1 //===-lib/fp_extend.h - low precision -> high precision conversion -*- C -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Set source and destination setting
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef FP_EXTEND_HEADER
15 #define FP_EXTEND_HEADER
16 
17 #include "int_lib.h"
18 
19 #if defined SRC_SINGLE
20 typedef float src_t;
21 typedef su_int src_rep_t;
22 #define SRC_REP_C(c) c ## UL
23 static const int srcSigBits = 23;
24 #define src_rep_t_clz __builtin_clz
25 
26 #elif defined SRC_DOUBLE
27 typedef double src_t;
28 typedef du_int src_rep_t;
29 #define SRC_REP_C(c) c ## ULL
30 static const int srcSigBits = 52;
src_rep_t_clz(src_rep_t a)31 static __inline int src_rep_t_clz(src_rep_t a) {
32 #if defined __LP64__
33     return __builtin_clzl(a);
34 #else
35     if (a & REP_C(0xffffffff00000000))
36         return __builtin_clz(a >> 32);
37     else
38         return 32 + __builtin_clz(a & REP_C(0xffffffff));
39 #endif
40 }
41 
42 #elif defined SRC_HALF
43 typedef uint16_t src_t;
44 typedef uint16_t src_rep_t;
45 #define SRC_REP_C UINT16_C
46 static const int srcSigBits = 10;
47 #define src_rep_t_clz __builtin_clz
48 
49 #else
50 #error Source should be half, single, or double precision!
51 #endif //end source precision
52 
53 #if defined DST_SINGLE
54 typedef float dst_t;
55 typedef su_int dst_rep_t;
56 #define DST_REP_C(c) c ## UL
57 static const int dstSigBits = 23;
58 
59 #elif defined DST_DOUBLE
60 typedef double dst_t;
61 typedef du_int dst_rep_t;
62 #define DST_REP_C(c) c ## ULL
63 static const int dstSigBits = 52;
64 
65 #elif defined DST_QUAD
66 typedef long double dst_t;
67 typedef __uint128_t dst_rep_t;
68 #define DST_REP_C (__uint128_t)
69 static const int dstSigBits = 112;
70 
71 #else
72 #error Destination should be single, double, or quad precision!
73 #endif //end destination precision
74 
75 // End of specialization parameters.  Two helper routines for conversion to and
76 // from the representation of floating-point data as integer values follow.
77 
srcToRep(src_t x)78 static __inline src_rep_t srcToRep(src_t x) {
79     const union { src_t f; src_rep_t i; } rep = {.f = x};
80     return rep.i;
81 }
82 
dstFromRep(dst_rep_t x)83 static __inline dst_t dstFromRep(dst_rep_t x) {
84     const union { dst_t f; dst_rep_t i; } rep = {.i = x};
85     return rep.f;
86 }
87 // End helper routines.  Conversion implementation follows.
88 
89 #endif //FP_EXTEND_HEADER
90