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[PATCH] Hexagon: fix F2_conv_* instructions for negative zero

Matheus Tavares Bernardino posted 1 patch 1 year, 6 months ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/9f3be6911db2dcff834ce6b530118fa383b9e46a.1722186937.git.quic._5Fmathbern@quicinc.com
Maintainers: Brian Cain <brian.cain@oss.qualcomm.com>
There is a newer version of this series
target/hexagon/op_helper.c | 16 ++++++++--------
tests/tcg/hexagon/usr.c    | 10 ++++++++++
2 files changed, 18 insertions(+), 8 deletions(-)
[PATCH] Hexagon: fix F2_conv_* instructions for negative zero
Posted by Matheus Tavares Bernardino 1 year, 6 months ago 
The implementation for these instructions handles -0 as an invalid float
point value, whereas the Hexagon hardware considers it the same as +0
(which is valid). Let's fix that and add a regression test.

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
---
 target/hexagon/op_helper.c | 16 ++++++++--------
 tests/tcg/hexagon/usr.c    | 10 ++++++++++
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
index ae5a605513..e1fc88aa0d 100644
--- a/target/hexagon/op_helper.c
+++ b/target/hexagon/op_helper.c
@@ -683,7 +683,7 @@ uint32_t HELPER(conv_sf2uw)(CPUHexagonState *env, float32 RsV)
     uint32_t RdV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
+    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RdV = 0;
     } else {
@@ -713,7 +713,7 @@ uint64_t HELPER(conv_sf2ud)(CPUHexagonState *env, float32 RsV)
     uint64_t RddV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
+    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RddV = 0;
     } else {
@@ -743,7 +743,7 @@ uint32_t HELPER(conv_df2uw)(CPUHexagonState *env, float64 RssV)
     uint32_t RdV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
+    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RdV = 0;
     } else {
@@ -773,7 +773,7 @@ uint64_t HELPER(conv_df2ud)(CPUHexagonState *env, float64 RssV)
     uint64_t RddV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
+    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RddV = 0;
     } else {
@@ -803,7 +803,7 @@ uint32_t HELPER(conv_sf2uw_chop)(CPUHexagonState *env, float32 RsV)
     uint32_t RdV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
+    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RdV = 0;
     } else {
@@ -833,7 +833,7 @@ uint64_t HELPER(conv_sf2ud_chop)(CPUHexagonState *env, float32 RsV)
     uint64_t RddV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
+    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RddV = 0;
     } else {
@@ -863,7 +863,7 @@ uint32_t HELPER(conv_df2uw_chop)(CPUHexagonState *env, float64 RssV)
     uint32_t RdV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
+    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RdV = 0;
     } else {
@@ -893,7 +893,7 @@ uint64_t HELPER(conv_df2ud_chop)(CPUHexagonState *env, float64 RssV)
     uint64_t RddV;
     arch_fpop_start(env);
     /* Hexagon checks the sign before rounding */
-    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
+    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
         float_raise(float_flag_invalid, &env->fp_status);
         RddV = 0;
     } else {
diff --git a/tests/tcg/hexagon/usr.c b/tests/tcg/hexagon/usr.c
index 92bc86a213..95d04762bf 100644
--- a/tests/tcg/hexagon/usr.c
+++ b/tests/tcg/hexagon/usr.c
@@ -1007,6 +1007,11 @@ int main()
     TEST_P_OP_R(conv_sf2d_chop,   SF_QNaN,  0xffffffffffffffffULL,  USR_FPINVF);
     TEST_P_OP_R(conv_sf2d_chop,   SF_SNaN,  0xffffffffffffffffULL,  USR_FPINVF);
 
+    TEST_R_OP_R(conv_sf2uw,       SF_zero_neg,  0, USR_CLEAR);
+    TEST_R_OP_R(conv_sf2uw_chop,  SF_zero_neg,  0, USR_CLEAR);
+    TEST_P_OP_R(conv_sf2ud,       SF_zero_neg,  0, USR_CLEAR);
+    TEST_P_OP_R(conv_sf2ud_chop,  SF_zero_neg,  0, USR_CLEAR);
+
     TEST_R_OP_P(conv_df2sf,       DF_QNaN,  SF_HEX_NaN,             USR_CLEAR);
     TEST_R_OP_P(conv_df2sf,       DF_SNaN,  SF_HEX_NaN,             USR_FPINVF);
     TEST_R_OP_P(conv_df2uw,       DF_QNaN,  0xffffffff,             USR_FPINVF);
@@ -1020,6 +1025,11 @@ int main()
     TEST_R_OP_P(conv_df2uw_chop,  DF_QNaN,  0xffffffff,             USR_FPINVF);
     TEST_R_OP_P(conv_df2uw_chop,  DF_SNaN,  0xffffffff,             USR_FPINVF);
 
+    TEST_R_OP_P(conv_df2uw,       DF_zero_neg,  0, USR_CLEAR);
+    TEST_R_OP_P(conv_df2uw_chop,  DF_zero_neg,  0, USR_CLEAR);
+    TEST_P_OP_P(conv_df2ud,       DF_zero_neg,  0, USR_CLEAR);
+    TEST_P_OP_P(conv_df2ud_chop,  DF_zero_neg,  0, USR_CLEAR);
+
     /* Test for typo in HELPER(conv_df2uw_chop) */
     TEST_R_OP_P(conv_df2uw_chop, 0xffffff7f00000001ULL, 0xffffffff, USR_FPINVF);
 
-- 
2.37.2
RE: [PATCH] Hexagon: fix F2_conv_* instructions for negative zero
Posted by ltaylorsimpson@gmail.com 1 year, 6 months ago 

> -----Original Message-----
> From: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
> Sent: Sunday, July 28, 2024 11:16 AM
> To: qemu-devel@nongnu.org
> Cc: ltaylorsimpson@gmail.com; bcain@quicinc.com; sidneym@quicinc.com;
> ale@rev.ng; anjo@rev.ng
> Subject: [PATCH] Hexagon: fix F2_conv_* instructions for negative zero
> 
> The implementation for these instructions handles -0 as an invalid float
point
> value, whereas the Hexagon hardware considers it the same as +0 (which is
> valid). Let's fix that and add a regression test.
> 
> Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
> ---
>  target/hexagon/op_helper.c | 16 ++++++++--------
>  tests/tcg/hexagon/usr.c    | 10 ++++++++++
>  2 files changed, 18 insertions(+), 8 deletions(-)


You should update the copyright year to 2024 in the files you changed.

Otherwise
Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Re: [PATCH] Hexagon: fix F2_conv_* instructions for negative zero
Posted by Brian Cain 1 year, 6 months ago 
On 7/28/2024 12:15 PM, Matheus Tavares Bernardino wrote:
> The implementation for these instructions handles -0 as an invalid float
> point value, whereas the Hexagon hardware considers it the same as +0
> (which is valid). Let's fix that and add a regression test.
>
> Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
> ---

Reviewed-by: Brian Cain <bcain@quicinc.com>


>   target/hexagon/op_helper.c | 16 ++++++++--------
>   tests/tcg/hexagon/usr.c    | 10 ++++++++++
>   2 files changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
> index ae5a605513..e1fc88aa0d 100644
> --- a/target/hexagon/op_helper.c
> +++ b/target/hexagon/op_helper.c
> @@ -683,7 +683,7 @@ uint32_t HELPER(conv_sf2uw)(CPUHexagonState *env, float32 RsV)
>       uint32_t RdV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
> +    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RdV = 0;
>       } else {
> @@ -713,7 +713,7 @@ uint64_t HELPER(conv_sf2ud)(CPUHexagonState *env, float32 RsV)
>       uint64_t RddV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
> +    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RddV = 0;
>       } else {
> @@ -743,7 +743,7 @@ uint32_t HELPER(conv_df2uw)(CPUHexagonState *env, float64 RssV)
>       uint32_t RdV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
> +    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RdV = 0;
>       } else {
> @@ -773,7 +773,7 @@ uint64_t HELPER(conv_df2ud)(CPUHexagonState *env, float64 RssV)
>       uint64_t RddV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
> +    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RddV = 0;
>       } else {
> @@ -803,7 +803,7 @@ uint32_t HELPER(conv_sf2uw_chop)(CPUHexagonState *env, float32 RsV)
>       uint32_t RdV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
> +    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RdV = 0;
>       } else {
> @@ -833,7 +833,7 @@ uint64_t HELPER(conv_sf2ud_chop)(CPUHexagonState *env, float32 RsV)
>       uint64_t RddV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV)) {
> +    if (float32_is_neg(RsV) && !float32_is_any_nan(RsV) && !float32_is_zero(RsV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RddV = 0;
>       } else {
> @@ -863,7 +863,7 @@ uint32_t HELPER(conv_df2uw_chop)(CPUHexagonState *env, float64 RssV)
>       uint32_t RdV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
> +    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RdV = 0;
>       } else {
> @@ -893,7 +893,7 @@ uint64_t HELPER(conv_df2ud_chop)(CPUHexagonState *env, float64 RssV)
>       uint64_t RddV;
>       arch_fpop_start(env);
>       /* Hexagon checks the sign before rounding */
> -    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV)) {
> +    if (float64_is_neg(RssV) && !float64_is_any_nan(RssV) && !float64_is_zero(RssV)) {
>           float_raise(float_flag_invalid, &env->fp_status);
>           RddV = 0;
>       } else {
> diff --git a/tests/tcg/hexagon/usr.c b/tests/tcg/hexagon/usr.c
> index 92bc86a213..95d04762bf 100644
> --- a/tests/tcg/hexagon/usr.c
> +++ b/tests/tcg/hexagon/usr.c
> @@ -1007,6 +1007,11 @@ int main()
>       TEST_P_OP_R(conv_sf2d_chop,   SF_QNaN,  0xffffffffffffffffULL,  USR_FPINVF);
>       TEST_P_OP_R(conv_sf2d_chop,   SF_SNaN,  0xffffffffffffffffULL,  USR_FPINVF);
>   
> +    TEST_R_OP_R(conv_sf2uw,       SF_zero_neg,  0, USR_CLEAR);
> +    TEST_R_OP_R(conv_sf2uw_chop,  SF_zero_neg,  0, USR_CLEAR);
> +    TEST_P_OP_R(conv_sf2ud,       SF_zero_neg,  0, USR_CLEAR);
> +    TEST_P_OP_R(conv_sf2ud_chop,  SF_zero_neg,  0, USR_CLEAR);
> +
>       TEST_R_OP_P(conv_df2sf,       DF_QNaN,  SF_HEX_NaN,             USR_CLEAR);
>       TEST_R_OP_P(conv_df2sf,       DF_SNaN,  SF_HEX_NaN,             USR_FPINVF);
>       TEST_R_OP_P(conv_df2uw,       DF_QNaN,  0xffffffff,             USR_FPINVF);
> @@ -1020,6 +1025,11 @@ int main()
>       TEST_R_OP_P(conv_df2uw_chop,  DF_QNaN,  0xffffffff,             USR_FPINVF);
>       TEST_R_OP_P(conv_df2uw_chop,  DF_SNaN,  0xffffffff,             USR_FPINVF);
>   
> +    TEST_R_OP_P(conv_df2uw,       DF_zero_neg,  0, USR_CLEAR);
> +    TEST_R_OP_P(conv_df2uw_chop,  DF_zero_neg,  0, USR_CLEAR);
> +    TEST_P_OP_P(conv_df2ud,       DF_zero_neg,  0, USR_CLEAR);
> +    TEST_P_OP_P(conv_df2ud_chop,  DF_zero_neg,  0, USR_CLEAR);
> +
>       /* Test for typo in HELPER(conv_df2uw_chop) */
>       TEST_R_OP_P(conv_df2uw_chop, 0xffffff7f00000001ULL, 0xffffffff, USR_FPINVF);
>

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