s390: Try to emit vlbr/vstbr instead of vperm et al.

gcc/ChangeLog:

	* config/s390/s390.cc (expand_perm_as_a_vlbr_vstbr_candidate):
	New function which handles bswap patterns for vec_perm_const.
	(vectorize_vec_perm_const_1): Call new function.
	* config/s390/vector.md (*bswap<mode>): Fix operands in output
	template.
	(*vstbr<mode>): New insn.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/s390.exp: Add subdirectory vxe2.
	* gcc.target/s390/vxe2/vlbr-1.c: New test.
	* gcc.target/s390/vxe2/vstbr-1.c: New test.
	* gcc.target/s390/vxe2/vstbr-2.c: New test.

2 files changed, 67 insertions, 4 deletions

diff --git a/gcc/config/s390/s390.cc b/gcc/config/s390/s390.cc
index 89474fd..6ae81d6 100644
--- a/gcc/config/s390/s390.cc
+++ b/gcc/config/s390/s390.cc
@@ -17704,6 +17704,58 @@ expand_perm_with_vstbrq (const struct expand_vec_perm_d &d)
   return false;
 }
 
+/* Try to emit vlbr/vstbr.  Note, this is only a candidate insn since
+   TARGET_VECTORIZE_VEC_PERM_CONST operates on vector registers only.  Thus,
+   either fwprop, combine et al. "fixes" one of the input/output operands into
+   a memory operand or a splitter has to reverse this into a general vperm
+   operation.  */
+
+static bool
+expand_perm_as_a_vlbr_vstbr_candidate (const struct expand_vec_perm_d &d)
+{
+  static const char perm[4][MAX_VECT_LEN]
+    = { { 1,  0,  3,  2,  5,  4,  7, 6, 9,  8,  11, 10, 13, 12, 15, 14 },
+	{ 3,  2,  1,  0,  7,  6,  5, 4, 11, 10, 9,  8,  15, 14, 13, 12 },
+	{ 7,  6,  5,  4,  3,  2,  1, 0, 15, 14, 13, 12, 11, 10, 9,  8  },
+	{ 15, 14, 13, 12, 11, 10, 9, 8, 7,  6,  5,  4,  3,  2,  1,  0  } };
+
+  if (!TARGET_VXE2 || d.vmode != V16QImode || d.op0 != d.op1)
+    return false;
+
+  if (memcmp (d.perm, perm[0], MAX_VECT_LEN) == 0)
+    {
+      rtx target = gen_rtx_SUBREG (V8HImode, d.target, 0);
+      rtx op0 = gen_rtx_SUBREG (V8HImode, d.op0, 0);
+      emit_insn (gen_bswapv8hi (target, op0));
+      return true;
+    }
+
+  if (memcmp (d.perm, perm[1], MAX_VECT_LEN) == 0)
+    {
+      rtx target = gen_rtx_SUBREG (V4SImode, d.target, 0);
+      rtx op0 = gen_rtx_SUBREG (V4SImode, d.op0, 0);
+      emit_insn (gen_bswapv4si (target, op0));
+      return true;
+    }
+
+  if (memcmp (d.perm, perm[2], MAX_VECT_LEN) == 0)
+    {
+      rtx target = gen_rtx_SUBREG (V2DImode, d.target, 0);
+      rtx op0 = gen_rtx_SUBREG (V2DImode, d.op0, 0);
+      emit_insn (gen_bswapv2di (target, op0));
+      return true;
+    }
+
+  if (memcmp (d.perm, perm[3], MAX_VECT_LEN) == 0)
+    {
+      rtx target = gen_rtx_SUBREG (V1TImode, d.target, 0);
+      rtx op0 = gen_rtx_SUBREG (V1TImode, d.op0, 0);
+      emit_insn (gen_bswapv1ti (target, op0));
+      return true;
+    }
+
+  return false;
+}
 
 /* Try to find the best sequence for the vector permute operation
    described by D.  Return true if the operation could be
@@ -17726,6 +17778,9 @@ vectorize_vec_perm_const_1 (const struct expand_vec_perm_d &d)
   if (expand_perm_with_rot (d))
     return true;
 
+  if (expand_perm_as_a_vlbr_vstbr_candidate (d))
+    return true;
+
   return false;
 }
 
diff --git a/gcc/config/s390/vector.md b/gcc/config/s390/vector.md
index 21bec72..f0e9ed3 100644
--- a/gcc/config/s390/vector.md
+++ b/gcc/config/s390/vector.md
@@ -47,6 +47,7 @@
 (define_mode_iterator VI_HW     [V16QI V8HI V4SI V2DI])
 (define_mode_iterator VI_HW_QHS [V16QI V8HI V4SI])
 (define_mode_iterator VI_HW_HSD [V8HI  V4SI V2DI])
+(define_mode_iterator VI_HW_HSDT [V8HI V4SI V2DI V1TI TI])
 (define_mode_iterator VI_HW_HS  [V8HI  V4SI])
 (define_mode_iterator VI_HW_QH  [V16QI V8HI])
 
@@ -2876,12 +2877,12 @@
      (use (match_dup 2))])]
   "TARGET_VX"
 {
-  static char p[4][16] =
+  static const char p[4][16] =
     { { 1,  0,  3,  2,  5,  4,  7, 6, 9,  8,  11, 10, 13, 12, 15, 14 },   /* H */
       { 3,  2,  1,  0,  7,  6,  5, 4, 11, 10, 9,  8,  15, 14, 13, 12 },   /* S */
       { 7,  6,  5,  4,  3,  2,  1, 0, 15, 14, 13, 12, 11, 10, 9,  8  },   /* D */
       { 15, 14, 13, 12, 11, 10, 9, 8, 7,  6,  5,  4,  3,  2,  1,  0  } }; /* T */
-  char *perm;
+  const char *perm;
   rtx perm_rtx[16];
 
   switch (GET_MODE_SIZE (GET_MODE_INNER (<MODE>mode)))
@@ -2933,8 +2934,8 @@
   "TARGET_VXE2"
   "@
    #
-   vlbr<bhfgq>\t%v0,%v1
-   vstbr<bhfgq>\t%v1,%v0"
+   vlbr<bhfgq>\t%v0,%1
+   vstbr<bhfgq>\t%v1,%0"
   "&& reload_completed
    && !memory_operand (operands[0], <MODE>mode)
    && !memory_operand (operands[1], <MODE>mode)"
@@ -2947,6 +2948,13 @@
   ""
   [(set_attr "op_type"      "*,VRX,VRX")])
 
+(define_insn "*vstbr<mode>"
+  [(set (match_operand:VI_HW_HSDT                   0 "memory_operand"  "=R")
+	(bswap:VI_HW_HSDT (match_operand:VI_HW_HSDT 1 "register_operand" "v")))]
+  "TARGET_VXE2"
+  "vstbr<bhfgq>\t%v1,%0"
+  [(set_attr "op_type" "VRX")])
+
 ;
 ; Implement len_load/len_store optabs with vll/vstl.
 (define_expand "len_load_v16qi"