86e5 100644
> --- a/gcc/internal-fn.def
> +++ b/gcc/internal-fn.def
> @@ -275,6 +275,8 @@ DEF_INTERNAL_SIGNED_OPTAB_FN (MULHS, ECF_CONST |
> ECF_NOTHROW, first,
> DEF_INTERNAL_SIGNED_OPTAB_FN (MULHRS, ECF_CONST | ECF_NOTHROW, first,
> smulhrs, umulhrs, binary)
>
> +DEF_INTERNAL_SIGNED_OPTAB_FN (SAT_ADD, ECF_CONST, first, ssadd, usadd,
> binary)
> +
> DEF_INTERNAL_COND_FN (ADD, ECF_CONST, add, binary)
> DEF_INTERNAL_COND_FN (SUB, ECF_CONST, sub, binary)
> DEF_INTERNAL_COND_FN (MUL, ECF_CONST, smul, binary)
> diff --git a/gcc/match.pd b/gcc/match.pd
> index d401e7503e6..7058e4cbe29 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -3043,6 +3043,34 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> || POINTER_TYPE_P (itype))
>&& wi::eq_p (wi::to_wide (int_cst), wi::max_value (itype))
>
> +/* Unsigned Saturation Add */
> +(match (usadd_left_part @0 @1)
> + (plus:c @0 @1)
> + (if (INTEGRAL_TYPE_P (type)
> + && TYPE_UNSIGNED (TREE_TYPE (@0))
> + && types_match (type, TREE_TYPE (@0))
> + && types_match (type, TREE_TYPE (@1)
> +
> +(match (usadd_right_part @0 @1)
> + (negate (convert (lt (plus:c @0 @1) @0)))
> + (if (INTEGRAL_TYPE_P (type)
> + && TYPE_UNSIGNED (TREE_TYPE (@0))
> + && types_match (type, TREE_TYPE (@0))
> + && types_match (type, TREE_TYPE (@1)
> +
> +(match (usadd_right_part @0 @1)
RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
> That's just a matter of matching the overflow as an additional case no?
> i.e. you can add an overload for unsigned_integer_sat_add matching the
> IFN_ ADD_OVERFLOW and using the realpart and imagpart helpers.
> I think that would be better as it avoid visiting all the statements twice
> but also
> extends the matching to some __builtin_add_overflow uses and should be fairly
> simple.
Thanks Tamar, got the point here, will have a try with overload
unsigned_integer_sat_add for that.
> Yeah, I think that's better than iterating over the statements twice. It
> also fits better
> In the existing code.
Ack, will follow the existing code.
Pan
-Original Message-
From: Tamar Christina
Sent: Monday, May 13, 2024 11:03 PM
To: Li, Pan2 ; gcc-patches@gcc.gnu.org
Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; richard.guent...@gmail.com;
Liu, Hongtao
Subject: RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
scalar int
>
> Thanks Tamer for comments.
>
> > I think OPTIMIZE_FOR_BOTH is better here, since this is a win also when
> optimizing for size.
>
> Sure thing, let me update it in v5.
>
> > Hmm why do you iterate independently over the statements? The block below
> already visits
> > Every statement doesn't it?
>
> Because it will hit .ADD_OVERFLOW first, then it will never hit SAT_ADD as the
> shape changed, or shall we put it to the previous pass ?
>
That's just a matter of matching the overflow as an additional case no?
i.e. you can add an overload for unsigned_integer_sat_add matching the
IFN_ ADD_OVERFLOW and using the realpart and imagpart helpers.
I think that would be better as it avoid visiting all the statements twice but
also
extends the matching to some __builtin_add_overflow uses and should be fairly
simple.
> > The root of your match is a BIT_IOR_EXPR expression, so I think you just
> > need to
> change the entry below to:
> >
> > case BIT_IOR_EXPR:
> > match_saturation_arith (, stmt, m_cfg_changed_p);
> > /* fall-through */
> > case BIT_XOR_EXPR:
> > match_uaddc_usubc (, stmt, code);
> > break;
>
> There are other shapes (not covered in this patch) of SAT_ADD like below
> branch
> version, the IOR should be one of the ROOT. Thus doesn't
> add case here. Then, shall we take case for each shape here ? Both works for
> me.
>
Yeah, I think that's better than iterating over the statements twice. It also
fits better
In the existing code.
Tamar.
> #define SAT_ADD_U_1(T) \
> T sat_add_u_1_##T(T x, T y) \
> { \
> return (T)(x + y) >= x ? (x + y) : -1; \
> }
>
> SAT_ADD_U_1(uint32_t)
>
> Pan
>
>
> -Original Message-
> From: Tamar Christina
> Sent: Monday, May 13, 2024 5:10 PM
> To: Li, Pan2 ; gcc-patches@gcc.gnu.org
> Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; richard.guent...@gmail.com;
> Liu, Hongtao
> Subject: RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar int
>
> Hi Pan,
>
> > -Original Message-
> > From: pan2...@intel.com
> > Sent: Monday, May 6, 2024 3:48 PM
> > To: gcc-patches@gcc.gnu.org
> > Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; Tamar Christina
> > ; richard.guent...@gmail.com;
> > hongtao@intel.com; Pan Li
> > Subject: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar
> > int
> >
> > From: Pan Li
> >
> > This patch would like to add the middle-end presentation for the
> > saturation add. Aka set the result of add to the max when overflow.
> > It will take the pattern similar as below.
> >
> > SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
> >
> > Take uint8_t as example, we will have:
> >
> > * SAT_ADD (1, 254) => 255.
> > * SAT_ADD (1, 255) => 255.
> > * SAT_ADD (2, 255) => 255.
> > * SAT_ADD (255, 255) => 255.
> >
> > Given below example for the unsigned scalar integer uint64_t:
> >
> > uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> > {
> > return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> > }
> >
> > Before this patch:
> > uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> > {
> > long unsigned int _1;
> > _Bool _2;
> > long unsigned int _3;
> > long unsigned int _4;
> > uint64_t _7;
> > long unsigned int _10;
> > __complex__ long unsigned int _11;
> >
> > ;; basic block 2, loop depth 0
> > ;;pred: ENTRY
> > _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> > _1 = REALPART_EXPR <_11>;
&
RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
>
> Thanks Tamer for comments.
>
> > I think OPTIMIZE_FOR_BOTH is better here, since this is a win also when
> optimizing for size.
>
> Sure thing, let me update it in v5.
>
> > Hmm why do you iterate independently over the statements? The block below
> already visits
> > Every statement doesn't it?
>
> Because it will hit .ADD_OVERFLOW first, then it will never hit SAT_ADD as the
> shape changed, or shall we put it to the previous pass ?
>
That's just a matter of matching the overflow as an additional case no?
i.e. you can add an overload for unsigned_integer_sat_add matching the
IFN_ ADD_OVERFLOW and using the realpart and imagpart helpers.
I think that would be better as it avoid visiting all the statements twice but
also
extends the matching to some __builtin_add_overflow uses and should be fairly
simple.
> > The root of your match is a BIT_IOR_EXPR expression, so I think you just
> > need to
> change the entry below to:
> >
> > case BIT_IOR_EXPR:
> > match_saturation_arith (, stmt, m_cfg_changed_p);
> > /* fall-through */
> > case BIT_XOR_EXPR:
> > match_uaddc_usubc (, stmt, code);
> > break;
>
> There are other shapes (not covered in this patch) of SAT_ADD like below
> branch
> version, the IOR should be one of the ROOT. Thus doesn't
> add case here. Then, shall we take case for each shape here ? Both works for
> me.
>
Yeah, I think that's better than iterating over the statements twice. It also
fits better
In the existing code.
Tamar.
> #define SAT_ADD_U_1(T) \
> T sat_add_u_1_##T(T x, T y) \
> { \
> return (T)(x + y) >= x ? (x + y) : -1; \
> }
>
> SAT_ADD_U_1(uint32_t)
>
> Pan
>
>
> -Original Message-
> From: Tamar Christina
> Sent: Monday, May 13, 2024 5:10 PM
> To: Li, Pan2 ; gcc-patches@gcc.gnu.org
> Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; richard.guent...@gmail.com;
> Liu, Hongtao
> Subject: RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar int
>
> Hi Pan,
>
> > -Original Message-
> > From: pan2...@intel.com
> > Sent: Monday, May 6, 2024 3:48 PM
> > To: gcc-patches@gcc.gnu.org
> > Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; Tamar Christina
> > ; richard.guent...@gmail.com;
> > hongtao@intel.com; Pan Li
> > Subject: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar
> > int
> >
> > From: Pan Li
> >
> > This patch would like to add the middle-end presentation for the
> > saturation add. Aka set the result of add to the max when overflow.
> > It will take the pattern similar as below.
> >
> > SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
> >
> > Take uint8_t as example, we will have:
> >
> > * SAT_ADD (1, 254) => 255.
> > * SAT_ADD (1, 255) => 255.
> > * SAT_ADD (2, 255) => 255.
> > * SAT_ADD (255, 255) => 255.
> >
> > Given below example for the unsigned scalar integer uint64_t:
> >
> > uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> > {
> > return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> > }
> >
> > Before this patch:
> > uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> > {
> > long unsigned int _1;
> > _Bool _2;
> > long unsigned int _3;
> > long unsigned int _4;
> > uint64_t _7;
> > long unsigned int _10;
> > __complex__ long unsigned int _11;
> >
> > ;; basic block 2, loop depth 0
> > ;;pred: ENTRY
> > _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> > _1 = REALPART_EXPR <_11>;
> > _10 = IMAGPART_EXPR <_11>;
> > _2 = _10 != 0;
> > _3 = (long unsigned int) _2;
> > _4 = -_3;
> > _7 = _1 | _4;
> > return _7;
> > ;;succ: EXIT
> >
> > }
> >
> > After this patch:
> > uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> > {
> > uint64_t _7;
> >
> > ;; basic block 2, loop depth 0
> > ;;pred: ENTRY
> > _7 = .SAT_ADD (x_5(D), y_6(D)); [tail call]
> > return _7;
> > ;;succ: EXIT
> > }
> >
> > We perform the tranform during widen_mult because that the sub-expr of
> > SAT_ADD will be optimized to .ADD_OVERFLOW. We need to try the .SAT_ADD
> > pattern first and then .ADD_OVERFLOW, or we may never catch the pattern
> > .SAT_ADD. Meanwhile, the isel pass is after widen_mult and then we
> > cannot perform the .SAT_ADD pattern match as the
RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
Thanks Tamer for comments.
> I think OPTIMIZE_FOR_BOTH is better here, since this is a win also when
> optimizing for size.
Sure thing, let me update it in v5.
> Hmm why do you iterate independently over the statements? The block below
> already visits
> Every statement doesn't it?
Because it will hit .ADD_OVERFLOW first, then it will never hit SAT_ADD as the
shape changed, or shall we put it to the previous pass ?
> The root of your match is a BIT_IOR_EXPR expression, so I think you just need
> to change the entry below to:
>
> case BIT_IOR_EXPR:
> match_saturation_arith (, stmt, m_cfg_changed_p);
> /* fall-through */
> case BIT_XOR_EXPR:
> match_uaddc_usubc (, stmt, code);
> break;
There are other shapes (not covered in this patch) of SAT_ADD like below branch
version, the IOR should be one of the ROOT. Thus doesn't
add case here. Then, shall we take case for each shape here ? Both works for
me.
#define SAT_ADD_U_1(T) \
T sat_add_u_1_##T(T x, T y) \
{ \
return (T)(x + y) >= x ? (x + y) : -1; \
}
SAT_ADD_U_1(uint32_t)
Pan
-Original Message-
From: Tamar Christina
Sent: Monday, May 13, 2024 5:10 PM
To: Li, Pan2 ; gcc-patches@gcc.gnu.org
Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; richard.guent...@gmail.com;
Liu, Hongtao
Subject: RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
scalar int
Hi Pan,
> -Original Message-
> From: pan2...@intel.com
> Sent: Monday, May 6, 2024 3:48 PM
> To: gcc-patches@gcc.gnu.org
> Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; Tamar Christina
> ; richard.guent...@gmail.com;
> hongtao@intel.com; Pan Li
> Subject: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar
> int
>
> From: Pan Li
>
> This patch would like to add the middle-end presentation for the
> saturation add. Aka set the result of add to the max when overflow.
> It will take the pattern similar as below.
>
> SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
>
> Take uint8_t as example, we will have:
>
> * SAT_ADD (1, 254) => 255.
> * SAT_ADD (1, 255) => 255.
> * SAT_ADD (2, 255) => 255.
> * SAT_ADD (255, 255) => 255.
>
> Given below example for the unsigned scalar integer uint64_t:
>
> uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> {
> return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> }
>
> Before this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> long unsigned int _1;
> _Bool _2;
> long unsigned int _3;
> long unsigned int _4;
> uint64_t _7;
> long unsigned int _10;
> __complex__ long unsigned int _11;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> _1 = REALPART_EXPR <_11>;
> _10 = IMAGPART_EXPR <_11>;
> _2 = _10 != 0;
> _3 = (long unsigned int) _2;
> _4 = -_3;
> _7 = _1 | _4;
> return _7;
> ;;succ: EXIT
>
> }
>
> After this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> uint64_t _7;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _7 = .SAT_ADD (x_5(D), y_6(D)); [tail call]
> return _7;
> ;;succ: EXIT
> }
>
> We perform the tranform during widen_mult because that the sub-expr of
> SAT_ADD will be optimized to .ADD_OVERFLOW. We need to try the .SAT_ADD
> pattern first and then .ADD_OVERFLOW, or we may never catch the pattern
> .SAT_ADD. Meanwhile, the isel pass is after widen_mult and then we
> cannot perform the .SAT_ADD pattern match as the sub-expr will be
> optmized to .ADD_OVERFLOW first.
>
> The below tests are passed for this patch:
> 1. The riscv fully regression tests.
> 2. The aarch64 fully regression tests.
> 3. The x86 bootstrap tests.
> 4. The x86 fully regression tests.
>
> PR target/51492
> PR target/112600
>
> gcc/ChangeLog:
>
> * internal-fn.cc (commutative_binary_fn_p): Add type IFN_SAT_ADD
> to the return true switch case(s).
> * internal-fn.def (SAT_ADD): Add new signed optab SAT_ADD.
> * match.pd: Add unsigned SAT_ADD match.
> * optabs.def (OPTAB_NL): Remove fixed-point limitation for us/ssadd.
> * tree-ssa-math-opts.cc (gimple_unsigned_integer_sat_add): New extern
> func decl generated in match.pd match.
> (match_saturation_arith): New func impl to match the saturation arith.
> (math_opts_dom_walker::after_dom_children): Try match saturation
> arith.
>
> Signed-off-by: Pan Li
> ---
> gcc/internal-fn.cc| 1 +
> gcc/internal-fn.def | 2 ++
> gcc/ma
RE: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned scalar int
Hi Pan,
> -Original Message-
> From: pan2...@intel.com
> Sent: Monday, May 6, 2024 3:48 PM
> To: gcc-patches@gcc.gnu.org
> Cc: juzhe.zh...@rivai.ai; kito.ch...@gmail.com; Tamar Christina
> ; richard.guent...@gmail.com;
> hongtao@intel.com; Pan Li
> Subject: [PATCH v4 1/3] Internal-fn: Support new IFN SAT_ADD for unsigned
> scalar
> int
>
> From: Pan Li
>
> This patch would like to add the middle-end presentation for the
> saturation add. Aka set the result of add to the max when overflow.
> It will take the pattern similar as below.
>
> SAT_ADD (x, y) => (x + y) | (-(TYPE)((TYPE)(x + y) < x))
>
> Take uint8_t as example, we will have:
>
> * SAT_ADD (1, 254) => 255.
> * SAT_ADD (1, 255) => 255.
> * SAT_ADD (2, 255) => 255.
> * SAT_ADD (255, 255) => 255.
>
> Given below example for the unsigned scalar integer uint64_t:
>
> uint64_t sat_add_u64 (uint64_t x, uint64_t y)
> {
> return (x + y) | (- (uint64_t)((uint64_t)(x + y) < x));
> }
>
> Before this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> long unsigned int _1;
> _Bool _2;
> long unsigned int _3;
> long unsigned int _4;
> uint64_t _7;
> long unsigned int _10;
> __complex__ long unsigned int _11;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _11 = .ADD_OVERFLOW (x_5(D), y_6(D));
> _1 = REALPART_EXPR <_11>;
> _10 = IMAGPART_EXPR <_11>;
> _2 = _10 != 0;
> _3 = (long unsigned int) _2;
> _4 = -_3;
> _7 = _1 | _4;
> return _7;
> ;;succ: EXIT
>
> }
>
> After this patch:
> uint64_t sat_add_uint64_t (uint64_t x, uint64_t y)
> {
> uint64_t _7;
>
> ;; basic block 2, loop depth 0
> ;;pred: ENTRY
> _7 = .SAT_ADD (x_5(D), y_6(D)); [tail call]
> return _7;
> ;;succ: EXIT
> }
>
> We perform the tranform during widen_mult because that the sub-expr of
> SAT_ADD will be optimized to .ADD_OVERFLOW. We need to try the .SAT_ADD
> pattern first and then .ADD_OVERFLOW, or we may never catch the pattern
> .SAT_ADD. Meanwhile, the isel pass is after widen_mult and then we
> cannot perform the .SAT_ADD pattern match as the sub-expr will be
> optmized to .ADD_OVERFLOW first.
>
> The below tests are passed for this patch:
> 1. The riscv fully regression tests.
> 2. The aarch64 fully regression tests.
> 3. The x86 bootstrap tests.
> 4. The x86 fully regression tests.
>
> PR target/51492
> PR target/112600
>
> gcc/ChangeLog:
>
> * internal-fn.cc (commutative_binary_fn_p): Add type IFN_SAT_ADD
> to the return true switch case(s).
> * internal-fn.def (SAT_ADD): Add new signed optab SAT_ADD.
> * match.pd: Add unsigned SAT_ADD match.
> * optabs.def (OPTAB_NL): Remove fixed-point limitation for us/ssadd.
> * tree-ssa-math-opts.cc (gimple_unsigned_integer_sat_add): New extern
> func decl generated in match.pd match.
> (match_saturation_arith): New func impl to match the saturation arith.
> (math_opts_dom_walker::after_dom_children): Try match saturation
> arith.
>
> Signed-off-by: Pan Li
> ---
> gcc/internal-fn.cc| 1 +
> gcc/internal-fn.def | 2 ++
> gcc/match.pd | 28
> gcc/optabs.def| 4 ++--
> gcc/tree-ssa-math-opts.cc | 46
> +++
> 5 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc
> index 0a7053c2286..73045ca8c8c 100644
> --- a/gcc/internal-fn.cc
> +++ b/gcc/internal-fn.cc
> @@ -4202,6 +4202,7 @@ commutative_binary_fn_p (internal_fn fn)
> case IFN_UBSAN_CHECK_MUL:
> case IFN_ADD_OVERFLOW:
> case IFN_MUL_OVERFLOW:
> +case IFN_SAT_ADD:
> case IFN_VEC_WIDEN_PLUS:
> case IFN_VEC_WIDEN_PLUS_LO:
> case IFN_VEC_WIDEN_PLUS_HI:
> diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
> index 848bb9dbff3..25badbb86e5 100644
> --- a/gcc/internal-fn.def
> +++ b/gcc/internal-fn.def
> @@ -275,6 +275,8 @@ DEF_INTERNAL_SIGNED_OPTAB_FN (MULHS, ECF_CONST
> | ECF_NOTHROW, first,
> DEF_INTERNAL_SIGNED_OPTAB_FN (MULHRS, ECF_CONST | ECF_NOTHROW,
> first,
> smulhrs, umulhrs, binary)
>
> +DEF_INTERNAL_SIGNED_OPTAB_FN (SAT_ADD, ECF_CONST, first, ssadd, usadd,
> binary)
> +
> DEF_INTERNAL_COND_FN (ADD, ECF_CONST, add, binary)
> DEF_INTERNAL_COND_FN (SUB, ECF_CONST, sub, binary)
> DEF_INTERNAL_COND_FN (MUL, ECF_CONST, smul, binary)
> diff --git a/gcc/match.pd b/gcc/match.pd
> index d401e7503e6..7058e4cbe29 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -3043,6 +3043,34 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> || POINTER_TYPE_P (itype))
>&& wi::eq_p (wi::to_wide (int_cst), wi::max_value (itype))
>
> +/* Unsigned Saturation Add */
> +(match (usadd_left_part @0 @1)
> + (plus:c @0 @1)
> + (if (INTEGRAL_TYPE_P (type)
> + && TYPE_UNSIGNED (TREE_TYPE (@0))
> + && types_match (type, TREE_TYPE (@0))
> + && types_match (type,
