Removed Soft float from MIPS

Message ID 20200812213535.25430-1-eshandhawan51@gmail.com
State New
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Series
  • Removed Soft float from MIPS
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Commit Message

Eshan dhawan via Newlib Aug. 12, 2020, 9:35 p.m.
This Patch removes Soft Float code from MIPS.
Instead It adds the soft float code from RISCV

Signed-off-by: Eshan dhawan <eshandhawan51@gmail.com>

---
 .../machine/mips/machine/fenv-softfloat.h     | 55 +++++++------------
 newlib/libm/machine/mips/fenv.c               | 10 ----
 2 files changed, 21 insertions(+), 44 deletions(-)

-- 
2.17.1

Comments

Eshan dhawan via Newlib Aug. 13, 2020, 8:19 a.m. | #1
On Aug 13 03:05, Eshan dhawan via Newlib wrote:
> This Patch removes Soft Float code from MIPS.

> Instead It adds the soft float code from RISCV


Why, and why is that the right thing to do?


Thanks,
Corinna

> Signed-off-by: Eshan dhawan <eshandhawan51@gmail.com>

> ---

>  .../machine/mips/machine/fenv-softfloat.h     | 55 +++++++------------

>  newlib/libm/machine/mips/fenv.c               | 10 ----

>  2 files changed, 21 insertions(+), 44 deletions(-)
Joel Sherrill Aug. 13, 2020, 1:10 p.m. | #2
On Thu, Aug 13, 2020 at 3:19 AM Corinna Vinschen via Newlib <
newlib@sourceware.org> wrote:

> On Aug 13 03:05, Eshan dhawan via Newlib wrote:

> > This Patch removes Soft Float code from MIPS.

> > Instead It adds the soft float code from RISCV

>

> Why, and why is that the right thing to do?

>


The code came from FreeBSD and assumes the FreeBSD softfp
implementation not the one with GCC. That was an overlooked and
fixed in the other fenv code already.

--joel

>

>

> Thanks,

> Corinna

>

> > Signed-off-by: Eshan dhawan <eshandhawan51@gmail.com>

> > ---

> >  .../machine/mips/machine/fenv-softfloat.h     | 55 +++++++------------

> >  newlib/libm/machine/mips/fenv.c               | 10 ----

> >  2 files changed, 21 insertions(+), 44 deletions(-)

>

>
Sebastian Huber Aug. 14, 2020, 4:51 a.m. | #3
On 13/08/2020 15:10, Joel Sherrill wrote:

> On Thu, Aug 13, 2020 at 3:19 AM Corinna Vinschen via Newlib <

> newlib@sourceware.org> wrote:

>

>> On Aug 13 03:05, Eshan dhawan via Newlib wrote:

>>> This Patch removes Soft Float code from MIPS.

>>> Instead It adds the soft float code from RISCV

>> Why, and why is that the right thing to do?

>>

> The code came from FreeBSD and assumes the FreeBSD softfp

> implementation not the one with GCC. That was an overlooked and

> fixed in the other fenv code already.

There is now a lot of copy and paste involved in the fenv support. I 
think the soft float support should be unified with a shared 
implementation. This can be later enhanced with support for the GCC soft 
float implementation.
Eshan dhawan via Newlib Aug. 17, 2020, 9:22 a.m. | #4
On Aug 13 08:10, Joel Sherrill wrote:
> On Thu, Aug 13, 2020 at 3:19 AM Corinna Vinschen via Newlib <

> newlib@sourceware.org> wrote:

> 

> > On Aug 13 03:05, Eshan dhawan via Newlib wrote:

> > > This Patch removes Soft Float code from MIPS.

> > > Instead It adds the soft float code from RISCV

> >

> > Why, and why is that the right thing to do?

> >

> 

> The code came from FreeBSD and assumes the FreeBSD softfp

> implementation not the one with GCC. That was an overlooked and

> fixed in the other fenv code already.

> 

> --joel


That information belongs into the commit message.


Corinna
Eshan dhawan via Newlib Aug. 17, 2020, 9:23 a.m. | #5
On Aug 14 06:51, Sebastian Huber wrote:
> On 13/08/2020 15:10, Joel Sherrill wrote:

> 

> > On Thu, Aug 13, 2020 at 3:19 AM Corinna Vinschen via Newlib <

> > newlib@sourceware.org> wrote:

> > 

> > > On Aug 13 03:05, Eshan dhawan via Newlib wrote:

> > > > This Patch removes Soft Float code from MIPS.

> > > > Instead It adds the soft float code from RISCV

> > > Why, and why is that the right thing to do?

> > > 

> > The code came from FreeBSD and assumes the FreeBSD softfp

> > implementation not the one with GCC. That was an overlooked and

> > fixed in the other fenv code already.

> There is now a lot of copy and paste involved in the fenv support. I think

> the soft float support should be unified with a shared implementation. This

> can be later enhanced with support for the GCC soft float implementation.


Sounds like a good idea to me.


Corinna

Patch

diff --git a/newlib/libc/machine/mips/machine/fenv-softfloat.h b/newlib/libc/machine/mips/machine/fenv-softfloat.h
index cf13e73fc..7c8bc3a89 100644
--- a/newlib/libc/machine/mips/machine/fenv-softfloat.h
+++ b/newlib/libc/machine/mips/machine/fenv-softfloat.h
@@ -50,16 +50,11 @@ 
  * doesn't matter how you define them.
  */
 #include <errno.h>
-int __softfloat_float_exception_flags;
-int __softfloat_float_exception_mask;
-int __softfloat_float_rounding_mode;
-
 
 __fenv_static inline int
 feclearexcept(int excepts)
 {
 
-	__softfloat_float_exception_flags &= ~excepts;
 	return (0);
 }
 
@@ -67,16 +62,14 @@  __fenv_static inline int
 fegetexceptflag(fexcept_t *flagp, int excepts)
 {
 
-	*flagp = __softfloat_float_exception_flags & excepts;
 	return (0);
+
 }
 
 __fenv_static inline int
 fesetexceptflag(const fexcept_t *flagp, int excepts)
 {
 
-	__softfloat_float_exception_flags &= ~excepts;
-	__softfloat_float_exception_flags |= *flagp & excepts;
 	return (0);
 }
 
@@ -84,7 +77,7 @@  __fenv_static inline int
 feraiseexcept(int excepts)
 {
 
-return(excepts  ?  -ENOTSUP : 0 );
+	return( excepts != 0 );
 
 }
 
@@ -92,21 +85,25 @@  __fenv_static inline int
 fetestexcept(int excepts)
 {
 
-	return (__softfloat_float_exception_flags & excepts);
+	return (0);
 }
 
 __fenv_static inline int
 fegetround(void)
 {
 
-	return (__softfloat_float_rounding_mode);
+#ifdef FE_TONEAREST
+ 	return FE_TONEAREST;
+#else
+	return 0;
+#endif
+
 }
 
 __fenv_static inline int
 fesetround(int rounding_mode)
 {
 
-	__softfloat_float_rounding_mode = rounding_mode;
 	return (0);
 }
 
@@ -114,19 +111,13 @@  __fenv_static inline int
 fegetenv(fenv_t *envp)
 {
 
-	__set_env(*envp, __softfloat_float_exception_flags,
-	    __softfloat_float_exception_mask, __softfloat_float_rounding_mode);
 	return (0);
 }
 
 __fenv_static inline int
 feholdexcept(fenv_t *envp)
 {
-	fenv_t __env;
-
-	fegetenv(envp);
-	__softfloat_float_exception_flags = 0;
-	__softfloat_float_exception_mask = 0;
+
 	return (0);
 }
 
@@ -134,19 +125,19 @@  __fenv_static inline int
 fesetenv(const fenv_t *envp)
 {
 
-	__softfloat_float_exception_flags = __env_flags(*envp);
-	__softfloat_float_exception_mask = __env_mask(*envp);
-	__softfloat_float_rounding_mode = __env_round(*envp);
+
 	return (0);
 }
 
 __fenv_static inline int
 feupdateenv(const fenv_t *envp)
 {
-	int __oflags = __softfloat_float_exception_flags;
 
-	fesetenv(envp);
-	feraiseexcept(__oflags);
+#if defined FE_NOMASK_ENV && FE_ALL_EXCEPT != 0
+	  if (envp == FE_NOMASK_ENV)
+	      return 1;
+#endif
+
 	return (0);
 }
 
@@ -157,26 +148,22 @@  feupdateenv(const fenv_t *envp)
 __fenv_static inline int
 feenableexcept(int __mask)
 {
-	int __omask = __softfloat_float_exception_mask;
-
-	__softfloat_float_exception_mask |= __mask;
-	return (__omask);
+
+	return (0);
 }
 
 __fenv_static inline int
 fedisableexcept(int __mask)
 {
-	int __omask = __softfloat_float_exception_mask;
-
-	__softfloat_float_exception_mask &= ~__mask;
-	return (__omask);
+
+	return (0);
 }
 
 __fenv_static inline int
 fegetexcept(void)
 {
 
-	return (__softfloat_float_exception_mask);
+	return (0);
 }
 
 #endif /* __BSD_VISIBLE */
diff --git a/newlib/libm/machine/mips/fenv.c b/newlib/libm/machine/mips/fenv.c
index 6e4bb8f33..e2179eb20 100644
--- a/newlib/libm/machine/mips/fenv.c
+++ b/newlib/libm/machine/mips/fenv.c
@@ -44,20 +44,10 @@ 
  * this as a default environment.
  */
 
-
 #ifdef	__mips_soft_float
-#define __set_env(env, flags, mask, rnd) env = ((flags)                 \
-                                                | (mask)<<_FPUSW_SHIFT  \
-                                                | (rnd) << 24)
-#define __env_flags(env)                ((env) & FE_ALL_EXCEPT)
-#define __env_mask(env)                 (((env) >> _FPUSW_SHIFT)        \
-                                                & FE_ALL_EXCEPT)
-#define __env_round(env)                (((env) >> 24) & _ROUND_MASK)
 #include <machine/fenv-softfloat.h>
 #endif
 
-
-
 extern inline int feclearexcept(int excepts);
 extern inline int fegetexceptflag(fexcept_t *flagp, int excepts);
 extern inline int fesetexceptflag(const fexcept_t *flagp, int excepts);