## adl-gen-delay.pkg
#
# Generate the <architecture>DelaySlots generic.
# This package contains information about delay slot filling
### "We are not interested in the fact
### that the brain has the consistency
### of cold porridge."
###
### -- Alan Turing
stipulate
package ard = architecture_description; # architecture_description is from src/lib/compiler/back/low/tools/arch/architecture-description.pkg package mst = adl_symboltable; # adl_symboltable is from src/lib/compiler/back/low/tools/arch/adl-symboltable.pkg package raw = adl_raw_syntax_form; # adl_raw_syntax_form is from src/lib/compiler/back/low/tools/adl-syntax/adl-raw-syntax-form.pkg package rsj = adl_raw_syntax_junk; # adl_raw_syntax_junk is from src/lib/compiler/back/low/tools/adl-syntax/adl-raw-syntax-junk.pkgherein
package MDGenDelaySlots
: (weak) Make_Sourcecode_For_Package # Make_Sourcecode_For_Package is from src/lib/compiler/back/low/tools/arch/make-sourcecode-for-package.api {
include package raw;
include package rsj;
fun delay DELAY_NONE => ID "D_NONE";
delay DELAY_ERROR => ID "D_ERROR";
delay DELAY_ALWAYS => ID "D_ALWAYS";
delay DELAY_TAKEN => ID "D_TAKEN";
delay DELAY_NONTAKEN => ID "D_FALLTHRU";
#
delay (DELAY_IF (BRANCHforwards, x, y)) => IF_EXPRESSION (ID "backward", delay y, delay x);
delay (DELAY_IF (BRANCHbackwards, x, y)) => IF_EXPRESSION (ID "backward", delay x, delay y);
end
also
fun flag FLAGoff => BOOLexp FALSE;
flag FLAGon => BOOLexp TRUE;
#
flag (FLAGid (id, TRUE, e)) => AND (ID id, e);
flag (FLAGid (id, FALSE, e)) => AND (APPLY("not", ID id), e);
end;
fun delay_slot_entry (nop, n, nOn, nOff)
=
RECORD_IN_EXPRESSION [ ("nop", nop), ("n", n), ("nOn", nOn), ("nOff", nOff) ];
default_delay_slot
=
delay_slot_entry (TRUE, FALSE, delay DELAY_ERROR, delay DELAY_NONE);
fun make_sourcecode_for_package architecture_description
=
ard::coder architecture_description "jmp/DelaySlots"
[ ard::make_generic architecture_description "DelaySlots" args sig_name str_body
]
where
# Name of the generic and its api:
#
str_name = ard::strname architecture_description "DelaySlots";
sig_name = "Delay_Slot_Properties";
instructions = ard::base_ops_of architecture_description; # The instruction set.
symboltable = mst::empty; # The symboltable.
# Arguments to the generic:
#
args =
["package i: " + ard::strname architecture_description "INSTR",
"package p: Machcode_Universals",
" where I = I"
];
fun mk_fun (name, args, x, body, default)
=
FUN_DECL
[ FUN
( name,
[ CLAUSE
( [ RECORD_PATTERN ( map (\\ x = (x, IDPAT x)) args,
NULL,
FALSE
)
],
LET_EXPRESSION
( [ FUN_DECL
[ FUN
( name,
[ CLAUSE ( [ IDPAT x ],
NULL,
CASE_EXPRESSION
( ID x,
body @ [ CLAUSE ([WILDCARD_PATTERN], NULL, default) ]
)
)
]
)
]
],
[APPLY_EXPRESSION (ID name, ID x)]
)
)
]
)
];
# Function to extract the properties about delay slot:
#
delay_slot
=
mk_fun ("delay_slot",["instruction", "backward"], "instruction", g instructions, default_delay_slot)
where
fun mk_pattern cons
=
mst::cons_to_pattern { prefix="I", cons=cons };
fun g [] => [];
#
g (CONSTRUCTOR_DEF { delayslot=(_, DELAY_NONE), nop=FLAGoff, nullified=FLAGoff, ... } ! cbs)
=>
g cbs;
g ((c as CONSTRUCTOR_DEF { id, delayslot=(d1, d2), nop, nullified, ... } ) ! cbs)
=>
CLAUSE ( [mk_pattern c],
NULL,
delay_slot_entry (flag nop, flag nullified, delay d1, delay d2)) ! g cbs;
end;
end;
enable_delay_slot = dummy_fun "enableDelaySlot"; # Function to enable/disable a delay slot.
conflict = dummy_fun "conflict"; # Function to check whether two delay slots have conflicts.
# Function to check if a instruction is a delay slot candidate:
#
delay_slot_candidate
=
mk_fun ("delaySlotCandidate", ["jmp", "delaySlot"], "delaySlot", g instructions, TRUE)
where
fun g [] => [];
g ( CONSTRUCTOR_DEF { delayslot_candidate=>NULL, ... } ! cbs) => g cbs:
g ((c as CONSTRUCTOR_DEF { delayslot_candidate=>THE e, ... } ) ! cbs) => CLAUSE ([mst::cons_to_pattern { prefix="I", cons=c } ], NULL, e) ! g cbs;
end;
end;
set_target = dummy_fun "setTarget"; # Function to set the target of a branch.
# The generic:
#
str_body
=
[ @@@ [ "package i = I",
"enum delay_slot = D_NONE | D_ERROR | D_ALWAYS | D_TAKEN | D_FALLTHRU ",
""
],
ERRORfun str_name,
delay_slot,
enable_delay_slot,
conflict,
delay_slot_candidate,
set_target
];
end;
};
end; # stipulate