From: LemonBoy <thatlemon@gmail.com>
To: qemu-devel@nongnu.org
Cc: LemonBoy <thatlemon@gmail.com>,
richard.henderson@linaro.org, qemu-ppc@nongnu.org,
david@gibson.dropbear.id.au
Subject: [PATCH v3 3/4] ppc/translate: Delay NaN checking after comparison
Date: Fri, 13 Nov 2020 00:01:29 +0100 [thread overview]
Message-ID: <20201112230130.65262-4-thatlemon@gmail.com> (raw)
In-Reply-To: <20201112230130.65262-1-thatlemon@gmail.com>
Since we always perform a comparison between the two operands avoid
checking for NaN unless the result states they're unordered.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
target/ppc/fpu_helper.c | 80 +++++++++++++++++++++--------------------
1 file changed, 42 insertions(+), 38 deletions(-)
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
index 6600520221..08fcaed723 100644
--- a/target/ppc/fpu_helper.c
+++ b/target/ppc/fpu_helper.c
@@ -2475,25 +2475,6 @@ static inline void do_scalar_cmp(CPUPPCState *env, ppc_vsr_t *xa, ppc_vsr_t *xb,
helper_reset_fpstatus(env);
- if (float64_is_signaling_nan(xa->VsrD(0), &env->fp_status) ||
- float64_is_signaling_nan(xb->VsrD(0), &env->fp_status)) {
- vxsnan_flag = true;
- if (fpscr_ve == 0 && ordered) {
- vxvc_flag = true;
- }
- } else if (float64_is_quiet_nan(xa->VsrD(0), &env->fp_status) ||
- float64_is_quiet_nan(xb->VsrD(0), &env->fp_status)) {
- if (ordered) {
- vxvc_flag = true;
- }
- }
- if (vxsnan_flag) {
- float_invalid_op_vxsnan(env, GETPC());
- }
- if (vxvc_flag) {
- float_invalid_op_vxvc(env, 0, GETPC());
- }
-
switch (float64_compare(xa->VsrD(0), xb->VsrD(0), &env->fp_status)) {
case float_relation_less:
cc = CRF_LT;
@@ -2506,6 +2487,27 @@ static inline void do_scalar_cmp(CPUPPCState *env, ppc_vsr_t *xa, ppc_vsr_t *xb,
break;
case float_relation_unordered:
cc = CRF_SO;
+
+ if (float64_is_signaling_nan(xa->VsrD(0), &env->fp_status) ||
+ float64_is_signaling_nan(xb->VsrD(0), &env->fp_status)) {
+ vxsnan_flag = true;
+ if (fpscr_ve == 0 && ordered) {
+ vxvc_flag = true;
+ }
+ } else if (float64_is_quiet_nan(xa->VsrD(0), &env->fp_status) ||
+ float64_is_quiet_nan(xb->VsrD(0), &env->fp_status)) {
+ if (ordered) {
+ vxvc_flag = true;
+ }
+ }
+
+ if (vxsnan_flag) {
+ float_invalid_op_vxsnan(env, GETPC());
+ }
+ if (vxvc_flag) {
+ float_invalid_op_vxvc(env, 0, GETPC());
+ }
+
break;
default:
g_assert_not_reached();
@@ -2538,25 +2540,6 @@ static inline void do_scalar_cmpq(CPUPPCState *env, ppc_vsr_t *xa,
helper_reset_fpstatus(env);
- if (float128_is_signaling_nan(xa->f128, &env->fp_status) ||
- float128_is_signaling_nan(xb->f128, &env->fp_status)) {
- vxsnan_flag = true;
- if (fpscr_ve == 0 && ordered) {
- vxvc_flag = true;
- }
- } else if (float128_is_quiet_nan(xa->f128, &env->fp_status) ||
- float128_is_quiet_nan(xb->f128, &env->fp_status)) {
- if (ordered) {
- vxvc_flag = true;
- }
- }
- if (vxsnan_flag) {
- float_invalid_op_vxsnan(env, GETPC());
- }
- if (vxvc_flag) {
- float_invalid_op_vxvc(env, 0, GETPC());
- }
-
switch (float128_compare(xa->f128, xb->f128, &env->fp_status)) {
case float_relation_less:
cc = CRF_LT;
@@ -2569,6 +2552,27 @@ static inline void do_scalar_cmpq(CPUPPCState *env, ppc_vsr_t *xa,
break;
case float_relation_unordered:
cc = CRF_SO;
+
+ if (float128_is_signaling_nan(xa->f128, &env->fp_status) ||
+ float128_is_signaling_nan(xb->f128, &env->fp_status)) {
+ vxsnan_flag = true;
+ if (fpscr_ve == 0 && ordered) {
+ vxvc_flag = true;
+ }
+ } else if (float128_is_quiet_nan(xa->f128, &env->fp_status) ||
+ float128_is_quiet_nan(xb->f128, &env->fp_status)) {
+ if (ordered) {
+ vxvc_flag = true;
+ }
+ }
+
+ if (vxsnan_flag) {
+ float_invalid_op_vxsnan(env, GETPC());
+ }
+ if (vxvc_flag) {
+ float_invalid_op_vxvc(env, 0, GETPC());
+ }
+
break;
default:
g_assert_not_reached();
--
2.27.0
next prev parent reply other threads:[~2020-11-12 23:05 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-12 23:01 [PATCH v3 0/4] ppc/translate: Fix unordered f64/f128 comparisons LemonBoy
2020-11-12 23:01 ` [PATCH v3 1/4] " LemonBoy
2020-11-12 23:01 ` [PATCH v3 2/4] ppc/translate: Turn the helper macros into functions LemonBoy
2020-11-12 23:01 ` LemonBoy [this message]
2020-11-12 23:01 ` [PATCH v3 4/4] ppc/translate: Raise exceptions after setting the cc LemonBoy
2020-11-23 6:08 ` [PATCH v3 0/4] ppc/translate: Fix unordered f64/f128 comparisons David Gibson
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