diff options
Diffstat (limited to 'src/math/expf.c')
| -rw-r--r-- | src/math/expf.c | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/src/math/expf.c b/src/math/expf.c index 8aefc917..5572bbf6 100644 --- a/src/math/expf.c +++ b/src/math/expf.c @@ -29,7 +29,7 @@ P2 = -2.7667332906e-3f; /* -0xb55215.0p-32 */ float expf(float x) { - float hi, lo, c, xx; + float_t hi, lo, c, xx, y; int k, sign; uint32_t hx; @@ -38,20 +38,17 @@ float expf(float x) hx &= 0x7fffffff; /* high word of |x| */ /* special cases */ - if (hx >= 0x42b17218) { /* if |x| >= 88.722839f or NaN */ - if (hx > 0x7f800000) /* NaN */ - return x; - if (!sign) { - /* overflow if x!=inf */ + if (hx >= 0x42aeac50) { /* if |x| >= -87.33655f or NaN */ + if (hx >= 0x42b17218 && !sign) { /* x >= 88.722839f */ + /* overflow */ STRICT_ASSIGN(float, x, x * 0x1p127f); return x; } - if (hx == 0x7f800000) /* -inf */ - return 0; - if (hx >= 0x42cff1b5) { /* x <= -103.972084f */ + if (sign) { /* underflow */ - STRICT_ASSIGN(float, x, 0x1p-100f*0x1p-100f); - return x; + FORCE_EVAL(-0x1p-149f/x); + if (hx >= 0x42cff1b5) /* x <= -103.972084f */ + return 0; } } @@ -77,8 +74,8 @@ float expf(float x) /* x is now in primary range */ xx = x*x; c = x - xx*(P1+xx*P2); - x = 1 + (x*c/(2-c) - lo + hi); + y = 1 + (x*c/(2-c) - lo + hi); if (k == 0) - return x; - return scalbnf(x, k); + return y; + return scalbnf(y, k); } |