qemu/0063-tcg-mips-optimize-brcond-arg-0.patch
2012-10-28 14:05:07 -04:00

100 lines
3.7 KiB
Diff

From e30cf829e9d8200364b53b9189c76d2155a32876 Mon Sep 17 00:00:00 2001
From: Aurelien Jarno <aurelien@aurel32.net>
Date: Fri, 21 Sep 2012 18:20:26 +0200
Subject: [PATCH] tcg/mips: optimize brcond arg, 0
MIPS has some conditional branch instructions when comparing with zero.
Use them.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
tcg/mips/tcg-target.c | 38 ++++++++++++++++++++++++++++++--------
1 file changed, 30 insertions(+), 8 deletions(-)
diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c
index c05169f..6aa4527 100644
--- a/tcg/mips/tcg-target.c
+++ b/tcg/mips/tcg-target.c
@@ -278,6 +278,8 @@ static inline int tcg_target_const_match(tcg_target_long val,
enum {
OPC_BEQ = 0x04 << 26,
OPC_BNE = 0x05 << 26,
+ OPC_BLEZ = 0x06 << 26,
+ OPC_BGTZ = 0x07 << 26,
OPC_ADDIU = 0x09 << 26,
OPC_SLTI = 0x0A << 26,
OPC_SLTIU = 0x0B << 26,
@@ -319,6 +321,10 @@ enum {
OPC_SLT = OPC_SPECIAL | 0x2A,
OPC_SLTU = OPC_SPECIAL | 0x2B,
+ OPC_REGIMM = 0x01 << 26,
+ OPC_BLTZ = OPC_REGIMM | (0x00 << 16),
+ OPC_BGEZ = OPC_REGIMM | (0x01 << 16),
+
OPC_SPECIAL3 = 0x1f << 26,
OPC_SEB = OPC_SPECIAL3 | 0x420,
OPC_SEH = OPC_SPECIAL3 | 0x620,
@@ -590,32 +596,48 @@ static void tcg_out_brcond(TCGContext *s, TCGCond cond, TCGArg arg1,
tcg_out_opc_br(s, OPC_BNE, arg1, arg2);
break;
case TCG_COND_LT:
- tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg1, arg2);
- tcg_out_opc_br(s, OPC_BNE, TCG_REG_AT, TCG_REG_ZERO);
+ if (arg2 == 0) {
+ tcg_out_opc_br(s, OPC_BLTZ, 0, arg1);
+ } else {
+ tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg1, arg2);
+ tcg_out_opc_br(s, OPC_BNE, TCG_REG_AT, TCG_REG_ZERO);
+ }
break;
case TCG_COND_LTU:
tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_AT, arg1, arg2);
tcg_out_opc_br(s, OPC_BNE, TCG_REG_AT, TCG_REG_ZERO);
break;
case TCG_COND_GE:
- tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg1, arg2);
- tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
+ if (arg2 == 0) {
+ tcg_out_opc_br(s, OPC_BGEZ, 0, arg1);
+ } else {
+ tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg1, arg2);
+ tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
+ }
break;
case TCG_COND_GEU:
tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_AT, arg1, arg2);
tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
break;
case TCG_COND_LE:
- tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg2, arg1);
- tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
+ if (arg2 == 0) {
+ tcg_out_opc_br(s, OPC_BLEZ, 0, arg1);
+ } else {
+ tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg2, arg1);
+ tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
+ }
break;
case TCG_COND_LEU:
tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_AT, arg2, arg1);
tcg_out_opc_br(s, OPC_BEQ, TCG_REG_AT, TCG_REG_ZERO);
break;
case TCG_COND_GT:
- tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg2, arg1);
- tcg_out_opc_br(s, OPC_BNE, TCG_REG_AT, TCG_REG_ZERO);
+ if (arg2 == 0) {
+ tcg_out_opc_br(s, OPC_BGTZ, 0, arg1);
+ } else {
+ tcg_out_opc_reg(s, OPC_SLT, TCG_REG_AT, arg2, arg1);
+ tcg_out_opc_br(s, OPC_BNE, TCG_REG_AT, TCG_REG_ZERO);
+ }
break;
case TCG_COND_GTU:
tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_AT, arg2, arg1);
--
1.7.12.1