support setting fpu precision on m68k (closes #20904)
Patch from Andreas Schwab.
diff --git a/Include/pyport.h b/Include/pyport.h
index c706213..69deb9f 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -588,6 +588,25 @@
} while (0)
#endif
+#ifdef HAVE_GCC_ASM_FOR_MC68881
+#define HAVE_PY_SET_53BIT_PRECISION 1
+#define _Py_SET_53BIT_PRECISION_HEADER \
+ unsigned int old_fpcr, new_fpcr
+#define _Py_SET_53BIT_PRECISION_START \
+ do { \
+ __asm__ ("fmove.l %%fpcr,%0" : "=g" (old_fpcr)); \
+ /* Set double precision / round to nearest. */ \
+ new_fpcr = (old_fpcr & ~0xf0) | 0x80; \
+ if (new_fpcr != old_fpcr) \
+ __asm__ volatile ("fmove.l %0,%%fpcr" : : "g" (new_fpcr)); \
+ } while (0)
+#define _Py_SET_53BIT_PRECISION_END \
+ do { \
+ if (new_fpcr != old_fpcr) \
+ __asm__ volatile ("fmove.l %0,%%fpcr" : : "g" (old_fpcr)); \
+ } while (0)
+#endif
+
/* default definitions are empty */
#ifndef HAVE_PY_SET_53BIT_PRECISION
#define _Py_SET_53BIT_PRECISION_HEADER