arm: Auto-vectorization for MVE: vmul

This patch enables MVE vmul instructions for auto-vectorization.
It includes MVE in expander mul<mode>3 to enable vectorization for MVE.
Related MVE vmul insns are modified to support the expander by using
expression 'mult' instead of unspec.
The mul<mode>3 for vectorization in vec-common.md uses mode iterator
VDQWH instead of VALLW to cover all supported modes.
The macros ARM_HAVE_NEON_<MODE>_ARITH are used to select supported
modes for different targets.
The redundant mul<mode>3 in neon.md is removed.

gcc/ChangeLog:

2020-10-22  Dennis Zhang  <dennis.zhang@arm.com>

	* config/arm/mve.md (mve_vmulq<mode>): New entry for vmul instruction
	using expression 'mult'.
	(mve_vmulq_f<mode>): Use mult instead of VMULQ_F.
	* config/arm/neon.md (mul<mode>3): Removed.
	* config/arm/vec-common.md (mul<mode>3): Use the new mode macros
	ARM_HAVE_<MODE>_ARITH. Use mode iterator VDQWH instead of VALLW.

gcc/testsuite/ChangeLog:

	* gcc.target/arm/simd/mve-vmul_1.c: New test.

6 files changed, 95 insertions, 22 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a44bc09..d6a326c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2020-10-22  Dennis Zhang  <dennis.zhang@arm.com>
+
+	* config/arm/mve.md (mve_vmulq<mode>): New entry for vmul instruction
+	using expression 'mult'.
+	(mve_vmulq_f<mode>): Use mult instead of VMULQ_F.
+	* config/arm/neon.md (mul<mode>3): Removed.
+	* config/arm/vec-common.md (mul<mode>3): Use the new mode macros
+	ARM_HAVE_<MODE>_ARITH. Use mode iterator VDQWH instead of VALLW.
+
 2020-10-20  Andrew MacLeod  <amacleod@redhat.com>
 
 	PR tree-optimization/97505
diff --git a/gcc/config/arm/mve.md b/gcc/config/arm/mve.md
index 5dad388..764e201 100644
--- a/gcc/config/arm/mve.md
+++ b/gcc/config/arm/mve.md
@@ -1551,6 +1551,17 @@
   [(set_attr "type" "mve_move")
 ])
 
+(define_insn "mve_vmulq<mode>"
+  [
+   (set (match_operand:MVE_2 0 "s_register_operand" "=w")
+	(mult:MVE_2 (match_operand:MVE_2 1 "s_register_operand" "w")
+		    (match_operand:MVE_2 2 "s_register_operand" "w")))
+  ]
+  "TARGET_HAVE_MVE"
+  "vmul.i%#<V_sz_elem>\t%q0, %q1, %q2"
+  [(set_attr "type" "mve_move")
+])
+
 ;;
 ;; [vornq_u, vornq_s])
 ;;
@@ -2562,9 +2573,8 @@
 (define_insn "mve_vmulq_f<mode>"
   [
    (set (match_operand:MVE_0 0 "s_register_operand" "=w")
-	(unspec:MVE_0 [(match_operand:MVE_0 1 "s_register_operand" "w")
-		       (match_operand:MVE_0 2 "s_register_operand" "w")]
-	 VMULQ_F))
+	(mult:MVE_0 (match_operand:MVE_0 1 "s_register_operand" "w")
+		    (match_operand:MVE_0 2 "s_register_operand" "w")))
   ]
   "TARGET_HAVE_MVE && TARGET_HAVE_MVE_FLOAT"
   "vmul.f%#<V_sz_elem>	%q0, %q1, %q2"
diff --git a/gcc/config/arm/neon.md b/gcc/config/arm/neon.md
index 85e424e..e459b9a 100644
--- a/gcc/config/arm/neon.md
+++ b/gcc/config/arm/neon.md
@@ -1732,17 +1732,6 @@
                     (const_string "neon_mul_<V_elem_ch><q>")))]
 )
 
-(define_insn "mul<mode>3"
- [(set
-   (match_operand:VH 0 "s_register_operand" "=w")
-   (mult:VH
-    (match_operand:VH 1 "s_register_operand" "w")
-    (match_operand:VH 2 "s_register_operand" "w")))]
-  "ARM_HAVE_NEON_<MODE>_ARITH"
-  "vmul.f16\t%<V_reg>0, %<V_reg>1, %<V_reg>2"
- [(set_attr "type" "neon_mul_<VH_elem_ch><q>")]
-)
-
 (define_insn "neon_vmulf<mode>"
  [(set
    (match_operand:VH 0 "s_register_operand" "=w")
diff --git a/gcc/config/arm/vec-common.md b/gcc/config/arm/vec-common.md
index c3c86c4..45db60e 100644
--- a/gcc/config/arm/vec-common.md
+++ b/gcc/config/arm/vec-common.md
@@ -101,14 +101,11 @@
 })
 
 (define_expand "mul<mode>3"
-  [(set (match_operand:VALLW 0 "s_register_operand")
-        (mult:VALLW (match_operand:VALLW 1 "s_register_operand")
-		    (match_operand:VALLW 2 "s_register_operand")))]
-  "(TARGET_NEON && ((<MODE>mode != V2SFmode && <MODE>mode != V4SFmode)
-		    || flag_unsafe_math_optimizations))
-   || (<MODE>mode == V4HImode && TARGET_REALLY_IWMMXT)"
-{
-})
+  [(set (match_operand:VDQWH 0 "s_register_operand")
+	(mult:VDQWH (match_operand:VDQWH 1 "s_register_operand")
+		    (match_operand:VDQWH 2 "s_register_operand")))]
+  "ARM_HAVE_<MODE>_ARITH"
+)
 
 (define_expand "smin<mode>3"
   [(set (match_operand:VALLW 0 "s_register_operand")
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 649f2bd..eb55a64 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2020-10-22  Dennis Zhang  <dennis.zhang@arm.com>
+
+	* gcc.target/arm/simd/mve-vmul_1.c: New test.
+
 2020-10-20  Jeff Law  <law@redhat.com>
 
 	* gcc.dg/Wbuiltin-declaration-mismatch-9.c: Improve pruning of
diff --git a/gcc/testsuite/gcc.target/arm/simd/mve-vmul_1.c b/gcc/testsuite/gcc.target/arm/simd/mve-vmul_1.c
new file mode 100644
index 0000000..514f292
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/simd/mve-vmul_1.c
@@ -0,0 +1,64 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_v8_1m_mve_fp_ok } */
+/* { dg-add-options arm_v8_1m_mve_fp } */
+/* { dg-additional-options "-O3" } */
+
+#include <stdint.h>
+
+void test_vmul_i32 (int32_t * dest, int32_t * a, int32_t * b) {
+  int i;
+  for (i=0; i<4; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+void test_vmul_i32_u (uint32_t * dest, uint32_t * a, uint32_t * b) {
+  int i;
+  for (i=0; i<4; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+/* { dg-final { scan-assembler-times {vmul\.i32\tq[0-9]+, q[0-9]+, q[0-9]+} 2 } } */
+
+void test_vmul_i16 (int16_t * dest, int16_t * a, int16_t * b) {
+  int i;
+  for (i=0; i<8; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+void test_vmul_i16_u (uint16_t * dest, uint16_t * a, uint16_t * b) {
+  int i;
+  for (i=0; i<8; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+/* { dg-final { scan-assembler-times {vmul\.i16\tq[0-9]+, q[0-9]+, q[0-9]+} 2 } } */
+
+void test_vmul_i8 (int8_t * dest, int8_t * a, int8_t * b) {
+  int i;
+  for (i=0; i<16; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+void test_vmul_i8_u (uint8_t * dest, uint8_t * a, uint8_t * b) {
+  int i;
+  for (i=0; i<16; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+/* { dg-final { scan-assembler-times {vmul\.i8\tq[0-9]+, q[0-9]+, q[0-9]+} 2 } } */
+
+void test_vmul_f32 (float * dest, float * a, float * b) {
+  int i;
+  for (i=0; i<4; i++) {
+    dest[i] = a[i] * b[i];
+  }
+}
+
+/* { dg-final { scan-assembler-times {vmul\.f32\tq[0-9]+, q[0-9]+, q[0-9]+} 1 } } */
+