From bf0718c59a4b27dd01346a7b5b9a183ed1b18fb7 Mon Sep 17 00:00:00 2001 From: Stefan Markovic Date: Thu, 2 Aug 2018 16:15:54 +0200 Subject: [PATCH] target/mips: Add emulation of nanoMIPS 16-bit save and restore instructions Add emulation of SAVE16 and RESTORE.JRC16 instructions. Routines gen_save(), gen_restore(), and gen_adjust_sp() are provided to support this feature. This patch at the same time provides function gen_op_addr_addi(). This function will be used in emulation of some other nanoMIPS instructions. Reviewed-by: Richard Henderson Signed-off-by: Yongbok Kim Signed-off-by: Aleksandar Markovic Signed-off-by: Stefan Markovic --- target/mips/translate.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) diff --git a/target/mips/translate.c b/target/mips/translate.c index 75f2b64956..cf3254bb4a 100644 --- a/target/mips/translate.c +++ b/target/mips/translate.c @@ -1746,6 +1746,18 @@ static inline void gen_op_addr_add (DisasContext *ctx, TCGv ret, TCGv arg0, TCGv #endif } +static inline void gen_op_addr_addi(DisasContext *ctx, TCGv ret, TCGv base, + target_long ofs) +{ + tcg_gen_addi_tl(ret, base, ofs); + +#if defined(TARGET_MIPS64) + if (ctx->hflags & MIPS_HFLAG_AWRAP) { + tcg_gen_ext32s_i64(ret, ret); + } +#endif +} + /* Addresses computation (translation time) */ static target_long addr_add(DisasContext *ctx, target_long base, target_long offset) @@ -16770,6 +16782,62 @@ static inline int decode_gpr_gpr4_zero(int r) #define NANOMIPS_EXTRACT_RS5(op) (op & 0x1f) +static void gen_adjust_sp(DisasContext *ctx, int u) +{ + gen_op_addr_addi(ctx, cpu_gpr[29], cpu_gpr[29], u); +} + +static void gen_save(DisasContext *ctx, uint8_t rt, uint8_t count, + uint8_t gp, uint16_t u) +{ + int counter = 0; + TCGv va = tcg_temp_new(); + TCGv t0 = tcg_temp_new(); + + while (counter != count) { + bool use_gp = gp && (counter == count - 1); + int this_rt = use_gp ? 28 : (rt & 0x10) | ((rt + counter) & 0x1f); + int this_offset = -((counter + 1) << 2); + gen_base_offset_addr(ctx, va, 29, this_offset); + gen_load_gpr(t0, this_rt); + tcg_gen_qemu_st_tl(t0, va, ctx->mem_idx, + (MO_TEUL | ctx->default_tcg_memop_mask)); + counter++; + } + + /* adjust stack pointer */ + gen_adjust_sp(ctx, -u); + + tcg_temp_free(t0); + tcg_temp_free(va); +} + +static void gen_restore(DisasContext *ctx, uint8_t rt, uint8_t count, + uint8_t gp, uint16_t u) +{ + int counter = 0; + TCGv va = tcg_temp_new(); + TCGv t0 = tcg_temp_new(); + + while (counter != count) { + bool use_gp = gp && (counter == count - 1); + int this_rt = use_gp ? 28 : (rt & 0x10) | ((rt + counter) & 0x1f); + int this_offset = u - ((counter + 1) << 2); + gen_base_offset_addr(ctx, va, 29, this_offset); + tcg_gen_qemu_ld_tl(t0, va, ctx->mem_idx, MO_TESL | + ctx->default_tcg_memop_mask); + tcg_gen_ext32s_tl(t0, t0); + gen_store_gpr(t0, this_rt); + counter++; + } + + /* adjust stack pointer */ + gen_adjust_sp(ctx, u); + + tcg_temp_free(t0); + tcg_temp_free(va); +} + static void gen_pool16c_nanomips_insn(DisasContext *ctx) { int rt = decode_gpr_gpr3(NANOMIPS_EXTRACT_RD(ctx->opcode)); @@ -17087,6 +17155,21 @@ static int decode_nanomips_opc(CPUMIPSState *env, DisasContext *ctx) } break; case NM_P16_SR: + { + int count = extract32(ctx->opcode, 0, 4); + int u = extract32(ctx->opcode, 4, 4) << 4; + + rt = 30 + extract32(ctx->opcode, 9, 1); + switch (extract32(ctx->opcode, 8, 1)) { + case NM_SAVE16: + gen_save(ctx, rt, count, 0, u); + break; + case NM_RESTORE_JRC16: + gen_restore(ctx, rt, count, 0, u); + gen_compute_branch_nm(ctx, OPC_JR, 2, 31, 0, 0); + break; + } + } break; case NM_MOVEP: break; -- 2.11.0