From b2e3ae9452fa55eb036739ec39c33f0782a97504 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 31 Jan 2018 13:20:07 -0800 Subject: tcg: Improve tcg_gen_muli_i32/i64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Convert multiplication by power of two to left shift. Reviewed-by: Emilio G. Cota Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson --- tcg/tcg-op.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'tcg') diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c index 3467787323..34b96d68f3 100644 --- a/tcg/tcg-op.c +++ b/tcg/tcg-op.c @@ -277,9 +277,15 @@ void tcg_gen_setcondi_i32(TCGCond cond, TCGv_i32 ret, void tcg_gen_muli_i32(TCGv_i32 ret, TCGv_i32 arg1, int32_t arg2) { - TCGv_i32 t0 = tcg_const_i32(arg2); - tcg_gen_mul_i32(ret, arg1, t0); - tcg_temp_free_i32(t0); + if (arg2 == 0) { + tcg_gen_movi_i32(ret, 0); + } else if (is_power_of_2(arg2)) { + tcg_gen_shli_i32(ret, arg1, ctz32(arg2)); + } else { + TCGv_i32 t0 = tcg_const_i32(arg2); + tcg_gen_mul_i32(ret, arg1, t0); + tcg_temp_free_i32(t0); + } } void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2) @@ -1430,9 +1436,15 @@ void tcg_gen_setcondi_i64(TCGCond cond, TCGv_i64 ret, void tcg_gen_muli_i64(TCGv_i64 ret, TCGv_i64 arg1, int64_t arg2) { - TCGv_i64 t0 = tcg_const_i64(arg2); - tcg_gen_mul_i64(ret, arg1, t0); - tcg_temp_free_i64(t0); + if (arg2 == 0) { + tcg_gen_movi_i64(ret, 0); + } else if (is_power_of_2(arg2)) { + tcg_gen_shli_i64(ret, arg1, ctz64(arg2)); + } else { + TCGv_i64 t0 = tcg_const_i64(arg2); + tcg_gen_mul_i64(ret, arg1, t0); + tcg_temp_free_i64(t0); + } } void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2) -- cgit v1.2.1