1 //===-lib/fp_extend.h - low precision -> high precision conversion -*- C 2 //-*-===// 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 // 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 uint32_t src_rep_t; 22 #define SRC_REP_C UINT32_C 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 uint64_t src_rep_t; 29 #define SRC_REP_C UINT64_C 30 static const int srcSigBits = 52; 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 uint32_t dst_rep_t; 56 #define DST_REP_C UINT32_C 57 static const int dstSigBits = 23; 58 59 #elif defined DST_DOUBLE 60 typedef double dst_t; 61 typedef uint64_t dst_rep_t; 62 #define DST_REP_C UINT64_C 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 78 static __inline src_rep_t srcToRep(src_t x) { 79 const union { 80 src_t f; 81 src_rep_t i; 82 } rep = {.f = x}; 83 return rep.i; 84 } 85 86 static __inline dst_t dstFromRep(dst_rep_t x) { 87 const union { 88 dst_t f; 89 dst_rep_t i; 90 } rep = {.i = x}; 91 return rep.f; 92 } 93 // End helper routines. Conversion implementation follows. 94 95 #endif // FP_EXTEND_HEADER 96