[PATCH 02/10] target/tricore: Implement CRCN insn

[Bastian Koppelmann <kbastian@mail.uni-paderborn.de>]

reported in https://gitlab.com/qemu-project/qemu/-/issues/1667

Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
---
 target/tricore/helper.h                   |  1 +
 target/tricore/op_helper.c                | 66 +++++++++++++++++++++++
 target/tricore/translate.c                |  6 +++
 target/tricore/tricore-opcodes.h          |  1 +
 tests/tcg/tricore/Makefile.softmmu-target |  1 +
 tests/tcg/tricore/asm/test_crcn.S         |  9 ++++
 6 files changed, 84 insertions(+)
 create mode 100644 tests/tcg/tricore/asm/test_crcn.S

diff --git a/target/tricore/helper.h b/target/tricore/helper.h
index 31d71eac7a..190645413a 100644
--- a/target/tricore/helper.h
+++ b/target/tricore/helper.h
@@ -134,6 +134,7 @@ DEF_HELPER_FLAGS_5(mulr_h, TCG_CALL_NO_RWG_SE, i32, i32, i32, i32, i32, i32)
 DEF_HELPER_FLAGS_2(crc32b, TCG_CALL_NO_RWG_SE, i32, i32, i32)
 DEF_HELPER_FLAGS_2(crc32_be, TCG_CALL_NO_RWG_SE, i32, i32, i32)
 DEF_HELPER_FLAGS_2(crc32_le, TCG_CALL_NO_RWG_SE, i32, i32, i32)
+DEF_HELPER_FLAGS_3(crcn, TCG_CALL_NO_RWG_SE, i32, i32, i32, i32)
 DEF_HELPER_FLAGS_2(shuffle, TCG_CALL_NO_RWG_SE, i32, i32, i32)
 /* CSA */
 DEF_HELPER_2(call, void, env, i32)
diff --git a/target/tricore/op_helper.c b/target/tricore/op_helper.c
index 89be1ed648..6445fd334b 100644
--- a/target/tricore/op_helper.c
+++ b/target/tricore/op_helper.c
@@ -2308,6 +2308,72 @@ uint32_t helper_crc32_le(uint32_t arg0, uint32_t arg1)
     return crc32(arg1, buf, 4);
 }
 
+static uint32_t crc_div(uint32_t crc_in, uint32_t data, uint32_t gen,
+                        uint32_t n, uint32_t m)
+{
+    uint32_t i;
+
+    data = data << n;
+    data = deposit32(data, m, 32 - m, 0);
+    for (i = 0; i < m; i++) {
+
+        if (crc_in & (1u << (n - 1))) {
+            crc_in <<= 1;
+            if (data & (1u << (m - 1))) {
+                crc_in++;
+            }
+            crc_in ^= gen;
+        } else {
+            crc_in <<= 1;
+            if (data & (1u << (m - 1))) {
+                crc_in++;
+            }
+        }
+        data <<= 1;
+        data = deposit32(data, m, 32 - m, 0);
+    }
+
+    return crc_in;
+}
+
+uint32_t helper_crcn(uint32_t arg0, uint32_t arg1, uint32_t arg2)
+{
+    uint32_t crc_out, crc_in;
+    uint32_t n = extract32(arg0, 12, 4) + 1;
+    uint32_t gen = extract32(arg0, 16, n);
+    uint32_t inv = extract32(arg0, 9, 1);
+    uint32_t le = extract32(arg0, 8, 1);
+    uint32_t m = extract32(arg0, 0, 3) + 1;
+    uint32_t data = extract32(arg1, 0, m);
+    uint32_t seed = extract32(arg2, 0, n);
+
+    if (le == 1) {
+        if (m == 0) {
+            data = 0;
+        } else {
+            data = revbit32(data) >> (32 - m);
+        }
+    }
+
+    if (inv == 1) {
+        seed = ~seed;
+    }
+
+    if (m > n) {
+        crc_in = (data >> (m - n)) ^ seed;
+    } else {
+        crc_in = (data << (n - m)) ^ seed;
+    }
+
+    crc_out = crc_div(crc_in, data, gen, n, m);
+
+    if (inv) {
+        crc_out = ~crc_out;
+    }
+
+    return deposit32(crc_out, n, 32 - n, 0);
+}
+
 uint32_t helper_shuffle(uint32_t arg0, uint32_t arg1)
 {
     uint32_t resb;
diff --git a/target/tricore/translate.c b/target/tricore/translate.c
index 1947733870..bb7dad75d6 100644
--- a/target/tricore/translate.c
+++ b/target/tricore/translate.c
@@ -6673,6 +6673,12 @@ static void decode_rrr_divide(DisasContext *ctx)
         gen_helper_pack(cpu_gpr_d[r4], cpu_PSW_C, cpu_gpr_d[r3],
                         cpu_gpr_d[r3+1], cpu_gpr_d[r1]);
         break;
+    case OPC2_32_RRR_CRCN:
+        if (has_feature(ctx, TRICORE_FEATURE_162)) {
+            gen_helper_crcn(cpu_gpr_d[r4], cpu_gpr_d[r1], cpu_gpr_d[r2],
+                            cpu_gpr_d[r3]);
+        }
+        break;
     case OPC2_32_RRR_ADD_F:
         gen_helper_fadd(cpu_gpr_d[r4], cpu_env, cpu_gpr_d[r1], cpu_gpr_d[r3]);
         break;
diff --git a/target/tricore/tricore-opcodes.h b/target/tricore/tricore-opcodes.h
index bc62b73173..f070571665 100644
--- a/target/tricore/tricore-opcodes.h
+++ b/target/tricore/tricore-opcodes.h
@@ -1247,6 +1247,7 @@ enum {
     OPC2_32_RRR_SUB_F                            = 0x03,
     OPC2_32_RRR_MADD_F                           = 0x06,
     OPC2_32_RRR_MSUB_F                           = 0x07,
+    OPC2_32_RRR_CRCN                             = 0x01, /* 1.6.2 up */
 };
 /*
  * RRR1 Format
diff --git a/tests/tcg/tricore/Makefile.softmmu-target b/tests/tcg/tricore/Makefile.softmmu-target
index f8fd207921..7a7d73a60c 100644
--- a/tests/tcg/tricore/Makefile.softmmu-target
+++ b/tests/tcg/tricore/Makefile.softmmu-target
@@ -9,6 +9,7 @@ CFLAGS = -mtc162 -c -I$(TESTS_PATH)
 TESTS += test_abs.asm.tst
 TESTS += test_bmerge.asm.tst
 TESTS += test_clz.asm.tst
+TESTS += test_crcn.asm.tst
 TESTS += test_dextr.asm.tst
 TESTS += test_dvstep.asm.tst
 TESTS += test_fadd.asm.tst
diff --git a/tests/tcg/tricore/asm/test_crcn.S b/tests/tcg/tricore/asm/test_crcn.S
new file mode 100644
index 0000000000..51a22722a3
--- /dev/null
+++ b/tests/tcg/tricore/asm/test_crcn.S
@@ -0,0 +1,9 @@
+#include "macros.h"
+.text
+.global _start
+_start:
+#                insn num    result   rs1    rs2     rs3
+#                 |     |      |      |       |       |
+    TEST_D_DDD(crcn, 1, 0x00002bed, 0x0, 0xa10ddeed, 0x0)
+
+    TEST_PASSFAIL
-- 
2.41.0