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//===-- lib/comparedf2.c - Double-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: 
// 
//   __eqdf2   __gedf2   __unorddf2 
//   __ledf2   __gtdf2 
//   __ltdf2 
//   __nedf2 
// 
// 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: 
// 
//   __ledf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                         1 if either a or b is NaN 
// 
//   __gedf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                        -1 if either a or b is NaN 
// 
//   __unorddf2(a,b) returns 0 if both a and b are numbers 
//                           1 if either a or b is NaN 
// 
// Note that __ledf2( ) and __gedf2( ) are identical except in their handling of 
// NaN values. 
// 
//===----------------------------------------------------------------------===// 
 
#define DOUBLE_PRECISION 
#include "fp_lib.h" 
 
enum LE_RESULT { 
    LE_LESS      = -1, 
    LE_EQUAL     =  0, 
    LE_GREATER   =  1, 
    LE_UNORDERED =  1 
}; 
 
COMPILER_RT_ABI enum LE_RESULT 
__ledf2(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; 
    } 
     
    // 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). 
    else { 
        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(__cmpdf2, __ledf2); 
#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 
__gedf2(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; 
    } 
} 
 
ARM_EABI_FNALIAS(dcmpun, unorddf2) 
 
COMPILER_RT_ABI int 
__unorddf2(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 
__eqdf2(fp_t a, fp_t b) { 
    return __ledf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT 
__ltdf2(fp_t a, fp_t b) { 
    return __ledf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT 
__nedf2(fp_t a, fp_t b) { 
    return __ledf2(a, b); 
} 
 
COMPILER_RT_ABI enum GE_RESULT 
__gtdf2(fp_t a, fp_t b) { 
    return __gedf2(a, b); 
}