During investigate the support of early break autovec, we notice
the test full-vec-move1.c will be optimized to 'return 0;' in main
function body. Because somehow the value of V type is compiler
time constant, and then the second loop will be considered as
assert (true).
Thus, the ccp4 pass will eliminate these stmt and just return 0.
typedef int16_t V __attribute__((vector_size (128)));
int main ()
{
V v;
for (int i = 0; i < sizeof (v) / sizeof (v[0]); i++)
(v)[i] = i;
V res = v;
for (int i = 0; i < sizeof (v) / sizeof (v[0]); i++)
assert (res[i] == i); // will be optimized to assert (true)
}
This patch would like to introduce a extern function to use the res[i]
that get rid of the ccp4 optimization.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/autovec/vls-vlmax/full-vec-move1.c:
Introduce extern func use to get rid of ccp4 optimization.
Signed-off-by: Pan Li <pan2.li@intel.com>
/* { dg-additional-options "-std=c99 -O3 -march=rv64gcv_zvl128b -mabi=lp64d -fno-vect-cost-model -mrvv-vector-bits=zvl" } */
#include <stdint-gcc.h>
-#include <assert.h>
/* This would cause us to emit a vl1r.v for VNx4HImode even when
the hardware vector size vl > 64. */
+extern int16_t test_element (int16_t);
+
typedef int16_t V __attribute__((vector_size (128)));
int main ()
V v;
for (int i = 0; i < sizeof (v) / sizeof (v[0]); i++)
(v)[i] = i;
+
V res = v;
for (int i = 0; i < sizeof (v) / sizeof (v[0]); i++)
- assert (res[i] == i);
+ test_element (res[i]);
}
/* { dg-final { scan-assembler-not {vl[1248]r.v} } } */