target/riscv: add vector stride load and store instructions

Vector strided operations access the first memory element at the base address,
and then access subsequent elements at address increments given by the byte
offset contained in the x register specified by rs2.

Vector unit-stride operations access elements stored contiguously in memory
starting from the base effective address. It can been seen as a special
case of strided operations.

Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20200701152549.1218-7-zhiwei_liu@c-sky.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index cacb9b9cd3..9632e79cf3 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -61,6 +61,7 @@ typedef struct DisasContext {
     uint8_t lmul;
     uint8_t sew;
     uint16_t vlen;
+    uint16_t mlen;
     bool vl_eq_vlmax;
 } DisasContext;
 
@@ -548,6 +549,11 @@ static void decode_RV32_64C(DisasContext *ctx, uint16_t opcode)
     }
 }
 
+static int ex_plus_1(DisasContext *ctx, int nf)
+{
+    return nf + 1;
+}
+
 #define EX_SH(amount) \
     static int ex_shift_##amount(DisasContext *ctx, int imm) \
     {                                         \
@@ -785,6 +791,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->vill = FIELD_EX32(tb_flags, TB_FLAGS, VILL);
     ctx->sew = FIELD_EX32(tb_flags, TB_FLAGS, SEW);
     ctx->lmul = FIELD_EX32(tb_flags, TB_FLAGS, LMUL);
+    ctx->mlen = 1 << (ctx->sew  + 3 - ctx->lmul);
     ctx->vl_eq_vlmax = FIELD_EX32(tb_flags, TB_FLAGS, VL_EQ_VLMAX);
 }