| Message ID | 1393952650-16802-7-git-send-email-rth@twiddle.net |
|---|---|
| State | New |
| Headers | show |
Richard Henderson <rth@twiddle.net> writes: > This reduces the code size of the function significantly. > > Signed-off-by: Richard Henderson <rth@twiddle.net> > --- > tcg/aarch64/tcg-target.c | 95 +++++++++++++++++++++++++----------------------- > 1 file changed, 50 insertions(+), 45 deletions(-) > > diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c > index 8f68450..dca7632 100644 > --- a/tcg/aarch64/tcg-target.c > +++ b/tcg/aarch64/tcg-target.c > @@ -1098,15 +1098,22 @@ static inline void tcg_out_load_pair(TCGContext *s, TCGReg addr, > } > > static void tcg_out_op(TCGContext *s, TCGOpcode opc, > - const TCGArg *args, const int *const_args) > + const TCGArg args[TCG_MAX_OP_ARGS], > + const int const_args[TCG_MAX_OP_ARGS]) > { > /* 99% of the time, we can signal the use of extension registers > by looking to see if the opcode handles 64-bit data. */ > TCGType ext = (tcg_op_defs[opc].flags & TCG_OPF_64BIT) != 0; > > + /* Hoist the loads of the most common arguments. */ > + TCGArg a0 = args[0]; > + TCGArg a1 = args[1]; > + TCGArg a2 = args[2]; > + int c2 = const_args[2]; > + The code certainly looks a lot cleaner but I'm not sure what this gains us. Surely the compiler should have done all this for us? But an improvement so: Reviewed-by: Alex Bennée <alex.bennee@linaro.org> > switch (opc) { > case INDEX_op_exit_tb: > - tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_X0, args[0]); > + tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_X0, a0); > tcg_out_goto(s, (tcg_target_long)tb_ret_addr); > break; > > @@ -1115,23 +1122,23 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, > #error "USE_DIRECT_JUMP required for aarch64" > #endif > assert(s->tb_jmp_offset != NULL); /* consistency for USE_DIRECT_JUMP */ > - s->tb_jmp_offset[args[0]] = s->code_ptr - s->code_buf; > + s->tb_jmp_offset[a0] = s->code_ptr - s->code_buf; > /* actual branch destination will be patched by > aarch64_tb_set_jmp_target later, beware retranslation. */ > tcg_out_goto_noaddr(s); > - s->tb_next_offset[args[0]] = s->code_ptr - s->code_buf; > + s->tb_next_offset[a0] = s->code_ptr - s->code_buf; > break; > > case INDEX_op_call: > if (const_args[0]) { > - tcg_out_call(s, args[0]); > + tcg_out_call(s, a0); > } else { > - tcg_out_callr(s, args[0]); > + tcg_out_callr(s, a0); > } > break; > > case INDEX_op_br: > - tcg_out_goto_label(s, args[0]); > + tcg_out_goto_label(s, a0); > break; > > case INDEX_op_ld_i32: > @@ -1154,97 +1161,95 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, > case INDEX_op_st16_i64: > case INDEX_op_st32_i64: > tcg_out_ldst(s, aarch64_ldst_get_data(opc), aarch64_ldst_get_type(opc), > - args[0], args[1], args[2]); > + a0, a1, a2); > break; > > case INDEX_op_add_i64: > case INDEX_op_add_i32: > - tcg_out_arith(s, ARITH_ADD, ext, args[0], args[1], args[2], 0); > + tcg_out_arith(s, ARITH_ADD, ext, a0, a1, a2, 0); > break; > > case INDEX_op_sub_i64: > case INDEX_op_sub_i32: > - tcg_out_arith(s, ARITH_SUB, ext, args[0], args[1], args[2], 0); > + tcg_out_arith(s, ARITH_SUB, ext, a0, a1, a2, 0); > break; > > case INDEX_op_and_i64: > case INDEX_op_and_i32: > - tcg_out_arith(s, ARITH_AND, ext, args[0], args[1], args[2], 0); > + tcg_out_arith(s, ARITH_AND, ext, a0, a1, a2, 0); > break; > > case INDEX_op_or_i64: > case INDEX_op_or_i32: > - tcg_out_arith(s, ARITH_OR, ext, args[0], args[1], args[2], 0); > + tcg_out_arith(s, ARITH_OR, ext, a0, a1, a2, 0); > break; > > case INDEX_op_xor_i64: > case INDEX_op_xor_i32: > - tcg_out_arith(s, ARITH_XOR, ext, args[0], args[1], args[2], 0); > + tcg_out_arith(s, ARITH_XOR, ext, a0, a1, a2, 0); > break; > > case INDEX_op_mul_i64: > case INDEX_op_mul_i32: > - tcg_out_mul(s, ext, args[0], args[1], args[2]); > + tcg_out_mul(s, ext, a0, a1, a2); > break; > > case INDEX_op_shl_i64: > case INDEX_op_shl_i32: > - if (const_args[2]) { /* LSL / UBFM Wd, Wn, (32 - m) */ > - tcg_out_shl(s, ext, args[0], args[1], args[2]); > + if (c2) { /* LSL / UBFM Wd, Wn, (32 - m) */ > + tcg_out_shl(s, ext, a0, a1, a2); > } else { /* LSL / LSLV */ > - tcg_out_shiftrot_reg(s, SRR_SHL, ext, args[0], args[1], args[2]); > + tcg_out_shiftrot_reg(s, SRR_SHL, ext, a0, a1, a2); > } > break; > > case INDEX_op_shr_i64: > case INDEX_op_shr_i32: > - if (const_args[2]) { /* LSR / UBFM Wd, Wn, m, 31 */ > - tcg_out_shr(s, ext, args[0], args[1], args[2]); > + if (c2) { /* LSR / UBFM Wd, Wn, m, 31 */ > + tcg_out_shr(s, ext, a0, a1, a2); > } else { /* LSR / LSRV */ > - tcg_out_shiftrot_reg(s, SRR_SHR, ext, args[0], args[1], args[2]); > + tcg_out_shiftrot_reg(s, SRR_SHR, ext, a0, a1, a2); > } > break; > > case INDEX_op_sar_i64: > case INDEX_op_sar_i32: > - if (const_args[2]) { /* ASR / SBFM Wd, Wn, m, 31 */ > - tcg_out_sar(s, ext, args[0], args[1], args[2]); > + if (c2) { /* ASR / SBFM Wd, Wn, m, 31 */ > + tcg_out_sar(s, ext, a0, a1, a2); > } else { /* ASR / ASRV */ > - tcg_out_shiftrot_reg(s, SRR_SAR, ext, args[0], args[1], args[2]); > + tcg_out_shiftrot_reg(s, SRR_SAR, ext, a0, a1, a2); > } > break; > > case INDEX_op_rotr_i64: > case INDEX_op_rotr_i32: > - if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, m */ > - tcg_out_rotr(s, ext, args[0], args[1], args[2]); > + if (c2) { /* ROR / EXTR Wd, Wm, Wm, m */ > + tcg_out_rotr(s, ext, a0, a1, a2); > } else { /* ROR / RORV */ > - tcg_out_shiftrot_reg(s, SRR_ROR, ext, args[0], args[1], args[2]); > + tcg_out_shiftrot_reg(s, SRR_ROR, ext, a0, a1, a2); > } > break; > > case INDEX_op_rotl_i64: > case INDEX_op_rotl_i32: /* same as rotate right by (32 - m) */ > - if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, 32 - m */ > - tcg_out_rotl(s, ext, args[0], args[1], args[2]); > + if (c2) { /* ROR / EXTR Wd, Wm, Wm, 32 - m */ > + tcg_out_rotl(s, ext, a0, a1, a2); > } else { > - tcg_out_arith(s, ARITH_SUB, 0, > - TCG_REG_TMP, TCG_REG_XZR, args[2], 0); > - tcg_out_shiftrot_reg(s, SRR_ROR, ext, > - args[0], args[1], TCG_REG_TMP); > + tcg_out_arith(s, ARITH_SUB, 0, TCG_REG_TMP, TCG_REG_XZR, a2, 0); > + tcg_out_shiftrot_reg(s, SRR_ROR, ext, a0, a1, TCG_REG_TMP); > } > break; > > case INDEX_op_brcond_i64: > - case INDEX_op_brcond_i32: /* CMP 0, 1, cond(2), label 3 */ > - tcg_out_cmp(s, ext, args[0], args[1], 0); > - tcg_out_goto_label_cond(s, args[2], args[3]); > + case INDEX_op_brcond_i32: > + tcg_out_cmp(s, ext, a0, a1, 0); > + tcg_out_goto_label_cond(s, a2, args[3]); > break; > > case INDEX_op_setcond_i64: > case INDEX_op_setcond_i32: > - tcg_out_cmp(s, ext, args[1], args[2], 0); > - tcg_out_cset(s, 0, args[0], args[3]); > + tcg_out_cmp(s, ext, a1, a2, 0); > + tcg_out_cset(s, 0, a0, args[3]); > break; > > case INDEX_op_qemu_ld8u: > @@ -1290,34 +1295,34 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, > /* FALLTHRU */ > case INDEX_op_bswap64_i64: > case INDEX_op_bswap32_i32: > - tcg_out_rev(s, ext, args[0], args[1]); > + tcg_out_rev(s, ext, a0, a1); > break; > case INDEX_op_bswap16_i64: > case INDEX_op_bswap16_i32: > - tcg_out_rev16(s, 0, args[0], args[1]); > + tcg_out_rev16(s, 0, a0, a1); > break; > > case INDEX_op_ext8s_i64: > case INDEX_op_ext8s_i32: > - tcg_out_sxt(s, ext, 0, args[0], args[1]); > + tcg_out_sxt(s, ext, 0, a0, a1); > break; > case INDEX_op_ext16s_i64: > case INDEX_op_ext16s_i32: > - tcg_out_sxt(s, ext, 1, args[0], args[1]); > + tcg_out_sxt(s, ext, 1, a0, a1); > break; > case INDEX_op_ext32s_i64: > - tcg_out_sxt(s, 1, 2, args[0], args[1]); > + tcg_out_sxt(s, 1, 2, a0, a1); > break; > case INDEX_op_ext8u_i64: > case INDEX_op_ext8u_i32: > - tcg_out_uxt(s, 0, args[0], args[1]); > + tcg_out_uxt(s, 0, a0, a1); > break; > case INDEX_op_ext16u_i64: > case INDEX_op_ext16u_i32: > - tcg_out_uxt(s, 1, args[0], args[1]); > + tcg_out_uxt(s, 1, a0, a1); > break; > case INDEX_op_ext32u_i64: > - tcg_out_movr(s, 0, args[0], args[1]); > + tcg_out_movr(s, 0, a0, a1); > break; > > case INDEX_op_mov_i64:
On 03/05/2014 04:14 AM, Alex Bennée wrote: >> > + /* Hoist the loads of the most common arguments. */ >> > + TCGArg a0 = args[0]; >> > + TCGArg a1 = args[1]; >> > + TCGArg a2 = args[2]; >> > + int c2 = const_args[2]; >> > + > The code certainly looks a lot cleaner but I'm not sure what this gains > us. Surely the compiler should have done all this for us? The compiler will only hoist stuff that's used on all following paths, not stuff that's used on most following paths. It also gains us variables in which we can manipulate the arguments before we pass them off. E.g. sign-extending 32-bit constants before entering the 64-bit path. r~
diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c index 8f68450..dca7632 100644 --- a/tcg/aarch64/tcg-target.c +++ b/tcg/aarch64/tcg-target.c @@ -1098,15 +1098,22 @@ static inline void tcg_out_load_pair(TCGContext *s, TCGReg addr, } static void tcg_out_op(TCGContext *s, TCGOpcode opc, - const TCGArg *args, const int *const_args) + const TCGArg args[TCG_MAX_OP_ARGS], + const int const_args[TCG_MAX_OP_ARGS]) { /* 99% of the time, we can signal the use of extension registers by looking to see if the opcode handles 64-bit data. */ TCGType ext = (tcg_op_defs[opc].flags & TCG_OPF_64BIT) != 0; + /* Hoist the loads of the most common arguments. */ + TCGArg a0 = args[0]; + TCGArg a1 = args[1]; + TCGArg a2 = args[2]; + int c2 = const_args[2]; + switch (opc) { case INDEX_op_exit_tb: - tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_X0, args[0]); + tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_X0, a0); tcg_out_goto(s, (tcg_target_long)tb_ret_addr); break; @@ -1115,23 +1122,23 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, #error "USE_DIRECT_JUMP required for aarch64" #endif assert(s->tb_jmp_offset != NULL); /* consistency for USE_DIRECT_JUMP */ - s->tb_jmp_offset[args[0]] = s->code_ptr - s->code_buf; + s->tb_jmp_offset[a0] = s->code_ptr - s->code_buf; /* actual branch destination will be patched by aarch64_tb_set_jmp_target later, beware retranslation. */ tcg_out_goto_noaddr(s); - s->tb_next_offset[args[0]] = s->code_ptr - s->code_buf; + s->tb_next_offset[a0] = s->code_ptr - s->code_buf; break; case INDEX_op_call: if (const_args[0]) { - tcg_out_call(s, args[0]); + tcg_out_call(s, a0); } else { - tcg_out_callr(s, args[0]); + tcg_out_callr(s, a0); } break; case INDEX_op_br: - tcg_out_goto_label(s, args[0]); + tcg_out_goto_label(s, a0); break; case INDEX_op_ld_i32: @@ -1154,97 +1161,95 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, case INDEX_op_st16_i64: case INDEX_op_st32_i64: tcg_out_ldst(s, aarch64_ldst_get_data(opc), aarch64_ldst_get_type(opc), - args[0], args[1], args[2]); + a0, a1, a2); break; case INDEX_op_add_i64: case INDEX_op_add_i32: - tcg_out_arith(s, ARITH_ADD, ext, args[0], args[1], args[2], 0); + tcg_out_arith(s, ARITH_ADD, ext, a0, a1, a2, 0); break; case INDEX_op_sub_i64: case INDEX_op_sub_i32: - tcg_out_arith(s, ARITH_SUB, ext, args[0], args[1], args[2], 0); + tcg_out_arith(s, ARITH_SUB, ext, a0, a1, a2, 0); break; case INDEX_op_and_i64: case INDEX_op_and_i32: - tcg_out_arith(s, ARITH_AND, ext, args[0], args[1], args[2], 0); + tcg_out_arith(s, ARITH_AND, ext, a0, a1, a2, 0); break; case INDEX_op_or_i64: case INDEX_op_or_i32: - tcg_out_arith(s, ARITH_OR, ext, args[0], args[1], args[2], 0); + tcg_out_arith(s, ARITH_OR, ext, a0, a1, a2, 0); break; case INDEX_op_xor_i64: case INDEX_op_xor_i32: - tcg_out_arith(s, ARITH_XOR, ext, args[0], args[1], args[2], 0); + tcg_out_arith(s, ARITH_XOR, ext, a0, a1, a2, 0); break; case INDEX_op_mul_i64: case INDEX_op_mul_i32: - tcg_out_mul(s, ext, args[0], args[1], args[2]); + tcg_out_mul(s, ext, a0, a1, a2); break; case INDEX_op_shl_i64: case INDEX_op_shl_i32: - if (const_args[2]) { /* LSL / UBFM Wd, Wn, (32 - m) */ - tcg_out_shl(s, ext, args[0], args[1], args[2]); + if (c2) { /* LSL / UBFM Wd, Wn, (32 - m) */ + tcg_out_shl(s, ext, a0, a1, a2); } else { /* LSL / LSLV */ - tcg_out_shiftrot_reg(s, SRR_SHL, ext, args[0], args[1], args[2]); + tcg_out_shiftrot_reg(s, SRR_SHL, ext, a0, a1, a2); } break; case INDEX_op_shr_i64: case INDEX_op_shr_i32: - if (const_args[2]) { /* LSR / UBFM Wd, Wn, m, 31 */ - tcg_out_shr(s, ext, args[0], args[1], args[2]); + if (c2) { /* LSR / UBFM Wd, Wn, m, 31 */ + tcg_out_shr(s, ext, a0, a1, a2); } else { /* LSR / LSRV */ - tcg_out_shiftrot_reg(s, SRR_SHR, ext, args[0], args[1], args[2]); + tcg_out_shiftrot_reg(s, SRR_SHR, ext, a0, a1, a2); } break; case INDEX_op_sar_i64: case INDEX_op_sar_i32: - if (const_args[2]) { /* ASR / SBFM Wd, Wn, m, 31 */ - tcg_out_sar(s, ext, args[0], args[1], args[2]); + if (c2) { /* ASR / SBFM Wd, Wn, m, 31 */ + tcg_out_sar(s, ext, a0, a1, a2); } else { /* ASR / ASRV */ - tcg_out_shiftrot_reg(s, SRR_SAR, ext, args[0], args[1], args[2]); + tcg_out_shiftrot_reg(s, SRR_SAR, ext, a0, a1, a2); } break; case INDEX_op_rotr_i64: case INDEX_op_rotr_i32: - if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, m */ - tcg_out_rotr(s, ext, args[0], args[1], args[2]); + if (c2) { /* ROR / EXTR Wd, Wm, Wm, m */ + tcg_out_rotr(s, ext, a0, a1, a2); } else { /* ROR / RORV */ - tcg_out_shiftrot_reg(s, SRR_ROR, ext, args[0], args[1], args[2]); + tcg_out_shiftrot_reg(s, SRR_ROR, ext, a0, a1, a2); } break; case INDEX_op_rotl_i64: case INDEX_op_rotl_i32: /* same as rotate right by (32 - m) */ - if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, 32 - m */ - tcg_out_rotl(s, ext, args[0], args[1], args[2]); + if (c2) { /* ROR / EXTR Wd, Wm, Wm, 32 - m */ + tcg_out_rotl(s, ext, a0, a1, a2); } else { - tcg_out_arith(s, ARITH_SUB, 0, - TCG_REG_TMP, TCG_REG_XZR, args[2], 0); - tcg_out_shiftrot_reg(s, SRR_ROR, ext, - args[0], args[1], TCG_REG_TMP); + tcg_out_arith(s, ARITH_SUB, 0, TCG_REG_TMP, TCG_REG_XZR, a2, 0); + tcg_out_shiftrot_reg(s, SRR_ROR, ext, a0, a1, TCG_REG_TMP); } break; case INDEX_op_brcond_i64: - case INDEX_op_brcond_i32: /* CMP 0, 1, cond(2), label 3 */ - tcg_out_cmp(s, ext, args[0], args[1], 0); - tcg_out_goto_label_cond(s, args[2], args[3]); + case INDEX_op_brcond_i32: + tcg_out_cmp(s, ext, a0, a1, 0); + tcg_out_goto_label_cond(s, a2, args[3]); break; case INDEX_op_setcond_i64: case INDEX_op_setcond_i32: - tcg_out_cmp(s, ext, args[1], args[2], 0); - tcg_out_cset(s, 0, args[0], args[3]); + tcg_out_cmp(s, ext, a1, a2, 0); + tcg_out_cset(s, 0, a0, args[3]); break; case INDEX_op_qemu_ld8u: @@ -1290,34 +1295,34 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, /* FALLTHRU */ case INDEX_op_bswap64_i64: case INDEX_op_bswap32_i32: - tcg_out_rev(s, ext, args[0], args[1]); + tcg_out_rev(s, ext, a0, a1); break; case INDEX_op_bswap16_i64: case INDEX_op_bswap16_i32: - tcg_out_rev16(s, 0, args[0], args[1]); + tcg_out_rev16(s, 0, a0, a1); break; case INDEX_op_ext8s_i64: case INDEX_op_ext8s_i32: - tcg_out_sxt(s, ext, 0, args[0], args[1]); + tcg_out_sxt(s, ext, 0, a0, a1); break; case INDEX_op_ext16s_i64: case INDEX_op_ext16s_i32: - tcg_out_sxt(s, ext, 1, args[0], args[1]); + tcg_out_sxt(s, ext, 1, a0, a1); break; case INDEX_op_ext32s_i64: - tcg_out_sxt(s, 1, 2, args[0], args[1]); + tcg_out_sxt(s, 1, 2, a0, a1); break; case INDEX_op_ext8u_i64: case INDEX_op_ext8u_i32: - tcg_out_uxt(s, 0, args[0], args[1]); + tcg_out_uxt(s, 0, a0, a1); break; case INDEX_op_ext16u_i64: case INDEX_op_ext16u_i32: - tcg_out_uxt(s, 1, args[0], args[1]); + tcg_out_uxt(s, 1, a0, a1); break; case INDEX_op_ext32u_i64: - tcg_out_movr(s, 0, args[0], args[1]); + tcg_out_movr(s, 0, a0, a1); break; case INDEX_op_mov_i64:
This reduces the code size of the function significantly. Signed-off-by: Richard Henderson <rth@twiddle.net> --- tcg/aarch64/tcg-target.c | 95 +++++++++++++++++++++++++----------------------- 1 file changed, 50 insertions(+), 45 deletions(-)