From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59673) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fpH3E-0005ZJ-1g for qemu-devel@nongnu.org; Mon, 13 Aug 2018 13:54:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fpH36-00078n-Hd for qemu-devel@nongnu.org; Mon, 13 Aug 2018 13:54:43 -0400 Received: from mx2.rt-rk.com ([89.216.37.149]:55788 helo=mail.rt-rk.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fpH35-000762-Im for qemu-devel@nongnu.org; Mon, 13 Aug 2018 13:54:36 -0400 From: Aleksandar Markovic Date: Mon, 13 Aug 2018 19:53:08 +0200 Message-Id: <1534182832-554-44-git-send-email-aleksandar.markovic@rt-rk.com> In-Reply-To: <1534182832-554-1-git-send-email-aleksandar.markovic@rt-rk.com> References: <1534182832-554-1-git-send-email-aleksandar.markovic@rt-rk.com> Subject: [Qemu-devel] [PATCH v8 43/87] target/mips: Add emulation of nanoMIPS 32-bit branch instructions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, laurent@vivier.eu, riku.voipio@iki.fi, philippe.mathieu.daude@gmail.com, aurelien@aurel32.net, richard.henderson@linaro.org, amarkovic@wavecomp.com, smarkovic@wavecomp.com, pjovanovic@wavecomp.com, pburton@wavecomp.com From: Yongbok Kim Add emulation of various flavors of nanoMIPS 32-bit branch instructions. Reviewed-by: Aleksandar Markovic Signed-off-by: Yongbok Kim Signed-off-by: Aleksandar Markovic Signed-off-by: Stefan Markovic --- target/mips/translate.c | 262 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 262 insertions(+) diff --git a/target/mips/translate.c b/target/mips/translate.c index 70785f2..632fac5 100644 --- a/target/mips/translate.c +++ b/target/mips/translate.c @@ -17110,6 +17110,155 @@ static void gen_pool32axf_nanomips_insn(CPUMIPSState *env, DisasContext *ctx) } } +/* Immediate Value Compact Branches */ +static void gen_compute_imm_branch(DisasContext *ctx, uint32_t opc, + int rt, int32_t imm, int32_t offset) +{ + TCGCond cond; + int bcond_compute = 0; + TCGv t0 = tcg_temp_new(); + TCGv t1 = tcg_temp_new(); + + if (ctx->hflags & MIPS_HFLAG_BMASK) { +#ifdef MIPS_DEBUG_DISAS + LOG_DISAS("Branch in delay / forbidden slot at PC 0x" TARGET_FMT_lx + "\n", ctx->base.pc_next); +#endif + generate_exception_end(ctx, EXCP_RI); + goto out; + } + + gen_load_gpr(t0, rt); + tcg_gen_movi_tl(t1, imm); + ctx->btarget = addr_add(ctx, ctx->base.pc_next + 4, offset); + + /* Load needed operands and calculate btarget */ + switch (opc) { + case NM_BEQIC: + if (rt == 0 && imm == 0) { + /* Unconditional branch */ + } else if (rt == 0 && imm != 0) { + /* Treat as NOP */ + goto out; + } else { + bcond_compute = 1; + cond = TCG_COND_EQ; + } + break; + case NM_BBEQZC: + case NM_BBNEZC: + if (imm >= 32 && !(ctx->hflags & MIPS_HFLAG_64)) { + generate_exception_end(ctx, EXCP_RI); + goto out; + } else if (rt == 0 && opc == NM_BBEQZC) { + /* Unconditional branch */ + } else if (rt == 0 && opc == NM_BBNEZC) { + /* Treat as NOP */ + goto out; + } else { + tcg_gen_shri_tl(t0, t0, imm); + tcg_gen_andi_tl(t0, t0, 1); + tcg_gen_movi_tl(t1, 0); + bcond_compute = 1; + if (opc == NM_BBEQZC) { + cond = TCG_COND_EQ; + } else { + cond = TCG_COND_NE; + } + } + break; + case NM_BNEIC: + if (rt == 0 && imm == 0) { + /* Treat as NOP */ + goto out; + } else if (rt == 0 && imm != 0) { + /* Unconditional branch */ + } else { + bcond_compute = 1; + cond = TCG_COND_NE; + } + break; + case NM_BGEIC: + if (rt == 0 && imm == 0) { + /* Unconditional branch */ + } else { + bcond_compute = 1; + cond = TCG_COND_GE; + } + break; + case NM_BLTIC: + bcond_compute = 1; + cond = TCG_COND_LT; + break; + case NM_BGEIUC: + if (rt == 0 && imm == 0) { + /* Unconditional branch */ + } else { + bcond_compute = 1; + cond = TCG_COND_GEU; + } + break; + case NM_BLTIUC: + bcond_compute = 1; + cond = TCG_COND_LTU; + break; + default: + MIPS_INVAL("Immediate Value Compact branch"); + generate_exception_end(ctx, EXCP_RI); + goto out; + } + + if (bcond_compute == 0) { + /* Uncoditional compact branch */ + ctx->hflags |= MIPS_HFLAG_B; + /* Generating branch here as compact branches don't have delay slot */ + gen_branch(ctx, 4); + } else { + /* Conditional compact branch */ + TCGLabel *fs = gen_new_label(); + save_cpu_state(ctx, 0); + + tcg_gen_brcond_tl(tcg_invert_cond(cond), t0, t1, fs); + + /* Generating branch here as compact branches don't have delay slot */ + gen_goto_tb(ctx, 1, ctx->btarget); + gen_set_label(fs); + + ctx->hflags |= MIPS_HFLAG_FBNSLOT; + } + +out: + tcg_temp_free(t0); + tcg_temp_free(t1); +} + +/* P.BALRSC type nanoMIPS R6 branches: BALRSC and BRSC */ +static void gen_compute_nanomips_pbalrsc_branch(DisasContext *ctx, int rs, + int rt) +{ + TCGv t0 = tcg_temp_new(); + TCGv t1 = tcg_temp_new(); + + /* load rs */ + gen_load_gpr(t0, rs); + + /* link */ + if (rt != 0) { + tcg_gen_movi_tl(cpu_gpr[rt], ctx->base.pc_next + 4); + } + + /* calculate btarget */ + tcg_gen_shli_tl(t0, t0, 1); + tcg_gen_movi_tl(t1, ctx->base.pc_next + 4); + gen_op_addr_add(ctx, btarget, t1, t0); + + ctx->hflags |= MIPS_HFLAG_BR; + /* Generating branch here as compact branches don't have delay slot */ + gen_branch(ctx, 4); + + tcg_temp_free(t0); + tcg_temp_free(t1); +} static void gen_p_lsx(DisasContext *ctx, int rd, int rs, int rt) { @@ -18171,16 +18320,129 @@ static int decode_nanomips_32_48_opc(CPUMIPSState *env, DisasContext *ctx) } break; case NM_MOVE_BALC: + { + TCGv t0 = tcg_temp_new(); + int32_t s = sextract32(ctx->opcode, 0, 1) << 21 | + extract32(ctx->opcode, 1, 20) << 1; + rd = (extract32(ctx->opcode, 24, 1)) == 0 ? 4 : 5; + rt = decode_gpr_gpr4_zero(extract32(ctx->opcode, 25, 1) << 3 | + extract32(ctx->opcode, 21, 3)); + gen_load_gpr(t0, rt); + tcg_gen_mov_tl(cpu_gpr[rd], t0); + gen_compute_branch(ctx, OPC_BGEZAL, 4, 0, 0, s, 0); + tcg_temp_free(t0); + } break; case NM_P_BAL: + { + int32_t s = sextract32(ctx->opcode, 0, 1) << 25 | + extract32(ctx->opcode, 1, 24) << 1; + + if ((extract32(ctx->opcode, 25, 1)) == 0) { + /* BC */ + gen_compute_branch(ctx, OPC_BEQ, 4, 0, 0, s, 0); + } else { + /* BALC */ + gen_compute_branch(ctx, OPC_BGEZAL, 4, 0, 0, s, 0); + } + } break; case NM_P_J: + switch (extract32(ctx->opcode, 12, 4)) { + case NM_JALRC: + case NM_JALRC_HB: + gen_compute_branch(ctx, OPC_JALR, 4, rs, rt, 0, 0); + break; + case NM_P_BALRSC: + gen_compute_nanomips_pbalrsc_branch(ctx, rs, rt); + break; + default: + generate_exception_end(ctx, EXCP_RI); + break; + } break; case NM_P_BR1: + { + int32_t s = sextract32(ctx->opcode, 0, 1) << 14 | + extract32(ctx->opcode, 1, 13) << 1; + switch (extract32(ctx->opcode, 14, 2)) { + case NM_BEQC: + gen_compute_branch(ctx, OPC_BEQ, 4, rs, rt, s, 0); + break; + case NM_P_BR3A: + s = sextract32(ctx->opcode, 0, 1) << 14 | + extract32(ctx->opcode, 1, 13) << 1; + check_cp1_enabled(ctx); + switch (extract32(ctx->opcode, 16, 5)) { + case NM_BC1EQZC: + gen_compute_branch1_r6(ctx, OPC_BC1EQZ, rt, s, 0); + break; + case NM_BC1NEZC: + gen_compute_branch1_r6(ctx, OPC_BC1NEZ, rt, s, 0); + break; + default: + generate_exception_end(ctx, EXCP_RI); + break; + } + break; + case NM_BGEC: + if (rs == rt) { + gen_compute_compact_branch(ctx, OPC_BC, rs, rt, s); + } else { + gen_compute_compact_branch(ctx, OPC_BGEC, rs, rt, s); + } + break; + case NM_BGEUC: + if (rs == rt || rt == 0) { + gen_compute_compact_branch(ctx, OPC_BC, 0, 0, s); + } else if (rs == 0) { + gen_compute_compact_branch(ctx, OPC_BEQZC, rt, 0, s); + } else { + gen_compute_compact_branch(ctx, OPC_BGEUC, rs, rt, s); + } + break; + } + } break; case NM_P_BR2: + { + int32_t s = sextract32(ctx->opcode, 0, 1) << 14 | + extract32(ctx->opcode, 1, 13) << 1; + switch (extract32(ctx->opcode, 14, 2)) { + case NM_BNEC: + gen_compute_branch(ctx, OPC_BNE, 4, rs, rt, s, 0); + break; + case NM_BLTC: + if (rs != 0 && rt != 0 && rs == rt) { + /* NOP */ + ctx->hflags |= MIPS_HFLAG_FBNSLOT; + } else { + gen_compute_compact_branch(ctx, OPC_BLTC, rs, rt, s); + } + break; + case NM_BLTUC: + if (rs == 0 || rs == rt) { + /* NOP */ + ctx->hflags |= MIPS_HFLAG_FBNSLOT; + } else { + gen_compute_compact_branch(ctx, OPC_BLTUC, rs, rt, s); + } + break; + default: + generate_exception_end(ctx, EXCP_RI); + break; + } + } break; case NM_P_BRI: + { + int32_t s = sextract32(ctx->opcode, 0, 1) << 11 | + extract32(ctx->opcode, 1, 10) << 1; + uint32_t u = extract32(ctx->opcode, 11, 7); + + gen_compute_imm_branch(ctx, extract32(ctx->opcode, 18, 3), + rt, u, s); + } break; default: generate_exception_end(ctx, EXCP_RI); -- 2.7.4