fclexaxp.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 66 行

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*                            Open Watcom Project
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#include "rtdata.h"
#include "variety.h"
#include "clearfpe.h"


extern unsigned long _GetFPCR(void);
extern void          _SetFPCR(unsigned long);


/*
 * Alpha FPCR Exception Bits
 * -------------------------
 *
 * Bit 63 : Summary Bit (OR of Bits 57 - 52)
 * Bit 57 : Integer Overflow (IOV) Exception
 * Bit 56 : Inexact Result (INE) Exception
 * Bit 55 : Underflow (UNF) Exception
 * Bit 54 : Overflow (OVF) Exception
 * Bit 53 : Division by Zero (DZE) Exception
 * Bit 52 : Invalid Operation (INV) Exception
 *
 * Since we are using only the highword of the FPCR, these bits will map
 * to 31 and 25-20 respectively.
 */

void _ClearFPE(void)
{
    unsigned long fpcr;

    fpcr = _GetFPCR();
    fpcr &= 0x7c0fffffL;
    _SetFPCR(fpcr);
} /* _ClearFPE() */