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///////////////////////////////////////////////////////////////////////////////
//
/// \file bcj_test.c
/// \brief Source code of compress_prepared_bcj_*
///
/// This is a simple program that should make the compiler to generate
/// PC-relative branches, jumps, and calls. The compiled files can then
/// be used to test the branch conversion filters. Note that this program
/// itself does nothing useful.
///
/// Compiling: gcc -std=c99 -fPIC bcj_test.c
/// Don't optimize or strip.
//
// This code has been put into the public domain.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
///////////////////////////////////////////////////////////////////////////////
extern int jump(int a, int b);
extern int
call(int a, int b)
{
if (a < b)
a = jump(a, b);
return a;
}
extern int
jump(int a, int b)
{
// The loop generates conditional jump backwards.
while (1) {
if (a < b) {
a *= 2;
a += 3 * b;
break;
} else {
// Put enough code here to prevent JMP SHORT on x86.
a += b;
a /= 2;
b += b % 5;
a -= b / 3;
b = 2 * b + a - 1;
a *= b + a + 1;
b += a - 1;
a += b * 2 - a / 5;
}
}
return a;
}
int
main(int argc, char **argv)
{
int a = call(argc, argc + 1);
return a == 0;
}
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