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//:: Check that the different operands of an instruction aren't too large for their bitfields.
void test_check_bitfield_sizes() {
Hide_errors = true;
run(
"== code 0x1\n"
"01/add 4/mod 3/rm32 1/r32\n" // add ECX to EBX
);
CHECK_TRACE_CONTENTS(
"error: '4/mod' too large to fit in bitfield mod\n"
);
}
:(before "End Globals")
map<string, uint32_t> Operand_bound;
:(before "End One-time Setup")
put_new(Operand_bound, "subop", 1<<3);
put_new(Operand_bound, "mod", 1<<2);
put_new(Operand_bound, "rm32", 1<<3);
put_new(Operand_bound, "base", 1<<3);
put_new(Operand_bound, "index", 1<<3);
put_new(Operand_bound, "scale", 1<<2);
put_new(Operand_bound, "r32", 1<<3);
put_new(Operand_bound, "disp8", 1<<8);
put_new(Operand_bound, "disp16", 1<<16);
// no bound needed for disp32
put_new(Operand_bound, "imm8", 1<<8);
// no bound needed for imm32
:(before "Pack Operands(segment code)")
check_operand_bounds(code);
if (trace_contains_errors()) return;
:(code)
void check_operand_bounds(const segment& code) {
trace(3, "transform") << "-- check operand bounds" << end();
for (int i = 0; i < SIZE(code.lines); ++i) {
const line& inst = code.lines.at(i);
for (int j = first_operand(inst); j < SIZE(inst.words); ++j)
check_operand_bounds(inst.words.at(j));
if (trace_contains_errors()) return; // stop at the first mal-formed instruction
}
}
void check_operand_bounds(const word& w) {
for (map<string, uint32_t>::iterator p = Operand_bound.begin(); p != Operand_bound.end(); ++p) {
if (!has_operand_metadata(w, p->first)) continue;
if (!looks_like_hex_int(w.data)) continue; // later transforms are on their own to do their own bounds checking
int32_t x = parse_int(w.data);
if (x >= 0) {
if (p->first == "disp8" || p->first == "disp16") {
if (static_cast<uint32_t>(x) >= p->second/2)
raise << "'" << w.original << "' too large to fit in signed bitfield " << p->first << '\n' << end();
}
else {
if (static_cast<uint32_t>(x) >= p->second)
raise << "'" << w.original << "' too large to fit in bitfield " << p->first << '\n' << end();
}
}
else {
// hacky? assuming bound is a power of 2
if (x < -1*static_cast<int32_t>(p->second/2))
raise << "'" << w.original << "' too large to fit in bitfield " << p->first << '\n' << end();
}
}
}
void test_check_bitfield_sizes_for_imm8() {
run(
"== code 0x1\n"
"c1/shift 4/subop/left 3/mod/direct 1/rm32/ECX 0xff/imm8" // shift EBX left
);
CHECK(!trace_contains_errors());
}
void test_check_bitfield_sizes_for_imm8_error() {
Hide_errors = true;
run(
"== code 0x1\n"
"c1/shift 4/subop/left 3/mod/direct 1/rm32/ECX 0x100/imm8" // shift EBX left
);
CHECK_TRACE_CONTENTS(
"error: '0x100/imm8' too large to fit in bitfield imm8\n"
);
}
void test_check_bitfield_sizes_for_negative_imm8() {
run(
"== code 0x1\n"
"c1/shift 4/subop/left 3/mod/direct 1/rm32/ECX -0x80/imm8" // shift EBX left
);
CHECK(!trace_contains_errors());
}
void test_check_bitfield_sizes_for_negative_imm8_error() {
Hide_errors = true;
run(
"== code 0x1\n"
"c1/shift 4/subop/left 3/mod/direct 1/rm32/ECX -0x81/imm8" // shift EBX left
);
CHECK_TRACE_CONTENTS(
"error: '-0x81/imm8' too large to fit in bitfield imm8\n"
);
}
void test_check_bitfield_sizes_for_disp8() {
// not bothering to run
transform(
"== code 0x1\n"
"01/add 1/mod/*+disp8 3/rm32 1/r32 0x7f/disp8\n" // add ECX to *(EBX+0x7f)
);
CHECK(!trace_contains_errors());
}
void test_check_bitfield_sizes_for_disp8_error() {
Hide_errors = true;
run(
"== code 0x1\n"
"01/add 1/mod/*+disp8 3/rm32 1/r32 0x80/disp8\n" // add ECX to *(EBX+0x80)
);
CHECK_TRACE_CONTENTS(
"error: '0x80/disp8' too large to fit in signed bitfield disp8\n"
);
}
void test_check_bitfield_sizes_for_negative_disp8() {
// not bothering to run
transform(
"== code 0x1\n"
"01/add 1/mod/*+disp8 3/rm32 1/r32 -0x80/disp8\n" // add ECX to *(EBX-0x80)
);
CHECK(!trace_contains_errors());
}
void test_check_bitfield_sizes_for_negative_disp8_error() {
Hide_errors = true;
run(
"== code 0x1\n"
"01/add 1/mod/*+disp8 3/rm32 1/r32 -0x81/disp8\n" // add ECX to *(EBX-0x81)
);
CHECK_TRACE_CONTENTS(
"error: '-0x81/disp8' too large to fit in bitfield disp8\n"
);
}
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