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// SPDX-License-Identifier: GPL-2.0
/* callx through pointers to functions in .rodata, loaded by light skeleton */
#include <stdbool.h>
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
/* set by user space before the programs are loaded, it's in .rodata too */
const volatile int bias = 1;
int op_idx;
#ifdef __clang__
const volatile bool skip = false;
typedef int (*op_fn)(int);
static __noinline int add_bias(int x)
{
return x + bias;
}
static __noinline int mul3(int x)
{
return x * 3;
}
/* volatile, so that the compiler doesn't replace the table with direct calls */
static op_fn const volatile ops[] = { add_bias, mul3 };
SEC("socket")
int select_op(void *ctx)
{
unsigned int i = op_idx;
if (i >= sizeof(ops) / sizeof(ops[0]))
return -1;
return ops[i](10);
}
/* functions have other offsets in this program */
SEC("socket")
int both_ops(void *ctx)
{
return ops[1](ops[0](4));
}
#else
/* gcc doesn't support indirect calls */
const volatile bool skip = true;
SEC("socket")
int select_op(void *ctx)
{
return 0;
}
SEC("socket")
int both_ops(void *ctx)
{
return 0;
}
#endif
/* no callx here */
SEC("socket")
int read_bias(void *ctx)
{
return bias;
}
char _license[] SEC("license") = "GPL";
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