gcc, Arm: Fix MVE move from GPR -> GPR

This patch fixes the pattern mve_mov for the case where both MVE vectors are in
R registers and the move does not get optimized away.  I use the same approach
as we do for NEON, where we use four register moves.

gcc/ChangeLog:
2020-03-20  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* config/arm/mve.md (mve_mov<mode>): Fix R->R case.

gcc/testsuite/ChangeLog:
2020-03-20  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* gcc.target/arm/mve/intrinsics/mve_move_gpr_to_gpr.c: New test.

gcc/ChangeLog

+2020-03-20  Andre Vieira  <andre.simoesdiasvieira@arm.com>
+
+	* config/arm/mve.md (mve_mov<mode>): Fix R->R case.
+
 2020-03-20  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/94224

gcc/config/arm/mve.md

@@ -663,7 +663,7 @@
       else
 	return "vldrb.8 %q0, %E1";
     case 5:
-      return output_move_neon (operands);
+      return output_move_quad (operands);
     case 7:
       return "vstrb.8 %q1, %E0";
     default:
@@ -671,7 +671,7 @@
       return "";
     }
 }
-  [(set_attr "type" "mve_move,mve_move,mve_move,mve_move,mve_load,mve_move,mve_move,mve_store")
+  [(set_attr "type" "mve_move,mve_move,mve_move,mve_move,mve_load,multiple,mve_move,mve_store")
    (set_attr "length" "4,8,8,4,8,8,4,4")
    (set_attr "thumb2_pool_range" "*,*,*,*,1018,*,*,*")
    (set_attr "neg_pool_range" "*,*,*,*,996,*,*,*")])

gcc/testsuite/ChangeLog

+2020-03-20  Andre Vieira  <andre.simoesdiasvieira@arm.com>
+
+	* gcc.target/arm/mve/intrinsics/mve_move_gpr_to_gpr.c: New test.
+
 2020-03-20  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/94224

gcc/testsuite/gcc.target/arm/mve/intrinsics/mve_move_gpr_to_gpr.c

+/* { dg-do compile  } */
+/* { dg-require-effective-target arm_v8_1m_mve_fp_ok } */
+/* { dg-add-options arm_v8_1m_mve_fp } */
+/* { dg-additional-options "-O2 -mfloat-abi=softfp" } */
+
+#include "arm_mve.h"
+
+extern int bar (float16x8_t, float16_t);
+
+extern void foobar (float16_t);
+
+int
+foo (float16x8_t a, float16_t b)
+{
+  foobar (b);
+  return bar (a, b);
+}
+