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instrs: Add reserved NOP/PREFETCH as weak opcodes

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This commit is contained in:
Alexis Engelke
2021-01-10 16:50:27 +01:00
parent f1e18c208c
commit 80df5ff47c
3 changed files with 51 additions and 25 deletions
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26
instrs.txt
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@@ -347,11 +347,8 @@ F2.0f09 NP - - - - WBINVD
0f0d/0m M MEM8 - - - PREFETCH 0f0d/0m M MEM8 - - - PREFETCH
0f0d/1m M MEM8 - - - PREFETCHW 0f0d/1m M MEM8 - - - PREFETCHW
0f0d/2m M MEM8 - - - PREFETCHWT1 0f0d/2m M MEM8 - - - PREFETCHWT1
0f0d/3m M MEM8 - - - RESERVED_PREFETCH # All other slots are reserved, AMD maps them to /0
0f0d/4m M MEM8 - - - RESERVED_PREFETCH *0f0d/m M MEM8 - - - RESERVED_PREFETCH ONLYAMD
0f0d/5m M MEM8 - - - RESERVED_PREFETCH
0f0d/6m M MEM8 - - - RESERVED_PREFETCH
0f0d/7m M MEM8 - - - RESERVED_PREFETCH
0f0e NP - - - - FEMMS ONLYAMD 0f0e NP - - - - FEMMS ONLYAMD
# TODO: actually decode 3DNow! instructions. Given that 3DNow! no longer exists, # TODO: actually decode 3DNow! instructions. Given that 3DNow! no longer exists,
# this is unlikely to happen, though. # this is unlikely to happen, though.
@@ -360,15 +357,16 @@ F2.0f09 NP - - - - WBINVD
0f18/1m M MEM8 - - - PREFETCHT0 0f18/1m M MEM8 - - - PREFETCHT0
0f18/2m M MEM8 - - - PREFETCHT1 0f18/2m M MEM8 - - - PREFETCHT1
0f18/3m M MEM8 - - - PREFETCHT2 0f18/3m M MEM8 - - - PREFETCHT2
0f18/0r M GP - - - RESERVED_NOP # Reserved NOPs are weak, they can be overridden by other instructions.
0f18/1r M GP - - - RESERVED_NOP *0f18 MR GP GP - - RESERVED_NOP
0f18/2r M GP - - - RESERVED_NOP *0f19 MR GP GP - - RESERVED_NOP
0f18/3r M GP - - - RESERVED_NOP *0f1a MR GP GP - - RESERVED_NOP
0f18/4 M GP - - - RESERVED_NOP *0f1b MR GP GP - - RESERVED_NOP
0f18/5 M GP - - - RESERVED_NOP *0f1c MR GP GP - - RESERVED_NOP
0f18/6 M GP - - - RESERVED_NOP *0f1d MR GP GP - - RESERVED_NOP
0f18/7 M GP - - - RESERVED_NOP *0f1e MR GP GP - - RESERVED_NOP
0f1f M GP - - - NOP *0f1f MR GP GP - - RESERVED_NOP
0f1f/0 M GP - - - NOP
0f20 MR GP CR - - MOV_CR DEF64 IGN66 0f20 MR GP CR - - MOV_CR DEF64 IGN66
0f21 MR GP DR - - MOV_DR DEF64 IGN66 0f21 MR GP DR - - MOV_DR DEF64 IGN66
0f22 RM CR GP - - MOV_CR DEF64 IGN66 0f22 RM CR GP - - MOV_CR DEF64 IGN66

46
parseinstrs.py
View File

@@ -345,7 +345,7 @@ class Table:
new_items = old.items[:idx] + (entry_name,) + old.items[idx+1:] new_items = old.items[:idx] + (entry_name,) + old.items[idx+1:]
self.data[name] = TrieEntry(old.kind, new_items, None) self.data[name] = TrieEntry(old.kind, new_items, None)
def add_opcode(self, opcode, instr_encoding, root_idx=0): def _walk_opcode(self, opcode, root_idx):
name = "t{},{}".format(root_idx, format_opcode(opcode)) name = "t{},{}".format(root_idx, format_opcode(opcode))
tn = "root%d"%root_idx tn = "root%d"%root_idx
@@ -361,12 +361,33 @@ class Table:
if self.data[tn].kind != kind: if self.data[tn].kind != kind:
raise Exception("{}, have {}, want {}".format( raise Exception("{}, have {}, want {}".format(
name, self.data[tn].kind, kind)) name, self.data[tn].kind, kind))
return tn
def _add_encoding(self, instr_encoding):
desc_idx = self.descs_map.get(instr_encoding) desc_idx = self.descs_map.get(instr_encoding)
if desc_idx is None: if desc_idx is None:
desc_idx = self.descs_map[instr_encoding] = len(self.descs) desc_idx = self.descs_map[instr_encoding] = len(self.descs)
self.descs.append(instr_encoding) self.descs.append(instr_encoding)
self._update_table(tn, opcode[-1][1], name, TrieEntry.instr(desc_idx)) return TrieEntry.instr(desc_idx)
def add_opcode(self, opcode, instr_encoding, root_idx=0):
name = "t{},{}".format(root_idx, format_opcode(opcode))
tn = self._walk_opcode(opcode, root_idx)
desc_entry = self._add_encoding(instr_encoding)
self._update_table(tn, opcode[-1][1], name, desc_entry)
def fill_free(self, opcode, instr_encoding, root_idx=0):
desc_entry = self._add_encoding(instr_encoding)
tn = self._walk_opcode(opcode, root_idx)
queue = [(tn, opcode[-1][1])]
while queue:
tn, idx = queue.pop()
entry = self.data[tn].items[idx]
if not entry:
self._update_table(tn, idx, f"tn,*{idx:x}", desc_entry)
else:
for i in range(len(self.data[entry].items)):
queue.append((entry, i))
def deduplicate(self): def deduplicate(self):
parents = defaultdict(set) parents = defaultdict(set)
@@ -468,10 +489,8 @@ template = """// Auto-generated file -- do not modify!
def encode_table(entries): def encode_table(entries):
mnemonics = defaultdict(list) mnemonics = defaultdict(list)
mnemonics["FE_NOP"].append(("NP", 0, 0, "0x90")) mnemonics["FE_NOP"].append(("NP", 0, 0, "0x90"))
for opcode, desc in entries: for weak, opcode, desc in entries:
if desc.mnemonic[:9] == "RESERVED_": if weak or "ONLY32" in desc.flags:
continue
if "ONLY32" in desc.flags:
continue continue
opsizes = {8} if "SIZE_8" in desc.flags else {16, 32, 64} opsizes = {8} if "SIZE_8" in desc.flags else {16, 32, 64}
@@ -629,30 +648,37 @@ if __name__ == "__main__":
entries = [] entries = []
for line in args.table.read().splitlines(): for line in args.table.read().splitlines():
if not line or line[0] == "#": continue if not line or line[0] == "#": continue
line, weak = (line, False) if line[0] != "*" else (line[1:], True)
opcode_string, desc_string = tuple(line.split(maxsplit=1)) opcode_string, desc_string = tuple(line.split(maxsplit=1))
opcode, desc = Opcode.parse(opcode_string), InstrDesc.parse(desc_string) opcode, desc = Opcode.parse(opcode_string), InstrDesc.parse(desc_string)
if "UNDOC" not in desc.flags or args.with_undoc: if "UNDOC" not in desc.flags or args.with_undoc:
entries.append((opcode, desc)) entries.append((weak, opcode, desc))
mnemonics = sorted({desc.mnemonic for _, desc in entries}) mnemonics = sorted({desc.mnemonic for _, _, desc in entries})
decode_mnems_lines = [f"FD_MNEMONIC({m},{i})\n" for i, m in enumerate(mnemonics)] decode_mnems_lines = [f"FD_MNEMONIC({m},{i})\n" for i, m in enumerate(mnemonics)]
args.decode_mnems.write("".join(decode_mnems_lines)) args.decode_mnems.write("".join(decode_mnems_lines))
modes = [32, 64] modes = [32, 64]
table = Table(root_count=len(args.modes)) table = Table(root_count=len(args.modes))
for opcode, desc in entries: weak_opcodes = []
for weak, opcode, desc in entries:
for i, mode in enumerate(args.modes): for i, mode in enumerate(args.modes):
if "ONLY%d"%(96-mode) not in desc.flags: if "ONLY%d"%(96-mode) not in desc.flags:
ign66 = opcode.prefix in ("NP", "66", "F2", "F3") ign66 = opcode.prefix in ("NP", "66", "F2", "F3")
for opcode_path in opcode.for_trie(): for opcode_path in opcode.for_trie():
if weak:
weak_opcodes.append((opcode_path, desc.encode(ign66), i))
else:
table.add_opcode(opcode_path, desc.encode(ign66), i) table.add_opcode(opcode_path, desc.encode(ign66), i)
for k in weak_opcodes:
table.fill_free(*k)
table.deduplicate() table.deduplicate()
table_data, annotations, root_offsets, descs = table.compile() table_data, annotations, root_offsets, descs = table.compile()
mnemonics_intel = [m.replace("SSE_", "").replace("MMX_", "") mnemonics_intel = [m.replace("SSE_", "").replace("MMX_", "")
.replace("MOVABS", "MOV") .replace("MOVABS", "MOV").replace("RESERVED_", "")
.replace("JMPF", "JMP FAR").replace("CALLF", "CALL FAR") .replace("JMPF", "JMP FAR").replace("CALLF", "CALL FAR")
.replace("_S2G", "").replace("_G2S", "") .replace("_S2G", "").replace("_G2S", "")
.replace("_CR", "").replace("_DR", "") .replace("_CR", "").replace("_DR", "")

2
tests/test_decode.c
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@@ -111,6 +111,8 @@ main(int argc, char** argv)
TEST64("\x44\x8c\xf8", "UD"); // no segment register 7 TEST64("\x44\x8c\xf8", "UD"); // no segment register 7
TEST("\x8e\xc0", "mov es, ax"); TEST("\x8e\xc0", "mov es, ax");
TEST("\x8e\xc8", "UD"); // No mov cs, eax TEST("\x8e\xc8", "UD"); // No mov cs, eax
TEST("\x0f\x1e\xc0", "nop eax, eax"); // reserved nop
TEST("\x0f\x1e\x04\x25\x01\x00\x00\x00", "nop dword ptr [0x1], eax"); // reserved nop
TEST("\xd8\xc1", "fadd st(0), st(1)"); TEST("\xd8\xc1", "fadd st(0), st(1)");
TEST("\xdc\xc1", "fadd st(1), st(0)"); TEST("\xdc\xc1", "fadd st(1), st(0)");
TEST64("\x41\xd8\xc1", "fadd st(0), st(1)"); // REX.B ignored TEST64("\x41\xd8\xc1", "fadd st(0), st(1)"); // REX.B ignored