Hi, everyone! Here's a simple C snippet. I compile it with icc, but the report of vectorization seems weird.
[cpp]#include
#include
#define N (1 << 20)
#define MB (1 << 20)
int main(void) {
int *a, *b, i;
size_t ms = sizeof(int) * N;
a = (int *) malloc(ms);
b = (int *) malloc(ms);
for (i = 0; i < N; ++i)
a = rand();
for (i = 0; i < N; ++i) /* not an inner loop? */
b = a;
free(a);
free(b);
return 0;
}[/cpp]
Here's how I compiled the code.
[plain]wu@mars:~ $ icc --version && icc -O2 -vec-report3 ex.c
icc (ICC) 12.1.3 20120212
Copyright (C) 1985-2012 Intel Corporation. All rights reserved.
ex.c(11): (col. 12) remark: loop was not vectorized: statement cannot be vectorized.
ex.c(12): (col. 3) remark: LOOP WAS VECTORIZED.
ex.c(12): (col. 3) remark: loop was not vectorized: not inner loop.[/plain]
The output about line (12) confused me. Is the loop of line (12) vectorized or not? Why it's detected as 'not inner loop'?
Thank you in advance!
