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Change how memory operands are handled in ISA descriptions.

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Should enable implementation of split-phase timing loads
with new memory model.
May create slight timing differences under FullCPU, as I
believe we were not handling software prefetches correctly
before when the split MemAcc/Exec model was used.  I haven't
looked into this in any detail though.

arch/alpha/isa/decoder.isa:
    HwLoadStore format split into separate HwLoad and
    HwStore formats.
    Copy instructions now fall under MiscPrefetch format.
    Mem_write_result is now just write_result in store
    conditionals.
arch/alpha/isa/mem.isa:
    Split MemAccExecute and LoadStoreExecute templates
    into separate templates for loads and stores; now
    that memory operands are handled differently from
    registers, it's impossible to have a single template
    serve both.
    Also unified the handling of "regular" prefetches
    (loads to r31) and "misc" prefetches (e.g., wh64)
    under the new scheme.  It looks like SW prefetches
    were not handled correctly in FullCPU up til now,
    since we generated an execute() method for the outer
    instruction but didn't generate a proper method for
    MemAcc::execute() (instead getting a default no-op
    method for that).
arch/alpha/isa/pal.isa:
    Split HwLoadStore into separate HwLoad and HwStore
    formats to select proper template (see change to
    mem.isa in this changeset).
arch/isa_parser.py:
    Stop trying to treat memory operands like register
    operands, since we never used them in a uniform way
    anyway, and it made it impossible to do split-phase
    loads as needed for the new CPU model.  Now there's no
    more 'op_mem_rd', 'op_nonmem_rd', etc.: 'op_rd' just does
    register operands, and the template code is responsible
    for formulating the call to the memory system.  Right now
    the only thing exported by InstObjParams is a new attribute
    'mem_acc_size' which gives the memory access size in bits,
    though more attributes can be added if needed.

    Also moved code in findOperands() method to
    OperandDescriptorList.__init__(), which is where it belongs.

--HG--
extra : convert_revision : 6d53d07e0c5e828455834ded4395fa40f9146a34
This commit is contained in:
Steve Reinhardt 2006-02-10 09:12:55 -05:00
parent dd473ecd57
commit 3923eec0ef
4 changed files with 231 additions and 145 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

20
arch/alpha/isa/decoder.isa
View file

@ -40,9 +40,9 @@ decode OPCODE default Unknown::unknown() {
0x23: ldt({{ EA = Rb + disp; }}, {{ Fa = Mem.df; }});
0x2a: ldl_l({{ EA = Rb + disp; }}, {{ Ra.sl = Mem.sl; }}, LOCKED);
0x2b: ldq_l({{ EA = Rb + disp; }}, {{ Ra.uq = Mem.uq; }}, LOCKED);
0x20: copy_load({{EA = Ra;}},
{{fault = xc->copySrcTranslate(EA);}},
IsMemRef, IsLoad, IsCopy);
0x20: MiscPrefetch::copy_load({{ EA = Ra; }},
{{ fault = xc->copySrcTranslate(EA); }},
IsMemRef, IsLoad, IsCopy);
}
format LoadOrPrefetch {
@ -62,21 +62,21 @@ decode OPCODE default Unknown::unknown() {
0x0f: stq_u({{ EA = (Rb + disp) & ~7; }}, {{ Mem.uq = Ra.uq; }});
0x26: sts({{ EA = Rb + disp; }}, {{ Mem.ul = t_to_s(Fa.uq); }});
0x27: stt({{ EA = Rb + disp; }}, {{ Mem.df = Fa; }});
0x24: copy_store({{EA = Rb;}},
{{fault = xc->copy(EA);}},
IsMemRef, IsStore, IsCopy);
0x24: MiscPrefetch::copy_store({{ EA = Rb; }},
{{ fault = xc->copy(EA); }},
IsMemRef, IsStore, IsCopy);
}
format StoreCond {
0x2e: stl_c({{ EA = Rb + disp; }}, {{ Mem.ul = Ra<31:0>; }},
{{
uint64_t tmp = Mem_write_result;
uint64_t tmp = write_result;
// see stq_c
Ra = (tmp == 0 || tmp == 1) ? tmp : Ra;
}}, LOCKED);
0x2f: stq_c({{ EA = Rb + disp; }}, {{ Mem.uq = Ra; }},
{{
uint64_t tmp = Mem_write_result;
uint64_t tmp = write_result;
// If the write operation returns 0 or 1, then
// this was a conventional store conditional,
// and the value indicates the success/failure
@ -704,12 +704,14 @@ decode OPCODE default Unknown::unknown() {
#endif
#if FULL_SYSTEM
format HwLoadStore {
format HwLoad {
0x1b: decode HW_LDST_QUAD {
0: hw_ld({{ EA = (Rb + disp) & ~3; }}, {{ Ra = Mem.ul; }}, L);
1: hw_ld({{ EA = (Rb + disp) & ~7; }}, {{ Ra = Mem.uq; }}, Q);
}
}
format HwStore {
0x1f: decode HW_LDST_COND {
0: decode HW_LDST_QUAD {
0: hw_st({{ EA = (Rb + disp) & ~3; }},

160
arch/alpha/isa/mem.isa
View file

@ -214,7 +214,7 @@ def template EACompExecute {{
}
}};
def template MemAccExecute {{
def template LoadMemAccExecute {{
Fault
%(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
@ -224,24 +224,16 @@ def template MemAccExecute {{
%(fp_enable_check)s;
%(op_decl)s;
%(op_nonmem_rd)s;
%(op_rd)s;
EA = xc->getEA();
if (fault == No_Fault) {
%(op_mem_rd)s;
fault = xc->read(EA, (uint%(mem_acc_size)d_t&)Mem, memAccessFlags);
%(code)s;
}
if (fault == No_Fault) {
%(op_mem_wb)s;
}
if (fault == No_Fault) {
%(postacc_code)s;
}
if (fault == No_Fault) {
%(op_nonmem_wb)s;
%(op_wb)s;
}
return fault;
@ -249,7 +241,7 @@ def template MemAccExecute {{
}};
def template LoadStoreExecute {{
def template LoadExecute {{
Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
{
@ -258,24 +250,16 @@ def template LoadStoreExecute {{
%(fp_enable_check)s;
%(op_decl)s;
%(op_nonmem_rd)s;
%(op_rd)s;
%(ea_code)s;
if (fault == No_Fault) {
%(op_mem_rd)s;
fault = xc->read(EA, (uint%(mem_acc_size)d_t&)Mem, memAccessFlags);
%(memacc_code)s;
}
if (fault == No_Fault) {
%(op_mem_wb)s;
}
if (fault == No_Fault) {
%(postacc_code)s;
}
if (fault == No_Fault) {
%(op_nonmem_wb)s;
%(op_wb)s;
}
return fault;
@ -283,7 +267,100 @@ def template LoadStoreExecute {{
}};
def template PrefetchExecute {{
def template StoreMemAccExecute {{
Fault
%(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
{
Addr EA;
Fault fault = No_Fault;
uint64_t write_result = 0;
%(fp_enable_check)s;
%(op_decl)s;
%(op_rd)s;
EA = xc->getEA();
if (fault == No_Fault) {
%(code)s;
}
if (fault == No_Fault) {
fault = xc->write((uint%(mem_acc_size)d_t&)Mem, EA,
memAccessFlags, &write_result);
if (traceData) { traceData->setData(Mem); }
}
if (fault == No_Fault) {
%(postacc_code)s;
}
if (fault == No_Fault) {
%(op_wb)s;
}
return fault;
}
}};
def template StoreExecute {{
Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
{
Addr EA;
Fault fault = No_Fault;
uint64_t write_result = 0;
%(fp_enable_check)s;
%(op_decl)s;
%(op_rd)s;
%(ea_code)s;
if (fault == No_Fault) {
%(memacc_code)s;
}
if (fault == No_Fault) {
fault = xc->write((uint%(mem_acc_size)d_t&)Mem, EA,
memAccessFlags, &write_result);
if (traceData) { traceData->setData(Mem); }
}
if (fault == No_Fault) {
%(postacc_code)s;
}
if (fault == No_Fault) {
%(op_wb)s;
}
return fault;
}
}};
def template MiscMemAccExecute {{
Fault %(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
{
Addr EA;
Fault fault = No_Fault;
%(fp_enable_check)s;
%(op_decl)s;
%(op_rd)s;
EA = xc->getEA();
if (fault == No_Fault) {
%(code)s;
}
return No_Fault;
}
}};
def template MiscExecute {{
Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData) const
{
@ -292,11 +369,11 @@ def template PrefetchExecute {{
%(fp_enable_check)s;
%(op_decl)s;
%(op_nonmem_rd)s;
%(op_rd)s;
%(ea_code)s;
if (fault == No_Fault) {
xc->prefetch(EA, memAccessFlags);
%(memacc_code)s;
}
return No_Fault;
@ -332,8 +409,7 @@ def template LoadPrefetchCheckDecode {{
let {{
def LoadStoreBase(name, Name, ea_code, memacc_code, postacc_code = '',
base_class = 'MemoryDisp32', flags = [],
decode_template = BasicDecode,
exec_template = LoadStoreExecute):
decode_template = BasicDecode, exec_template_base = ''):
# Segregate flags into instruction flags (handled by InstObjParams)
# and memory access flags (handled here).
@ -380,19 +456,24 @@ def LoadStoreBase(name, Name, ea_code, memacc_code, postacc_code = '',
iop.constructor += s
memacc_iop.constructor += s
# select templates
memAccExecTemplate = eval(exec_template_base + 'MemAccExecute')
fullExecTemplate = eval(exec_template_base + 'Execute')
# (header_output, decoder_output, decode_block, exec_output)
return (LoadStoreDeclare.subst(iop), LoadStoreConstructor.subst(iop),
decode_template.subst(iop),
EACompExecute.subst(ea_iop)
+ MemAccExecute.subst(memacc_iop)
+ exec_template.subst(iop))
+ memAccExecTemplate.subst(memacc_iop)
+ fullExecTemplate.subst(iop))
}};
def format LoadOrNop(ea_code, memacc_code, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name, ea_code, memacc_code, flags = flags,
decode_template = LoadNopCheckDecode)
decode_template = LoadNopCheckDecode,
exec_template_base = 'Load')
}};
@ -401,7 +482,8 @@ def format LoadOrPrefetch(ea_code, memacc_code, *pf_flags) {{
# declare the load instruction object and generate the decode block
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name, ea_code, memacc_code,
decode_template = LoadPrefetchCheckDecode)
decode_template = LoadPrefetchCheckDecode,
exec_template_base = 'Load')
# Declare the prefetch instruction object.
@ -409,8 +491,9 @@ def format LoadOrPrefetch(ea_code, memacc_code, *pf_flags) {{
pf_flags = list(pf_flags) + ['IsMemRef', 'IsLoad', 'IsDataPrefetch', 'MemReadOp', 'NO_FAULT']
(pf_header_output, pf_decoder_output, _, pf_exec_output) = \
LoadStoreBase(name, Name + 'Prefetch', ea_code, '',
flags = pf_flags, exec_template = PrefetchExecute)
LoadStoreBase(name, Name + 'Prefetch', ea_code,
'xc->prefetch(EA, memAccessFlags);',
flags = pf_flags, exec_template_base = 'Misc')
header_output += pf_header_output
decoder_output += pf_decoder_output
@ -420,14 +503,15 @@ def format LoadOrPrefetch(ea_code, memacc_code, *pf_flags) {{
def format Store(ea_code, memacc_code, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name, ea_code, memacc_code, flags = flags)
LoadStoreBase(name, Name, ea_code, memacc_code, flags = flags,
exec_template_base = 'Store')
}};
def format StoreCond(ea_code, memacc_code, postacc_code, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name, ea_code, memacc_code, postacc_code,
flags = flags)
flags = flags, exec_template_base = 'Store')
}};
@ -435,7 +519,7 @@ def format StoreCond(ea_code, memacc_code, postacc_code, *flags) {{
def format MiscPrefetch(ea_code, memacc_code, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name, ea_code, memacc_code, flags = flags,
base_class = 'MemoryNoDisp')
base_class = 'MemoryNoDisp', exec_template_base = 'Misc')
}};

13
arch/alpha/isa/pal.isa
View file

@ -195,10 +195,19 @@ output decoder {{
}
}};
def format HwLoadStore(ea_code, memacc_code, class_ext, *flags) {{
def format HwLoad(ea_code, memacc_code, class_ext, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name + class_ext, ea_code, memacc_code,
flags = flags, base_class = 'HwLoadStore')
flags = flags, base_class = 'HwLoadStore',
exec_template_base = 'Load')
}};
def format HwStore(ea_code, memacc_code, class_ext, *flags) {{
(header_output, decoder_output, decode_block, exec_output) = \
LoadStoreBase(name, Name + class_ext, ea_code, memacc_code,
flags = flags, base_class = 'HwLoadStore',
exec_template_base = 'Store')
}};

183
arch/isa_parser.py
View file

@ -868,16 +868,21 @@ def fixPythonIndentation(s):
return s
# Error handler. Just call exit. Output formatted to work under
# Emacs compile-mode.
# Emacs compile-mode. This function should be called when errors due
# to user input are detected (as opposed to parser bugs).
def error(lineno, string):
spaces = ""
for (filename, line) in fileNameStack[0:-1]:
print spaces + "In file included from " + filename
spaces += " "
# Uncomment the following line to get a Python stack backtrace for
# these errors too. Can be handy when trying to debug the parser.
# traceback.print_exc()
sys.exit(spaces + "%s:%d: %s" % (fileNameStack[-1][0], lineno, string))
# Like error(), but include a Python stack backtrace (for processing
# Python exceptions).
# Python exceptions). This function should be called for errors that
# appear to be bugs in the parser itself.
def error_bt(lineno, string):
traceback.print_exc()
print >> sys.stderr, "%s:%d: %s" % (input_filename, lineno, string)
@ -1220,30 +1225,19 @@ class MemOperandTraits(OperandTraits):
# to avoid 'uninitialized variable' errors from the compiler.
# Declare memory data variable.
c = '%s %s = 0;\n' % (type, op_desc.base_name)
# Declare var to hold memory access flags.
c += 'unsigned %s_flags = memAccessFlags;\n' % op_desc.base_name
# If this operand is a dest (i.e., it's a store operation),
# then we need to declare a variable for the write result code
# as well.
if op_desc.is_dest:
c += 'uint64_t %s_write_result = 0;\n' % op_desc.base_name
return c
def makeRead(self, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
eff_type = 'uint%d_t' % size
return 'fault = xc->read(EA, (%s&)%s, %s_flags);\n' \
% (eff_type, op_desc.base_name, op_desc.base_name)
return ''
def makeWrite(self, op_desc):
return ''
# Return the memory access size *in bits*, suitable for
# forming a type via "uint%d_t". Divide by 8 if you want bytes.
def makeAccSize(self, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
eff_type = 'uint%d_t' % size
wb = 'fault = xc->write((%s&)%s, EA, %s_flags, &%s_write_result);\n' \
% (eff_type, op_desc.base_name, op_desc.base_name,
op_desc.base_name)
wb += 'if (traceData) { traceData->setData(%s); }' % \
op_desc.base_name
return wb
return size
class NPCOperandTraits(OperandTraits):
def makeConstructor(self, op_desc):
@ -1321,6 +1315,11 @@ class OperandDescriptor:
else:
self.eff_ext = self.traits.dflt_ext
# note that mem_acc_size is undefined for non-mem operands...
# template must be careful not to use it if it doesn't apply.
if self.traits.isMem():
self.mem_acc_size = self.traits.makeAccSize(self)
# Finalize additional fields (primarily code fields). This step
# is done separately since some of these fields may depend on the
# register index enumeration that hasn't been performed yet at the
@ -1340,10 +1339,73 @@ class OperandDescriptor:
else:
self.op_wb = ''
class OperandDescriptorList:
def __init__(self):
# Find all the operands in the given code block. Returns an operand
# descriptor list (instance of class OperandDescriptorList).
def __init__(self, code):
self.items = []
self.bases = {}
# delete comments so we don't match on reg specifiers inside
code = commentRE.sub('', code)
# search for operands
next_pos = 0
while 1:
match = operandsRE.search(code, next_pos)
if not match:
# no more matches: we're done
break
op = match.groups()
# regexp groups are operand full name, base, and extension
(op_full, op_base, op_ext) = op
# if the token following the operand is an assignment, this is
# a destination (LHS), else it's a source (RHS)
is_dest = (assignRE.match(code, match.end()) != None)
is_src = not is_dest
# see if we've already seen this one
op_desc = self.find_base(op_base)
if op_desc:
if op_desc.ext != op_ext:
error(0, 'Inconsistent extensions for operand %s' % \
op_base)
op_desc.is_src = op_desc.is_src or is_src
op_desc.is_dest = op_desc.is_dest or is_dest
else:
# new operand: create new descriptor
op_desc = OperandDescriptor(op_full, op_base, op_ext,
is_src, is_dest)
self.append(op_desc)
# start next search after end of current match
next_pos = match.end()
self.sort()
# enumerate source & dest register operands... used in building
# constructor later
self.numSrcRegs = 0
self.numDestRegs = 0
self.numFPDestRegs = 0
self.numIntDestRegs = 0
self.memOperand = None
for op_desc in self.items:
if op_desc.traits.isReg():
if op_desc.is_src:
op_desc.src_reg_idx = self.numSrcRegs
self.numSrcRegs += 1
if op_desc.is_dest:
op_desc.dest_reg_idx = self.numDestRegs
self.numDestRegs += 1
if op_desc.traits.isFloatReg():
self.numFPDestRegs += 1
elif op_desc.traits.isIntReg():
self.numIntDestRegs += 1
elif op_desc.traits.isMem():
if self.memOperand:
error(0, "Code block has more than one memory operand.")
self.memOperand = op_desc
# now make a final pass to finalize op_desc fields that may depend
# on the register enumeration
for op_desc in self.items:
op_desc.finalize()
def __len__(self):
return len(self.items)
@ -1398,69 +1460,6 @@ commentRE = re.compile(r'//.*\n')
# (used in findOperands())
assignRE = re.compile(r'\s*=(?!=)', re.MULTILINE)
#
# Find all the operands in the given code block. Returns an operand
# descriptor list (instance of class OperandDescriptorList).
#
def findOperands(code):
operands = OperandDescriptorList()
# delete comments so we don't accidentally match on reg specifiers inside
code = commentRE.sub('', code)
# search for operands
next_pos = 0
while 1:
match = operandsRE.search(code, next_pos)
if not match:
# no more matches: we're done
break
op = match.groups()
# regexp groups are operand full name, base, and extension
(op_full, op_base, op_ext) = op
# if the token following the operand is an assignment, this is
# a destination (LHS), else it's a source (RHS)
is_dest = (assignRE.match(code, match.end()) != None)
is_src = not is_dest
# see if we've already seen this one
op_desc = operands.find_base(op_base)
if op_desc:
if op_desc.ext != op_ext:
error(0, 'Inconsistent extensions for operand %s' % op_base)
op_desc.is_src = op_desc.is_src or is_src
op_desc.is_dest = op_desc.is_dest or is_dest
else:
# new operand: create new descriptor
op_desc = OperandDescriptor(op_full, op_base, op_ext,
is_src, is_dest)
operands.append(op_desc)
# start next search after end of current match
next_pos = match.end()
operands.sort()
# enumerate source & dest register operands... used in building
# constructor later
srcRegs = 0
destRegs = 0
operands.numFPDestRegs = 0
operands.numIntDestRegs = 0
for op_desc in operands:
if op_desc.traits.isReg():
if op_desc.is_src:
op_desc.src_reg_idx = srcRegs
srcRegs += 1
if op_desc.is_dest:
op_desc.dest_reg_idx = destRegs
destRegs += 1
if op_desc.traits.isFloatReg():
operands.numFPDestRegs += 1
elif op_desc.traits.isIntReg():
operands.numIntDestRegs += 1
operands.numSrcRegs = srcRegs
operands.numDestRegs = destRegs
# now make a final pass to finalize op_desc fields that may depend
# on the register enumeration
for op_desc in operands:
op_desc.finalize()
return operands
# Munge operand names in code string to make legal C++ variable names.
# This means getting rid of the type extension if any.
# (Will match base_name attribute of OperandDescriptor object.)
@ -1489,7 +1488,7 @@ def makeFlagConstructor(flag_list):
class CodeBlock:
def __init__(self, code):
self.orig_code = code
self.operands = findOperands(code)
self.operands = OperandDescriptorList(code)
self.code = substMungedOpNames(substBitOps(code))
self.constructor = self.operands.concatAttrStrings('constructor')
self.constructor += \
@ -1503,22 +1502,14 @@ class CodeBlock:
self.op_decl = self.operands.concatAttrStrings('op_decl')
is_mem = lambda op: op.traits.isMem()
not_mem = lambda op: not op.traits.isMem()
self.op_rd = self.operands.concatAttrStrings('op_rd')
self.op_wb = self.operands.concatAttrStrings('op_wb')
self.op_mem_rd = \
self.operands.concatSomeAttrStrings(is_mem, 'op_rd')
self.op_mem_wb = \
self.operands.concatSomeAttrStrings(is_mem, 'op_wb')
self.op_nonmem_rd = \
self.operands.concatSomeAttrStrings(not_mem, 'op_rd')
self.op_nonmem_wb = \
self.operands.concatSomeAttrStrings(not_mem, 'op_wb')
self.flags = self.operands.concatAttrLists('flags')
if self.operands.memOperand:
self.mem_acc_size = self.operands.memOperand.mem_acc_size
# Make a basic guess on the operand class (function unit type).
# These are good enough for most cases, and will be overridden
# later otherwise.