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#include <stdio.h>
/* Several equivalent forms that should be turned into cmov */
int test1(int x, int y, int a, int b)
{
return x < y ? a : b;
}
int test2(int x, int y, int a, int b)
{
int r;
if (x < y) { r = a; } else { r = b; }
return r;
}
int test3(int x, int y, int a, int b)
{
int r = b;
if (x < y) { r = a; }
return r;
}
int test4(int x, int y, int a, int b)
{
int r = a;
if (x < y) { /*skip*/; } else { r = b; }
return r;
}
/* A more advanced example */
int test5(int x, int y, int a)
{
return x < y ? a + 1 : a - 1;
}
/* Unsafe operations should not be turned into cmov */
int test6(int * p)
{
return p == NULL ? 0 : *p + 10;
}
int test7(int a, int b)
{
return b == 0 ? -1 : a / b;
}
/* Very large operations should not be turned into cmov */
int test8(int a)
{
return a == 0 ? 0 : a*a*a*a - 2*a*a*a + 10*a*a + 42*a - 123;
}
/* Some examples with 64-bit integers */
long long ltest1(int x, int y, long long a, long long b)
{
return x < y ? a + 1 : b >> 2;
}
/* Some examples with floating-point */
double dmax(double x, double y)
{
return x >= y ? x : y;
}
double dabs(double x)
{
return x < 0.0 ? -x : x;
}
float smin(float x, float y)
{
return x <= y ? x : y;
}
float sdoz(float x, float y)
{
return x >= y ? x - y : 0.0f;
}
/* Examples where constant propagation should take place */
int constprop1(int x)
{
int n = 0;
return n ? x : 42;
}
int constprop2(int x)
{
int n = 1;
return n ? x : 42;
}
int constprop3(int x, int y)
{
int n = 0;
return x < n ? y - 1 : y + 1;
}
/* Test harness */
#define TESTI(call) printf(#call " = %d\n", call)
#define TESTL(call) printf(#call " = %lld\n", call)
#define TESTF(call) printf(#call " = %f\n", call)
int main()
{
int i = 1234;
TESTI(test1(0,1,12,34));
TESTI(test1(1,0,45,67));
TESTI(test2(0,1,12,34));
TESTI(test2(1,0,45,67));
TESTI(test3(0,1,12,34));
TESTI(test3(1,0,45,67));
TESTI(test4(0,1,12,34));
TESTI(test4(1,0,45,67));
TESTI(test5(0,1,12));
TESTI(test5(1,0,45));
TESTI(test6(NULL));
TESTI(test6(&i));
TESTI(test7(1,0));
TESTI(test7(-100,4));
TESTI(test8(0));
TESTI(test8(1));
TESTL(ltest1(-1, 0, 123LL, 456LL));
TESTL(ltest1(1, 0, 123LL, 456LL));
TESTF(dmax(0.0, 3.14));
TESTF(dmax(1.0, -2.718));
TESTF(dabs(1.0));
TESTF(dabs(-2.718));
TESTF(smin(0.0, 3.14));
TESTF(smin(1.0, -2.718));
TESTF(sdoz(1.0, 0.5));
TESTF(sdoz(0.0, 3.14));
return 0;
}
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