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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1906 | serge | 1 | #include |
| 2 | |||
| 3 | /* 'fxam' sets FPU flags C3,C2,C0 'fstsw' stores: |
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| 4 | FP_NAN 001 0x0100 |
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| 5 | FP_NORMAL 010 0x0400 |
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| 6 | FP_INFINITE 011 0x0500 |
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| 7 | FP_ZERO 100 0x4000 |
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| 8 | FP_SUBNORMAL 110 0x4400 |
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| 9 | |||
| 10 | and sets C1 flag (signbit) if neg */ |
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| 11 | |||
| 12 | int __fpclassify (double _x){ |
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| 13 | unsigned short sw; |
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| 14 | __asm__ ( |
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| 15 | "fxam; fstsw %%ax;" |
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| 16 | : "=a" (sw) |
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| 17 | : "t" (_x) |
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| 18 | ); |
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| 19 | return sw & (FP_NAN | FP_NORMAL | FP_ZERO ); |
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| 20 | } |