Re: [PATCH V2] Support folding min(poly,poly) to const
Sorry, just realised that the poly_int_tree_p tests are redundant. The
caller has already checked that.
Indeed, I will removed poly_int_tree_p tests like the following code.
Thanks for timely remind.
/* Returns true if we know who is smaller or equal, ARG1 or ARG2, and
set the
min value to RES. */
bool
can_min_p (const_tree arg1, const_tree arg2, poly_wide_int &res)
{
if (known_le (wi::to_poly_widest (arg1), wi::to_poly_widest (arg2)))
{
res = wi::to_poly_wide (arg1);
return true;
}
else if (known_le (wi::to_poly_widest (arg2), wi::to_poly_widest (arg1)))
{
res = wi::to_poly_wide (arg2);
return true;
}
return false;
}
--
Best,
Lehua
Re: [PATCH V2] Support folding min(poly,poly) to const
Richard Sandiford writes:
> Lehua Ding writes:
>> Hi,
>>
>> This patch adds support that tries to fold `MIN (poly, poly)` to
>> a constant. Consider the following C Code:
>>
>> ```
>> void foo2 (int* restrict a, int* restrict b, int n)
>> {
>> for (int i = 0; i < 3; i += 1)
>> a[i] += b[i];
>> }
>> ```
>>
>> Before this patch:
>>
>> ```
>> void foo2 (int * restrict a, int * restrict b, int n)
>> {
>> vector([4,4]) int vect__7.27;
>> vector([4,4]) int vect__6.26;
>> vector([4,4]) int vect__4.23;
>> unsigned long _32;
>>
>>[local count: 268435456]:
>> _32 = MIN_EXPR <3, POLY_INT_CST [4, 4]>;
>> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, _32, 0);
>> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, _32, 0);
>> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
>> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, _32, 0, vect__7.27_9); [tail
>> call]
>> return;
>>
>> }
>> ```
>>
>> After this patch:
>>
>> ```
>> void foo2 (int * restrict a, int * restrict b, int n)
>> {
>> vector([4,4]) int vect__7.27;
>> vector([4,4]) int vect__6.26;
>> vector([4,4]) int vect__4.23;
>>
>>[local count: 268435456]:
>> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, 3, 0);
>> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, 3, 0);
>> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
>> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, 3, 0, vect__7.27_9); [tail
>> call]
>> return;
>>
>> }
>> ```
>>
>> For RISC-V RVV, csrr and branch instructions can be reduced:
>>
>> Before this patch:
>>
>> ```
>> foo2:
>> csrra4,vlenb
>> srlia4,a4,2
>> li a5,3
>> bleua5,a4,.L5
>> mv a5,a4
>> .L5:
>> vsetvli zero,a5,e32,m1,ta,ma
>> ...
>> ```
>>
>> After this patch.
>>
>> ```
>> foo2:
>> vsetivlizero,3,e32,m1,ta,ma
>> ...
>> ```
>>
>> Best,
>> Lehua
>>
>> gcc/ChangeLog:
>>
>> * fold-const.cc (can_min_p): New function.
>> (poly_int_binop): Try fold MIN_EXPR.
>
> OK, thanks.
Sorry, just realised that the poly_int_tree_p tests are redundant.
The caller has already checked that.
Richard
> Richard
>
>> gcc/testsuite/ChangeLog:
>>
>> * gcc.target/riscv/rvv/autovec/vls/div-1.c: Adjust.
>> * gcc.target/riscv/rvv/autovec/vls/shift-3.c: Adjust.
>> * gcc.target/riscv/rvv/autovec/fold-min-poly.c: New test.
>>
>> ---
>> gcc/fold-const.cc | 27 +++
>> .../riscv/rvv/autovec/fold-min-poly.c | 24 +
>> .../gcc.target/riscv/rvv/autovec/vls/div-1.c | 2 +-
>> .../riscv/rvv/autovec/vls/shift-3.c | 2 +-
>> 4 files changed, 53 insertions(+), 2 deletions(-)
>> create mode 100644
>> gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>>
>> diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
>> index 1da498a3152..ba4b6f3f3a3 100644
>> --- a/gcc/fold-const.cc
>> +++ b/gcc/fold-const.cc
>> @@ -1213,6 +1213,28 @@ wide_int_binop (wide_int &res,
>>return true;
>> }
>>
>> +/* Returns true if we know who is smaller or equal, ARG1 or ARG2, and set
>> the
>> + min value to RES. */
>> +bool
>> +can_min_p (const_tree arg1, const_tree arg2, poly_wide_int &res)
>> +{
>> + if (!poly_int_tree_p (arg1) || !poly_int_tree_p (arg2))
>> +return false;
>> +
>> + if (known_le (wi::to_poly_widest (arg1), wi::to_poly_widest (arg2)))
>> +{
>> + res = wi::to_poly_wide (arg1);
>> + return true;
>> +}
>> + else if (known_le (wi::to_poly_widest (arg2), wi::to_poly_widest (arg1)))
>> +{
>> + res = wi::to_poly_wide (arg2);
>> + return true;
>> +}
>> +
>> + return false;
>> +}
>> +
>> /* Combine two poly int's ARG1 and ARG2 under operation CODE to
>> produce a new constant in RES. Return FALSE if we don't know how
>> to evaluate CODE at compile-time. */
>> @@ -1261,6 +1283,11 @@ poly_int_binop (poly_wide_int &res, enum tree_code
>> code,
>> return false;
>>break;
>>
>> +case MIN_EXPR:
>> + if (!can_min_p (arg1, arg2, res))
>> +return false;
>> + break;
>> +
>> default:
>>return false;
>> }
>> diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>> b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>> new file mode 100644
>> index 000..de4c472c76e
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>> @@ -0,0 +1,24 @@
>> +/* { dg-do compile } */
>> +/* { dg-options " -march=rv64gcv_zvl128b -mabi=lp64d -O3 --param
>> riscv-autovec-preference=scalable --param riscv-autovec-lmul=m1
>> -fno-vect-cost-model" } */
>> +
>> +void foo1 (int* restrict a, int* restrict b, int n)
>> +{
>> +for (int i = 0; i < 4; i += 1)
>> + a[i] += b[i];
>> +}
>> +
>> +void foo2 (int* restrict a, int* restrict b, int n)
>> +{
>> +for (int i = 0; i < 3; i += 1)
>> + a[i] += b[i];
>> +}
>> +
>> +void foo3 (int* restrict a, int* re
Re: Re: [PATCH V2] Support folding min(poly,poly) to const
Thanks Richard and Lehua.
LGTM from RISC-V side.
juzhe.zh...@rivai.ai
From: Richard Sandiford
Date: 2023-09-08 16:12
To: Lehua Ding
CC: gcc-patches; richard.guenther; juzhe.zhong; jeffreyalaw
Subject: Re: [PATCH V2] Support folding min(poly,poly) to const
Lehua Ding writes:
> Hi,
>
> This patch adds support that tries to fold `MIN (poly, poly)` to
> a constant. Consider the following C Code:
>
> ```
> void foo2 (int* restrict a, int* restrict b, int n)
> {
> for (int i = 0; i < 3; i += 1)
> a[i] += b[i];
> }
> ```
>
> Before this patch:
>
> ```
> void foo2 (int * restrict a, int * restrict b, int n)
> {
> vector([4,4]) int vect__7.27;
> vector([4,4]) int vect__6.26;
> vector([4,4]) int vect__4.23;
> unsigned long _32;
>
>[local count: 268435456]:
> _32 = MIN_EXPR <3, POLY_INT_CST [4, 4]>;
> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, _32, 0);
> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, _32, 0);
> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, _32, 0, vect__7.27_9); [tail
> call]
> return;
>
> }
> ```
>
> After this patch:
>
> ```
> void foo2 (int * restrict a, int * restrict b, int n)
> {
> vector([4,4]) int vect__7.27;
> vector([4,4]) int vect__6.26;
> vector([4,4]) int vect__4.23;
>
>[local count: 268435456]:
> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, 3, 0);
> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, 3, 0);
> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, 3, 0, vect__7.27_9); [tail call]
> return;
>
> }
> ```
>
> For RISC-V RVV, csrr and branch instructions can be reduced:
>
> Before this patch:
>
> ```
> foo2:
> csrra4,vlenb
> srlia4,a4,2
> li a5,3
> bleua5,a4,.L5
> mv a5,a4
> .L5:
> vsetvli zero,a5,e32,m1,ta,ma
> ...
> ```
>
> After this patch.
>
> ```
> foo2:
> vsetivli zero,3,e32,m1,ta,ma
> ...
> ```
>
> Best,
> Lehua
>
> gcc/ChangeLog:
>
> * fold-const.cc (can_min_p): New function.
> (poly_int_binop): Try fold MIN_EXPR.
OK, thanks.
Richard
> gcc/testsuite/ChangeLog:
>
> * gcc.target/riscv/rvv/autovec/vls/div-1.c: Adjust.
> * gcc.target/riscv/rvv/autovec/vls/shift-3.c: Adjust.
> * gcc.target/riscv/rvv/autovec/fold-min-poly.c: New test.
>
> ---
> gcc/fold-const.cc | 27 +++
> .../riscv/rvv/autovec/fold-min-poly.c | 24 +
> .../gcc.target/riscv/rvv/autovec/vls/div-1.c | 2 +-
> .../riscv/rvv/autovec/vls/shift-3.c | 2 +-
> 4 files changed, 53 insertions(+), 2 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>
> diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
> index 1da498a3152..ba4b6f3f3a3 100644
> --- a/gcc/fold-const.cc
> +++ b/gcc/fold-const.cc
> @@ -1213,6 +1213,28 @@ wide_int_binop (wide_int &res,
>return true;
> }
>
> +/* Returns true if we know who is smaller or equal, ARG1 or ARG2, and set the
> + min value to RES. */
> +bool
> +can_min_p (const_tree arg1, const_tree arg2, poly_wide_int &res)
> +{
> + if (!poly_int_tree_p (arg1) || !poly_int_tree_p (arg2))
> +return false;
> +
> + if (known_le (wi::to_poly_widest (arg1), wi::to_poly_widest (arg2)))
> +{
> + res = wi::to_poly_wide (arg1);
> + return true;
> +}
> + else if (known_le (wi::to_poly_widest (arg2), wi::to_poly_widest (arg1)))
> +{
> + res = wi::to_poly_wide (arg2);
> + return true;
> +}
> +
> + return false;
> +}
> +
> /* Combine two poly int's ARG1 and ARG2 under operation CODE to
> produce a new constant in RES. Return FALSE if we don't know how
> to evaluate CODE at compile-time. */
> @@ -1261,6 +1283,11 @@ poly_int_binop (poly_wide_int &res, enum tree_code
> code,
> return false;
>break;
>
> +case MIN_EXPR:
> + if (!can_min_p (arg1, arg2, res))
> + return false;
> + break;
> +
> default:
>return false;
> }
> diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> new file mode 100644
> index 000..de4c472c76e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> @@ -0,0 +1,24 @@
> +/* { dg-do compile } */
> +/* { dg-options " -march=rv64gcv_zvl128b -mabi=lp64d -O3 --param
> ris
Re: [PATCH V2] Support folding min(poly,poly) to const
Lehua Ding writes:
> Hi,
>
> This patch adds support that tries to fold `MIN (poly, poly)` to
> a constant. Consider the following C Code:
>
> ```
> void foo2 (int* restrict a, int* restrict b, int n)
> {
> for (int i = 0; i < 3; i += 1)
> a[i] += b[i];
> }
> ```
>
> Before this patch:
>
> ```
> void foo2 (int * restrict a, int * restrict b, int n)
> {
> vector([4,4]) int vect__7.27;
> vector([4,4]) int vect__6.26;
> vector([4,4]) int vect__4.23;
> unsigned long _32;
>
>[local count: 268435456]:
> _32 = MIN_EXPR <3, POLY_INT_CST [4, 4]>;
> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, _32, 0);
> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, _32, 0);
> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, _32, 0, vect__7.27_9); [tail
> call]
> return;
>
> }
> ```
>
> After this patch:
>
> ```
> void foo2 (int * restrict a, int * restrict b, int n)
> {
> vector([4,4]) int vect__7.27;
> vector([4,4]) int vect__6.26;
> vector([4,4]) int vect__4.23;
>
>[local count: 268435456]:
> vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, 3, 0);
> vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, 3, 0);
> vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
> .MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, 3, 0, vect__7.27_9); [tail call]
> return;
>
> }
> ```
>
> For RISC-V RVV, csrr and branch instructions can be reduced:
>
> Before this patch:
>
> ```
> foo2:
> csrra4,vlenb
> srlia4,a4,2
> li a5,3
> bleua5,a4,.L5
> mv a5,a4
> .L5:
> vsetvli zero,a5,e32,m1,ta,ma
> ...
> ```
>
> After this patch.
>
> ```
> foo2:
> vsetivlizero,3,e32,m1,ta,ma
> ...
> ```
>
> Best,
> Lehua
>
> gcc/ChangeLog:
>
> * fold-const.cc (can_min_p): New function.
> (poly_int_binop): Try fold MIN_EXPR.
OK, thanks.
Richard
> gcc/testsuite/ChangeLog:
>
> * gcc.target/riscv/rvv/autovec/vls/div-1.c: Adjust.
> * gcc.target/riscv/rvv/autovec/vls/shift-3.c: Adjust.
> * gcc.target/riscv/rvv/autovec/fold-min-poly.c: New test.
>
> ---
> gcc/fold-const.cc | 27 +++
> .../riscv/rvv/autovec/fold-min-poly.c | 24 +
> .../gcc.target/riscv/rvv/autovec/vls/div-1.c | 2 +-
> .../riscv/rvv/autovec/vls/shift-3.c | 2 +-
> 4 files changed, 53 insertions(+), 2 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
>
> diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
> index 1da498a3152..ba4b6f3f3a3 100644
> --- a/gcc/fold-const.cc
> +++ b/gcc/fold-const.cc
> @@ -1213,6 +1213,28 @@ wide_int_binop (wide_int &res,
>return true;
> }
>
> +/* Returns true if we know who is smaller or equal, ARG1 or ARG2, and set the
> + min value to RES. */
> +bool
> +can_min_p (const_tree arg1, const_tree arg2, poly_wide_int &res)
> +{
> + if (!poly_int_tree_p (arg1) || !poly_int_tree_p (arg2))
> +return false;
> +
> + if (known_le (wi::to_poly_widest (arg1), wi::to_poly_widest (arg2)))
> +{
> + res = wi::to_poly_wide (arg1);
> + return true;
> +}
> + else if (known_le (wi::to_poly_widest (arg2), wi::to_poly_widest (arg1)))
> +{
> + res = wi::to_poly_wide (arg2);
> + return true;
> +}
> +
> + return false;
> +}
> +
> /* Combine two poly int's ARG1 and ARG2 under operation CODE to
> produce a new constant in RES. Return FALSE if we don't know how
> to evaluate CODE at compile-time. */
> @@ -1261,6 +1283,11 @@ poly_int_binop (poly_wide_int &res, enum tree_code
> code,
> return false;
>break;
>
> +case MIN_EXPR:
> + if (!can_min_p (arg1, arg2, res))
> + return false;
> + break;
> +
> default:
>return false;
> }
> diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> new file mode 100644
> index 000..de4c472c76e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
> @@ -0,0 +1,24 @@
> +/* { dg-do compile } */
> +/* { dg-options " -march=rv64gcv_zvl128b -mabi=lp64d -O3 --param
> riscv-autovec-preference=scalable --param riscv-autovec-lmul=m1
> -fno-vect-cost-model" } */
> +
> +void foo1 (int* restrict a, int* restrict b, int n)
> +{
> +for (int i = 0; i < 4; i += 1)
> + a[i] += b[i];
> +}
> +
> +void foo2 (int* restrict a, int* restrict b, int n)
> +{
> +for (int i = 0; i < 3; i += 1)
> + a[i] += b[i];
> +}
> +
> +void foo3 (int* restrict a, int* restrict b, int n)
> +{
> +for (int i = 0; i < 5; i += 1)
> + a[i] += b[i];
> +}
> +
> +/* { dg-final { scan-assembler-not {\tcsrr\t} } } */
> +/* { dg-final { scan-assembler {\tvsetivli\tzero,4,e32,m1,t[au],m[au]} } } */
> +/* { dg-final { scan-assembler {\tvsetivli\tzero,3,e32,m1,t[au],m[au]} } } */
> diff --git
[PATCH V2] Support folding min(poly,poly) to const
Hi,
This patch adds support that tries to fold `MIN (poly, poly)` to
a constant. Consider the following C Code:
```
void foo2 (int* restrict a, int* restrict b, int n)
{
for (int i = 0; i < 3; i += 1)
a[i] += b[i];
}
```
Before this patch:
```
void foo2 (int * restrict a, int * restrict b, int n)
{
vector([4,4]) int vect__7.27;
vector([4,4]) int vect__6.26;
vector([4,4]) int vect__4.23;
unsigned long _32;
[local count: 268435456]:
_32 = MIN_EXPR <3, POLY_INT_CST [4, 4]>;
vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, _32, 0);
vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, _32, 0);
vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
.MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, _32, 0, vect__7.27_9); [tail call]
return;
}
```
After this patch:
```
void foo2 (int * restrict a, int * restrict b, int n)
{
vector([4,4]) int vect__7.27;
vector([4,4]) int vect__6.26;
vector([4,4]) int vect__4.23;
[local count: 268435456]:
vect__4.23_20 = .MASK_LEN_LOAD (a_11(D), 32B, { -1, ... }, 3, 0);
vect__6.26_15 = .MASK_LEN_LOAD (b_12(D), 32B, { -1, ... }, 3, 0);
vect__7.27_9 = vect__6.26_15 + vect__4.23_20;
.MASK_LEN_STORE (a_11(D), 32B, { -1, ... }, 3, 0, vect__7.27_9); [tail call]
return;
}
```
For RISC-V RVV, csrr and branch instructions can be reduced:
Before this patch:
```
foo2:
csrra4,vlenb
srlia4,a4,2
li a5,3
bleua5,a4,.L5
mv a5,a4
.L5:
vsetvli zero,a5,e32,m1,ta,ma
...
```
After this patch.
```
foo2:
vsetivlizero,3,e32,m1,ta,ma
...
```
Best,
Lehua
gcc/ChangeLog:
* fold-const.cc (can_min_p): New function.
(poly_int_binop): Try fold MIN_EXPR.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/autovec/vls/div-1.c: Adjust.
* gcc.target/riscv/rvv/autovec/vls/shift-3.c: Adjust.
* gcc.target/riscv/rvv/autovec/fold-min-poly.c: New test.
---
gcc/fold-const.cc | 27 +++
.../riscv/rvv/autovec/fold-min-poly.c | 24 +
.../gcc.target/riscv/rvv/autovec/vls/div-1.c | 2 +-
.../riscv/rvv/autovec/vls/shift-3.c | 2 +-
4 files changed, 53 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 1da498a3152..ba4b6f3f3a3 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -1213,6 +1213,28 @@ wide_int_binop (wide_int &res,
return true;
}
+/* Returns true if we know who is smaller or equal, ARG1 or ARG2, and set the
+ min value to RES. */
+bool
+can_min_p (const_tree arg1, const_tree arg2, poly_wide_int &res)
+{
+ if (!poly_int_tree_p (arg1) || !poly_int_tree_p (arg2))
+return false;
+
+ if (known_le (wi::to_poly_widest (arg1), wi::to_poly_widest (arg2)))
+{
+ res = wi::to_poly_wide (arg1);
+ return true;
+}
+ else if (known_le (wi::to_poly_widest (arg2), wi::to_poly_widest (arg1)))
+{
+ res = wi::to_poly_wide (arg2);
+ return true;
+}
+
+ return false;
+}
+
/* Combine two poly int's ARG1 and ARG2 under operation CODE to
produce a new constant in RES. Return FALSE if we don't know how
to evaluate CODE at compile-time. */
@@ -1261,6 +1283,11 @@ poly_int_binop (poly_wide_int &res, enum tree_code code,
return false;
break;
+case MIN_EXPR:
+ if (!can_min_p (arg1, arg2, res))
+ return false;
+ break;
+
default:
return false;
}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
new file mode 100644
index 000..de4c472c76e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/fold-min-poly.c
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-options " -march=rv64gcv_zvl128b -mabi=lp64d -O3 --param
riscv-autovec-preference=scalable --param riscv-autovec-lmul=m1
-fno-vect-cost-model" } */
+
+void foo1 (int* restrict a, int* restrict b, int n)
+{
+for (int i = 0; i < 4; i += 1)
+ a[i] += b[i];
+}
+
+void foo2 (int* restrict a, int* restrict b, int n)
+{
+for (int i = 0; i < 3; i += 1)
+ a[i] += b[i];
+}
+
+void foo3 (int* restrict a, int* restrict b, int n)
+{
+for (int i = 0; i < 5; i += 1)
+ a[i] += b[i];
+}
+
+/* { dg-final { scan-assembler-not {\tcsrr\t} } } */
+/* { dg-final { scan-assembler {\tvsetivli\tzero,4,e32,m1,t[au],m[au]} } } */
+/* { dg-final { scan-assembler {\tvsetivli\tzero,3,e32,m1,t[au],m[au]} } } */
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/div-1.c
b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/div-1.c
index f3388a86e38..40224c69458 100644
--- a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/div-1.c
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/div-1.c
@@ -55,4 +55,4 @@ DEF_OP_VV (div, 512, int64_t, /)
/* { dg-final { scan-assembler-times
