Optimize PowerPC overflow flag computation in most useful cases.
Use the same routines to check overflow for addo, subfo and PowerPC 405
multiply and add cases.
Fix carry reset in addme(o) and subfme(o) cases.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3574 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/target-ppc/op.c b/target-ppc/op.c
index 730dc0e..bbc5c5b 100644
--- a/target-ppc/op.c
+++ b/target-ppc/op.c
@@ -191,6 +191,12 @@
RETURN();
}
+void OPPROTO op_moven_T2_T0 (void)
+{
+ T2 = ~T0;
+ RETURN();
+}
+
/* Generate exceptions */
void OPPROTO op_raise_exception_err (void)
{
@@ -847,26 +853,18 @@
void OPPROTO op_check_addo (void)
{
- if (likely(!(((uint32_t)T2 ^ (uint32_t)T1 ^ UINT32_MAX) &
- ((uint32_t)T2 ^ (uint32_t)T0) & (1UL << 31)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = (((uint32_t)T2 ^ (uint32_t)T1 ^ UINT32_MAX) &
+ ((uint32_t)T2 ^ (uint32_t)T0)) >> 31;
+ xer_so |= xer_ov;
RETURN();
}
#if defined(TARGET_PPC64)
void OPPROTO op_check_addo_64 (void)
{
- if (likely(!(((uint64_t)T2 ^ (uint64_t)T1 ^ UINT64_MAX) &
- ((uint64_t)T2 ^ (uint64_t)T0) & (1ULL << 63)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = (((uint64_t)T2 ^ (uint64_t)T1 ^ UINT64_MAX) &
+ ((uint64_t)T2 ^ (uint64_t)T0)) >> 63;
+ xer_so |= xer_ov;
RETURN();
}
#endif
@@ -922,6 +920,8 @@
T0 += xer_ca + (-1);
if (likely((uint32_t)T1 != 0))
xer_ca = 1;
+ else
+ xer_ca = 0;
RETURN();
}
@@ -931,6 +931,8 @@
T0 += xer_ca + (-1);
if (likely((uint64_t)T1 != 0))
xer_ca = 1;
+ else
+ xer_ca = 0;
RETURN();
}
#endif
@@ -1142,32 +1144,6 @@
RETURN();
}
-void OPPROTO op_check_subfo (void)
-{
- if (likely(!(((uint32_t)(~T2) ^ (uint32_t)T1 ^ UINT32_MAX) &
- ((uint32_t)(~T2) ^ (uint32_t)T0) & (1UL << 31)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
- RETURN();
-}
-
-#if defined(TARGET_PPC64)
-void OPPROTO op_check_subfo_64 (void)
-{
- if (likely(!(((uint64_t)(~T2) ^ (uint64_t)T1 ^ UINT64_MAX) &
- ((uint64_t)(~T2) ^ (uint64_t)T0) & (1ULL << 63)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
- RETURN();
-}
-#endif
-
/* subtract from carrying */
void OPPROTO op_check_subfc (void)
{
@@ -1235,8 +1211,10 @@
void OPPROTO op_subfme (void)
{
T0 = ~T0 + xer_ca - 1;
- if (likely((uint32_t)T0 != (uint32_t)-1))
+ if (likely((uint32_t)T0 != UINT32_MAX))
xer_ca = 1;
+ else
+ xer_ca = 0;
RETURN();
}
@@ -1244,8 +1222,10 @@
void OPPROTO op_subfme_64 (void)
{
T0 = ~T0 + xer_ca - 1;
- if (likely((uint64_t)T0 != (uint64_t)-1))
+ if (likely((uint64_t)T0 != UINT64_MAX))
xer_ca = 1;
+ else
+ xer_ca = 0;
RETURN();
}
#endif
@@ -2528,12 +2508,6 @@
RETURN();
}
-void OPPROTO op_405_check_ov (void)
-{
- do_405_check_ov();
- RETURN();
-}
-
void OPPROTO op_405_check_sat (void)
{
do_405_check_sat();
diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
index 6ed9c95..75bf33b 100644
--- a/target-ppc/op_helper.c
+++ b/target-ppc/op_helper.c
@@ -151,15 +151,12 @@
{
T1 = T0;
T0 += xer_ca + (-1);
- if (likely(!((uint32_t)T1 &
- ((uint32_t)T1 ^ (uint32_t)T0) & (1UL << 31)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = ((uint32_t)T1 & ((uint32_t)T1 ^ (uint32_t)T0)) >> 31;
+ xer_so |= xer_ov;
if (likely(T1 != 0))
xer_ca = 1;
+ else
+ xer_ca = 0;
}
#if defined(TARGET_PPC64)
@@ -167,15 +164,12 @@
{
T1 = T0;
T0 += xer_ca + (-1);
- if (likely(!((uint64_t)T1 &
- ((uint64_t)T1 ^ (uint64_t)T0) & (1ULL << 63)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = ((uint64_t)T1 & ((uint64_t)T1 ^ (uint64_t)T0)) >> 63;
+ xer_so |= xer_ov;
if (likely(T1 != 0))
xer_ca = 1;
+ else
+ xer_ca = 0;
}
#endif
@@ -316,15 +310,12 @@
{
T1 = T0;
T0 = ~T0 + xer_ca - 1;
- if (likely(!((uint32_t)~T1 & ((uint32_t)~T1 ^ (uint32_t)T0) &
- (1UL << 31)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = ((uint32_t)~T1 & ((uint32_t)~T1 ^ (uint32_t)T0)) >> 31;
+ xer_so |= xer_ov;
if (likely((uint32_t)T1 != UINT32_MAX))
xer_ca = 1;
+ else
+ xer_ca = 0;
}
#if defined(TARGET_PPC64)
@@ -332,15 +323,12 @@
{
T1 = T0;
T0 = ~T0 + xer_ca - 1;
- if (likely(!((uint64_t)~T1 & ((uint64_t)~T1 ^ (uint64_t)T0) &
- (1ULL << 63)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = ((uint64_t)~T1 & ((uint64_t)~T1 ^ (uint64_t)T0)) >> 63;
+ xer_so |= xer_ov;
if (likely((uint64_t)T1 != UINT64_MAX))
xer_ca = 1;
+ else
+ xer_ca = 0;
}
#endif
@@ -348,13 +336,9 @@
{
T1 = T0;
T0 = ~T0 + xer_ca;
- if (likely(!(((uint32_t)~T1 ^ UINT32_MAX) &
- ((uint32_t)(~T1) ^ (uint32_t)T0) & (1UL << 31)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = (((uint32_t)~T1 ^ UINT32_MAX) &
+ ((uint32_t)(~T1) ^ (uint32_t)T0)) >> 31;
+ xer_so |= xer_ov;
if (likely((uint32_t)T0 >= (uint32_t)~T1)) {
xer_ca = 0;
} else {
@@ -367,13 +351,9 @@
{
T1 = T0;
T0 = ~T0 + xer_ca;
- if (likely(!(((uint64_t)~T1 ^ UINT64_MAX) &
- ((uint64_t)(~T1) ^ (uint64_t)T0) & (1ULL << 63)))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
+ xer_ov = (((uint64_t)~T1 ^ UINT64_MAX) &
+ ((uint64_t)(~T1) ^ (uint64_t)T0)) >> 63;
+ xer_so |= xer_ov;
if (likely((uint64_t)T0 >= (uint64_t)~T1)) {
xer_ca = 0;
} else {
@@ -1755,17 +1735,6 @@
/*****************************************************************************/
/* Embedded PowerPC specific helpers */
-void do_405_check_ov (void)
-{
- if (likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
- !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
- xer_ov = 0;
- } else {
- xer_ov = 1;
- xer_so = 1;
- }
-}
-
void do_405_check_sat (void)
{
if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
diff --git a/target-ppc/op_helper.h b/target-ppc/op_helper.h
index 6575d3d..5b77cb2 100644
--- a/target-ppc/op_helper.h
+++ b/target-ppc/op_helper.h
@@ -182,7 +182,6 @@
#endif
/* PowerPC 4xx specific helpers */
-void do_405_check_ov (void);
void do_405_check_sat (void);
void do_load_dcr (void);
void do_store_dcr (void);
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index 1adff9f..73b2e22 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -888,17 +888,17 @@
/* subf subf. subfo subfo. */
static always_inline void gen_op_subfo (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subf();
- gen_op_check_subfo();
+ gen_op_check_addo();
}
#if defined(TARGET_PPC64)
#define gen_op_subf_64 gen_op_subf
static always_inline void gen_op_subfo_64 (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subf();
- gen_op_check_subfo_64();
+ gen_op_check_addo_64();
}
#endif
GEN_INT_ARITH2_64 (subf, 0x1F, 0x08, 0x01, PPC_INTEGER);
@@ -910,10 +910,10 @@
}
static always_inline void gen_op_subfco (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subf();
gen_op_check_subfc();
- gen_op_check_subfo();
+ gen_op_check_addo();
}
#if defined(TARGET_PPC64)
static always_inline void gen_op_subfc_64 (void)
@@ -923,27 +923,27 @@
}
static always_inline void gen_op_subfco_64 (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subf();
gen_op_check_subfc_64();
- gen_op_check_subfo_64();
+ gen_op_check_addo_64();
}
#endif
GEN_INT_ARITH2_64 (subfc, 0x1F, 0x08, 0x00, PPC_INTEGER);
/* subfe subfe. subfeo subfeo. */
static always_inline void gen_op_subfeo (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subfe();
- gen_op_check_subfo();
+ gen_op_check_addo();
}
#if defined(TARGET_PPC64)
#define gen_op_subfe_64 gen_op_subfe
static always_inline void gen_op_subfeo_64 (void)
{
- gen_op_move_T2_T0();
+ gen_op_moven_T2_T0();
gen_op_subfe_64();
- gen_op_check_subfo_64();
+ gen_op_check_addo_64();
}
#endif
GEN_INT_ARITH2_64 (subfe, 0x1F, 0x08, 0x04, PPC_INTEGER);
@@ -5116,7 +5116,7 @@
if (opc3 & 0x10) {
/* Check overflow */
if (opc3 & 0x01)
- gen_op_405_check_ov();
+ gen_op_check_addo();
else
gen_op_405_check_ovu();
}
