[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH 4/7] tcg: Optimize double-word comparisons against z
From: |
Richard Henderson |
Subject: |
[Qemu-devel] [PATCH 4/7] tcg: Optimize double-word comparisons against zero |
Date: |
Thu, 27 Sep 2012 10:19:54 -0700 |
Signed-off-by: Richard Henderson <address@hidden>
---
tcg/optimize.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)
diff --git a/tcg/optimize.c b/tcg/optimize.c
index d39926e..c972e4f 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -799,6 +799,57 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
uint16_t *tcg_opc_ptr,
}
args += 6;
break;
+ case INDEX_op_brcond2_i32:
+ /* Simplify LT/GE comparisons vs zero to a single compare
+ vs the high word of the input. */
+ if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE)
+ && temps[args[2]].state == TCG_TEMP_CONST
+ && temps[args[3]].state == TCG_TEMP_CONST
+ && temps[args[2]].val == 0
+ && temps[args[2]].val == 0) {
+ gen_opc_buf[op_index] = INDEX_op_brcond_i32;
+ args[0] = args[1];
+ args[1] = args[3];
+ args[2] = args[4];
+ args[3] = args[5];
+ gen_args += 4;
+ } else {
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args[3] = args[3];
+ gen_args[4] = args[4];
+ gen_args[5] = args[5];
+ gen_args += 6;
+ }
+ memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+ args += 6;
+ break;
+ case INDEX_op_setcond2_i32:
+ /* Simplify LT/GE comparisons vs zero to a single compare
+ vs the high word of the input. */
+ if ((args[5] == TCG_COND_LT || args[5] == TCG_COND_GE)
+ && temps[args[3]].state == TCG_TEMP_CONST
+ && temps[args[4]].state == TCG_TEMP_CONST
+ && temps[args[3]].val == 0
+ && temps[args[4]].val == 0) {
+ gen_opc_buf[op_index] = INDEX_op_setcond_i32;
+ args[1] = args[2];
+ args[2] = args[4];
+ args[3] = args[5];
+ gen_args += 4;
+ } else {
+ reset_temp(args[0]);
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args[3] = args[3];
+ gen_args[4] = args[4];
+ gen_args[5] = args[5];
+ gen_args += 6;
+ }
+ args += 6;
+ break;
case INDEX_op_call:
nb_call_args = (args[0] >> 16) + (args[0] & 0xffff);
if (!(args[nb_call_args + 1] & (TCG_CALL_CONST | TCG_CALL_PURE))) {
--
1.7.11.4
- [Qemu-devel] [PATCH 0/7] Double-word tcg/optimize improvements, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 1/7] tcg: Split out swap_commutative as a subroutine, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 2/7] tcg: Optimize add2 + sub2, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 4/7] tcg: Optimize double-word comparisons against zero,
Richard Henderson <=
- [Qemu-devel] [PATCH 7/7] tcg: Do constant folding on double-word comparisons, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 6/7] tcg: Tidy brcond optimization, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 3/7] tcg: Swap commutative double-word comparisons, Richard Henderson, 2012/09/27
- [Qemu-devel] [PATCH 5/7] tcg: Split out subroutines from do_constant_folding_cond, Richard Henderson, 2012/09/27