1*0a6a1f1dSLionel Sambuc /* ===-- floatdixf.c - Implement __floatdixf -------------------------------=== 2*0a6a1f1dSLionel Sambuc * 3*0a6a1f1dSLionel Sambuc * The LLVM Compiler Infrastructure 4*0a6a1f1dSLionel Sambuc * 5*0a6a1f1dSLionel Sambuc * This file is dual licensed under the MIT and the University of Illinois Open 6*0a6a1f1dSLionel Sambuc * Source Licenses. See LICENSE.TXT for details. 7*0a6a1f1dSLionel Sambuc * 8*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 9*0a6a1f1dSLionel Sambuc * 10*0a6a1f1dSLionel Sambuc * This file implements __floatdixf for the compiler_rt library. 11*0a6a1f1dSLionel Sambuc * 12*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 13*0a6a1f1dSLionel Sambuc */ 14*0a6a1f1dSLionel Sambuc 15*0a6a1f1dSLionel Sambuc #if !_ARCH_PPC 16*0a6a1f1dSLionel Sambuc 17*0a6a1f1dSLionel Sambuc #include "int_lib.h" 18*0a6a1f1dSLionel Sambuc 19*0a6a1f1dSLionel Sambuc /* Returns: convert a to a long double, rounding toward even. */ 20*0a6a1f1dSLionel Sambuc 21*0a6a1f1dSLionel Sambuc /* Assumption: long double is a IEEE 80 bit floating point type padded to 128 bits 22*0a6a1f1dSLionel Sambuc * di_int is a 64 bit integral type 23*0a6a1f1dSLionel Sambuc */ 24*0a6a1f1dSLionel Sambuc 25*0a6a1f1dSLionel Sambuc /* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee | 26*0a6a1f1dSLionel Sambuc * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm 27*0a6a1f1dSLionel Sambuc */ 28*0a6a1f1dSLionel Sambuc 29*0a6a1f1dSLionel Sambuc COMPILER_RT_ABI long double __floatdixf(di_int a)30*0a6a1f1dSLionel Sambuc__floatdixf(di_int a) 31*0a6a1f1dSLionel Sambuc { 32*0a6a1f1dSLionel Sambuc if (a == 0) 33*0a6a1f1dSLionel Sambuc return 0.0; 34*0a6a1f1dSLionel Sambuc const unsigned N = sizeof(di_int) * CHAR_BIT; 35*0a6a1f1dSLionel Sambuc const di_int s = a >> (N-1); 36*0a6a1f1dSLionel Sambuc a = (a ^ s) - s; 37*0a6a1f1dSLionel Sambuc int clz = __builtin_clzll(a); 38*0a6a1f1dSLionel Sambuc int e = (N - 1) - clz ; /* exponent */ 39*0a6a1f1dSLionel Sambuc long_double_bits fb; 40*0a6a1f1dSLionel Sambuc fb.u.high.s.low = ((su_int)s & 0x00008000) | /* sign */ 41*0a6a1f1dSLionel Sambuc (e + 16383); /* exponent */ 42*0a6a1f1dSLionel Sambuc fb.u.low.all = a << clz; /* mantissa */ 43*0a6a1f1dSLionel Sambuc return fb.f; 44*0a6a1f1dSLionel Sambuc } 45*0a6a1f1dSLionel Sambuc 46*0a6a1f1dSLionel Sambuc #endif /* !_ARCH_PPC */ 47