[RFC 05/10] target/riscv: rvb: add crossbar permutation instructions

[Eric Tang <tangxingxin1008@gmail.com>]

Signed-off-by: Eric Tang <tangxingxin1008@gmail.com>

diff --git a/target/riscv/bitmanip_helper.c b/target/riscv/bitmanip_helper.c
index 19c64756c5..fa4597b44b 100644
--- a/target/riscv/bitmanip_helper.c
+++ b/target/riscv/bitmanip_helper.c
@@ -205,3 +205,43 @@ target_ulong HELPER(unshflw)(target_ulong rs1, target_ulong rs2)
 {
     return do_unshfl(rs1, rs2, 32);
 }
+
+static target_ulong do_xperm(target_ulong rs1,
+                             target_ulong rs2,
+                             int sz_log2,
+                             int bits)
+{
+    target_ulong pos = 0;
+    target_ulong r = 0;
+    target_ulong sz = 1LL << sz_log2;
+    target_ulong mask = (1LL << sz) - 1;
+    int i;
+    for (i = 0; i < bits; i += sz) {
+        pos = ((rs2 >> i) & mask) << sz_log2;
+        if (pos < bits) {
+            r |= ((rs1 >> pos) & mask) << i;
+        }
+    }
+
+    return r;
+}
+
+target_ulong HELPER(xperm_n)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 2, TARGET_LONG_BITS);
+}
+
+target_ulong HELPER(xperm_b)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 3, TARGET_LONG_BITS);
+}
+
+target_ulong HELPER(xperm_h)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 4, TARGET_LONG_BITS);
+}
+
+target_ulong HELPER(xperm_w)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 5, TARGET_LONG_BITS);
+}
diff --git a/target/riscv/helper.h b/target/riscv/helper.h
index 015526faf0..ac57982e4f 100644
--- a/target/riscv/helper.h
+++ b/target/riscv/helper.h
@@ -70,6 +70,10 @@ DEF_HELPER_FLAGS_2(shfl, TCG_CALL_NO_RWG_SE, tl, tl, tl)
 DEF_HELPER_FLAGS_2(unshfl, TCG_CALL_NO_RWG_SE, tl, tl, tl)
 DEF_HELPER_FLAGS_2(shflw, TCG_CALL_NO_RWG_SE, tl, tl, tl)
 DEF_HELPER_FLAGS_2(unshflw, TCG_CALL_NO_RWG_SE, tl, tl, tl)
+DEF_HELPER_FLAGS_2(xperm_n, TCG_CALL_NO_RWG_SE, tl, tl, tl)
+DEF_HELPER_FLAGS_2(xperm_b, TCG_CALL_NO_RWG_SE, tl, tl, tl)
+DEF_HELPER_FLAGS_2(xperm_h, TCG_CALL_NO_RWG_SE, tl, tl, tl)
+DEF_HELPER_FLAGS_2(xperm_w, TCG_CALL_NO_RWG_SE, tl, tl, tl)
 
 /* Special functions */
 DEF_HELPER_2(csrr, tl, env, int)
diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
index e70a38a5c6..60b56dbf95 100644
--- a/target/riscv/insn32.decode
+++ b/target/riscv/insn32.decode
@@ -699,6 +699,9 @@ clmulh     0000101 .......... 011 ..... 0110011 @r
 clmulr     0000101 .......... 010 ..... 0110011 @r
 shfl       0000100 .......... 001 ..... 0110011 @r
 unshfl     0000100 .......... 101 ..... 0110011 @r
+xperm_n    0010100 .......... 010 ..... 0110011 @r
+xperm_b    0010100 .......... 100 ..... 0110011 @r
+xperm_h    0010100 .......... 110 ..... 0110011 @r
 cmix       .....11 .......... 001 ..... 0110011 @r4
 cmov       .....11 .......... 101 ..... 0110011 @r4
 
@@ -737,6 +740,7 @@ sh3add_uw  0010000 .......... 110 ..... 0111011 @r
 add_uw     0000100 .......... 000 ..... 0111011 @r
 shflw      0000100 .......... 001 ..... 0111011 @r
 unshflw    0000100 .......... 101 ..... 0111011 @r
+xperm_w    0010100 .......... 000 ..... 0110011 @r
 
 bsetiw     0010100 .......... 001 ..... 0011011 @sh5
 bclriw     0100100 .......... 001 ..... 0011011 @sh5
diff --git a/target/riscv/insn_trans/trans_rvb.c.inc b/target/riscv/insn_trans/trans_rvb.c.inc
index cbd48b4c8c..e869d82c8f 100644
--- a/target/riscv/insn_trans/trans_rvb.c.inc
+++ b/target/riscv/insn_trans/trans_rvb.c.inc
@@ -351,6 +351,24 @@ static bool trans_unshfli(DisasContext *ctx, arg_unshfli *a)
     return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_helper_unshfl);
 }
 
+static bool trans_xperm_n(DisasContext *ctx, arg_xperm_n *a)
+{
+    REQUIRE_EXT(ctx, RVB);
+    return gen_arith(ctx, a, EXT_NONE, gen_helper_xperm_n);
+}
+
+static bool trans_xperm_b(DisasContext *ctx, arg_xperm_b *a)
+{
+    REQUIRE_EXT(ctx, RVB);
+    return gen_arith(ctx, a, EXT_NONE, gen_helper_xperm_b);
+}
+
+static bool trans_xperm_h(DisasContext *ctx, arg_xperm_h *a)
+{
+    REQUIRE_EXT(ctx, RVB);
+    return gen_arith(ctx, a, EXT_NONE, gen_helper_xperm_h);
+}
+
 #define GEN_TRANS_CLMUL(NAME)                               \
 static bool trans_##NAME(DisasContext *ctx, arg_##NAME * a) \
 {                                                           \
@@ -749,3 +767,11 @@ static bool trans_unshflw(DisasContext *ctx, arg_unshflw *a)
     ctx->w = true;
     return gen_arith(ctx, a, EXT_ZERO, gen_helper_unshflw);
 }
+
+static bool trans_xperm_w(DisasContext *ctx, arg_xperm_w *a)
+{
+    REQUIRE_64BIT(ctx);
+    REQUIRE_EXT(ctx, RVB);
+    ctx->w = true;
+    return gen_arith(ctx, a, EXT_NONE, gen_helper_xperm_w);
+}
-- 
2.17.1