Changeset 96201 in vbox for trunk/include/iprt/nocrt/x86

Timestamp:

Aug 14, 2022 3:26:28 AM (2 years ago)

Author:

vboxsync

Message:

IPRT/nocrt: Implemented fegetround and fesetround to workaround the MSC versions not modifying FCW in 64-bit mode and impeding testing. bugref:10261

File:

• trunk/include/iprt/nocrt/x86/fenv.h (modified) (6 diffs)

trunk/include/iprt/nocrt/x86/fenv.h

@@ -84 +84 @@
 
 /* Exception flags */
-#define FE_INVALID  0x01
-#define FE_DENORMAL 0x02
+#define FE_INVALID      0x01
+#define FE_DENORMAL     0x02
 #define FE_DIVBYZERO    0x04
-#define FE_OVERFLOW 0x08
+#define FE_OVERFLOW     0x08
 #define FE_UNDERFLOW    0x10
-#define FE_INEXACT  0x20
-#define FE_ALL_EXCEPT   (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \
-             FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
-
-/* Rounding modes */
+#define FE_INEXACT      0x20
+#define FE_ALL_EXCEPT   (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT \
+                         | FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
+
+/* Rounding modes (x87 constants) */
 #define FE_TONEAREST    0x0000
-#define FE_DOWNWARD 0x0400
-#define FE_UPWARD   0x0800
+#define FE_DOWNWARD     0x0400
+#define FE_UPWARD       0x0800
 #define FE_TOWARDZERO   0x0c00
-#define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \
-             FE_UPWARD | FE_TOWARDZERO)
+#define _ROUND_MASK     0x0c00
 
 /*
@@ -125 +124 @@
 extern const fenv_t __fe_dfl_env;
 #define FE_DFL_ENV  (&__fe_dfl_env)
+
+#ifdef __GNUC__
 
 #define __fldcw(__cw)       __asm __volatile("fldcw %0" : : "m" (__cw))
@@ -176 +177 @@
 }
 
-int RT_NOCRT(fesetexceptflag)(const fexcept_t *__flagp, int __excepts);
-int RT_NOCRT(feraiseexcept)(int __excepts);
-
 DECLINLINE(int)
 fetestexcept(int __excepts)
@@ -193 +191 @@
 
 DECLINLINE(int)
-fegetround(void)
-{
-    int __control;
-
-    /*
-     * We assume that the x87 and the SSE unit agree on the
-     * rounding mode.  Reading the control word on the x87 turns
-     * out to be about 5 times faster than reading it on the SSE
-     * unit on an Opteron 244.
-     */
-    __fnstcw(&__control);
-    return (__control & _ROUND_MASK);
-}
-
-DECLINLINE(int)
-fesetround(int __round)
-{
-    int __mxcsr, __control;
-
-    if (__round & ~_ROUND_MASK)
-        return (-1);
-
-    __fnstcw(&__control);
-    __control &= ~_ROUND_MASK;
-    __control |= __round;
-    __fldcw(__control);
-
-    if (__HAS_SSE()) {
-        __stmxcsr(&__mxcsr);
-        __mxcsr &= ~(_ROUND_MASK << _SSE_ROUND_SHIFT);
-        __mxcsr |= __round << _SSE_ROUND_SHIFT;
-        __ldmxcsr(__mxcsr);
-    }
-
-    return (0);
-}
-
-int RT_NOCRT(fegetenv)(fenv_t *__envp);
-int RT_NOCRT(feholdexcept)(fenv_t *__envp);
-
-DECLINLINE(int)
 fesetenv(const fenv_t *__envp)
 {
@@ -247 +204 @@
 }
 
-int RT_NOCRT(feupdateenv)(const fenv_t *__envp);
-int RT_NOCRT(feenableexcept)(int __mask);
-int RT_NOCRT(fedisableexcept)(int __mask);
-
 DECLINLINE(int)
 fegetexcept(void)
@@ -267 +220 @@
 # pragma GCC diagnostic pop
 #endif
+
+#endif /* __GNUC__ */
+
+int RT_NOCRT(fesetexceptflag)(const fexcept_t *__flagp, int __excepts);
+int RT_NOCRT(feraiseexcept)(int __excepts);
+int RT_NOCRT(fegetround)(void);
+int RT_NOCRT(fesetround)(int);
+int RT_NOCRT(fegetenv)(fenv_t *__envp);
+int RT_NOCRT(feholdexcept)(fenv_t *__envp);
+int RT_NOCRT(feupdateenv)(const fenv_t *__envp);
+int RT_NOCRT(feenableexcept)(int __mask);
+int RT_NOCRT(fedisableexcept)(int __mask);
+
 
 RT_C_DECLS_END