1 //=== lib/fp_trunc.h - high precision -> low 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 precision setting 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef FP_TRUNC_HEADER 15 #define FP_TRUNC_HEADER 16 17 #include "int_lib.h" 18 19 #if defined SRC_SINGLE 20 typedef float src_t; 21 typedef uint32_t src_rep_t; 22 #define SRC_REP_C UINT32_C 23 static const int srcSigBits = 23; 24 25 #elif defined SRC_DOUBLE 26 typedef double src_t; 27 typedef uint64_t src_rep_t; 28 #define SRC_REP_C UINT64_C 29 static const int srcSigBits = 52; 30 31 #elif defined SRC_QUAD 32 typedef long double src_t; 33 typedef __uint128_t src_rep_t; 34 #define SRC_REP_C (__uint128_t) 35 static const int srcSigBits = 112; 36 37 #else 38 #error Source should be double precision or quad precision! 39 #endif //end source precision 40 41 #if defined DST_DOUBLE 42 typedef double dst_t; 43 typedef uint64_t dst_rep_t; 44 #define DST_REP_C UINT64_C 45 static const int dstSigBits = 52; 46 47 #elif defined DST_SINGLE 48 typedef float dst_t; 49 typedef uint32_t dst_rep_t; 50 #define DST_REP_C UINT32_C 51 static const int dstSigBits = 23; 52 53 #elif defined DST_HALF 54 typedef uint16_t dst_t; 55 typedef uint16_t dst_rep_t; 56 #define DST_REP_C UINT16_C 57 static const int dstSigBits = 10; 58 59 #else 60 #error Destination should be single precision or double precision! 61 #endif //end destination precision 62 63 // End of specialization parameters. Two helper routines for conversion to and 64 // from the representation of floating-point data as integer values follow. 65 66 static __inline src_rep_t srcToRep(src_t x) { 67 const union { src_t f; src_rep_t i; } rep = {.f = x}; 68 return rep.i; 69 } 70 71 static __inline dst_t dstFromRep(dst_rep_t x) { 72 const union { dst_t f; dst_rep_t i; } rep = {.i = x}; 73 return rep.f; 74 } 75 76 #endif // FP_TRUNC_HEADER 77
