#include #include "cpu_features.h" /* 7.6.3.2 The fesetround function establishes the rounding direction represented by its argument round. If the argument is not equal to the value of a rounding direction macro, the rounding direction is not changed. */ int fesetround (int mode) { unsigned short _cw; if ((mode & ~(FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | FE_TOWARDZERO)) != 0) return -1; __asm__ volatile ("fnstcw %0;": "=m" (_cw)); _cw &= ~(FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | FE_TOWARDZERO); _cw |= mode; __asm__ volatile ("fldcw %0;" : : "m" (_cw)); if (__HAS_SSE) { __asm__ volatile ("stmxcsr %0" : "=m" (_cw)); _cw &= ~ 0x6000; _cw |= (mode << __MXCSR_ROUND_FLAG_SHIFT); __asm__ volatile ("ldmxcsr %0" : : "m" (_cw)); } return 0; }