arm: Fix fenv support

The previous fenv support for ARM used the soft-float implementation of
FreeBSD.  Newlib uses the one from libgcc by default.  They are not
compatible.  Having an GCC incompatible soft-float fenv support in
Newlib makes no sense.  A long-term solution could be to provide a
libgcc compatible soft-float support.  This likely requires changes in
the GCC configuration.  For now, provide a stub implementation for
soft-float multilibs similar to RISC-V.

Move implementation to one file and delete now unused files.  Hide
implementation details.  Remove function parameter names from header
file to avoid name conflicts.

Provide VFP support if __SOFTFP__ is not defined like glibc.

Reviewed-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
Signed-off-by: Eshan dhawan <eshandhawan51@gmail.com>

4 files changed, 17 insertions, 476 deletions

diff --git a/newlib/libc/machine/arm/machine/fenv-mangle.h b/newlib/libc/machine/arm/machine/fenv-mangle.h
deleted file mode 100644
index 476f7b20c..000000000
--- a/newlib/libc/machine/arm/machine/fenv-mangle.h
+++ /dev/null
@@ -1,53 +0,0 @@
-/*-
- * Copyright (c) 2013 Andrew Turner <andrew@FreeBSD.ORG>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
-
-#ifdef _FENV_MANGLE_H_
-#error Only include fenv-mangle.h once
-#endif
-
-#define	_FENV_MANGLE_H_
-
-#ifndef FENV_MANGLE
-#error FENV_MANGLE is undefined
-#endif
-
-#define	feclearexcept	FENV_MANGLE(feclearexcept)
-#define	fegetexceptflag	FENV_MANGLE(fegetexceptflag)
-#define	fesetexceptflag	FENV_MANGLE(fesetexceptflag)
-#define	feraiseexcept	FENV_MANGLE(feraiseexcept)
-#define	fetestexcept	FENV_MANGLE(fetestexcept)
-#define	fegetround	FENV_MANGLE(fegetround)
-#define	fesetround	FENV_MANGLE(fesetround)
-#define	fegetenv	FENV_MANGLE(fegetenv)
-#define	feholdexcept	FENV_MANGLE(feholdexcept)
-#define	fesetenv	FENV_MANGLE(fesetenv)
-#define	feupdateenv	FENV_MANGLE(feupdateenv)
-#define	feenableexcept	FENV_MANGLE(feenableexcept)
-#define	fedisableexcept	FENV_MANGLE(fedisableexcept)
-#define	fegetexcept	FENV_MANGLE(fegetexcept)
-
diff --git a/newlib/libc/machine/arm/machine/fenv-softfloat.h b/newlib/libc/machine/arm/machine/fenv-softfloat.h
deleted file mode 100644
index 5d33e18d0..000000000
--- a/newlib/libc/machine/arm/machine/fenv-softfloat.h
+++ /dev/null
@@ -1,187 +0,0 @@
- /*-
- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
- *
- * Copyright (c) 2004-2011 David Schultz <das@FreeBSD.ORG>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
-
-#ifndef	_SYS_FENV_H_
-#error "This file is meant to be included only by <sys/fenv.h>."
-#endif
-/* the file can be added from architecture specific fenv.h file found in
- *libc/sys/arch/sys *
- *
- * This file implements the functionality of <fenv.h> on platforms that
- * lack an FPU and use softfloat in libc for floating point.  To use it,
- * you must write an <fenv.h> that provides the following:
- *
- *   - a typedef for fenv_t, which may be an integer or struct type
- *   - a typedef for fexcept_t (XXX This file assumes fexcept_t is a
- *     simple integer type containing the exception mask.)
- *   - definitions of FE_* constants for the five exceptions and four
- *     rounding modes in IEEE 754, as described in fenv(3)
- *   - a definition, and the corresponding external symbol, for FE_DFL_ENV
- *   - a macro __set_env(env, flags, mask, rnd), which sets the given fenv_t
- *     from the exception flags, mask, and rounding mode
- *   - macros __env_flags(env), __env_mask(env), and __env_round(env), which
- *     extract fields from an fenv_t
- *   - a definition of __fenv_static
- *
- * If the architecture supports an optional FPU, it's recommended that you
- * define fenv_t and fexcept_t to match the hardware ABI.  Otherwise, it
- * 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);
-}
-
-__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);
-}
-
-__fenv_static inline int
-feraiseexcept(int excepts)
-{
-
-	return (excepts  ?  -ENOTSUP : 0);
-}
-
-__fenv_static inline int
-fetestexcept(int excepts)
-{
-
-	return (__softfloat_float_exception_flags & excepts);
-}
-
-__fenv_static inline int
-fegetround(void)
-{
-
-	return (__softfloat_float_rounding_mode);
-}
-
-__fenv_static inline int
-fesetround(int round)
-{
-
-	__softfloat_float_rounding_mode = round;
-	return (0);
-}
-
-__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);
-}
-
-__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);
-	return (0);
-}
-
-#if __BSD_VISIBLE
-
-/* We currently provide no external definitions of the functions below. */
-
-__fenv_static inline int
-feenableexcept(int __mask)
-{
-	int __omask = __softfloat_float_exception_mask;
-
-	__softfloat_float_exception_mask |= __mask;
-	return (__omask);
-}
-
-__fenv_static inline int
-fedisableexcept(int __mask)
-{
-	int __omask = __softfloat_float_exception_mask;
-
-	__softfloat_float_exception_mask &= ~__mask;
-	return (__omask);
-}
-
-__fenv_static inline int
-fegetexcept(void)
-{
-
-	return (__softfloat_float_exception_mask);
-}
-
-#endif /* __BSD_VISIBLE */
diff --git a/newlib/libc/machine/arm/machine/fenv-vfp.h b/newlib/libc/machine/arm/machine/fenv-vfp.h
deleted file mode 100644
index 25d71f3ab..000000000
--- a/newlib/libc/machine/arm/machine/fenv-vfp.h
+++ /dev/null
@@ -1,187 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
- *
- * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
-
-
-
-#define	vmrs_fpscr(__r)	__asm __volatile("vmrs %0, fpscr" : "=&r"(__r))
-#define	vmsr_fpscr(__r)	__asm __volatile("vmsr fpscr, %0" : : "r"(__r))
-
-
-#define _FPU_MASK_SHIFT	8
-
-__fenv_static inline int feclearexcept(int excepts)
-{
-	fexcept_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	__fpsr &= ~excepts;
-	vmsr_fpscr(__fpsr);
-	return (0);
-}
-
-__fenv_static inline int
-fegetexceptflag(fexcept_t *flagp, int excepts)
-{
-	fexcept_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	*flagp = __fpsr & excepts;
-	return (0);
-}
-
-__fenv_static inline int
-fesetexceptflag(const fexcept_t *flagp, int excepts)
-{
-	fexcept_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	__fpsr &= ~excepts;
-	__fpsr |= *flagp & excepts;
-	vmsr_fpscr(__fpsr);
-	return (0);
-}
-
-__fenv_static inline int
-feraiseexcept(int excepts)
-{
-	fexcept_t __ex = excepts;
-
-	fesetexceptflag(&__ex, excepts);	/* XXX */
-	return (0);
-}
-
-__fenv_static inline int
-fetestexcept(int excepts)
-{
-	fexcept_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	return (__fpsr & excepts);
-}
-
-__fenv_static inline int
-fegetround(void)
-{
-	fenv_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	return (__fpsr & _ROUND_MASK);
-}
-
-__fenv_static inline int
-fesetround(int round)
-{
-	fenv_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	__fpsr &= ~(_ROUND_MASK);
-	__fpsr |= round;
-	vmsr_fpscr(__fpsr);
-	return (0);
-}
-
-__fenv_static inline int
-fegetenv(fenv_t *envp)
-{
-
-	vmrs_fpscr(*envp);
-	return (0);
-}
-
-__fenv_static inline int
-feholdexcept(fenv_t *envp)
-{
-	fenv_t __env;
-
-	vmrs_fpscr(__env);
-	*envp = __env;
-	__env &= ~(FE_ALL_EXCEPT);
-	vmsr_fpscr(__env);
-	return (0);
-}
-
-__fenv_static inline int
-fesetenv(const fenv_t *envp)
-{
-
-	vmsr_fpscr(*envp);
-	return (0);
-}
-
-__fenv_static inline int
-feupdateenv(const fenv_t *envp)
-{
-	fexcept_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	vmsr_fpscr(*envp);
-	feraiseexcept(__fpsr & FE_ALL_EXCEPT);
-	return (0);
-}
-
-#if __BSD_VISIBLE
-
-/* We currently provide no external definitions of the functions below. */
-
-__fenv_static inline int
-feenableexcept(int __mask)
-{
-	fenv_t __old_fpsr, __new_fpsr;
-
-	vmrs_fpscr(__old_fpsr);
-	__new_fpsr = __old_fpsr |
-	    ((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
-	vmsr_fpscr(__new_fpsr);
-	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
-}
-
-__fenv_static inline int
-fedisableexcept(int __mask)
-{
-	fenv_t __old_fpsr, __new_fpsr;
-
-	vmrs_fpscr(__old_fpsr);
-	__new_fpsr = __old_fpsr &
-	    ~((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
-	vmsr_fpscr(__new_fpsr);
-	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
-}
-
-__fenv_static inline int
-fegetexcept(void)
-{
-	fenv_t __fpsr;
-
-	vmrs_fpscr(__fpsr);
-	return (__fpsr & FE_ALL_EXCEPT);
-}
-
-#endif /* __BSD_VISIBLE */
-
diff --git a/newlib/libc/machine/arm/sys/fenv.h b/newlib/libc/machine/arm/sys/fenv.h
index 740995a1a..70bd57be4 100644
--- a/newlib/libc/machine/arm/sys/fenv.h
+++ b/newlib/libc/machine/arm/sys/fenv.h
@@ -38,10 +38,6 @@
 extern "C" {
 #endif
 
-#ifndef	__fenv_static
-#define	__fenv_static static
-#endif
-
 typedef int fenv_t;
 typedef int fexcept_t;
 
@@ -51,7 +47,7 @@ typedef int fexcept_t;
 #define	FE_OVERFLOW	0x0004
 #define	FE_UNDERFLOW	0x0008
 #define	FE_INEXACT	0x0010
-#ifdef __ARM_PCS_VFP
+#ifndef __SOFTFP__
 #define	FE_DENORMAL	0x0080
 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW | FE_DENORMAL)
@@ -60,61 +56,33 @@ typedef int fexcept_t;
 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
 #endif
 
-
-
 /* Rounding modes */
-#define	VFP_FE_TONEAREST	0x00000000
-#define	VFP_FE_UPWARD		0x00400000
-#define	VFP_FE_DOWNWARD		0x00800000
-#define	VFP_FE_TOWARDZERO	0x00c00000
-
-#ifdef __ARM_PCS_VFP
-#define	FE_TONEAREST	VFP_FE_TONEAREST
-#define	FE_UPWARD	VFP_FE_UPWARD
-#define	FE_DOWNWARD	VFP_FE_DOWNWARD
-#define	FE_TOWARDZERO	VFP_FE_TOWARDZERO
-#else
-#define	FE_TONEAREST	0x0000
-#define	FE_TOWARDZERO	0x0001
-#define	FE_UPWARD	0x0002
-#define	FE_DOWNWARD	0x0003
-#endif
-#define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
-			 FE_UPWARD | FE_TOWARDZERO)
-
+#define	FE_TONEAREST		0x00000000
+#define	FE_UPWARD		0x00400000
+#define	FE_DOWNWARD		0x00800000
+#define	FE_TOWARDZERO		0x00c00000
 
 /* Default floating-point environment */
-
 extern const fenv_t	*_fe_dfl_env;
 #define	FE_DFL_ENV	(_fe_dfl_env)
 
-/* We need to be able to map status flag positions to mask flag positions */
-#ifndef __ARM_PCS_VFP
-#define	_FPUSW_SHIFT	16
-#define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)
-#endif
-
-
-
-int feclearexcept(int excepts);
-int fegetexceptflag(fexcept_t *flagp, int excepts);
-int fesetexceptflag(const fexcept_t *flagp, int excepts);
-int feraiseexcept(int excepts);
-int fetestexcept(int excepts);
+int feclearexcept(int);
+int fegetexceptflag(fexcept_t *, int);
+int fesetexceptflag(const fexcept_t *, int);
+int feraiseexcept(int);
+int fetestexcept(int);
 int fegetround(void);
-int fesetround(int round);
-int fegetenv(fenv_t *envp);
-int feholdexcept(fenv_t *envp);
-int fesetenv(const fenv_t *envp);
-int feupdateenv(const fenv_t *envp);
+int fesetround(int);
+int fegetenv(fenv_t *);
+int feholdexcept(fenv_t *);
+int fesetenv(const fenv_t *);
+int feupdateenv(const fenv_t *);
 #if __BSD_VISIBLE
-int feenableexcept(int __mask);
-int fedisableexcept(int __mask);
+int feenableexcept(int);
+int fedisableexcept(int);
 int fegetexcept(void);
 #endif /* __BSD_VISIBLE */
 
-
-
 #ifdef __cplusplus
 }
 #endif