| //===-- lib/floatunsidf.c - uint -> double-precision conversion ---*- C -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements unsigned integer to double-precision conversion for the |
| // compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even |
| // mode. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DOUBLE_PRECISION |
| #include "fp_lib.h" |
| |
| #include "int_lib.h" |
| |
| COMPILER_RT_ABI fp_t |
| __floatunsidf(unsigned int a) { |
| |
| const int aWidth = sizeof a * CHAR_BIT; |
| |
| // Handle zero as a special case to protect clz |
| if (a == 0) return fromRep(0); |
| |
| // Exponent of (fp_t)a is the width of abs(a). |
| const int exponent = (aWidth - 1) - __builtin_clz(a); |
| rep_t result; |
| |
| // Shift a into the significand field and clear the implicit bit. |
| const int shift = significandBits - exponent; |
| result = (rep_t)a << shift ^ implicitBit; |
| |
| // Insert the exponent |
| result += (rep_t)(exponent + exponentBias) << significandBits; |
| return fromRep(result); |
| } |
| |
| #if defined(__ARM_EABI__) |
| #if defined(COMPILER_RT_ARMHF_TARGET) |
| AEABI_RTABI fp_t __aeabi_ui2d(unsigned int a) { |
| return __floatunsidf(a); |
| } |
| #else |
| AEABI_RTABI fp_t __aeabi_ui2d(unsigned int a) COMPILER_RT_ALIAS(__floatunsidf); |
| #endif |
| #endif |
