tcg: Add generic vector ops for constant shifts

Opcodes are added for scalar and vector shifts, but considering the
varied semantics of these do not expose them to the front ends.  Do
go ahead and provide them in case they are needed for backend expansion.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 45 insertions, 0 deletions

diff --git a/tcg/tcg-op-vec.c b/tcg/tcg-op-vec.c
index ac5b69ccf6..6f3060325e 100644
--- a/tcg/tcg-op-vec.c
+++ b/tcg/tcg-op-vec.c
@@ -297,3 +297,48 @@ void tcg_gen_neg_vec(unsigned vece, TCGv_vec r, TCGv_vec a)
         tcg_temp_free_vec(t);
     }
 }
+
+static void do_shifti(TCGOpcode opc, unsigned vece,
+                      TCGv_vec r, TCGv_vec a, int64_t i)
+{
+    TCGTemp *rt = tcgv_vec_temp(r);
+    TCGTemp *at = tcgv_vec_temp(a);
+    TCGArg ri = temp_arg(rt);
+    TCGArg ai = temp_arg(at);
+    TCGType type = rt->base_type;
+    int can;
+
+    tcg_debug_assert(at->base_type == type);
+    tcg_debug_assert(i >= 0 && i < (8 << vece));
+
+    if (i == 0) {
+        tcg_gen_mov_vec(r, a);
+        return;
+    }
+
+    can = tcg_can_emit_vec_op(opc, type, vece);
+    if (can > 0) {
+        vec_gen_3(opc, type, vece, ri, ai, i);
+    } else {
+        /* We leave the choice of expansion via scalar or vector shift
+           to the target.  Often, but not always, dupi can feed a vector
+           shift easier than a scalar.  */
+        tcg_debug_assert(can < 0);
+        tcg_expand_vec_op(opc, type, vece, ri, ai, i);
+    }
+}
+
+void tcg_gen_shli_vec(unsigned vece, TCGv_vec r, TCGv_vec a, int64_t i)
+{
+    do_shifti(INDEX_op_shli_vec, vece, r, a, i);
+}
+
+void tcg_gen_shri_vec(unsigned vece, TCGv_vec r, TCGv_vec a, int64_t i)
+{
+    do_shifti(INDEX_op_shri_vec, vece, r, a, i);
+}
+
+void tcg_gen_sari_vec(unsigned vece, TCGv_vec r, TCGv_vec a, int64_t i)
+{
+    do_shifti(INDEX_op_sari_vec, vece, r, a, i);
+}