alistair23-linux/arch/x86/tools/gen-insn-attr-x86.awk
Masami Hiramatsu 436d03faf6 x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix
Fix the x86 instruction decoder to decode bsr/bsf/jmpe with
operand-size prefix (66h). This fixes the test case failure
reported by Linus, attached below.

bsf/bsr/jmpe have a special encoding. Opcode map in
Intel Software Developers Manual vol2 says they have
TZCNT/LZCNT variants if it has F3h prefix. However, there
is no information if it has other 66h or F2h prefixes.
Current instruction decoder supposes that those are
bad instructions, but it actually accepts at least
operand-size prefixes.

H. Peter Anvin further explains:

 " TZCNT/LZCNT are F3 + BSF/BSR exactly because the F2 and
   F3 prefixes have historically been no-ops with most instructions.
   This allows software to unconditionally use the prefixed versions
   and get TZCNT/LZCNT on the processors that have them if they don't
   care about the difference. "

This fixes errors reported by test_get_len:

  Warning: arch/x86/tools/test_get_len found difference at <em_bsf>:ffffffff81036d87
  Warning: ffffffff81036de5:	66 0f bc c2          	bsf    %dx,%ax
  Warning: objdump says 4 bytes, but insn_get_length() says 3
  Warning: arch/x86/tools/test_get_len found difference at <em_bsr>:ffffffff81036ea6
  Warning: ffffffff81036f04:	66 0f bd c2          	bsr    %dx,%ax
  Warning: objdump says 4 bytes, but insn_get_length() says 3
  Warning: decoded and checked 13298882 instructions with 2 warnings

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <yrl.pp-manager.tt@hitachi.com>
Link: http://lkml.kernel.org/r/20120604150911.22338.43296.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06 08:54:18 +02:00

386 lines
9.2 KiB
Awk

#!/bin/awk -f
# gen-insn-attr-x86.awk: Instruction attribute table generator
# Written by Masami Hiramatsu <mhiramat@redhat.com>
#
# Usage: awk -f gen-insn-attr-x86.awk x86-opcode-map.txt > inat-tables.c
# Awk implementation sanity check
function check_awk_implement() {
if (sprintf("%x", 0) != "0")
return "Your awk has a printf-format problem."
return ""
}
# Clear working vars
function clear_vars() {
delete table
delete lptable2
delete lptable1
delete lptable3
eid = -1 # escape id
gid = -1 # group id
aid = -1 # AVX id
tname = ""
}
BEGIN {
# Implementation error checking
awkchecked = check_awk_implement()
if (awkchecked != "") {
print "Error: " awkchecked > "/dev/stderr"
print "Please try to use gawk." > "/dev/stderr"
exit 1
}
# Setup generating tables
print "/* x86 opcode map generated from x86-opcode-map.txt */"
print "/* Do not change this code. */\n"
ggid = 1
geid = 1
gaid = 0
delete etable
delete gtable
delete atable
opnd_expr = "^[A-Za-z/]"
ext_expr = "^\\("
sep_expr = "^\\|$"
group_expr = "^Grp[0-9A-Za-z]+"
imm_expr = "^[IJAOL][a-z]"
imm_flag["Ib"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
imm_flag["Jb"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
imm_flag["Iw"] = "INAT_MAKE_IMM(INAT_IMM_WORD)"
imm_flag["Id"] = "INAT_MAKE_IMM(INAT_IMM_DWORD)"
imm_flag["Iq"] = "INAT_MAKE_IMM(INAT_IMM_QWORD)"
imm_flag["Ap"] = "INAT_MAKE_IMM(INAT_IMM_PTR)"
imm_flag["Iz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)"
imm_flag["Jz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)"
imm_flag["Iv"] = "INAT_MAKE_IMM(INAT_IMM_VWORD)"
imm_flag["Ob"] = "INAT_MOFFSET"
imm_flag["Ov"] = "INAT_MOFFSET"
imm_flag["Lx"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
modrm_expr = "^([CDEGMNPQRSUVW/][a-z]+|NTA|T[012])"
force64_expr = "\\([df]64\\)"
rex_expr = "^REX(\\.[XRWB]+)*"
fpu_expr = "^ESC" # TODO
lprefix1_expr = "\\((66|!F3)\\)"
lprefix2_expr = "\\(F3\\)"
lprefix3_expr = "\\((F2|!F3)\\)"
lprefix_expr = "\\((66|F2|F3)\\)"
max_lprefix = 4
# All opcodes starting with lower-case 'v' or with (v1) superscript
# accepts VEX prefix
vexok_opcode_expr = "^v.*"
vexok_expr = "\\(v1\\)"
# All opcodes with (v) superscript supports *only* VEX prefix
vexonly_expr = "\\(v\\)"
prefix_expr = "\\(Prefix\\)"
prefix_num["Operand-Size"] = "INAT_PFX_OPNDSZ"
prefix_num["REPNE"] = "INAT_PFX_REPNE"
prefix_num["REP/REPE"] = "INAT_PFX_REPE"
prefix_num["LOCK"] = "INAT_PFX_LOCK"
prefix_num["SEG=CS"] = "INAT_PFX_CS"
prefix_num["SEG=DS"] = "INAT_PFX_DS"
prefix_num["SEG=ES"] = "INAT_PFX_ES"
prefix_num["SEG=FS"] = "INAT_PFX_FS"
prefix_num["SEG=GS"] = "INAT_PFX_GS"
prefix_num["SEG=SS"] = "INAT_PFX_SS"
prefix_num["Address-Size"] = "INAT_PFX_ADDRSZ"
prefix_num["VEX+1byte"] = "INAT_PFX_VEX2"
prefix_num["VEX+2byte"] = "INAT_PFX_VEX3"
clear_vars()
}
function semantic_error(msg) {
print "Semantic error at " NR ": " msg > "/dev/stderr"
exit 1
}
function debug(msg) {
print "DEBUG: " msg
}
function array_size(arr, i,c) {
c = 0
for (i in arr)
c++
return c
}
/^Table:/ {
print "/* " $0 " */"
if (tname != "")
semantic_error("Hit Table: before EndTable:.");
}
/^Referrer:/ {
if (NF != 1) {
# escape opcode table
ref = ""
for (i = 2; i <= NF; i++)
ref = ref $i
eid = escape[ref]
tname = sprintf("inat_escape_table_%d", eid)
}
}
/^AVXcode:/ {
if (NF != 1) {
# AVX/escape opcode table
aid = $2
if (gaid <= aid)
gaid = aid + 1
if (tname == "") # AVX only opcode table
tname = sprintf("inat_avx_table_%d", $2)
}
if (aid == -1 && eid == -1) # primary opcode table
tname = "inat_primary_table"
}
/^GrpTable:/ {
print "/* " $0 " */"
if (!($2 in group))
semantic_error("No group: " $2 )
gid = group[$2]
tname = "inat_group_table_" gid
}
function print_table(tbl,name,fmt,n)
{
print "const insn_attr_t " name " = {"
for (i = 0; i < n; i++) {
id = sprintf(fmt, i)
if (tbl[id])
print " [" id "] = " tbl[id] ","
}
print "};"
}
/^EndTable/ {
if (gid != -1) {
# print group tables
if (array_size(table) != 0) {
print_table(table, tname "[INAT_GROUP_TABLE_SIZE]",
"0x%x", 8)
gtable[gid,0] = tname
}
if (array_size(lptable1) != 0) {
print_table(lptable1, tname "_1[INAT_GROUP_TABLE_SIZE]",
"0x%x", 8)
gtable[gid,1] = tname "_1"
}
if (array_size(lptable2) != 0) {
print_table(lptable2, tname "_2[INAT_GROUP_TABLE_SIZE]",
"0x%x", 8)
gtable[gid,2] = tname "_2"
}
if (array_size(lptable3) != 0) {
print_table(lptable3, tname "_3[INAT_GROUP_TABLE_SIZE]",
"0x%x", 8)
gtable[gid,3] = tname "_3"
}
} else {
# print primary/escaped tables
if (array_size(table) != 0) {
print_table(table, tname "[INAT_OPCODE_TABLE_SIZE]",
"0x%02x", 256)
etable[eid,0] = tname
if (aid >= 0)
atable[aid,0] = tname
}
if (array_size(lptable1) != 0) {
print_table(lptable1,tname "_1[INAT_OPCODE_TABLE_SIZE]",
"0x%02x", 256)
etable[eid,1] = tname "_1"
if (aid >= 0)
atable[aid,1] = tname "_1"
}
if (array_size(lptable2) != 0) {
print_table(lptable2,tname "_2[INAT_OPCODE_TABLE_SIZE]",
"0x%02x", 256)
etable[eid,2] = tname "_2"
if (aid >= 0)
atable[aid,2] = tname "_2"
}
if (array_size(lptable3) != 0) {
print_table(lptable3,tname "_3[INAT_OPCODE_TABLE_SIZE]",
"0x%02x", 256)
etable[eid,3] = tname "_3"
if (aid >= 0)
atable[aid,3] = tname "_3"
}
}
print ""
clear_vars()
}
function add_flags(old,new) {
if (old && new)
return old " | " new
else if (old)
return old
else
return new
}
# convert operands to flags.
function convert_operands(count,opnd, i,j,imm,mod)
{
imm = null
mod = null
for (j = 1; j <= count; j++) {
i = opnd[j]
if (match(i, imm_expr) == 1) {
if (!imm_flag[i])
semantic_error("Unknown imm opnd: " i)
if (imm) {
if (i != "Ib")
semantic_error("Second IMM error")
imm = add_flags(imm, "INAT_SCNDIMM")
} else
imm = imm_flag[i]
} else if (match(i, modrm_expr))
mod = "INAT_MODRM"
}
return add_flags(imm, mod)
}
/^[0-9a-f]+\:/ {
if (NR == 1)
next
# get index
idx = "0x" substr($1, 1, index($1,":") - 1)
if (idx in table)
semantic_error("Redefine " idx " in " tname)
# check if escaped opcode
if ("escape" == $2) {
if ($3 != "#")
semantic_error("No escaped name")
ref = ""
for (i = 4; i <= NF; i++)
ref = ref $i
if (ref in escape)
semantic_error("Redefine escape (" ref ")")
escape[ref] = geid
geid++
table[idx] = "INAT_MAKE_ESCAPE(" escape[ref] ")"
next
}
variant = null
# converts
i = 2
while (i <= NF) {
opcode = $(i++)
delete opnds
ext = null
flags = null
opnd = null
# parse one opcode
if (match($i, opnd_expr)) {
opnd = $i
count = split($(i++), opnds, ",")
flags = convert_operands(count, opnds)
}
if (match($i, ext_expr))
ext = $(i++)
if (match($i, sep_expr))
i++
else if (i < NF)
semantic_error($i " is not a separator")
# check if group opcode
if (match(opcode, group_expr)) {
if (!(opcode in group)) {
group[opcode] = ggid
ggid++
}
flags = add_flags(flags, "INAT_MAKE_GROUP(" group[opcode] ")")
}
# check force(or default) 64bit
if (match(ext, force64_expr))
flags = add_flags(flags, "INAT_FORCE64")
# check REX prefix
if (match(opcode, rex_expr))
flags = add_flags(flags, "INAT_MAKE_PREFIX(INAT_PFX_REX)")
# check coprocessor escape : TODO
if (match(opcode, fpu_expr))
flags = add_flags(flags, "INAT_MODRM")
# check VEX codes
if (match(ext, vexonly_expr))
flags = add_flags(flags, "INAT_VEXOK | INAT_VEXONLY")
else if (match(ext, vexok_expr) || match(opcode, vexok_opcode_expr))
flags = add_flags(flags, "INAT_VEXOK")
# check prefixes
if (match(ext, prefix_expr)) {
if (!prefix_num[opcode])
semantic_error("Unknown prefix: " opcode)
flags = add_flags(flags, "INAT_MAKE_PREFIX(" prefix_num[opcode] ")")
}
if (length(flags) == 0)
continue
# check if last prefix
if (match(ext, lprefix1_expr)) {
lptable1[idx] = add_flags(lptable1[idx],flags)
variant = "INAT_VARIANT"
}
if (match(ext, lprefix2_expr)) {
lptable2[idx] = add_flags(lptable2[idx],flags)
variant = "INAT_VARIANT"
}
if (match(ext, lprefix3_expr)) {
lptable3[idx] = add_flags(lptable3[idx],flags)
variant = "INAT_VARIANT"
}
if (!match(ext, lprefix_expr)){
table[idx] = add_flags(table[idx],flags)
}
}
if (variant)
table[idx] = add_flags(table[idx],variant)
}
END {
if (awkchecked != "")
exit 1
# print escape opcode map's array
print "/* Escape opcode map array */"
print "const insn_attr_t const *inat_escape_tables[INAT_ESC_MAX + 1]" \
"[INAT_LSTPFX_MAX + 1] = {"
for (i = 0; i < geid; i++)
for (j = 0; j < max_lprefix; j++)
if (etable[i,j])
print " ["i"]["j"] = "etable[i,j]","
print "};\n"
# print group opcode map's array
print "/* Group opcode map array */"
print "const insn_attr_t const *inat_group_tables[INAT_GRP_MAX + 1]"\
"[INAT_LSTPFX_MAX + 1] = {"
for (i = 0; i < ggid; i++)
for (j = 0; j < max_lprefix; j++)
if (gtable[i,j])
print " ["i"]["j"] = "gtable[i,j]","
print "};\n"
# print AVX opcode map's array
print "/* AVX opcode map array */"
print "const insn_attr_t const *inat_avx_tables[X86_VEX_M_MAX + 1]"\
"[INAT_LSTPFX_MAX + 1] = {"
for (i = 0; i < gaid; i++)
for (j = 0; j < max_lprefix; j++)
if (atable[i,j])
print " ["i"]["j"] = "atable[i,j]","
print "};"
}