From 741f117d9ac1a1a8deabc5f9b575308e88ad5fb3 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 24 Apr 2014 02:56:44 +0000 Subject: [PATCH] tcg-mips: Improve add2/sub2 Reduce insn count from 5 to either 3 or 4. Reviewed-by: Paolo Bonzini Signed-off-by: Richard Henderson --- tcg/mips/tcg-target.c | 87 ++++++++++++++++++++++++++++--------------- 1 file changed, 56 insertions(+), 31 deletions(-) diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c index 516c2b71ba..76a78527bc 100644 --- a/tcg/mips/tcg-target.c +++ b/tcg/mips/tcg-target.c @@ -1297,6 +1297,52 @@ static void tcg_out_qemu_st_direct(TCGContext *s, TCGReg datalo, TCGReg datahi, } } +static void tcg_out_addsub2(TCGContext *s, TCGReg rl, TCGReg rh, TCGReg al, + TCGReg ah, TCGArg bl, TCGArg bh, bool cbl, + bool cbh, bool is_sub) +{ + TCGReg th = TCG_TMP1; + + /* If we have a negative constant such that negating it would + make the high part zero, we can (usually) eliminate one insn. */ + if (cbl && cbh && bh == -1 && bl != 0) { + bl = -bl; + bh = 0; + is_sub = !is_sub; + } + + /* By operating on the high part first, we get to use the final + carry operation to move back from the temporary. */ + if (!cbh) { + tcg_out_opc_reg(s, (is_sub ? OPC_SUBU : OPC_ADDU), th, ah, bh); + } else if (bh != 0 || ah == rl) { + tcg_out_opc_imm(s, OPC_ADDIU, th, ah, (is_sub ? -bh : bh)); + } else { + th = ah; + } + + /* Note that tcg optimization should eliminate the bl == 0 case. */ + if (is_sub) { + if (cbl) { + tcg_out_opc_imm(s, OPC_SLTIU, TCG_TMP0, al, bl); + tcg_out_opc_imm(s, OPC_ADDIU, rl, al, -bl); + } else { + tcg_out_opc_reg(s, OPC_SLTU, TCG_TMP0, al, bl); + tcg_out_opc_reg(s, OPC_SUBU, rl, al, bl); + } + tcg_out_opc_reg(s, OPC_SUBU, rh, th, TCG_TMP0); + } else { + if (cbl) { + tcg_out_opc_imm(s, OPC_ADDIU, rl, al, bl); + tcg_out_opc_imm(s, OPC_SLTIU, TCG_TMP0, rl, bl); + } else { + tcg_out_opc_reg(s, OPC_ADDU, rl, al, bl); + tcg_out_opc_reg(s, OPC_SLTU, TCG_TMP0, rl, (rl == bl ? al : bl)); + } + tcg_out_opc_reg(s, OPC_ADDU, rh, th, TCG_TMP0); + } +} + static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is_64) { TCGReg addr_regl, addr_regh __attribute__((unused)); @@ -1419,21 +1465,6 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out_opc_reg(s, OPC_ADDU, a0, a1, a2); } break; - case INDEX_op_add2_i32: - if (const_args[4]) { - tcg_out_opc_imm(s, OPC_ADDIU, TCG_TMP0, a2, args[4]); - } else { - tcg_out_opc_reg(s, OPC_ADDU, TCG_TMP0, a2, args[4]); - } - tcg_out_opc_reg(s, OPC_SLTU, TCG_TMP1, TCG_TMP0, a2); - if (const_args[5]) { - tcg_out_opc_imm(s, OPC_ADDIU, a1, args[3], args[5]); - } else { - tcg_out_opc_reg(s, OPC_ADDU, a1, args[3], args[5]); - } - tcg_out_opc_reg(s, OPC_ADDU, a1, a1, TCG_TMP1); - tcg_out_mov(s, TCG_TYPE_I32, a0, TCG_TMP0); - break; case INDEX_op_sub_i32: if (c2) { tcg_out_opc_imm(s, OPC_ADDIU, a0, a1, -a2); @@ -1441,21 +1472,6 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out_opc_reg(s, OPC_SUBU, a0, a1, a2); } break; - case INDEX_op_sub2_i32: - if (const_args[4]) { - tcg_out_opc_imm(s, OPC_ADDIU, TCG_TMP0, a2, -args[4]); - } else { - tcg_out_opc_reg(s, OPC_SUBU, TCG_TMP0, a2, args[4]); - } - tcg_out_opc_reg(s, OPC_SLTU, TCG_TMP1, a2, TCG_TMP0); - if (const_args[5]) { - tcg_out_opc_imm(s, OPC_ADDIU, a1, args[3], -args[5]); - } else { - tcg_out_opc_reg(s, OPC_SUBU, a1, args[3], args[5]); - } - tcg_out_opc_reg(s, OPC_SUBU, a1, a1, TCG_TMP1); - tcg_out_mov(s, TCG_TYPE_I32, a0, TCG_TMP0); - break; case INDEX_op_mul_i32: if (use_mips32_instructions) { tcg_out_opc_reg(s, OPC_MUL, a0, a1, a2); @@ -1621,6 +1637,15 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out_qemu_st(s, args, true); break; + case INDEX_op_add2_i32: + tcg_out_addsub2(s, a0, a1, a2, args[3], args[4], args[5], + const_args[4], const_args[5], false); + break; + case INDEX_op_sub2_i32: + tcg_out_addsub2(s, a0, a1, a2, args[3], args[4], args[5], + const_args[4], const_args[5], true); + break; + case INDEX_op_mov_i32: /* Always emitted via tcg_out_mov. */ case INDEX_op_movi_i32: /* Always emitted via tcg_out_movi. */ case INDEX_op_call: /* Always emitted via tcg_out_call. */ @@ -1680,7 +1705,7 @@ static const TCGTargetOpDef mips_op_defs[] = { { INDEX_op_setcond_i32, { "r", "rZ", "rZ" } }, { INDEX_op_setcond2_i32, { "r", "rZ", "rZ", "rZ", "rZ" } }, - { INDEX_op_add2_i32, { "r", "r", "rZ", "rZ", "rJ", "rJ" } }, + { INDEX_op_add2_i32, { "r", "r", "rZ", "rZ", "rN", "rN" } }, { INDEX_op_sub2_i32, { "r", "r", "rZ", "rZ", "rN", "rN" } }, { INDEX_op_brcond2_i32, { "rZ", "rZ", "rZ", "rZ" } },