1 /*
2  * Single-precision math error handling.
3  *
4  * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5  * See https://llvm.org/LICENSE.txt for license information.
6  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7  */
8 
9 #include "math_config.h"
10 
11 #if WANT_ERRNO
12 #include <errno.h>
13 /* NOINLINE reduces code size and avoids making math functions non-leaf
14    when the error handling is inlined.  */
15 NOINLINE static float
with_errnof(float y,int e)16 with_errnof (float y, int e)
17 {
18   errno = e;
19   return y;
20 }
21 #else
22 #define with_errnof(x, e) (x)
23 #endif
24 
25 /* NOINLINE reduces code size.  */
26 NOINLINE static float
xflowf(uint32_t sign,float y)27 xflowf (uint32_t sign, float y)
28 {
29   y = eval_as_float (opt_barrier_float (sign ? -y : y) * y);
30   return with_errnof (y, ERANGE);
31 }
32 
33 HIDDEN float
__math_uflowf(uint32_t sign)34 __math_uflowf (uint32_t sign)
35 {
36   return xflowf (sign, 0x1p-95f);
37 }
38 
39 #if WANT_ERRNO_UFLOW
40 /* Underflows to zero in some non-nearest rounding mode, setting errno
41    is valid even if the result is non-zero, but in the subnormal range.  */
42 HIDDEN float
__math_may_uflowf(uint32_t sign)43 __math_may_uflowf (uint32_t sign)
44 {
45   return xflowf (sign, 0x1.4p-75f);
46 }
47 #endif
48 
49 HIDDEN float
__math_oflowf(uint32_t sign)50 __math_oflowf (uint32_t sign)
51 {
52   return xflowf (sign, 0x1p97f);
53 }
54 
55 HIDDEN float
__math_divzerof(uint32_t sign)56 __math_divzerof (uint32_t sign)
57 {
58   float y = opt_barrier_float (sign ? -1.0f : 1.0f) / 0.0f;
59   return with_errnof (y, ERANGE);
60 }
61 
62 HIDDEN float
__math_invalidf(float x)63 __math_invalidf (float x)
64 {
65   float y = (x - x) / (x - x);
66   return isnan (x) ? y : with_errnof (y, EDOM);
67 }
68