@@ -27,6 +27,7 @@ import getopt
insnwidth = 32
insnmask = 0xffffffff
+variablewidth = False
fields = {}
arguments = {}
formats = {}
@@ -289,7 +290,7 @@ class Arguments:
class General:
"""Common code between instruction formats and instruction patterns"""
- def __init__(self, name, lineno, base, fixb, fixm, udfm, fldm, flds):
+ def __init__(self, name, lineno, base, fixb, fixm, udfm, fldm, flds, w):
self.name = name
self.file = input_file
self.lineno = lineno
@@ -299,6 +300,7 @@ class General:
self.undefmask = udfm
self.fieldmask = fldm
self.fields = flds
+ self.width = w
def __str__(self):
return self.name + ' ' + str_match_bits(self.fixedbits, self.fixedmask)
@@ -352,7 +354,7 @@ class Pattern(General):
class MultiPattern(General):
"""Class representing an overlapping set of instruction patterns"""
- def __init__(self, lineno, pats, fixb, fixm, udfm):
+ def __init__(self, lineno, pats, fixb, fixm, udfm, w):
self.file = input_file
self.lineno = lineno
self.pats = pats
@@ -360,6 +362,7 @@ class MultiPattern(General):
self.fixedbits = fixb
self.fixedmask = fixm
self.undefmask = udfm
+ self.width = w
def __str__(self):
r = "{"
@@ -502,7 +505,7 @@ def infer_argument_set(flds):
return arg
-def infer_format(arg, fieldmask, flds):
+def infer_format(arg, fieldmask, flds, width):
global arguments
global formats
global decode_function
@@ -521,6 +524,8 @@ def infer_format(arg, fieldmask, flds):
continue
if fieldmask != fmt.fieldmask:
continue
+ if width != fmt.width:
+ continue
if not eq_fields_for_fmts(flds, fmt.fields):
continue
return (fmt, const_flds)
@@ -529,7 +534,7 @@ def infer_format(arg, fieldmask, flds):
if not arg:
arg = infer_argument_set(flds)
- fmt = Format(name, 0, arg, 0, 0, 0, fieldmask, var_flds)
+ fmt = Format(name, 0, arg, 0, 0, 0, fieldmask, var_flds, width)
formats[name] = fmt
return (fmt, const_flds)
@@ -546,6 +551,7 @@ def parse_generic(lineno, is_format, name, toks):
global re_ident
global insnwidth
global insnmask
+ global variablewidth
fixedmask = 0
fixedbits = 0
@@ -633,8 +639,15 @@ def parse_generic(lineno, is_format, name, toks):
error(lineno, 'invalid token "{0}"'.format(t))
width += shift
+ if variablewidth and width < insnwidth and width % 8 == 0:
+ shift = insnwidth - width
+ fixedbits <<= shift
+ fixedmask <<= shift
+ undefmask <<= shift
+ undefmask |= (1 << shift) - 1
+
# We should have filled in all of the bits of the instruction.
- if not (is_format and width == 0) and width != insnwidth:
+ elif not (is_format and width == 0) and width != insnwidth:
error(lineno, 'definition has {0} bits'.format(width))
# Do not check for fields overlaping fields; one valid usage
@@ -660,7 +673,7 @@ def parse_generic(lineno, is_format, name, toks):
if name in formats:
error(lineno, 'duplicate format name', name)
fmt = Format(name, lineno, arg, fixedbits, fixedmask,
- undefmask, fieldmask, flds)
+ undefmask, fieldmask, flds, width)
formats[name] = fmt
else:
# Patterns can reference a format ...
@@ -670,12 +683,14 @@ def parse_generic(lineno, is_format, name, toks):
error(lineno, 'pattern specifies both format and argument set')
if fixedmask & fmt.fixedmask:
error(lineno, 'pattern fixed bits overlap format fixed bits')
+ if width != fmt.width:
+ error(lineno, 'pattern uses format of different width')
fieldmask |= fmt.fieldmask
fixedbits |= fmt.fixedbits
fixedmask |= fmt.fixedmask
undefmask |= fmt.undefmask
else:
- (fmt, flds) = infer_format(arg, fieldmask, flds)
+ (fmt, flds) = infer_format(arg, fieldmask, flds, width)
arg = fmt.base
for f in flds.keys():
if f not in arg.fields:
@@ -687,7 +702,7 @@ def parse_generic(lineno, is_format, name, toks):
if f not in flds.keys() and f not in fmt.fields.keys():
error(lineno, 'field {0} not initialized'.format(f))
pat = Pattern(name, lineno, fmt, fixedbits, fixedmask,
- undefmask, fieldmask, flds)
+ undefmask, fieldmask, flds, width)
patterns.append(pat)
allpatterns.append(pat)
@@ -727,6 +742,13 @@ def build_multi_pattern(lineno, pats):
if p.lineno < lineno:
lineno = p.lineno
+ width = None
+ for p in pats:
+ if width is None:
+ width = p.width
+ elif width != p.width:
+ error(lineno, 'width mismatch in patterns within braces')
+
repeat = True
while repeat:
if fixedmask == 0:
@@ -742,7 +764,7 @@ def build_multi_pattern(lineno, pats):
else:
repeat = False
- mp = MultiPattern(lineno, pats, fixedbits, fixedmask, undefmask)
+ mp = MultiPattern(lineno, pats, fixedbits, fixedmask, undefmask, width)
patterns.append(mp)
# end build_multi_pattern
@@ -979,13 +1001,14 @@ def main():
global insntype
global insnmask
global decode_function
+ global variablewidth
decode_scope = 'static '
long_opts = ['decode=', 'translate=', 'output=', 'insnwidth=',
- 'static-decode=']
+ 'static-decode=', 'varinsnwidth=']
try:
- (opts, args) = getopt.getopt(sys.argv[1:], 'o:w:', long_opts)
+ (opts, args) = getopt.getopt(sys.argv[1:], 'o:vw:', long_opts)
except getopt.GetoptError as err:
error(0, err)
for o, a in opts:
@@ -999,7 +1022,9 @@ def main():
elif o == '--translate':
translate_prefix = a
translate_scope = ''
- elif o in ('-w', '--insnwidth'):
+ elif o in ('-w', '--insnwidth', '--varinsnwidth'):
+ if o == '--varinsnwidth':
+ variablewidth = True
insnwidth = int(a)
if insnwidth == 16:
insntype = 'uint16_t'
Assuming that the ISA clearly describes how to determine the length of the instruction, and the ISA has a reasonable maximum instruction length, the input to the decoder can be right-justified in an appropriate insn word. This is not 100% convenient, as out-of-line %fields are numbered relative to the maximum instruction length, but this appears to still be usable. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- scripts/decodetree.py | 49 ++++++++++++++++++++++++++++++++----------- 1 file changed, 37 insertions(+), 12 deletions(-) -- 2.17.1