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Diffstat (limited to 'newlib/libm/common/fdlibm.h')
| -rw-r--r-- | newlib/libm/common/fdlibm.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/newlib/libm/common/fdlibm.h b/newlib/libm/common/fdlibm.h index 3877ff2dc..ab0ada1a1 100644 --- a/newlib/libm/common/fdlibm.h +++ b/newlib/libm/common/fdlibm.h @@ -361,3 +361,13 @@ do { \ sf_u.word = (i); \ (d) = sf_u.value; \ } while (0) + +/* Macros to avoid undefined behaviour that can arise if the amount + of a shift is exactly equal to the size of the shifted operand. */ + +#define SAFE_LEFT_SHIFT(op,amt) \ + (((amt) < 8 * sizeof(op)) ? ((op) << (amt)) : 0) + +#define SAFE_RIGHT_SHIFT(op,amt) \ + (((amt) < 8 * sizeof(op)) ? ((op) >> (amt)) : 0) + |