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/*
** subnormal-boundary.c
**
** Martin Brain
** martin.brain@cs.ox.ac.uk
** 25/07/12
**
** Regression tests for casting and classification around the subnormal boundary.
**
*/
#include <assert.h>
#include <math.h>
float nondet_float(void);
int main (void)
{
#ifdef __GNUC__
float smallestNormalFloat = 0x1.0p-126f;
float largestSubnormalFloat = 0x1.fffffcp-127f;
double v = 0x1.FFFFFFp-127;
float f;
// Check the encodings are correct
assert(fpclassify(largestSubnormalFloat) == FP_SUBNORMAL);
f = nondet_float();
__CPROVER_assume(fpclassify(f) == FP_SUBNORMAL);
assert(f <= largestSubnormalFloat);
assert(fpclassify(smallestNormalFloat) == FP_NORMAL);
f = nondet_float();
__CPROVER_assume(fpclassify(f) == FP_NORMAL);
assert(smallestNormalFloat <= fabs(f));
assert(largestSubnormalFloat < smallestNormalFloat);
// Check the ordering as doubles
assert(((double)largestSubnormalFloat) < ((double)smallestNormalFloat));
assert(((double)largestSubnormalFloat) < v);
assert(v < ((double)smallestNormalFloat));
// Check coercion to float
assert((float)((double)largestSubnormalFloat) == largestSubnormalFloat);
assert((float)((double)smallestNormalFloat) == smallestNormalFloat);
assert(((double)smallestNormalFloat) - v <= v - ((double)largestSubnormalFloat));
assert(((float)v) == smallestNormalFloat);
f = nondet_float();
__CPROVER_assume(fpclassify(f) == FP_SUBNORMAL);
assert( ((float)((double)f)) == f );
#endif
return 0;
}
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