diff options
| author | Richard Henderson <rth@twiddle.net> | 2012-10-02 11:32:30 -0700 |
|---|---|---|
| committer | Aurelien Jarno <aurelien@aurel32.net> | 2012-10-17 17:51:39 +0200 |
| commit | 1414968a6aecd23cb037bc9e718d6f05ead2afaf (patch) | |
| tree | 4dc9f46337e135d3bece03959b6cb3bdc0e8d921 /tcg/optimize.c | |
| parent | 1305c451e67e3def030720013415103f5e0f5e11 (diff) | |
| download | focaccia-qemu-1414968a6aecd23cb037bc9e718d6f05ead2afaf.tar.gz focaccia-qemu-1414968a6aecd23cb037bc9e718d6f05ead2afaf.zip | |
tcg: Optimize mulu2
Like add2, do operand ordering, constant folding, and dead operand elimination. The latter happens about 15% of all mulu2 during an x86_64 bios boot. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Diffstat (limited to 'tcg/optimize.c')
| -rw-r--r-- | tcg/optimize.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index 05891ef380..a06c8eb43e 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -543,6 +543,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, swap_commutative(args[0], &args[2], &args[4]); swap_commutative(args[1], &args[3], &args[5]); break; + case INDEX_op_mulu2_i32: + swap_commutative(args[0], &args[2], &args[3]); + break; case INDEX_op_brcond2_i32: if (swap_commutative2(&args[0], &args[2])) { args[4] = tcg_swap_cond(args[4]); @@ -831,6 +834,29 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, } goto do_default; + case INDEX_op_mulu2_i32: + if (temps[args[2]].state == TCG_TEMP_CONST + && temps[args[3]].state == TCG_TEMP_CONST) { + uint32_t a = temps[args[2]].val; + uint32_t b = temps[args[3]].val; + uint64_t r = (uint64_t)a * b; + TCGArg rl, rh; + + /* We emit the extra nop when we emit the mulu2. */ + assert(gen_opc_buf[op_index + 1] == INDEX_op_nop); + + rl = args[0]; + rh = args[1]; + gen_opc_buf[op_index] = INDEX_op_movi_i32; + gen_opc_buf[++op_index] = INDEX_op_movi_i32; + tcg_opt_gen_movi(&gen_args[0], rl, (uint32_t)r); + tcg_opt_gen_movi(&gen_args[2], rh, (uint32_t)(r >> 32)); + gen_args += 4; + args += 4; + break; + } + goto do_default; + case INDEX_op_brcond2_i32: tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]); if (tmp != 2) { |