instrlist_t*
instrlist_clone(dcontext_t *dcontext, instrlist_t *old)
{
instr_t *inst, *copy;
instrlist_t *newlist = instrlist_create(dcontext);
inst = instrlist_first(old);
while (inst != NULL) {
copy = instr_clone(dcontext, inst);
/* to copy instr targets we temporarily clobber note field */
instr_set_note(inst, (void *)copy);
instrlist_append(newlist, copy);
inst = instr_get_next(inst);
}
/* Fix up instr src if it is an instr and restore note field */
/* Note: we do not allows instruction update code cache,
* which is very dangerous.
* So we do not support instr as dst opnd and won't fix up here if any.
*/
for (inst = instrlist_first(old), copy = instrlist_first(newlist);
inst != NULL && copy != NULL;
inst = instr_get_next(inst), copy = instr_get_next(copy)) {
int i;
for (i = 0; i < inst->num_srcs; i++) {
instr_t *tgt;
opnd_t op = instr_get_src(copy, i);
if (!opnd_is_instr(op))
continue;
CLIENT_ASSERT(opnd_get_instr(op) != NULL,
"instrlist_clone: NULL instr operand");
tgt = (instr_t *) instr_get_note(opnd_get_instr(op));
CLIENT_ASSERT(tgt != NULL,
"instrlist_clone: operand instr not in instrlist");
if (opnd_is_far_instr(op)) {
instr_set_src(copy, i,
opnd_create_far_instr
(opnd_get_segment_selector(op), tgt));
} else
instr_set_src(copy, i,
opnd_create_instr(tgt));
}
}
for (inst = instrlist_first(old), copy = instrlist_first(newlist);
inst != NULL && copy != NULL;
inst = instr_get_next(inst), copy = instr_get_next(copy)) {
/* restore note field */
instr_set_note(inst, instr_get_note(copy));
}
#ifdef CLIENT_INTERFACE
newlist->fall_through_bb = old->fall_through_bb;
#endif
return newlist;
}
void
cfi_call_instrumentation_snapahot(void *dcontext, instrlist_t *ilist, instr_t *where, void *callee)
{
uint dstack_offs = 0, pad = 0;
unsigned int eflags_offs;
CFI_ASSERT(dcontext != NULL, "cfi_call_instrumentation_snapahot: dcontext cannot be NULL");
instr_t *next_snapshot = INSTR_CREATE_label(dcontext);
PRE(ilist, where, INSTR_CREATE_pushf(dcontext));
dstack_offs += XSP_SZ;
eflags_offs = dstack_offs;
PRE(ilist, where, INSTR_CREATE_push(dcontext, opnd_create_reg(DR_REG_RDI)));
dstack_offs += XSP_SZ;
PRE(ilist, where, INSTR_CREATE_mov_imm(dcontext, opnd_create_reg(DR_REG_RDI), OPND_CREATE_INT64(&flag_memory_snapshot)));
PRE(ilist, where, INSTR_CREATE_mov_ld(dcontext, opnd_create_reg(DR_REG_RDI), opnd_create_base_disp(DR_REG_RDI, DR_REG_NULL, 0, 0, OPSZ_PTR)));
PRE(ilist, where, INSTR_CREATE_cmp(dcontext, opnd_create_reg(DR_REG_RDI), OPND_CREATE_INT8(0x0)));
PRE(ilist, where, INSTR_CREATE_jcc(dcontext, OP_je, opnd_create_instr(next_snapshot)));
PRE(ilist, where, INSTR_CREATE_push(dcontext,
opnd_create_base_disp(DR_REG_RSP, DR_REG_NULL, 0,
dstack_offs - eflags_offs, OPSZ_STACK)));
PRE(ilist, where, INSTR_CREATE_and(dcontext,
opnd_create_base_disp(DR_REG_RSP, DR_REG_NULL, 0, 0,
OPSZ_STACK),
OPND_CREATE_INT32(~(EFLAGS_NON_SYSTEM | EFLAGS_IF))));
PRE(ilist, where, INSTR_CREATE_popf(dcontext));
instrlist_set_our_mangling(ilist, true);
cfi_insert_meta_native_call_vargs(dcontext, ilist, where, true/*clean*/, callee);
instrlist_set_our_mangling(ilist, false);
cfi_insert_native_call(dcontext, ilist, where, callee /*, opnd_create_reg(DR_REG_RAX)*/);
PRE(ilist, where, next_snapshot);
PRE(ilist, where, INSTR_CREATE_pop(dcontext, opnd_create_reg(DR_REG_RDI)));
PRE(ilist, where, INSTR_CREATE_popf(dcontext));
/* dstack_offs = cfi_prepare_for_native_call(dcontext, ilist, where);
instrlist_set_our_mangling(ilist, true);
cfi_insert_meta_native_call_vargs(dcontext, ilist, where, true*//*clean*//*, callee);
instrlist_set_our_mangling(ilist, false);
cfi_cleanup_after_native_call(dcontext, ilist, where);*/
}
static dr_emit_flags_t
event_bb(void *dc, void *tag, instrlist_t *bb, bool for_trace, bool translating)
{
instr_t *where = instrlist_first(bb);
instr_t *ret_label = INSTR_CREATE_label(dc);
dr_save_reg(dc, bb, where, DR_REG_XAX, SPILL_SLOT_1);
PRE(bb, where, INSTR_CREATE_mov_imm(dc, opnd_create_reg(DR_REG_XAX),
opnd_create_instr(ret_label)));
PRE(bb, where, INSTR_CREATE_jmp(dc, opnd_create_pc(slowpath)));
PRE(bb, where, ret_label);
dr_restore_reg(dc, bb, where, DR_REG_XAX, SPILL_SLOT_1);
return DR_EMIT_DEFAULT;
}
static dr_emit_flags_t
bb_event(void *drcontext, void *tag, instrlist_t *bb, bool for_trace, bool translating)
{
instr_t *instr, *next_instr;
for (instr = instrlist_first(bb); instr != NULL; instr = next_instr) {
next_instr = instr_get_next(instr);
if (instr_is_cbr(instr)) {
/* Conditional branch. We can determine the target and
* fallthrough addresses here, but we want to note the
* edge if and when it actually executes at runtime.
* Instead of using dr_insert_cbr_instrumentation(), we'll
* insert separate instrumentation for the taken and not
* taken cases and remove the instrumentation for an edge
* after it executes.
*/
cbr_state_t state;
bool insert_taken, insert_not_taken;
app_pc src = instr_get_app_pc(instr);
/* First look up the state of this branch so we
* know what instrumentation to insert, if any.
*/
elem_t *elem = lookup(table, src);
if (elem == NULL) {
state = CBR_NEITHER;
insert(table, src, CBR_NEITHER);
}
else {
state = elem->state;
}
insert_taken = (state & CBR_TAKEN) == 0;
insert_not_taken = (state & CBR_NOT_TAKEN) == 0;
if (insert_taken || insert_not_taken) {
app_pc fall = (app_pc)decode_next_pc(drcontext, (byte *)src);
app_pc targ = instr_get_branch_target_pc(instr);
/* Redirect the existing cbr to jump to a callout for
* the 'taken' case. We'll insert a 'not-taken'
* callout at the fallthrough address.
*/
instr_t *label = INSTR_CREATE_label(drcontext);
/* should be meta, and meta-instrs shouldn't have translations */
instr_set_meta_no_translation(instr);
/* it may not reach (in particular for x64) w/ our added clean call */
if (instr_is_cti_short(instr)) {
/* if jecxz/loop we want to set the target of the long-taken
* so set instr to the return value
*/
instr = instr_convert_short_meta_jmp_to_long(drcontext, bb, instr);
}
instr_set_target(instr, opnd_create_instr(label));
if (insert_not_taken) {
/* Callout for the not-taken case. Insert after
* the cbr (i.e., 3rd argument is NULL).
*/
dr_insert_clean_call(drcontext, bb, NULL,
(void*)at_not_taken,
false /* don't save fp state */,
2 /* 2 args for at_not_taken */,
OPND_CREATE_INTPTR(src),
OPND_CREATE_INTPTR(fall));
}
/* After the callout, jump to the original fallthrough
* address. Note that this is an exit cti, and should
* not be a meta-instruction. Therefore, we use
* preinsert instead of meta_preinsert, and we must
* set the translation field. On Windows, this jump
* and the final jump below never execute since the
* at_taken and at_not_taken callouts redirect
* execution and never return. However, since the API
* expects clients to produced well-formed code, we
* insert explicit exits from the block for Windows as
* well as Linux.
*/
instrlist_preinsert(bb, NULL,
INSTR_XL8(INSTR_CREATE_jmp
(drcontext, opnd_create_pc(fall)), fall));
/* label goes before the 'taken' callout */
MINSERT(bb, NULL, label);
if (insert_taken) {
/* Callout for the taken case */
dr_insert_clean_call(drcontext, bb, NULL,
(void*)at_taken,
false /* don't save fp state */,
2 /* 2 args for at_taken */,
OPND_CREATE_INTPTR(src),
OPND_CREATE_INTPTR(targ));
}
/* After the callout, jump to the original target
* block (this should not be a meta-instruction).
*/
instrlist_preinsert(bb, NULL,
INSTR_XL8(INSTR_CREATE_jmp
(drcontext, opnd_create_pc(targ)), targ));
}
}
}
/* since our added instrumentation is not constant, we ask to store
* translations now
*/
return DR_EMIT_STORE_TRANSLATIONS;
}
static void dynamic_info_instrumentation(void *drcontext, instrlist_t *ilist, instr_t *where,
instr_t * static_info)
{
/*
issues that may arise
1. pc and eflags is uint but in 64 bit mode 8 byte transfers are done -> so far no problem (need to see this)
need to see whether there is a better way
2. double check all the printing
*/
/*
this function does the acutal instrumentation
arguments -
we get a filled pointer here about the operand types for a given instruction (srcs and dests)
1) increment the pointer to the instr_trace buffers
2) add this pointer to instr_trace_t wrapper
3) check whether any of the srcs and dests have memory operations; if so add a lea instruction and get the dynamic address
Add this address to instr_trace_t structure
4) if the buffer is full call a function to dump it to the file and restore the head ptr of the buffer
(lean function is used utilizing a code cache to limit code bloat needed for a clean call before every instruction.)
*/
instr_t *instr, *call, *restore, *first, *second;
opnd_t ref, opnd1, opnd2;
reg_id_t reg1 = DR_REG_XBX; /* We can optimize it by picking dead reg */
reg_id_t reg2 = DR_REG_XCX; /* reg2 must be ECX or RCX for jecxz */
reg_id_t reg3 = DR_REG_XAX;
per_thread_t *data;
uint pc;
uint i;
module_data_t * module_data;
if (client_arg->instrace_mode == DISASSEMBLY_TRACE){
dr_insert_clean_call(drcontext, ilist, where, clean_call_disassembly_trace, false, 0);
return;
}
data = drmgr_get_tls_field(drcontext, tls_index);
/* Steal the register for memory reference address *
* We can optimize away the unnecessary register save and restore
* by analyzing the code and finding the register is dead.
*/
dr_save_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_save_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
dr_save_reg(drcontext, ilist, where, reg3, SPILL_SLOT_4);
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg2);
/* Load data->buf_ptr into reg2 */
opnd1 = opnd_create_reg(reg2);
opnd2 = OPND_CREATE_MEMPTR(reg2, offsetof(per_thread_t, buf_ptr));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* buf_ptr->static_info_instr = static_info; */
/* Move static_info to static_info_instr field of buf (which is a instr_trace_t *) */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(instr_trace_t, static_info_instr));
instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t)static_info, opnd1, ilist, where, &first, &second);
/* buf_ptr->num_mem = 0; */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(instr_trace_t, num_mem));
instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t)0, opnd1, ilist, where, &first, &second);
for (i = 0; i<instr_num_dsts(where); i++){
if (opnd_is_memory_reference(instr_get_dst(where, i))){
ref = instr_get_dst(where, i);
DR_ASSERT(opnd_is_null(ref) == false);
dr_restore_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_restore_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
#ifdef DEBUG_MEM_REGS
dr_insert_clean_call(drcontext, ilist, where, clean_call_disassembly_trace, false, 0);
dr_insert_clean_call(drcontext, ilist, where, clean_call_print_regvalues, false, 0);
#endif
drutil_insert_get_mem_addr(drcontext, ilist, where, ref, reg1, reg2);
#ifdef DEBUG_MEM_REGS
dr_insert_clean_call(drcontext, ilist, where, clean_call_print_regvalues, false, 0);
#endif
#ifdef DEBUG_MEM_STATS
dr_insert_clean_call(drcontext, ilist, where, clean_call_disassembly_trace, false, 0);
dr_insert_clean_call(drcontext, ilist, where, clean_call_mem_stats, false, 1, opnd_create_reg(reg1));
#endif
dr_insert_clean_call(drcontext, ilist, where, clean_call_populate_mem, false, 3, opnd_create_reg(reg1), OPND_CREATE_INT32(i), OPND_CREATE_INT32(DST_TYPE));
}
}
for (i = 0; i<instr_num_srcs(where); i++){
if (opnd_is_memory_reference(instr_get_src(where, i))){
ref = instr_get_src(where, i);
DR_ASSERT(opnd_is_null(ref) == false);
dr_restore_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_restore_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
#ifdef DEBUG_MEM_REGS
dr_insert_clean_call(drcontext, ilist, where, clean_call_disassembly_trace, false, 0);
dr_insert_clean_call(drcontext, ilist, where, clean_call_print_regvalues, false, 0);
#endif
drutil_insert_get_mem_addr(drcontext, ilist, where, ref, reg1, reg2);
#ifdef DEBUG_MEM_REGS
dr_insert_clean_call(drcontext, ilist, where, clean_call_print_regvalues, false, 0);
#endif
#ifdef DEBUG_MEM_STATS
dr_insert_clean_call(drcontext, ilist, where, clean_call_disassembly_trace, false, 0);
dr_insert_clean_call(drcontext, ilist, where, clean_call_mem_stats, false, 1, opnd_create_reg(reg1));
#endif
dr_insert_clean_call(drcontext, ilist, where, clean_call_populate_mem, false, 3, opnd_create_reg(reg1), OPND_CREATE_INT32(i), OPND_CREATE_INT32(SRC_TYPE));
}
}
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg2);
/* Load data->buf_ptr into reg2 */
opnd1 = opnd_create_reg(reg2);
opnd2 = OPND_CREATE_MEMPTR(reg2, offsetof(per_thread_t, buf_ptr));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* arithmetic flags are saved here for buf_ptr->eflags filling */
dr_save_arith_flags_to_xax(drcontext, ilist, where);
/* load the eflags */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(instr_trace_t, eflags));
opnd2 = opnd_create_reg(reg3);
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* load the app_pc */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(instr_trace_t, pc));
module_data = dr_lookup_module(instr_get_app_pc(where));
//dynamically generated code - module information not available - then just store 0 at the pc slot of the instr_trace data
if (module_data != NULL){
pc = instr_get_app_pc(where) - module_data->start;
dr_free_module_data(module_data);
}
else{
pc = 0;
}
instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t)pc, opnd1, ilist, where, &first, &second);
/* buf_ptr++; */
/* Increment reg value by pointer size using lea instr */
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg2, DR_REG_NULL, 0,
sizeof(instr_trace_t),
OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Update the data->buf_ptr */
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg1);
opnd1 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_ptr));
opnd2 = opnd_create_reg(reg2);
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* we use lea + jecxz trick for better performance
* lea and jecxz won't disturb the eflags, so we won't insert
* code to save and restore application's eflags.
*/
/* lea [reg2 - buf_end] => reg2 */
opnd1 = opnd_create_reg(reg1);
opnd2 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_end));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg1, reg2, 1, 0, OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jecxz call */
call = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(call);
instr = INSTR_CREATE_jecxz(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* jump restore to skip clean call */
restore = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(restore);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* clean call */
/* We jump to lean procedure which performs full context switch and
* clean call invocation. This is to reduce the code cache size.
*/
instrlist_meta_preinsert(ilist, where, call);
/* mov restore DR_REG_XCX */
opnd1 = opnd_create_reg(reg2);
/* this is the return address for jumping back from lean procedure */
opnd2 = opnd_create_instr(restore);
/* We could use instrlist_insert_mov_instr_addr(), but with a register
* destination we know we can use a 64-bit immediate.
*/
instr = INSTR_CREATE_mov_imm(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jmp code_cache */
opnd1 = opnd_create_pc(code_cache);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* restore %reg */
instrlist_meta_preinsert(ilist, where, restore);
//dr_restore_arith_flags_from_xax(drcontext, ilist, where);
dr_restore_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_restore_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
dr_restore_reg(drcontext, ilist, where, reg3, SPILL_SLOT_4);
//instrlist_disassemble(drcontext, instr_get_app_pc(instrlist_first(ilist)), ilist, logfile);
}
dr_emit_flags_t
bb_event(void *drcontext, void *tag, instrlist_t *bb, bool for_trace, bool translating)
{
instr_t *instr, *next_instr;
app_pc bb_addr = dr_fragment_app_pc(tag);
if (bb_addr == start_pc) {
instrument = true;
} else if (bb_addr == stop_pc) {
instrument = false;
}
if (!instrument) {
return DR_EMIT_DEFAULT;
}
for (instr = instrlist_first(bb); instr != NULL; instr = next_instr) {
next_instr = instr_get_next(instr);
/*
* Conditional branch. We can determine the target and
* fallthrough addresses here, but we need to instrument if we
* want to record the edge only if it actually executes at
* runtime. Instead of using dr_insert_cbr_instrumentation,
* we'll insert separate instrumentation for the taken and not
* taken cases and remove it separately after we see each
* case.
*/
if (instr_is_cbr(instr)) {
app_pc src = instr_get_app_pc(instr);
cbr_state_t state;
bool insert_taken, insert_not_taken;
/* First look up the state of this branch so we
* know what instrumentation to insert, if any.
*/
elem_t *elem = lookup(table, src);
if (elem == NULL) {
state = CBR_NONE;
insert(table, src, CBR_NONE);
} else {
state = elem->state;
}
insert_taken = (state & CBR_TAKEN) == 0;
insert_not_taken = (state & CBR_NOT_TAKEN) == 0;
if (insert_taken || insert_not_taken) {
app_pc fall = (app_pc)decode_next_pc(drcontext, (byte *)src);
app_pc targ = instr_get_branch_target_pc(instr);
/*
* Redirect the cbr to jump to the 'taken' callout.
* We'll insert a 'not-taken' callout at fallthrough
* address.
*/
instr_t *label = INSTR_CREATE_label(drcontext);
instr_set_meta(instr);
instr_set_translation(instr, NULL);
/* If this is a short cti, make sure it can reach its new target */
if (instr_is_cti_short(instr)) {
/* if jecxz/loop we want to set the target of the long-taken
* so set instr to the return value
*/
instr = instr_convert_short_meta_jmp_to_long(drcontext, bb, instr);
}
instr_set_target(instr, opnd_create_instr(label));
if (insert_not_taken) {
/*
* Callout for the not-taken case
*/
dr_insert_clean_call(drcontext, bb, NULL, (void *)at_not_taken,
false /* don't save fp state */,
2 /* 2 args for at_not_taken */,
OPND_CREATE_INTPTR((ptr_uint_t)src),
OPND_CREATE_INTPTR((ptr_uint_t)fall));
}
/*
* Jump to the original fall-through address.
* (This should not be a meta-instruction).
*/
instrlist_preinsert(
bb, NULL,
INSTR_XL8(INSTR_CREATE_jmp(drcontext, opnd_create_pc(fall)), fall));
/* label goes before the 'taken' callout */
MINSERT(bb, NULL, label);
if (insert_taken) {
/*
* Callout for the taken case
*/
dr_insert_clean_call(drcontext, bb, NULL, (void *)at_taken,
false /* don't save fp state */,
2 /* 2 args for at_taken */,
OPND_CREATE_INTPTR((ptr_uint_t)src),
OPND_CREATE_INTPTR((ptr_uint_t)targ));
}
/*
* Jump to the original target block (this should
* not be a meta-instruction).
*/
instrlist_preinsert(
bb, NULL,
INSTR_XL8(INSTR_CREATE_jmp(drcontext, opnd_create_pc(targ)), targ));
}
}
}
/* since our added instrumentation is not constant, we ask to store
* translations now
*/
return DR_EMIT_STORE_TRANSLATIONS;
}
void
test_dr_insert_it_instrs_cbr(void *dcontext)
{
instrlist_t *ilist = instrlist_create(dcontext);
instr_t *where = INSTR_CREATE_label(dcontext);
instr_t *instr_it1, *instr_it2, *instr_it3;
byte buffer[4096];
instrlist_append(ilist, where);
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_jump
(dcontext,
opnd_create_instr(where)));
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_jump
(dcontext,
opnd_create_instr(where)));
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_move
(dcontext,
opnd_create_reg(DR_REG_R1),
opnd_create_reg(DR_REG_R2)));
instrlist_preinsert(ilist, where, XINST_CREATE_jump
(dcontext,
opnd_create_instr(where)));
/* set them all to be predicated and reinstate it instrs */
for (where = instrlist_first(ilist); where; where = instr_get_next(where)) {
bool ok = instr_set_isa_mode(where, DR_ISA_ARM_THUMB);
DR_ASSERT(ok);
instr_set_predicate(where, DR_PRED_LS);
}
dr_insert_it_instrs(dcontext, ilist);
/* Make sure it was encoded properly, noting that the branches
* should *not* be in any IT-block.
* it
* mov.ls r1, r2
* b.ls @0x47366864
* itt
* mov.ls r1, r2
* mov.ls r1, r2
* b.ls @0x47366864
* ittt
* mov.ls r1, r2
* mov.ls r1, r2
* mov.ls r1, r2
* b.ls @0x47366864
*/
instr_it1 = instrlist_first(ilist);
instr_it2 = instr_get_next(instr_get_next(instr_get_next(instr_it1)));
instr_it3 = instr_get_next(instr_get_next(instr_get_next(instr_get_next(instr_it2))));
DR_ASSERT(instr_get_opcode(instr_it1) == OP_it);
DR_ASSERT(instr_it_block_get_count(instr_it1) == 1);
DR_ASSERT(instr_get_opcode(instr_it2) == OP_it);
DR_ASSERT(instr_it_block_get_count(instr_it2) == 2);
DR_ASSERT(instr_get_opcode(instr_it3) == OP_it);
DR_ASSERT(instr_it_block_get_count(instr_it3) == 3);
instrlist_encode(dcontext, ilist, buffer, true);
}
void
watchpoint_indirect_call_event(dcontext_t *drcontext, instrlist_t *ilist, instr_t *instr,
instr_t *next_instr, bool mangle_calls, uint flags)
{
opnd_t instr_opnd;
reg_id_t base_reg;
unsigned long used_registers = 0;
app_pc pc;
struct memory_operand_modifier ops = {0};
instr_t *begin_instrumenting = INSTR_CREATE_label(drcontext);
instr_t *done_instrumenting = INSTR_CREATE_label(drcontext);
instr_t *nop = INSTR_CREATE_nop(drcontext);
instr_t *emulated;
memset(&ops, 0, sizeof(struct memory_operand_modifier));
if(instr_reads_memory(instr)) {
instr_opnd = instr_get_src(instr, 0);
if (opnd_is_rel_addr(instr_opnd) || opnd_is_abs_addr(instr_opnd)) {
}else if (opnd_is_base_disp(instr_opnd)) {
for_each_src_operand(instr, &ops, (opnd_callback_t *) memory_src_operand_finder);
// base_reg = opnd_get_reg(instr_opnd);
switch(ops.found_operand.value.base_disp.base_reg) {
case DR_REG_RSP: case DR_REG_ESP: case DR_REG_SP:
case DR_REG_RBP: case DR_REG_EBP: case DR_REG_BP:
return;
default:
break;
}
collect_regs(&used_registers, instr, instr_num_srcs, instr_get_src );
collect_regs(&used_registers, instr, instr_num_dsts, instr_get_dst );
reg_id_t reg_watched_addr = get_next_free_reg(&used_registers);
opnd_t opnd_watched_addr = opnd_create_reg(reg_watched_addr);
reg_id_t reg_unwatched_addr = get_next_free_reg(&used_registers);
opnd_t opnd_unwatched_addr = opnd_create_reg(reg_unwatched_addr);
PRE(ilist, instr, begin_instrumenting);
PRE(ilist, instr, INSTR_CREATE_push(drcontext, opnd_watched_addr));
PRE(ilist, instr, INSTR_CREATE_push(drcontext, opnd_unwatched_addr));
PRE(ilist, instr, INSTR_CREATE_pushf(drcontext));
PRE(ilist, instr, INSTR_CREATE_lea(drcontext, opnd_watched_addr, opnd_create_base_disp(opnd_get_base(ops.found_operand),
opnd_get_index(ops.found_operand), opnd_get_scale(ops.found_operand),
opnd_get_disp(ops.found_operand), OPSZ_lea)));
PRE(ilist, instr, INSTR_CREATE_mov_imm(drcontext, opnd_unwatched_addr,
OPND_CREATE_INT64(WATCHPOINT_INDEX_MASK)));
PRE(ilist, instr, INSTR_CREATE_or(drcontext, opnd_unwatched_addr, opnd_watched_addr));
emulated = instr_clone(drcontext, instr);
emulated->translation = 0;
ops.replacement_operand = opnd_create_base_disp(
reg_unwatched_addr, DR_REG_NULL,1, 0 , ops.found_operand.size);
for_each_operand(emulated, &ops, (opnd_callback_t *) memory_operand_replacer);
PRE(ilist, instr, INSTR_CREATE_popf(drcontext));
PRE(ilist, instr, emulated);
PRE(ilist, instr, INSTR_CREATE_pop(drcontext, opnd_unwatched_addr));
PRE(ilist, instr, INSTR_CREATE_pop(drcontext, opnd_watched_addr));
PRE(ilist, instr, INSTR_CREATE_jmp_short(drcontext,
opnd_create_instr(done_instrumenting)));
pc = instr->translation;
instr->translation = 0; // hack!
instr_being_modified(instr, false);
instr_set_ok_to_mangle(instr, false);
if(NULL != pc){
nop->translation = pc + instr->length;
}
POST(ilist, instr, nop);
POST(ilist, instr, done_instrumenting);
}
}
}
/* instrument_instr is called whenever a memory reference is identified.
* It inserts code before the memory reference to to fill the memory buffer
* and jump to our own code cache to call the clean_call when the buffer is full.
*/
static void
instrument_instr(void *drcontext, instrlist_t *ilist, instr_t *where)
{
instr_t *instr, *call, *restore;
opnd_t opnd1, opnd2;
reg_id_t reg1, reg2;
drvector_t allowed;
per_thread_t *data;
app_pc pc;
data = drmgr_get_tls_field(drcontext, tls_index);
/* Steal two scratch registers.
* reg2 must be ECX or RCX for jecxz.
*/
drreg_init_and_fill_vector(&allowed, false);
drreg_set_vector_entry(&allowed, DR_REG_XCX, true);
if (drreg_reserve_register(drcontext, ilist, where, &allowed, ®2) !=
DRREG_SUCCESS ||
drreg_reserve_register(drcontext, ilist, where, NULL, ®1) != DRREG_SUCCESS) {
DR_ASSERT(false); /* cannot recover */
drvector_delete(&allowed);
return;
}
drvector_delete(&allowed);
/* The following assembly performs the following instructions
* buf_ptr->pc = pc;
* buf_ptr->opcode = opcode;
* buf_ptr++;
* if (buf_ptr >= buf_end_ptr)
* clean_call();
*/
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg2);
/* Load data->buf_ptr into reg2 */
opnd1 = opnd_create_reg(reg2);
opnd2 = OPND_CREATE_MEMPTR(reg2, offsetof(per_thread_t, buf_ptr));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Store pc */
pc = instr_get_app_pc(where);
/* For 64-bit, we can't use a 64-bit immediate so we split pc into two halves.
* We could alternatively load it into reg1 and then store reg1.
* We use a convenience routine that does the two-step store for us.
*/
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(ins_ref_t, pc));
instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t) pc, opnd1,
ilist, where, NULL, NULL);
/* Store opcode */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(ins_ref_t, opcode));
opnd2 = OPND_CREATE_INT32(instr_get_opcode(where));
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Increment reg value by pointer size using lea instr */
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg2, DR_REG_NULL, 0, sizeof(ins_ref_t), OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Update the data->buf_ptr */
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg1);
opnd1 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_ptr));
opnd2 = opnd_create_reg(reg2);
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* We use the lea + jecxz trick for better performance.
* lea and jecxz won't disturb the eflags, so we won't need
* code to save and restore the application's eflags.
*/
/* lea [reg2 - buf_end] => reg2 */
opnd1 = opnd_create_reg(reg1);
opnd2 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_end));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg1, reg2, 1, 0, OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jecxz call */
call = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(call);
instr = INSTR_CREATE_jecxz(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* jump restore to skip clean call */
restore = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(restore);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* clean call */
/* We jump to our generated lean procedure which performs a full context
* switch and clean call invocation. This is to reduce the code cache size.
*/
instrlist_meta_preinsert(ilist, where, call);
/* mov restore DR_REG_XCX */
opnd1 = opnd_create_reg(reg2);
/* This is the return address for jumping back from the lean procedure. */
opnd2 = opnd_create_instr(restore);
/* We could use instrlist_insert_mov_instr_addr(), but with a register
* destination we know we can use a 64-bit immediate.
*/
instr = INSTR_CREATE_mov_imm(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jmp code_cache */
opnd1 = opnd_create_pc(code_cache);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* Restore scratch registers */
instrlist_meta_preinsert(ilist, where, restore);
if (drreg_unreserve_register(drcontext, ilist, where, reg1) != DRREG_SUCCESS ||
drreg_unreserve_register(drcontext, ilist, where, reg2) != DRREG_SUCCESS)
DR_ASSERT(false);
}
/*
* instrument_mem is called whenever a memory reference is identified.
* It inserts code before the memory reference to to fill the memory buffer
* and jump to our own code cache to call the clean_call when the buffer is full.
*/
static void
instrument_mem(void *drcontext, instrlist_t *ilist, instr_t *where,
int pos, bool write)
{
instr_t *instr, *call, *restore, *first, *second;
opnd_t ref, opnd1, opnd2;
reg_id_t reg1 = DR_REG_XBX; /* We can optimize it by picking dead reg */
reg_id_t reg2 = DR_REG_XCX; /* reg2 must be ECX or RCX for jecxz */
per_thread_t *data;
app_pc pc;
data = drmgr_get_tls_field(drcontext, tls_index);
/* Steal the register for memory reference address *
* We can optimize away the unnecessary register save and restore
* by analyzing the code and finding the register is dead.
*/
dr_save_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_save_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
if (write)
ref = instr_get_dst(where, pos);
else
ref = instr_get_src(where, pos);
/* use drutil to get mem address */
drutil_insert_get_mem_addr(drcontext, ilist, where, ref, reg1, reg2);
/* The following assembly performs the following instructions
* buf_ptr->write = write;
* buf_ptr->addr = addr;
* buf_ptr->size = size;
* buf_ptr->pc = pc;
* buf_ptr++;
* if (buf_ptr >= buf_end_ptr)
* clean_call();
*/
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg2);
/* Load data->buf_ptr into reg2 */
opnd1 = opnd_create_reg(reg2);
opnd2 = OPND_CREATE_MEMPTR(reg2, offsetof(per_thread_t, buf_ptr));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Move write/read to write field */
opnd1 = OPND_CREATE_MEM32(reg2, offsetof(mem_ref_t, write));
opnd2 = OPND_CREATE_INT32(write);
instr = INSTR_CREATE_mov_imm(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Store address in memory ref */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(mem_ref_t, addr));
opnd2 = opnd_create_reg(reg1);
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Store size in memory ref */
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(mem_ref_t, size));
/* drutil_opnd_mem_size_in_bytes handles OP_enter */
opnd2 = OPND_CREATE_INT32(drutil_opnd_mem_size_in_bytes(ref, where));
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Store pc in memory ref */
pc = instr_get_app_pc(where);
/* For 64-bit, we can't use a 64-bit immediate so we split pc into two halves.
* We could alternatively load it into reg1 and then store reg1.
* We use a convenience routine that does the two-step store for us.
*/
opnd1 = OPND_CREATE_MEMPTR(reg2, offsetof(mem_ref_t, pc));
instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t) pc, opnd1,
ilist, where, &first, &second);
instr_set_ok_to_mangle(first, false/*meta*/);
if (second != NULL)
instr_set_ok_to_mangle(second, false/*meta*/);
/* Increment reg value by pointer size using lea instr */
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg2, DR_REG_NULL, 0,
sizeof(mem_ref_t),
OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* Update the data->buf_ptr */
drmgr_insert_read_tls_field(drcontext, tls_index, ilist, where, reg1);
opnd1 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_ptr));
opnd2 = opnd_create_reg(reg2);
instr = INSTR_CREATE_mov_st(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* we use lea + jecxz trick for better performance
* lea and jecxz won't disturb the eflags, so we won't insert
* code to save and restore application's eflags.
*/
/* lea [reg2 - buf_end] => reg2 */
opnd1 = opnd_create_reg(reg1);
opnd2 = OPND_CREATE_MEMPTR(reg1, offsetof(per_thread_t, buf_end));
instr = INSTR_CREATE_mov_ld(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
opnd1 = opnd_create_reg(reg2);
opnd2 = opnd_create_base_disp(reg1, reg2, 1, 0, OPSZ_lea);
instr = INSTR_CREATE_lea(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jecxz call */
call = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(call);
instr = INSTR_CREATE_jecxz(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* jump restore to skip clean call */
restore = INSTR_CREATE_label(drcontext);
opnd1 = opnd_create_instr(restore);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* clean call */
/* We jump to lean procedure which performs full context switch and
* clean call invocation. This is to reduce the code cache size.
*/
instrlist_meta_preinsert(ilist, where, call);
/* mov restore DR_REG_XCX */
opnd1 = opnd_create_reg(reg2);
/* this is the return address for jumping back from lean procedure */
opnd2 = opnd_create_instr(restore);
/* We could use instrlist_insert_mov_instr_addr(), but with a register
* destination we know we can use a 64-bit immediate.
*/
instr = INSTR_CREATE_mov_imm(drcontext, opnd1, opnd2);
instrlist_meta_preinsert(ilist, where, instr);
/* jmp code_cache */
opnd1 = opnd_create_pc(code_cache);
instr = INSTR_CREATE_jmp(drcontext, opnd1);
instrlist_meta_preinsert(ilist, where, instr);
/* restore %reg */
instrlist_meta_preinsert(ilist, where, restore);
dr_restore_reg(drcontext, ilist, where, reg1, SPILL_SLOT_2);
dr_restore_reg(drcontext, ilist, where, reg2, SPILL_SLOT_3);
}
