[PATCH] s390: Use vpdi and verllg in vec_reve.

[PATCH] s390: Use vpdi and verllg in vec_reve.

[Robin Dapp]

Hi,

swapping the two elements of a V2DImode or V2DFmode vector can be done
with vpdi instead of using the generic way of loading a permutation mask
from the literal pool and vperm.

Analogous to the V2DI/V2DF case reversing the elements of a four-element
vector can be done by first swapping the elements of the first
doubleword as well the ones of the second one and subsequently rotate
the doublewords by 32 bits.

Bootstrapped and regtested, no regressions.

Is it OK?

Regards
 Robin

gcc/ChangeLog:

	PR target/100869
	* config/s390/vector.md (@vpdi4_2<mode>): New pattern.
	(rotl<mode>3_di): New pattern.
	* config/s390/vx-builtins.md: Use vpdi and verll for reversing
	elements.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/zvector/vec-reve-int-long.c: New test.
---
 gcc/config/s390/vector.md                     | 28 +++++++++++++
 gcc/config/s390/vx-builtins.md                | 41 +++++++++++++++++++
 .../s390/zvector/vec-reve-int-long.c          | 31 ++++++++++++++
 3 files changed, 100 insertions(+)
 create mode 100644
gcc/testsuite/gcc.target/s390/zvector/vec-reve-int-long.c

diff --git a/gcc/config/s390/vector.md b/gcc/config/s390/vector.md
index 16b162aae0e5..2207f39b80e4 100644
--- a/gcc/config/s390/vector.md
+++ b/gcc/config/s390/vector.md
@@ -791,6 +791,17 @@ (define_insn "@vpdi4<mode>"
   "vpdi\t%v0,%v1,%v2,4"
   [(set_attr "op_type" "VRR")])

+; Second DW of op1 and first DW of op2 (when interpreted as 2-element
vector).
+(define_insn "@vpdi4_2<mode>"
+  [(set (match_operand:V_HW_4   0 "register_operand" "=v")
+	(vec_select:V_HW_4
+	 (vec_concat:<vec_2x_nelts>
+	  (match_operand:V_HW_4 1 "register_operand"  "v")
+	  (match_operand:V_HW_4 2 "register_operand"  "v"))
+	 (parallel [(const_int 2) (const_int 3) (const_int 4) (const_int 5)])))]
+  "TARGET_VX"
+  "vpdi\t%v0,%v1,%v2,4"
+  [(set_attr "op_type" "VRR")])

 (define_insn "*vmrhb"
   [(set (match_operand:V16QI                     0 "register_operand" "=v")
@@ -1249,6 +1260,23 @@ (define_insn "*<vec_shifts_name><mode>3"
   "<vec_shifts_mnem><bhfgq>\t%v0,%v1,%Y2"
   [(set_attr "op_type" "VRS")])

+; verllg for V4SI/V4SF.  This swaps the first and the second two
+; elements of a vector and is only valid in that context.
+(define_expand "rotl<mode>3_di"
+ [
+ (set (match_dup 2)
+  (subreg:V2DI (match_operand:V_HW_4 1) 0))
+ (set (match_dup 3)
+  (rotate:V2DI
+   (match_dup 2)
+   (const_int 32)))
+ (set (match_operand:V_HW_4 0)
+  (subreg:V_HW_4 (match_dup 3) 0))]
+ "TARGET_VX"
+ {
+  operands[2] = gen_reg_rtx (V2DImode);
+  operands[3] = gen_reg_rtx (V2DImode);
+ })

 ; Shift each element by corresponding vector element

diff --git a/gcc/config/s390/vx-builtins.md b/gcc/config/s390/vx-builtins.md
index c46d16eae484..99c4c037b49a 100644
--- a/gcc/config/s390/vx-builtins.md
+++ b/gcc/config/s390/vx-builtins.md
@@ -2184,6 +2184,47 @@ (define_insn "*eltswap<mode>"
    vster<bhfgq>\t%v1,%v0"
   [(set_attr "op_type" "*,VRX,VRX")])

+; Swapping v2df/v2di can be done via vpdi on z13 and z14.
+(define_split
+  [(set (match_operand:V_HW_2                 0 "register_operand" "")
+	(unspec:V_HW_2 [(match_operand:V_HW_2 1 "register_operand" "")]
+		       UNSPEC_VEC_ELTSWAP))]
+  "TARGET_VX && can_create_pseudo_p ()"
+  [(set (match_operand:V_HW_2     0 "register_operand" "=v")
+	(vec_select:V_HW_2
+	 (vec_concat:<vec_2x_nelts>
+	  (match_operand:V_HW_2 1 "register_operand"  "v")
+	  (match_dup 1))
+	 (parallel [(const_int 1) (const_int 2)])))]
+)
+
+
+; Swapping v4df/v4si can be done via vpdi and rot.
+(define_split
+  [(set (match_operand:V_HW_4                 0 "register_operand" "")
+	(unspec:V_HW_4 [(match_operand:V_HW_4 1 "register_operand" "")]
+		       UNSPEC_VEC_ELTSWAP))]
+  "TARGET_VX && can_create_pseudo_p ()"
+  [(set (match_dup 2)
+	(vec_select:V_HW_4
+	 (vec_concat:<vec_2x_nelts>
+	  (match_dup 1)
+	  (match_dup 1))
+	 (parallel [(const_int 2) (const_int 3) (const_int 4) (const_int 5)])))
+ (set (match_dup 3)
+  (subreg:V2DI (match_dup 2) 0))
+ (set (match_dup 4)
+  (rotate:V2DI
+   (match_dup 3)
+   (const_int 32)))
+ (set (match_operand:V_HW_4 0)
+  (subreg:V_HW_4 (match_dup 4) 0))]
+{
+  operands[2] = gen_reg_rtx (<MODE>mode);
+  operands[3] = gen_reg_rtx (V2DImode);
+  operands[4] = gen_reg_rtx (V2DImode);
+})
+
 ; z15 has instructions for doing element reversal from mem to reg
 ; or the other way around.  For reg to reg or on pre z15 machines
 ; we have to emulate it with vector permute.
diff --git a/gcc/testsuite/gcc.target/s390/zvector/vec-reve-int-long.c
b/gcc/testsuite/gcc.target/s390/zvector/vec-reve-int-long.c
new file mode 100644
index 000000000000..dff3a94066c7
--- /dev/null
+++ b/gcc/testsuite/gcc.target/s390/zvector/vec-reve-int-long.c
@@ -0,0 +1,31 @@
+/* Test that we use vpdi in order to reverse vectors
+   with two elements instead of creating a literal-pool entry
+   and permuting with vperm.  */
+/* { dg-do compile { target { s390*-*-* } } } */
+/* { dg-options "-O2 -march=z14 -mzarch -mzvector -fno-unroll-loops" } */
+
+/* { dg-final { scan-assembler-times "vpdi\t" 4 } } */
+/* { dg-final { scan-assembler-times "verllg\t" 2 } } */
+/* { dg-final { scan-assembler-times "vperm" 0 } } */
+
+#include <vecintrin.h>
+
+vector double reved (vector double a)
+{
+   return vec_reve (a);
+}
+
+vector long long revel (vector long long a)
+{
+   return vec_reve (a);
+}
+
+vector float revef (vector float a)
+{
+   return vec_reve (a);
+}
+
+vector int revei (vector int a)
+{
+   return vec_reve (a);
+}
-- 
2.31.1

Re: [PATCH] s390: Use vpdi and verllg in vec_reve.

[Andreas Krebbel]

On 8/12/22 12:13, Robin Dapp wrote:
> Hi,
> 
> swapping the two elements of a V2DImode or V2DFmode vector can be done
> with vpdi instead of using the generic way of loading a permutation mask
> from the literal pool and vperm.
> 
> Analogous to the V2DI/V2DF case reversing the elements of a four-element
> vector can be done by first swapping the elements of the first
> doubleword as well the ones of the second one and subsequently rotate
> the doublewords by 32 bits.
> 
> Bootstrapped and regtested, no regressions.
> 
> Is it OK?
> 
> Regards
>  Robin
> 
> gcc/ChangeLog:
> 
> 	PR target/100869
> 	* config/s390/vector.md (@vpdi4_2<mode>): New pattern.
> 	(rotl<mode>3_di): New pattern.
> 	* config/s390/vx-builtins.md: Use vpdi and verll for reversing
> 	elements.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* gcc.target/s390/zvector/vec-reve-int-long.c: New test.

Ok. Thanks!

Andreas