msun fixes for SPE

Summary:
Fix FPU exception management for powerpcspe.  Bits are in a different place from
the standard FPSCR, so we need to handle the shifting differences.  Also,
there's no concept of a "software exception" raise, so we need to do exceptional
math to trigger the exception from software.

Reviewed By: alfredo
Differential Revision: https://reviews.freebsd.org/D22824
This commit is contained in:
Justin Hibbits 2021-05-05 09:20:56 -05:00
parent d1cb8d11b0
commit 6640579610
2 changed files with 48 additions and 1 deletions

View File

@ -30,6 +30,10 @@
#define __fenv_static
#include "fenv.h"
#ifdef __SPE__
#include <sys/types.h>
#include <machine/spr.h>
#endif
#ifdef __GNUC_GNU_INLINE__
#error "This file must be compiled with C99 'inline' semantics"
@ -40,7 +44,9 @@ const fenv_t __fe_dfl_env = 0x00000000;
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);
#ifndef __SPE__
extern inline int feraiseexcept(int __excepts);
#endif
extern inline int fetestexcept(int __excepts);
extern inline int fegetround(void);
extern inline int fesetround(int __round);
@ -48,3 +54,27 @@ extern inline int fegetenv(fenv_t *__envp);
extern inline int feholdexcept(fenv_t *__envp);
extern inline int fesetenv(const fenv_t *__envp);
extern inline int feupdateenv(const fenv_t *__envp);
#ifdef __SPE__
#define PMAX 0x7f7fffff
#define PMIN 0x00800000
int feraiseexcept(int __excepts)
{
uint32_t spefscr;
spefscr = mfspr(SPR_SPEFSCR);
mtspr(SPR_SPEFSCR, spefscr | (__excepts & FE_ALL_EXCEPT));
if (__excepts & FE_INVALID)
__asm __volatile ("efsdiv %0, %0, %1" :: "r"(0), "r"(0));
if (__excepts & FE_DIVBYZERO)
__asm __volatile ("efsdiv %0, %0, %1" :: "r"(1.0f), "r"(0));
if (__excepts & FE_UNDERFLOW)
__asm __volatile ("efsmul %0, %0, %0" :: "r"(PMIN));
if (__excepts & FE_OVERFLOW)
__asm __volatile ("efsadd %0, %0, %0" :: "r"(PMAX));
if (__excepts & FE_INEXACT)
__asm __volatile ("efssub %0, %0, %1" :: "r"(PMIN), "r"(1.0f));
return (0);
}
#endif

View File

@ -42,6 +42,17 @@ typedef __uint32_t fenv_t;
typedef __uint32_t fexcept_t;
/* Exception flags */
#ifdef __SPE__
#define FE_OVERFLOW 0x00000100
#define FE_UNDERFLOW 0x00000200
#define FE_DIVBYZERO 0x00000400
#define FE_INVALID 0x00000800
#define FE_INEXACT 0x00001000
#define FE_ALL_INVALID FE_INVALID
#define _FPUSW_SHIFT 6
#else
#define FE_INEXACT 0x02000000
#define FE_DIVBYZERO 0x04000000
#define FE_UNDERFLOW 0x08000000
@ -67,6 +78,9 @@ typedef __uint32_t fexcept_t;
#define FE_ALL_INVALID (FE_VXCVI | FE_VXSQRT | FE_VXSOFT | FE_VXVC | \
FE_VXIMZ | FE_VXZDZ | FE_VXIDI | FE_VXISI | \
FE_VXSNAN | FE_INVALID)
#define _FPUSW_SHIFT 22
#endif
#define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | \
FE_ALL_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
@ -85,7 +99,6 @@ 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 */
#define _FPUSW_SHIFT 22
#define _ENABLE_MASK ((FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
FE_OVERFLOW | FE_UNDERFLOW) >> _FPUSW_SHIFT)
@ -156,6 +169,9 @@ fesetexceptflag(const fexcept_t *__flagp, int __excepts)
return (0);
}
#ifdef __SPE__
extern int feraiseexcept(int __excepts);
#else
__fenv_static inline int
feraiseexcept(int __excepts)
{
@ -168,6 +184,7 @@ feraiseexcept(int __excepts)
__mtfsf(__r);
return (0);
}
#endif
__fenv_static inline int
fetestexcept(int __excepts)