* [PATCH] VECT: Support CALL vectorization for COND_LEN_*
@ 2023-07-24 11:46 juzhe.zhong
2023-07-24 14:33 ` Richard Biener
0 siblings, 1 reply; 9+ messages in thread
From: juzhe.zhong @ 2023-07-24 11:46 UTC (permalink / raw)
To: gcc-patches; +Cc: richard.sandiford, rguenther, Ju-Zhe Zhong
From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai>
Hi, Richard and Richi.
This patch supports CALL vectorization by COND_LEN_*.
Consider this following case:
void foo (float * __restrict a, float * __restrict b, int * __restrict cond, int n)
{
for (int i = 0; i < n; i++)
if (cond[i])
a[i] = b[i] + a[i];
}
Output of RISC-V (32-bits) gcc (trunk) (Compiler #3)
<source>:5:21: missed: couldn't vectorize loop
<source>:5:21: missed: not vectorized: control flow in loop.
ARM SVE:
...
mask__27.10_51 = vect__4.9_49 != { 0, ... };
...
vec_mask_and_55 = loop_mask_49 & mask__27.10_51;
...
vect__9.17_62 = .COND_ADD (vec_mask_and_55, vect__6.13_56, vect__8.16_60, vect__6.13_56);
For RVV, we want IR as follows:
...
_68 = .SELECT_VL (ivtmp_66, POLY_INT_CST [4, 4]);
...
mask__27.10_51 = vect__4.9_49 != { 0, ... };
...
vect__9.17_60 = .COND_LEN_ADD (mask__27.10_51, vect__6.13_55, vect__8.16_59, vect__6.13_55, _68, 0);
...
Both len and mask of COND_LEN_ADD are real not dummy.
gcc/ChangeLog:
* tree-if-conv.cc (ifcvt_can_predicate): Enable ifcvt for COND_LEN_*.
* tree-vect-stmts.cc (vectorizable_internal_function): Apply COND_LEN_*.
(vectorizable_call): Ditto.
---
gcc/tree-if-conv.cc | 7 +++-
gcc/tree-vect-stmts.cc | 84 +++++++++++++++++++++++++++++++++++++++---
2 files changed, 83 insertions(+), 8 deletions(-)
diff --git a/gcc/tree-if-conv.cc b/gcc/tree-if-conv.cc
index 799f071965e..2e17658b9ed 100644
--- a/gcc/tree-if-conv.cc
+++ b/gcc/tree-if-conv.cc
@@ -1010,8 +1010,11 @@ ifcvt_can_predicate (gimple *stmt)
if (!types_compatible_p (lhs_type, rhs_type))
return false;
internal_fn cond_fn = get_conditional_internal_fn (code);
- return (cond_fn != IFN_LAST
- && vectorized_internal_fn_supported_p (cond_fn, lhs_type));
+ internal_fn cond_len_fn = get_conditional_len_internal_fn (code);
+ return ((cond_fn != IFN_LAST
+ && vectorized_internal_fn_supported_p (cond_fn, lhs_type))
+ || (cond_len_fn != IFN_LAST
+ && vectorized_internal_fn_supported_p (cond_len_fn, lhs_type)));
}
/* Return true when STMT is if-convertible.
diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index ed28fbdced3..15401ddb682 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -1543,10 +1543,27 @@ vectorizable_internal_function (combined_fn cfn, tree fndecl,
tree vectype_out, tree vectype_in)
{
internal_fn ifn;
+ internal_fn len_ifn = IFN_LAST;
if (internal_fn_p (cfn))
- ifn = as_internal_fn (cfn);
+ {
+ ifn = as_internal_fn (cfn);
+ tree_code code = conditional_internal_fn_code (ifn);
+ len_ifn = get_conditional_len_internal_fn (code);
+ }
else
ifn = associated_internal_fn (fndecl);
+ if (len_ifn != IFN_LAST && direct_internal_fn_p (len_ifn))
+ {
+ const direct_internal_fn_info &info = direct_internal_fn (len_ifn);
+ if (info.vectorizable)
+ {
+ tree type0 = (info.type0 < 0 ? vectype_out : vectype_in);
+ tree type1 = (info.type1 < 0 ? vectype_out : vectype_in);
+ if (direct_internal_fn_supported_p (len_ifn, tree_pair (type0, type1),
+ OPTIMIZE_FOR_SPEED))
+ return len_ifn;
+ }
+ }
if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
{
const direct_internal_fn_info &info = direct_internal_fn (ifn);
@@ -3538,8 +3555,10 @@ vectorizable_call (vec_info *vinfo,
gcc_assert (ncopies >= 1);
int reduc_idx = STMT_VINFO_REDUC_IDX (stmt_info);
+ int len_index = internal_fn_len_index (ifn);
internal_fn cond_fn = get_conditional_internal_fn (ifn);
vec_loop_masks *masks = (loop_vinfo ? &LOOP_VINFO_MASKS (loop_vinfo) : NULL);
+ vec_loop_lens *lens = (loop_vinfo ? &LOOP_VINFO_LENS (loop_vinfo) : NULL);
if (!vec_stmt) /* transformation not required. */
{
if (slp_node)
@@ -3585,8 +3604,12 @@ vectorizable_call (vec_info *vinfo,
tree scalar_mask = NULL_TREE;
if (mask_opno >= 0)
scalar_mask = gimple_call_arg (stmt_info->stmt, mask_opno);
- vect_record_loop_mask (loop_vinfo, masks, nvectors,
- vectype_out, scalar_mask);
+ if (len_index >= 0)
+ vect_record_loop_len (loop_vinfo, lens, nvectors, vectype_out,
+ 1);
+ else
+ vect_record_loop_mask (loop_vinfo, masks, nvectors, vectype_out,
+ scalar_mask);
}
}
return true;
@@ -3602,8 +3625,16 @@ vectorizable_call (vec_info *vinfo,
vec_dest = vect_create_destination_var (scalar_dest, vectype_out);
bool masked_loop_p = loop_vinfo && LOOP_VINFO_FULLY_MASKED_P (loop_vinfo);
+ bool len_loop_p = loop_vinfo && LOOP_VINFO_FULLY_WITH_LENGTH_P (loop_vinfo);
unsigned int vect_nargs = nargs;
- if (masked_loop_p && reduc_idx >= 0)
+ if (len_index)
+ {
+ /* COND_ADD --> COND_LEN_ADD with 2 more args (LEN + BIAS).
+ FIXME: We don't support FMAX --> COND_LEN_FMAX yet which
+ needs 4 more args (MASK + ELSE + LEN + BIAS). */
+ vect_nargs += 2;
+ }
+ else if (masked_loop_p && reduc_idx >= 0)
{
ifn = cond_fn;
vect_nargs += 2;
@@ -3670,7 +3701,29 @@ vectorizable_call (vec_info *vinfo,
}
else
{
- if (mask_opno >= 0 && masked_loop_p)
+ if (len_index)
+ {
+ tree len, bias;
+ if (len_loop_p)
+ len
+ = vect_get_loop_len (loop_vinfo, gsi, lens,
+ ncopies, vectype_out, j, 1);
+ else
+ {
+ /* Dummy LEN. */
+ tree iv_type
+ = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
+ len
+ = build_int_cst (iv_type, TYPE_VECTOR_SUBPARTS (
+ vectype_out));
+ }
+ signed char biasval
+ = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
+ bias = build_int_cst (intQI_type_node, biasval);
+ vargs[varg++] = len;
+ vargs[varg++] = bias;
+ }
+ else if (mask_opno >= 0 && masked_loop_p)
{
unsigned int vec_num = vec_oprnds0.length ();
/* Always true for SLP. */
@@ -3718,7 +3771,26 @@ vectorizable_call (vec_info *vinfo,
if (masked_loop_p && reduc_idx >= 0)
vargs[varg++] = vargs[reduc_idx + 1];
- if (mask_opno >= 0 && masked_loop_p)
+ if (len_index)
+ {
+ tree len, bias;
+ if (len_loop_p)
+ len = vect_get_loop_len (loop_vinfo, gsi, lens, ncopies,
+ vectype_out, j, 1);
+ else
+ {
+ /* Dummy LEN. */
+ tree iv_type = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
+ len = build_int_cst (iv_type,
+ TYPE_VECTOR_SUBPARTS (vectype_out));
+ }
+ signed char biasval
+ = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
+ bias = build_int_cst (intQI_type_node, biasval);
+ vargs[varg++] = len;
+ vargs[varg++] = bias;
+ }
+ else if (mask_opno >= 0 && masked_loop_p)
{
tree mask = vect_get_loop_mask (loop_vinfo, gsi, masks, ncopies,
vectype_out, j);
--
2.36.3
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-24 11:46 [PATCH] VECT: Support CALL vectorization for COND_LEN_* juzhe.zhong
@ 2023-07-24 14:33 ` Richard Biener
2023-07-24 23:16 ` 钟居哲
0 siblings, 1 reply; 9+ messages in thread
From: Richard Biener @ 2023-07-24 14:33 UTC (permalink / raw)
To: Ju-Zhe Zhong; +Cc: gcc-patches, richard.sandiford
On Mon, 24 Jul 2023, juzhe.zhong@rivai.ai wrote:
> From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai>
>
> Hi, Richard and Richi.
>
> This patch supports CALL vectorization by COND_LEN_*.
>
> Consider this following case:
> void foo (float * __restrict a, float * __restrict b, int * __restrict cond, int n)
> {
> for (int i = 0; i < n; i++)
> if (cond[i])
> a[i] = b[i] + a[i];
> }
>
>
> Output of RISC-V (32-bits) gcc (trunk) (Compiler #3)
> <source>:5:21: missed: couldn't vectorize loop
> <source>:5:21: missed: not vectorized: control flow in loop.
>
> ARM SVE:
>
> ...
> mask__27.10_51 = vect__4.9_49 != { 0, ... };
> ...
> vec_mask_and_55 = loop_mask_49 & mask__27.10_51;
> ...
> vect__9.17_62 = .COND_ADD (vec_mask_and_55, vect__6.13_56, vect__8.16_60, vect__6.13_56);
>
> For RVV, we want IR as follows:
>
> ...
> _68 = .SELECT_VL (ivtmp_66, POLY_INT_CST [4, 4]);
> ...
> mask__27.10_51 = vect__4.9_49 != { 0, ... };
> ...
> vect__9.17_60 = .COND_LEN_ADD (mask__27.10_51, vect__6.13_55, vect__8.16_59, vect__6.13_55, _68, 0);
> ...
>
> Both len and mask of COND_LEN_ADD are real not dummy.
>
> gcc/ChangeLog:
>
> * tree-if-conv.cc (ifcvt_can_predicate): Enable ifcvt for COND_LEN_*.
> * tree-vect-stmts.cc (vectorizable_internal_function): Apply COND_LEN_*.
> (vectorizable_call): Ditto.
>
> ---
> gcc/tree-if-conv.cc | 7 +++-
> gcc/tree-vect-stmts.cc | 84 +++++++++++++++++++++++++++++++++++++++---
> 2 files changed, 83 insertions(+), 8 deletions(-)
>
> diff --git a/gcc/tree-if-conv.cc b/gcc/tree-if-conv.cc
> index 799f071965e..2e17658b9ed 100644
> --- a/gcc/tree-if-conv.cc
> +++ b/gcc/tree-if-conv.cc
> @@ -1010,8 +1010,11 @@ ifcvt_can_predicate (gimple *stmt)
> if (!types_compatible_p (lhs_type, rhs_type))
> return false;
> internal_fn cond_fn = get_conditional_internal_fn (code);
> - return (cond_fn != IFN_LAST
> - && vectorized_internal_fn_supported_p (cond_fn, lhs_type));
> + internal_fn cond_len_fn = get_conditional_len_internal_fn (code);
> + return ((cond_fn != IFN_LAST
> + && vectorized_internal_fn_supported_p (cond_fn, lhs_type))
> + || (cond_len_fn != IFN_LAST
> + && vectorized_internal_fn_supported_p (cond_len_fn, lhs_type)));
> }
>
> /* Return true when STMT is if-convertible.
> diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
> index ed28fbdced3..15401ddb682 100644
> --- a/gcc/tree-vect-stmts.cc
> +++ b/gcc/tree-vect-stmts.cc
> @@ -1543,10 +1543,27 @@ vectorizable_internal_function (combined_fn cfn, tree fndecl,
> tree vectype_out, tree vectype_in)
> {
> internal_fn ifn;
> + internal_fn len_ifn = IFN_LAST;
> if (internal_fn_p (cfn))
> - ifn = as_internal_fn (cfn);
> + {
> + ifn = as_internal_fn (cfn);
> + tree_code code = conditional_internal_fn_code (ifn);
> + len_ifn = get_conditional_len_internal_fn (code);
> + }
> else
> ifn = associated_internal_fn (fndecl);
This function doesn't seem to care about conditional vectorization
support, so why are you changing it?
> + if (len_ifn != IFN_LAST && direct_internal_fn_p (len_ifn))
> + {
> + const direct_internal_fn_info &info = direct_internal_fn (len_ifn);
> + if (info.vectorizable)
> + {
> + tree type0 = (info.type0 < 0 ? vectype_out : vectype_in);
> + tree type1 = (info.type1 < 0 ? vectype_out : vectype_in);
> + if (direct_internal_fn_supported_p (len_ifn, tree_pair (type0, type1),
> + OPTIMIZE_FOR_SPEED))
> + return len_ifn;
> + }
> + }
> if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
> {
> const direct_internal_fn_info &info = direct_internal_fn (ifn);
> @@ -3538,8 +3555,10 @@ vectorizable_call (vec_info *vinfo,
> gcc_assert (ncopies >= 1);
>
> int reduc_idx = STMT_VINFO_REDUC_IDX (stmt_info);
> + int len_index = internal_fn_len_index (ifn);
Note traditionally non-LEN fns would return -1 here, so ...
> internal_fn cond_fn = get_conditional_internal_fn (ifn);
> vec_loop_masks *masks = (loop_vinfo ? &LOOP_VINFO_MASKS (loop_vinfo) : NULL);
> + vec_loop_lens *lens = (loop_vinfo ? &LOOP_VINFO_LENS (loop_vinfo) : NULL);
> if (!vec_stmt) /* transformation not required. */
> {
> if (slp_node)
> @@ -3585,8 +3604,12 @@ vectorizable_call (vec_info *vinfo,
instead there's code here that checks for the .COND_xxx case so you should
ament it for the len case as well?
> tree scalar_mask = NULL_TREE;
> if (mask_opno >= 0)
> scalar_mask = gimple_call_arg (stmt_info->stmt, mask_opno);
> - vect_record_loop_mask (loop_vinfo, masks, nvectors,
> - vectype_out, scalar_mask);
> + if (len_index >= 0)
> + vect_record_loop_len (loop_vinfo, lens, nvectors, vectype_out,
> + 1);
> + else
> + vect_record_loop_mask (loop_vinfo, masks, nvectors, vectype_out,
> + scalar_mask);
> }
> }
> return true;
> @@ -3602,8 +3625,16 @@ vectorizable_call (vec_info *vinfo,
> vec_dest = vect_create_destination_var (scalar_dest, vectype_out);
>
> bool masked_loop_p = loop_vinfo && LOOP_VINFO_FULLY_MASKED_P (loop_vinfo);
> + bool len_loop_p = loop_vinfo && LOOP_VINFO_FULLY_WITH_LENGTH_P (loop_vinfo);
> unsigned int vect_nargs = nargs;
> - if (masked_loop_p && reduc_idx >= 0)
> + if (len_index)
what about reduc_indx? Why check len_indes and not len_loop_p?
... checking len_index is going to be true for -1, you probably would
want len_index != -1 then?
> + {
> + /* COND_ADD --> COND_LEN_ADD with 2 more args (LEN + BIAS).
> + FIXME: We don't support FMAX --> COND_LEN_FMAX yet which
> + needs 4 more args (MASK + ELSE + LEN + BIAS). */
> + vect_nargs += 2;
> + }
> + else if (masked_loop_p && reduc_idx >= 0)
> {
> ifn = cond_fn;
> vect_nargs += 2;
> @@ -3670,7 +3701,29 @@ vectorizable_call (vec_info *vinfo,
> }
> else
> {
> - if (mask_opno >= 0 && masked_loop_p)
> + if (len_index)
see above
> + {
> + tree len, bias;
> + if (len_loop_p)
> + len
> + = vect_get_loop_len (loop_vinfo, gsi, lens,
> + ncopies, vectype_out, j, 1);
> + else
> + {
> + /* Dummy LEN. */
> + tree iv_type
> + = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
> + len
> + = build_int_cst (iv_type, TYPE_VECTOR_SUBPARTS (
> + vectype_out));
> + }
> + signed char biasval
> + = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
> + bias = build_int_cst (intQI_type_node, biasval);
> + vargs[varg++] = len;
> + vargs[varg++] = bias;
> + }
> + else if (mask_opno >= 0 && masked_loop_p)
> {
> unsigned int vec_num = vec_oprnds0.length ();
> /* Always true for SLP. */
> @@ -3718,7 +3771,26 @@ vectorizable_call (vec_info *vinfo,
> if (masked_loop_p && reduc_idx >= 0)
> vargs[varg++] = vargs[reduc_idx + 1];
>
> - if (mask_opno >= 0 && masked_loop_p)
> + if (len_index)
> + {
> + tree len, bias;
> + if (len_loop_p)
> + len = vect_get_loop_len (loop_vinfo, gsi, lens, ncopies,
> + vectype_out, j, 1);
> + else
> + {
> + /* Dummy LEN. */
> + tree iv_type = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
> + len = build_int_cst (iv_type,
> + TYPE_VECTOR_SUBPARTS (vectype_out));
> + }
> + signed char biasval
> + = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
> + bias = build_int_cst (intQI_type_node, biasval);
> + vargs[varg++] = len;
> + vargs[varg++] = bias;
You are not actually using len_index to place the arguments. See
how mask_opno is used.
You are producing patches too quickly, please double-check what you did
before posting for review.
Thanks,
Richard.
> + }
> + else if (mask_opno >= 0 && masked_loop_p)
> {
> tree mask = vect_get_loop_mask (loop_vinfo, gsi, masks, ncopies,
> vectype_out, j);
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-24 14:33 ` Richard Biener
@ 2023-07-24 23:16 ` 钟居哲
2023-07-25 9:41 ` Richard Sandiford
0 siblings, 1 reply; 9+ messages in thread
From: 钟居哲 @ 2023-07-24 23:16 UTC (permalink / raw)
To: rguenther; +Cc: gcc-patches, richard.sandiford
[-- Attachment #1: Type: text/plain, Size: 12384 bytes --]
Hi, Richi. Thank you so much for review.
>> This function doesn't seem to care about conditional vectorization
>> support, so why are you changing it?
I debug and analyze the code here:
Breakpoint 1, vectorizable_call (vinfo=0x3d358d0, stmt_info=0x3dcc820, gsi=0x0, vec_stmt=0x0, slp_node=0x0, cost_vec=0x7fffffffc668) at ../../../riscv-gcc/gcc/tree-vect-stmts.cc:3485
3485 ifn = vectorizable_internal_function (cfn, callee, vectype_out,
(gdb) p cfn
$1 = CFN_COND_ADD
(gdb) call print_gimple_stmt(stdout,stmt,0,0)
_9 = .COND_ADD (_27, _6, _8, _6);
When target like RISC-V didnt' support COND_* (we only support COND_LEN_*, no support COND_*),
ifn will be IFN_LAST.
Also, the following code doesn't modify ifn until
"internal_fn cond_fn = get_conditional_internal_fn (ifn);"
When ifn == IFN_LAST, cond_fn will IFN_LAST too.
So, I extend "vectorizable_internal_function" to return COND_LEN_*.
Am I going into wrong direction on debug && analysis.
>> what about reduc_indx? Why check len_indes and not len_loop_p?
>> Note traditionally non-LEN fns would return -1 here, so ...
>> instead there's code here that checks for the .COND_xxx case so you should
>> ament it for the len case as well?
>> You are not actually using len_index to place the arguments. See
>> how mask_opno is used.
I understand this patch codes look quite strange not natural.
Give me some time to share the story why I am doing this:
1. At the beginning, I want to write the codes naturally and very similiar with the current codes.
So it's natural to write the codes like this:
if (mask_opno >= 0 && len_loop_p) {
tree len = vect_get_loop_len
tree bias = ....
}
However, we have the following case:
void foo1 (float * __restrict a, float * __restrict b, int * __restrict cond, int n)
{
for (int i = 0; i < 8; i++)
if (cond[i])
a[i] = b[i] + a[i];
}
Note here "i<8" means niters = 8 and compile with known VF (fixed-length vector) to vectorize the codes.
Then len_loop_p will be false.
If I don't handle case, then the code will generate the IR:
COND_LEN_ADD (maks, op1, op2, op3)....
Missing LEN && BIAS argument which cause ICE.
2. So I use "int len_index = internal_fn_len_index (ifn);",
ifn is supported as COND_LEN_*, the len_index >= 0, otherwise, it will be -1.
So I prepare LEN && BIAS arguments according to len_index.
So I change the code into:
if (len_index >= 0) {
tree len = vect_get_loop_len
tree bias = ....
}
3. Overall, I want to normalize COND_* into COND_LEN_*, when loop_len_p is false, then I create a dummy LEN for it.
It make the codes strange.
4. I have another approach/prepared patch which makes codes more natural:
Enable COND_xxxx in RISC-V port, then keep "tree-vect-ifcvt.cc" unchange,
and "vectorizable_internal_function" unchange.
And simpily write the codes like this:
if (mask_opno >= 0 && len_loop_p) {
tree len = vect_get_loop_len
tree bias = ....
}
and when len_loop_p is true, I change to use "COND_LEN_xxx", otherwise reuse original flow.
Are you suggesting me doing this? Meaning enable COND_xxx (The patterns are duplicate I think if we have COND_LEN_xxx) in RISC-V port ?
>> You are producing patches too quickly, please double-check what you did
>> before posting for review.
I am so sorry this patch codes look quite strange and confusing.
I actually consider it for some time
(I have 2 prepared patches, this one which is not natural, the other only add a very few codes and look natural and more acceptable ),
and compare them (the other one I need to support COND_xxx in RISC-V port).
Maybe it's better enable COND_xxx in RISC-V port so that the codes in middle-end look much more reasonable ?
I think maybe next time I should ask you first about the solution before I send the patch
Looking forward your suggestions.
Thanks.
juzhe.zhong@rivai.ai
From: Richard Biener
Date: 2023-07-24 22:33
To: Ju-Zhe Zhong
CC: gcc-patches; richard.sandiford
Subject: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
On Mon, 24 Jul 2023, juzhe.zhong@rivai.ai wrote:
> From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai>
>
> Hi, Richard and Richi.
>
> This patch supports CALL vectorization by COND_LEN_*.
>
> Consider this following case:
> void foo (float * __restrict a, float * __restrict b, int * __restrict cond, int n)
> {
> for (int i = 0; i < n; i++)
> if (cond[i])
> a[i] = b[i] + a[i];
> }
>
>
> Output of RISC-V (32-bits) gcc (trunk) (Compiler #3)
> <source>:5:21: missed: couldn't vectorize loop
> <source>:5:21: missed: not vectorized: control flow in loop.
>
> ARM SVE:
>
> ...
> mask__27.10_51 = vect__4.9_49 != { 0, ... };
> ...
> vec_mask_and_55 = loop_mask_49 & mask__27.10_51;
> ...
> vect__9.17_62 = .COND_ADD (vec_mask_and_55, vect__6.13_56, vect__8.16_60, vect__6.13_56);
>
> For RVV, we want IR as follows:
>
> ...
> _68 = .SELECT_VL (ivtmp_66, POLY_INT_CST [4, 4]);
> ...
> mask__27.10_51 = vect__4.9_49 != { 0, ... };
> ...
> vect__9.17_60 = .COND_LEN_ADD (mask__27.10_51, vect__6.13_55, vect__8.16_59, vect__6.13_55, _68, 0);
> ...
>
> Both len and mask of COND_LEN_ADD are real not dummy.
>
> gcc/ChangeLog:
>
> * tree-if-conv.cc (ifcvt_can_predicate): Enable ifcvt for COND_LEN_*.
> * tree-vect-stmts.cc (vectorizable_internal_function): Apply COND_LEN_*.
> (vectorizable_call): Ditto.
>
> ---
> gcc/tree-if-conv.cc | 7 +++-
> gcc/tree-vect-stmts.cc | 84 +++++++++++++++++++++++++++++++++++++++---
> 2 files changed, 83 insertions(+), 8 deletions(-)
>
> diff --git a/gcc/tree-if-conv.cc b/gcc/tree-if-conv.cc
> index 799f071965e..2e17658b9ed 100644
> --- a/gcc/tree-if-conv.cc
> +++ b/gcc/tree-if-conv.cc
> @@ -1010,8 +1010,11 @@ ifcvt_can_predicate (gimple *stmt)
> if (!types_compatible_p (lhs_type, rhs_type))
> return false;
> internal_fn cond_fn = get_conditional_internal_fn (code);
> - return (cond_fn != IFN_LAST
> - && vectorized_internal_fn_supported_p (cond_fn, lhs_type));
> + internal_fn cond_len_fn = get_conditional_len_internal_fn (code);
> + return ((cond_fn != IFN_LAST
> + && vectorized_internal_fn_supported_p (cond_fn, lhs_type))
> + || (cond_len_fn != IFN_LAST
> + && vectorized_internal_fn_supported_p (cond_len_fn, lhs_type)));
> }
>
> /* Return true when STMT is if-convertible.
> diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
> index ed28fbdced3..15401ddb682 100644
> --- a/gcc/tree-vect-stmts.cc
> +++ b/gcc/tree-vect-stmts.cc
> @@ -1543,10 +1543,27 @@ vectorizable_internal_function (combined_fn cfn, tree fndecl,
> tree vectype_out, tree vectype_in)
> {
> internal_fn ifn;
> + internal_fn len_ifn = IFN_LAST;
> if (internal_fn_p (cfn))
> - ifn = as_internal_fn (cfn);
> + {
> + ifn = as_internal_fn (cfn);
> + tree_code code = conditional_internal_fn_code (ifn);
> + len_ifn = get_conditional_len_internal_fn (code);
> + }
> else
> ifn = associated_internal_fn (fndecl);
This function doesn't seem to care about conditional vectorization
support, so why are you changing it?
> + if (len_ifn != IFN_LAST && direct_internal_fn_p (len_ifn))
> + {
> + const direct_internal_fn_info &info = direct_internal_fn (len_ifn);
> + if (info.vectorizable)
> + {
> + tree type0 = (info.type0 < 0 ? vectype_out : vectype_in);
> + tree type1 = (info.type1 < 0 ? vectype_out : vectype_in);
> + if (direct_internal_fn_supported_p (len_ifn, tree_pair (type0, type1),
> + OPTIMIZE_FOR_SPEED))
> + return len_ifn;
> + }
> + }
> if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
> {
> const direct_internal_fn_info &info = direct_internal_fn (ifn);
> @@ -3538,8 +3555,10 @@ vectorizable_call (vec_info *vinfo,
> gcc_assert (ncopies >= 1);
>
> int reduc_idx = STMT_VINFO_REDUC_IDX (stmt_info);
> + int len_index = internal_fn_len_index (ifn);
Note traditionally non-LEN fns would return -1 here, so ...
> internal_fn cond_fn = get_conditional_internal_fn (ifn);
> vec_loop_masks *masks = (loop_vinfo ? &LOOP_VINFO_MASKS (loop_vinfo) : NULL);
> + vec_loop_lens *lens = (loop_vinfo ? &LOOP_VINFO_LENS (loop_vinfo) : NULL);
> if (!vec_stmt) /* transformation not required. */
> {
> if (slp_node)
> @@ -3585,8 +3604,12 @@ vectorizable_call (vec_info *vinfo,
instead there's code here that checks for the .COND_xxx case so you should
ament it for the len case as well?
> tree scalar_mask = NULL_TREE;
> if (mask_opno >= 0)
> scalar_mask = gimple_call_arg (stmt_info->stmt, mask_opno);
> - vect_record_loop_mask (loop_vinfo, masks, nvectors,
> - vectype_out, scalar_mask);
> + if (len_index >= 0)
> + vect_record_loop_len (loop_vinfo, lens, nvectors, vectype_out,
> + 1);
> + else
> + vect_record_loop_mask (loop_vinfo, masks, nvectors, vectype_out,
> + scalar_mask);
> }
> }
> return true;
> @@ -3602,8 +3625,16 @@ vectorizable_call (vec_info *vinfo,
> vec_dest = vect_create_destination_var (scalar_dest, vectype_out);
>
> bool masked_loop_p = loop_vinfo && LOOP_VINFO_FULLY_MASKED_P (loop_vinfo);
> + bool len_loop_p = loop_vinfo && LOOP_VINFO_FULLY_WITH_LENGTH_P (loop_vinfo);
> unsigned int vect_nargs = nargs;
> - if (masked_loop_p && reduc_idx >= 0)
> + if (len_index)
what about reduc_indx? Why check len_indes and not len_loop_p?
... checking len_index is going to be true for -1, you probably would
want len_index != -1 then?
> + {
> + /* COND_ADD --> COND_LEN_ADD with 2 more args (LEN + BIAS).
> + FIXME: We don't support FMAX --> COND_LEN_FMAX yet which
> + needs 4 more args (MASK + ELSE + LEN + BIAS). */
> + vect_nargs += 2;
> + }
> + else if (masked_loop_p && reduc_idx >= 0)
> {
> ifn = cond_fn;
> vect_nargs += 2;
> @@ -3670,7 +3701,29 @@ vectorizable_call (vec_info *vinfo,
> }
> else
> {
> - if (mask_opno >= 0 && masked_loop_p)
> + if (len_index)
see above
> + {
> + tree len, bias;
> + if (len_loop_p)
> + len
> + = vect_get_loop_len (loop_vinfo, gsi, lens,
> + ncopies, vectype_out, j, 1);
> + else
> + {
> + /* Dummy LEN. */
> + tree iv_type
> + = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
> + len
> + = build_int_cst (iv_type, TYPE_VECTOR_SUBPARTS (
> + vectype_out));
> + }
> + signed char biasval
> + = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
> + bias = build_int_cst (intQI_type_node, biasval);
> + vargs[varg++] = len;
> + vargs[varg++] = bias;
> + }
> + else if (mask_opno >= 0 && masked_loop_p)
> {
> unsigned int vec_num = vec_oprnds0.length ();
> /* Always true for SLP. */
> @@ -3718,7 +3771,26 @@ vectorizable_call (vec_info *vinfo,
> if (masked_loop_p && reduc_idx >= 0)
> vargs[varg++] = vargs[reduc_idx + 1];
>
> - if (mask_opno >= 0 && masked_loop_p)
> + if (len_index)
> + {
> + tree len, bias;
> + if (len_loop_p)
> + len = vect_get_loop_len (loop_vinfo, gsi, lens, ncopies,
> + vectype_out, j, 1);
> + else
> + {
> + /* Dummy LEN. */
> + tree iv_type = LOOP_VINFO_RGROUP_IV_TYPE (loop_vinfo);
> + len = build_int_cst (iv_type,
> + TYPE_VECTOR_SUBPARTS (vectype_out));
> + }
> + signed char biasval
> + = LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS (loop_vinfo);
> + bias = build_int_cst (intQI_type_node, biasval);
> + vargs[varg++] = len;
> + vargs[varg++] = bias;
You are not actually using len_index to place the arguments. See
how mask_opno is used.
You are producing patches too quickly, please double-check what you did
before posting for review.
Thanks,
Richard.
> + }
> + else if (mask_opno >= 0 && masked_loop_p)
> {
> tree mask = vect_get_loop_mask (loop_vinfo, gsi, masks, ncopies,
> vectype_out, j);
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-24 23:16 ` 钟居哲
@ 2023-07-25 9:41 ` Richard Sandiford
2023-07-25 10:17 ` juzhe.zhong
2023-07-31 9:30 ` Richard Biener
0 siblings, 2 replies; 9+ messages in thread
From: Richard Sandiford @ 2023-07-25 9:41 UTC (permalink / raw)
To: 钟居哲; +Cc: rguenther, gcc-patches
钟居哲 <juzhe.zhong@rivai.ai> writes:
> Hi, Richi. Thank you so much for review.
>
>>> This function doesn't seem to care about conditional vectorization
>>> support, so why are you changing it?
>
> I debug and analyze the code here:
>
> Breakpoint 1, vectorizable_call (vinfo=0x3d358d0, stmt_info=0x3dcc820, gsi=0x0, vec_stmt=0x0, slp_node=0x0, cost_vec=0x7fffffffc668) at ../../../riscv-gcc/gcc/tree-vect-stmts.cc:3485
> 3485 ifn = vectorizable_internal_function (cfn, callee, vectype_out,
> (gdb) p cfn
> $1 = CFN_COND_ADD
> (gdb) call print_gimple_stmt(stdout,stmt,0,0)
> _9 = .COND_ADD (_27, _6, _8, _6);
>
> When target like RISC-V didnt' support COND_* (we only support COND_LEN_*, no support COND_*),
> ifn will be IFN_LAST.
> Also, the following code doesn't modify ifn until
> "internal_fn cond_fn = get_conditional_internal_fn (ifn);"
> When ifn == IFN_LAST, cond_fn will IFN_LAST too.
>
> So, I extend "vectorizable_internal_function" to return COND_LEN_*.
>
> Am I going into wrong direction on debug && analysis.
The main difference between IFN_COND_ADD and IFN_COND_LEN_ADD is that
IFN_COND_ADD makes logical sense for scalars, whereas IFN_COND_LEN_ADD
only makes sense for vectors. So I think if-conversion has to create
IFN_COND_ADD rather than IFN_COND_LEN_ADD even for targets that only
support IFN_COND_LEN_ADD. (Which is what the patch does.)
IFN_COND_LEN_ADD is really a generalisation of IFN_COND_ADD. In a
sense, every target that supports IFN_COND_LEN_ADD also supports
IFN_COND_ADD. All we need is two extra arguments. And the patch
does seem to take that approach (by adding dummy length arguments).
So I think there are at least four ways we could go:
(1) RVV implements cond_* optabs as expanders. RVV therefore supports
both IFN_COND_ADD and IFN_COND_LEN_ADD. No dummy length arguments
are needed at the gimple level.
(2) Target-independent code automatically provides cond_* optabs
based on cond_len_* optabs. Otherwise the same as (1).
(3) A gimple pass lowers IFN_COND_ADD to IFN_COND_LEN_ADD on targets
that need it. Could be vec lowering or isel.
(4) The vectoriser maintains the distinction between IFN_COND_ADD and
IFN_COND_LEN_ADD from the outset. It adds dummy length arguments
where necessary.
The patch is going for (4). But I think we should at least consider
whether any of the other alternatives make sense.
If we do go for (4), I think the get_conditional_len_internal_fn
is in the wrong place. It should be applied:
internal_fn ifn;
if (internal_fn_p (cfn))
ifn = as_internal_fn (cfn);
else
ifn = associated_internal_fn (fndecl);
if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
{
// After this point
I don't think we should assume that every IFN_COND_* has an associated
tree code. It should be possible to create IFN_COND_*s from unconditional
internal functions too. So rather than use:
tree_code code = conditional_internal_fn_code (ifn);
len_ifn = get_conditional_len_internal_fn (code);
I think we should have an internal-fn helper that returns IFN_COND_LEN_*
for a given IFN_COND_*. It could handle IFN_MASK_LOAD -> IFN_MASK_LEN_LOAD
etc. too.
It would help if we combined the COND_* and COND_LEN_* definitions.
For example:
DEF_INTERNAL_OPTAB_FN (COND_ADD, ECF_CONST, cond_add, cond_binary)
DEF_INTERNAL_OPTAB_FN (COND_LEN_ADD, ECF_CONST, cond_len_add, cond_len_binary)
could become:
DEF_INTERNAL_COND_FN (ADD, ECF_CONST, add, binary)
that expands to the COND_ADD and COND_LEN_ADD definitions. This would
help to keep the definitions in sync and would make it eaiser to do a
mapping between COND_* and COND_LEN_*.
Thanks,
Richard
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-25 9:41 ` Richard Sandiford
@ 2023-07-25 10:17 ` juzhe.zhong
2023-07-25 10:21 ` Richard Sandiford
2023-07-31 9:30 ` Richard Biener
1 sibling, 1 reply; 9+ messages in thread
From: juzhe.zhong @ 2023-07-25 10:17 UTC (permalink / raw)
To: richard.sandiford; +Cc: rguenther, gcc-patches
[-- Attachment #1: Type: text/plain, Size: 4396 bytes --]
Thanks Richard.
Do you suggest we should add a macro like this first:
#ifndef DEF_INTERNAL_COND_FN
#define DEF_INTERNAL_COND_FN(NAME, FLAGS, OPTAB, TYPE) \
DEF_INTERNAL_OPTAB_FN (COND_##NAME, FLAGS, cond_##optab, cond_##TYPE)
DEF_INTERNAL_OPTAB_FN (COND_LEN_##NAME, FLAGS, cond_len_##optab, cond_len_##TYPE)
#endif
If yes, maybe I should first do this in a single patch first?
juzhe.zhong@rivai.ai
From: Richard Sandiford
Date: 2023-07-25 17:41
To: 钟居哲
CC: rguenther; gcc-patches
Subject: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
钟居哲 <juzhe.zhong@rivai.ai> writes:
> Hi, Richi. Thank you so much for review.
>
>>> This function doesn't seem to care about conditional vectorization
>>> support, so why are you changing it?
>
> I debug and analyze the code here:
>
> Breakpoint 1, vectorizable_call (vinfo=0x3d358d0, stmt_info=0x3dcc820, gsi=0x0, vec_stmt=0x0, slp_node=0x0, cost_vec=0x7fffffffc668) at ../../../riscv-gcc/gcc/tree-vect-stmts.cc:3485
> 3485 ifn = vectorizable_internal_function (cfn, callee, vectype_out,
> (gdb) p cfn
> $1 = CFN_COND_ADD
> (gdb) call print_gimple_stmt(stdout,stmt,0,0)
> _9 = .COND_ADD (_27, _6, _8, _6);
>
> When target like RISC-V didnt' support COND_* (we only support COND_LEN_*, no support COND_*),
> ifn will be IFN_LAST.
> Also, the following code doesn't modify ifn until
> "internal_fn cond_fn = get_conditional_internal_fn (ifn);"
> When ifn == IFN_LAST, cond_fn will IFN_LAST too.
>
> So, I extend "vectorizable_internal_function" to return COND_LEN_*.
>
> Am I going into wrong direction on debug && analysis.
The main difference between IFN_COND_ADD and IFN_COND_LEN_ADD is that
IFN_COND_ADD makes logical sense for scalars, whereas IFN_COND_LEN_ADD
only makes sense for vectors. So I think if-conversion has to create
IFN_COND_ADD rather than IFN_COND_LEN_ADD even for targets that only
support IFN_COND_LEN_ADD. (Which is what the patch does.)
IFN_COND_LEN_ADD is really a generalisation of IFN_COND_ADD. In a
sense, every target that supports IFN_COND_LEN_ADD also supports
IFN_COND_ADD. All we need is two extra arguments. And the patch
does seem to take that approach (by adding dummy length arguments).
So I think there are at least four ways we could go:
(1) RVV implements cond_* optabs as expanders. RVV therefore supports
both IFN_COND_ADD and IFN_COND_LEN_ADD. No dummy length arguments
are needed at the gimple level.
(2) Target-independent code automatically provides cond_* optabs
based on cond_len_* optabs. Otherwise the same as (1).
(3) A gimple pass lowers IFN_COND_ADD to IFN_COND_LEN_ADD on targets
that need it. Could be vec lowering or isel.
(4) The vectoriser maintains the distinction between IFN_COND_ADD and
IFN_COND_LEN_ADD from the outset. It adds dummy length arguments
where necessary.
The patch is going for (4). But I think we should at least consider
whether any of the other alternatives make sense.
If we do go for (4), I think the get_conditional_len_internal_fn
is in the wrong place. It should be applied:
internal_fn ifn;
if (internal_fn_p (cfn))
ifn = as_internal_fn (cfn);
else
ifn = associated_internal_fn (fndecl);
if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
{
// After this point
I don't think we should assume that every IFN_COND_* has an associated
tree code. It should be possible to create IFN_COND_*s from unconditional
internal functions too. So rather than use:
tree_code code = conditional_internal_fn_code (ifn);
len_ifn = get_conditional_len_internal_fn (code);
I think we should have an internal-fn helper that returns IFN_COND_LEN_*
for a given IFN_COND_*. It could handle IFN_MASK_LOAD -> IFN_MASK_LEN_LOAD
etc. too.
It would help if we combined the COND_* and COND_LEN_* definitions.
For example:
DEF_INTERNAL_OPTAB_FN (COND_ADD, ECF_CONST, cond_add, cond_binary)
DEF_INTERNAL_OPTAB_FN (COND_LEN_ADD, ECF_CONST, cond_len_add, cond_len_binary)
could become:
DEF_INTERNAL_COND_FN (ADD, ECF_CONST, add, binary)
that expands to the COND_ADD and COND_LEN_ADD definitions. This would
help to keep the definitions in sync and would make it eaiser to do a
mapping between COND_* and COND_LEN_*.
Thanks,
Richard
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-25 10:17 ` juzhe.zhong
@ 2023-07-25 10:21 ` Richard Sandiford
2023-07-25 11:31 ` juzhe.zhong
0 siblings, 1 reply; 9+ messages in thread
From: Richard Sandiford @ 2023-07-25 10:21 UTC (permalink / raw)
To: juzhe.zhong; +Cc: rguenther, gcc-patches
"juzhe.zhong@rivai.ai" <juzhe.zhong@rivai.ai> writes:
> Thanks Richard.
>
> Do you suggest we should add a macro like this first:
>
> #ifndef DEF_INTERNAL_COND_FN
> #define DEF_INTERNAL_COND_FN(NAME, FLAGS, OPTAB, TYPE) \
> DEF_INTERNAL_OPTAB_FN (COND_##NAME, FLAGS, cond_##optab, cond_##TYPE)
> DEF_INTERNAL_OPTAB_FN (COND_LEN_##NAME, FLAGS, cond_len_##optab, cond_len_##TYPE)
> #endif
Yeah. (Think there's a missing backslash though.)
> If yes, maybe I should first do this in a single patch first?
Yeah, doing it as a separate patch sounds good.
Richard
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-25 10:21 ` Richard Sandiford
@ 2023-07-25 11:31 ` juzhe.zhong
2023-07-25 12:18 ` Richard Sandiford
0 siblings, 1 reply; 9+ messages in thread
From: juzhe.zhong @ 2023-07-25 11:31 UTC (permalink / raw)
To: richard.sandiford; +Cc: rguenther, gcc-patches
[-- Attachment #1: Type: text/plain, Size: 1100 bytes --]
Hi, Richard.
>> I think we should have an internal-fn helper that returns IFN_COND_LEN_*
>> for a given IFN_COND_*. It could handle IFN_MASK_LOAD -> IFN_MASK_LEN_LOAD
>> etc. too.
Could you name this helper function for me? Does it call "get_conditional_len_internal_fn_for_conditional_fn" ?
Thanks.
juzhe.zhong@rivai.ai
From: Richard Sandiford
Date: 2023-07-25 18:21
To: juzhe.zhong\@rivai.ai
CC: rguenther; gcc-patches
Subject: Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
"juzhe.zhong@rivai.ai" <juzhe.zhong@rivai.ai> writes:
> Thanks Richard.
>
> Do you suggest we should add a macro like this first:
>
> #ifndef DEF_INTERNAL_COND_FN
> #define DEF_INTERNAL_COND_FN(NAME, FLAGS, OPTAB, TYPE) \
> DEF_INTERNAL_OPTAB_FN (COND_##NAME, FLAGS, cond_##optab, cond_##TYPE)
> DEF_INTERNAL_OPTAB_FN (COND_LEN_##NAME, FLAGS, cond_len_##optab, cond_len_##TYPE)
> #endif
Yeah. (Think there's a missing backslash though.)
> If yes, maybe I should first do this in a single patch first?
Yeah, doing it as a separate patch sounds good.
Richard
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-25 11:31 ` juzhe.zhong
@ 2023-07-25 12:18 ` Richard Sandiford
0 siblings, 0 replies; 9+ messages in thread
From: Richard Sandiford @ 2023-07-25 12:18 UTC (permalink / raw)
To: juzhe.zhong; +Cc: rguenther, gcc-patches
"juzhe.zhong@rivai.ai" <juzhe.zhong@rivai.ai> writes:
> Hi, Richard.
>>> I think we should have an internal-fn helper that returns IFN_COND_LEN_*
>>> for a given IFN_COND_*. It could handle IFN_MASK_LOAD -> IFN_MASK_LEN_LOAD
>>> etc. too.
> Could you name this helper function for me? Does it call "get_conditional_len_internal_fn_for_conditional_fn" ?
How about get_len_internal_fn?
/* If there exists an internal function like IFN that operates on vectors,
but with additional length and bias parameters, return the internal_fn
for that function, otherwise return IFN_LAST. */
Thanks,
Richard
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] VECT: Support CALL vectorization for COND_LEN_*
2023-07-25 9:41 ` Richard Sandiford
2023-07-25 10:17 ` juzhe.zhong
@ 2023-07-31 9:30 ` Richard Biener
1 sibling, 0 replies; 9+ messages in thread
From: Richard Biener @ 2023-07-31 9:30 UTC (permalink / raw)
To: Richard Sandiford; +Cc: 钟居哲, gcc-patches
On Tue, 25 Jul 2023, Richard Sandiford wrote:
> ??? <juzhe.zhong@rivai.ai> writes:
> > Hi, Richi. Thank you so much for review.
> >
> >>> This function doesn't seem to care about conditional vectorization
> >>> support, so why are you changing it?
> >
> > I debug and analyze the code here:
> >
> > Breakpoint 1, vectorizable_call (vinfo=0x3d358d0, stmt_info=0x3dcc820, gsi=0x0, vec_stmt=0x0, slp_node=0x0, cost_vec=0x7fffffffc668) at ../../../riscv-gcc/gcc/tree-vect-stmts.cc:3485
> > 3485 ifn = vectorizable_internal_function (cfn, callee, vectype_out,
> > (gdb) p cfn
> > $1 = CFN_COND_ADD
> > (gdb) call print_gimple_stmt(stdout,stmt,0,0)
> > _9 = .COND_ADD (_27, _6, _8, _6);
> >
> > When target like RISC-V didnt' support COND_* (we only support COND_LEN_*, no support COND_*),
> > ifn will be IFN_LAST.
> > Also, the following code doesn't modify ifn until
> > "internal_fn cond_fn = get_conditional_internal_fn (ifn);"
> > When ifn == IFN_LAST, cond_fn will IFN_LAST too.
> >
> > So, I extend "vectorizable_internal_function" to return COND_LEN_*.
> >
> > Am I going into wrong direction on debug && analysis.
>
> The main difference between IFN_COND_ADD and IFN_COND_LEN_ADD is that
> IFN_COND_ADD makes logical sense for scalars, whereas IFN_COND_LEN_ADD
> only makes sense for vectors. So I think if-conversion has to create
> IFN_COND_ADD rather than IFN_COND_LEN_ADD even for targets that only
> support IFN_COND_LEN_ADD. (Which is what the patch does.)
>
> IFN_COND_LEN_ADD is really a generalisation of IFN_COND_ADD. In a
> sense, every target that supports IFN_COND_LEN_ADD also supports
> IFN_COND_ADD. All we need is two extra arguments. And the patch
> does seem to take that approach (by adding dummy length arguments).
>
> So I think there are at least four ways we could go:
>
> (1) RVV implements cond_* optabs as expanders. RVV therefore supports
> both IFN_COND_ADD and IFN_COND_LEN_ADD. No dummy length arguments
> are needed at the gimple level.
>
> (2) Target-independent code automatically provides cond_* optabs
> based on cond_len_* optabs. Otherwise the same as (1).
>
> (3) A gimple pass lowers IFN_COND_ADD to IFN_COND_LEN_ADD on targets
> that need it. Could be vec lowering or isel.
>
> (4) The vectoriser maintains the distinction between IFN_COND_ADD and
> IFN_COND_LEN_ADD from the outset. It adds dummy length arguments
> where necessary.
>
> The patch is going for (4). But I think we should at least consider
> whether any of the other alternatives make sense.
I think only (1) and (4) make sense. The vectorizer would need to
check for IFN_COND_LEN_ADD or IFN_COND_ADD support anyway even
when only emitting IFN_COND_ADD. Since we've already gone half-way
then we can as well do (4). That also possibly simplifies N targets
as opposed to just the vectorizer. So my preference would be (4),
but I'm also fine with (1).
Richard.
> If we do go for (4), I think the get_conditional_len_internal_fn
> is in the wrong place. It should be applied:
>
> internal_fn ifn;
> if (internal_fn_p (cfn))
> ifn = as_internal_fn (cfn);
> else
> ifn = associated_internal_fn (fndecl);
> if (ifn != IFN_LAST && direct_internal_fn_p (ifn))
> {
> // After this point
>
> I don't think we should assume that every IFN_COND_* has an associated
> tree code. It should be possible to create IFN_COND_*s from unconditional
> internal functions too. So rather than use:
>
> tree_code code = conditional_internal_fn_code (ifn);
> len_ifn = get_conditional_len_internal_fn (code);
>
> I think we should have an internal-fn helper that returns IFN_COND_LEN_*
> for a given IFN_COND_*. It could handle IFN_MASK_LOAD -> IFN_MASK_LEN_LOAD
> etc. too.
>
> It would help if we combined the COND_* and COND_LEN_* definitions.
> For example:
>
> DEF_INTERNAL_OPTAB_FN (COND_ADD, ECF_CONST, cond_add, cond_binary)
> DEF_INTERNAL_OPTAB_FN (COND_LEN_ADD, ECF_CONST, cond_len_add, cond_len_binary)
>
> could become:
>
> DEF_INTERNAL_COND_FN (ADD, ECF_CONST, add, binary)
>
> that expands to the COND_ADD and COND_LEN_ADD definitions. This would
> help to keep the definitions in sync and would make it eaiser to do a
> mapping between COND_* and COND_LEN_*.
>
> Thanks,
> Richard
>
--
Richard Biener <rguenther@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2023-07-31 9:30 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-07-24 11:46 [PATCH] VECT: Support CALL vectorization for COND_LEN_* juzhe.zhong
2023-07-24 14:33 ` Richard Biener
2023-07-24 23:16 ` 钟居哲
2023-07-25 9:41 ` Richard Sandiford
2023-07-25 10:17 ` juzhe.zhong
2023-07-25 10:21 ` Richard Sandiford
2023-07-25 11:31 ` juzhe.zhong
2023-07-25 12:18 ` Richard Sandiford
2023-07-31 9:30 ` Richard Biener
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