[PULL 29/34] target/ppc: implement addg6s

[Daniel Henrique Barboza]

From: Matheus Ferst <matheus.ferst@eldorado.org.br>

Implements the following Power ISA v2.06 instruction:
addg6s: Add and Generate Sixes

Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Signed-off-by: Víctor Colombo <victor.colombo@eldorado.org.br>
Reviewed-by: Víctor Colombo <victor.colombo@eldorado.org.br>
Message-Id: <20220629162904.105060-10-victor.colombo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 target/ppc/insn32.decode                   |  4 +++
 target/ppc/translate/fixedpoint-impl.c.inc | 37 ++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/target/ppc/insn32.decode b/target/ppc/insn32.decode
index e5770bcc16..af8ba9ca9b 100644
--- a/target/ppc/insn32.decode
+++ b/target/ppc/insn32.decode
@@ -311,6 +311,10 @@ CNTTZDM         011111 ..... ..... ..... 1000111011 -   @X
 PDEPD           011111 ..... ..... ..... 0010011100 -   @X
 PEXTD           011111 ..... ..... ..... 0010111100 -   @X
 
+## BCD Assist
+
+ADDG6S          011111 ..... ..... ..... - 001001010 -  @X
+
 ### Float-Point Load Instructions
 
 LFS             110000 ..... ..... ................     @D
diff --git a/target/ppc/translate/fixedpoint-impl.c.inc 
b/target/ppc/translate/fixedpoint-impl.c.inc
index 1aab32be03..490e49cfc7 100644
--- a/target/ppc/translate/fixedpoint-impl.c.inc
+++ b/target/ppc/translate/fixedpoint-impl.c.inc
@@ -492,3 +492,40 @@ static bool trans_PEXTD(DisasContext *ctx, arg_X *a)
 #endif
     return true;
 }
+
+static bool trans_ADDG6S(DisasContext *ctx, arg_X *a)
+{
+    const uint64_t carry_bits = 0x1111111111111111ULL;
+    TCGv t0, t1, carry, zero = tcg_constant_tl(0);
+
+    REQUIRE_INSNS_FLAGS2(ctx, BCDA_ISA206);
+
+    t0 = tcg_temp_new();
+    t1 = tcg_const_tl(0);
+    carry = tcg_const_tl(0);
+
+    for (int i = 0; i < 16; i++) {
+        tcg_gen_shri_tl(t0, cpu_gpr[a->ra], i * 4);
+        tcg_gen_andi_tl(t0, t0, 0xf);
+        tcg_gen_add_tl(t1, t1, t0);
+
+        tcg_gen_shri_tl(t0, cpu_gpr[a->rb], i * 4);
+        tcg_gen_andi_tl(t0, t0, 0xf);
+        tcg_gen_add_tl(t1, t1, t0);
+
+        tcg_gen_andi_tl(t1, t1, 0x10);
+        tcg_gen_setcond_tl(TCG_COND_NE, t1, t1, zero);
+
+        tcg_gen_shli_tl(t0, t1, i * 4);
+        tcg_gen_or_tl(carry, carry, t0);
+    }
+
+    tcg_gen_xori_tl(carry, carry, (target_long)carry_bits);
+    tcg_gen_muli_tl(cpu_gpr[a->rt], carry, 6);
+
+    tcg_temp_free(t0);
+    tcg_temp_free(t1);
+    tcg_temp_free(carry);
+
+    return true;
+}
-- 
2.36.1