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| // RUN: %clang_builtins %s %librt -o %t && %run %t
//===-- compiler_rt_logb_test.c - Test __compiler_rt_logb -----------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file checks __compiler_rt_logb from the compiler_rt library for
// conformance against libm.
//
//===----------------------------------------------------------------------===//
#define DOUBLE_PRECISION
#include <math.h>
#include <stdio.h>
#include "fp_lib.h"
int test__compiler_rt_logb(fp_t x) {
fp_t crt_value = __compiler_rt_logb(x);
fp_t libm_value = logb(x);
// Compare actual rep, e.g. to avoid NaN != the same NaN
if (toRep(crt_value) != toRep(libm_value)) {
printf("error: in __compiler_rt_logb(%a [%lX]) = %a [%lX] != %a [%lX]\n",
x, toRep(x), crt_value, toRep(crt_value), libm_value,
toRep(libm_value));
return 1;
}
return 0;
}
double cases[] = {
1.e-6, -1.e-6, NAN, -NAN, INFINITY, -INFINITY, -1,
-0.0, 0.0, 1, -2, 2, -0.5, 0.5,
};
#ifndef __GLIBC_PREREQ
#define __GLIBC_PREREQ(x, y) 0
#endif
int main() {
// Do not the run the compiler-rt logb test case if using GLIBC version
// < 2.23. Older versions might not compute to the same value as the
// compiler-rt value.
#if __GLIBC_PREREQ(2, 23)
const unsigned N = sizeof(cases) / sizeof(cases[0]);
unsigned i;
for (i = 0; i < N; ++i) {
if (test__compiler_rt_logb(cases[i])) return 1;
}
// Test a moving 1 bit, especially to handle denormal values.
// Test the negation as well.
rep_t x = signBit;
while (x) {
if (test__compiler_rt_logb(fromRep(x))) return 1;
if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;
x >>= 1;
}
// Also try a couple moving ones
x = signBit | (signBit >> 1) | (signBit >> 2);
while (x) {
if (test__compiler_rt_logb(fromRep(x))) return 1;
if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;
x >>= 1;
}
#else
printf("skipped\n");
#endif
return 0;
}
|