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#pragma once
#define MAX_JUMP_PATCH_SIZE 14
#include "dis.h"
static inline int jump_patch_size(uint_tptr pc, uint_tptr dpc,
UNUSED struct arch_dis_ctx arch,
bool force) {
uint_tptr diff = dpc - (pc + 5);
/* fits in 32? */
if (diff == (uint_tptr) (int32_t) diff)
return 5;
else
return force ? (2+4+8) : -1;
}
static inline void make_jmp_or_call(void **codep, uint_tptr pc, uint_tptr dpc,
bool call) {
uint_tptr diff = dpc - (pc + 5);
void *code = *codep;
if (diff == (uint_tptr) (int32_t) diff) {
op8(&code, call ? 0xe8 : 0xe9);
op32(&code, diff);
} else {
/* jmpq *(%rip) */
op8(&code, 0xff);
op8(&code, call ? 0x15 : 0x25);
op32(&code, 0);
op64(&code, dpc);
}
*codep = code;
}
static inline void make_jump_patch(void **codep, uint_tptr pc, uint_tptr dpc,
UNUSED struct arch_dis_ctx arch) {
make_jmp_or_call(codep, pc, dpc, false);
}
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