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//===-- lib/comparetf2.c - Quad-precision comparisons -------------*- 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 the following soft-float comparison routines: 
// 
//   __eqtf2   __getf2   __unordtf2 
//   __letf2   __gttf2 
//   __lttf2 
//   __netf2 
// 
// The semantics of the routines grouped in each column are identical, so there 
// is a single implementation for each, and wrappers to provide the other names. 
// 
// The main routines behave as follows: 
// 
//   __letf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                         1 if either a or b is NaN 
// 
//   __getf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                        -1 if either a or b is NaN 
// 
//   __unordtf2(a,b) returns 0 if both a and b are numbers 
//                           1 if either a or b is NaN 
// 
// Note that __letf2( ) and __getf2( ) are identical except in their handling of 
// NaN values. 
// 
//===----------------------------------------------------------------------===// 
 
#define QUAD_PRECISION 
#include "fp_lib.h" 
 
#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT) 
enum LE_RESULT { 
    LE_LESS      = -1, 
    LE_EQUAL     =  0, 
    LE_GREATER   =  1, 
    LE_UNORDERED =  1 
}; 
 
COMPILER_RT_ABI enum LE_RESULT __letf2(fp_t a, fp_t b) { 
 
    const srep_t aInt = toRep(a); 
    const srep_t bInt = toRep(b); 
    const rep_t aAbs = aInt & absMask; 
    const rep_t bAbs = bInt & absMask; 
 
    // If either a or b is NaN, they are unordered. 
    if (aAbs > infRep || bAbs > infRep) return LE_UNORDERED; 
 
    // If a and b are both zeros, they are equal. 
    if ((aAbs | bAbs) == 0) return LE_EQUAL; 
 
    // If at least one of a and b is positive, we get the same result comparing 
    // a and b as signed integers as we would with a floating-point compare. 
    if ((aInt & bInt) >= 0) { 
        if (aInt < bInt) return LE_LESS; 
        else if (aInt == bInt) return LE_EQUAL; 
        else return LE_GREATER; 
    } 
    else { 
        // Otherwise, both are negative, so we need to flip the sense of the 
        // comparison to get the correct result.  (This assumes a twos- or ones- 
        // complement integer representation; if integers are represented in a 
        // sign-magnitude representation, then this flip is incorrect). 
        if (aInt > bInt) return LE_LESS; 
        else if (aInt == bInt) return LE_EQUAL; 
        else return LE_GREATER; 
    } 
} 
 
#if defined(__ELF__) 
// Alias for libgcc compatibility 
FNALIAS(__cmptf2, __letf2); 
#endif 
 
enum GE_RESULT { 
    GE_LESS      = -1, 
    GE_EQUAL     =  0, 
    GE_GREATER   =  1, 
    GE_UNORDERED = -1   // Note: different from LE_UNORDERED 
}; 
 
COMPILER_RT_ABI enum GE_RESULT __getf2(fp_t a, fp_t b) { 
 
    const srep_t aInt = toRep(a); 
    const srep_t bInt = toRep(b); 
    const rep_t aAbs = aInt & absMask; 
    const rep_t bAbs = bInt & absMask; 
 
    if (aAbs > infRep || bAbs > infRep) return GE_UNORDERED; 
    if ((aAbs | bAbs) == 0) return GE_EQUAL; 
    if ((aInt & bInt) >= 0) { 
        if (aInt < bInt) return GE_LESS; 
        else if (aInt == bInt) return GE_EQUAL; 
        else return GE_GREATER; 
    } else { 
        if (aInt > bInt) return GE_LESS; 
        else if (aInt == bInt) return GE_EQUAL; 
        else return GE_GREATER; 
    } 
} 
 
COMPILER_RT_ABI int __unordtf2(fp_t a, fp_t b) { 
    const rep_t aAbs = toRep(a) & absMask; 
    const rep_t bAbs = toRep(b) & absMask; 
    return aAbs > infRep || bAbs > infRep; 
} 
 
// The following are alternative names for the preceding routines. 
 
COMPILER_RT_ABI enum LE_RESULT __eqtf2(fp_t a, fp_t b) { 
    return __letf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT __lttf2(fp_t a, fp_t b) { 
    return __letf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT __netf2(fp_t a, fp_t b) { 
    return __letf2(a, b); 
} 
 
COMPILER_RT_ABI enum GE_RESULT __gttf2(fp_t a, fp_t b) { 
    return __getf2(a, b); 
} 
 
#endif