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-rw-r--r--README16
-rw-r--r--csim/load.c6
-rw-r--r--csim/sim.c16
-rw-r--r--sched/main.ml2
-rw-r--r--sched/netlist_printer.ml4
-rw-r--r--sched/simplify.ml214
-rw-r--r--tests/clockHMS.mj69
-rw-r--r--tests/nadder.mj12
8 files changed, 322 insertions, 17 deletions
diff --git a/README b/README
index ff55a2c..40734fa 100644
--- a/README
+++ b/README
@@ -6,6 +6,7 @@ Alex AUVOLAT (Info 2013)
Contents of the repository :
+----------------------------
sched/
A scheduler for netlists.
@@ -36,3 +37,18 @@ minijazz/
Documentation about the project.
+
+CONVENTION FOR BINARY VALUES
+----------------------------
+
+/!\ This convention is contrary to the one used in the example file nadder.mj
+ (Therefore I have modified that file...)
+
+The bit array [a_0 a_1 a_2 ... a_n-1] represents the decimal number :
+ a_0 + 2*a_1 + 4*a_2 + ... + 2^(n-1)*a_n-1
+
+When represented in binary, we write the bits in the order :
+ a_0 a_1 a_2 ... a_n-1
+
+/!\ BINARY NUMBERS ARE WRITTEN REVERSE !
+
diff --git a/csim/load.c b/csim/load.c
index a7e6cac..7971a71 100644
--- a/csim/load.c
+++ b/csim/load.c
@@ -35,10 +35,10 @@ t_value read_bool(FILE *stream, t_value *mask) {
void read_arg(FILE *stream, t_arg *dest) {
dest->mask = 0;
- if (fscanf(stream, "$") > 0) {
- dest->Val = read_bool(stream, &dest->mask);
+ if (fscanf(stream, "$%d ", &(dest->SrcVar))) {
+ // ok, value is read
} else {
- fscanf(stream, "%d ", &(dest->SrcVar));
+ dest->Val = read_bool(stream, &dest->mask);
}
}
diff --git a/csim/sim.c b/csim/sim.c
index 9b6906f..db3b711 100644
--- a/csim/sim.c
+++ b/csim/sim.c
@@ -55,7 +55,8 @@ t_machine *init_machine (t_program *p) {
void read_inputs(t_machine *m, FILE *stream) {
/* FORMAT :
For each input in the list, *in the order specified*,
- the binary value for that variable.
+ either '/' followed by the decimal value
+ or the binary value
*/
int i;
t_id var;
@@ -66,7 +67,12 @@ void read_inputs(t_machine *m, FILE *stream) {
for (i = 0; i < p->n_inputs; i++) {
var = p->inputs[i];
fscanf(stream, " ");
- m->var_values[var] = read_bool(stream, NULL);
+ if (fscanf(stream, "/%lu", &(m->var_values[var]))) {
+ // ok, value is read
+ } else {
+ m->var_values[var] = read_bool(stream, NULL);
+ }
+ m->var_values[var] &= p->vars[var].mask;
}
}
@@ -179,7 +185,7 @@ void machine_step(t_machine *m) {
if (e != 0) {
a = get_var(m, p->eqs[i].Ram.write_addr);
d = get_var(m, p->eqs[i].Ram.data);
- printf("Write ram %lx = %lx\n", a, d);
+ if (DEBUG) fprintf(stderr, "Write ram %lx = %lx\n", a, d);
m->mem_data[i].RamData[a] = d;
}
}
@@ -189,7 +195,7 @@ void machine_step(t_machine *m) {
void write_outputs(t_machine *m, FILE *stream) {
/* FORMAT :
For each output value, a line in the form
- var_name binary_value
+ var_name binary_value decimal_value
*/
int i;
t_id var;
@@ -205,7 +211,7 @@ void write_outputs(t_machine *m, FILE *stream) {
v >>= 1;
mask >>= 1;
}
- fprintf(stream, "\n");
+ fprintf(stream, "\t%ld\n", m->var_values[var]);
}
fprintf(stream, "\n");
}
diff --git a/sched/main.ml b/sched/main.ml
index 988d1ec..a2a4d3b 100644
--- a/sched/main.ml
+++ b/sched/main.ml
@@ -11,7 +11,7 @@ let compile filename =
let q = ref p in
begin try
- q := Scheduler.schedule p
+ q := (Simplify.simplify (Scheduler.schedule p))
with
| Scheduler.Combinational_cycle ->
Format.eprintf "The netlist has a combinatory cycle.@.";
diff --git a/sched/netlist_printer.ml b/sched/netlist_printer.ml
index b8cf385..746867f 100644
--- a/sched/netlist_printer.ml
+++ b/sched/netlist_printer.ml
@@ -133,8 +133,8 @@ let print_dumb_program oc p =
fprintf ff "%d\n" (List.length p.p_eqs);
(* write equations *)
let print_arg = function
- | Avar(k) -> fprintf ff " %d" (Hashtbl.find var_id k)
- | Aconst(n) -> fprintf ff " $";
+ | Avar(k) -> fprintf ff " $%d" (Hashtbl.find var_id k)
+ | Aconst(n) -> fprintf ff " ";
begin match n with
| VBit(x) -> fprintf ff "%d" (if x then 1 else 0)
| VBitArray(a) ->
diff --git a/sched/simplify.ml b/sched/simplify.ml
new file mode 100644
index 0000000..01f7c84
--- /dev/null
+++ b/sched/simplify.ml
@@ -0,0 +1,214 @@
+(* SIMPLIFICATION PASSES *)
+
+(*
+ Order of simplifications :
+ - cascade slices and selects
+ - simplify stupid things (a xor 0 = a, a and 0 = 0, etc.)
+ transform k = SLICE i i var into k = SELECT i var
+ - transform k = SELECT 0 var into k = var when var is also one bit
+ - look for variables with same equation, put the second to identity
+ - eliminate k' for each equation k' = k
+ - eliminate dead equations
+
+ These simplifications are run on a topologically sorted list of equations (see main.ml)
+*)
+
+open Netlist_ast
+
+module Sset = Set.Make(String)
+
+(* Simplify cascade slicing/selecting *)
+let cascade_slices p =
+ let slices = Hashtbl.create 42 in
+ let eqs_new = List.map
+ (fun (n, eq) -> (n, match eq with
+ | Eslice(u, v, Avar(x)) ->
+ let nu, nx =
+ if Hashtbl.mem slices x then begin
+ let ku, kx = Hashtbl.find slices x in
+ (ku + u, kx)
+ end else
+ (u, x)
+ in
+ Hashtbl.add slices n (nu, nx);
+ Eslice(nu, v, Avar(nx))
+ | Eselect(u, Avar(x)) ->
+ begin try
+ let ku, kx = Hashtbl.find slices x in
+ Eselect(ku + u, Avar(kx))
+ with
+ Not_found -> Eselect(u, Avar(x))
+ end
+ | _ -> eq))
+ p.p_eqs in
+ {
+ p_eqs = eqs_new;
+ p_inputs = p.p_inputs;
+ p_outputs = p.p_outputs;
+ p_vars = p.p_vars;
+ }
+
+(* Simplifies some trivial arithmetic possibilites :
+ a and 1 = a
+ a and 0 = 0
+ a or 1 = 1
+ a or 0 = a
+ a xor 0 = a
+ slice i i x = select i x
+*)
+let arith_simplify p =
+ {
+ p_eqs = List.map
+ (fun (n, eq) -> match eq with
+ | Ebinop(Or, Aconst(VBit(false)), x) -> (n, Earg(x))
+ | Ebinop(Or, Aconst(VBit(true)), x) -> (n, Earg(Aconst(VBit(true))))
+ | Ebinop(Or, x, Aconst(VBit(false))) -> (n, Earg(x))
+ | Ebinop(Or, x, Aconst(VBit(true))) -> (n, Earg(Aconst(VBit(true))))
+
+ | Ebinop(And, Aconst(VBit(false)), x) -> (n, Earg(Aconst(VBit(false))))
+ | Ebinop(And, Aconst(VBit(true)), x) -> (n, Earg(x))
+ | Ebinop(And, x, Aconst(VBit(false))) -> (n, Earg(Aconst(VBit(false))))
+ | Ebinop(And, x, Aconst(VBit(true))) -> (n, Earg(x))
+
+ | Ebinop(Xor, Aconst(VBit(false)), x) -> (n, Earg(x))
+ | Ebinop(Xor, x, Aconst(VBit(false))) -> (n, Earg(x))
+
+ | Eslice(i, j, k) when i = j ->
+ (n, Eselect(i, k))
+
+ | _ -> (n, eq))
+ p.p_eqs;
+ p_inputs = p.p_inputs;
+ p_outputs = p.p_outputs;
+ p_vars = p.p_vars;
+ }
+
+(* if x is one bit, then :
+ select 0 x = x
+*)
+let select_to_id p =
+ {
+ p_eqs = List.map
+ (fun (n, eq) -> match eq with
+ | Eselect(0, Avar(id)) when
+ Env.find id p.p_vars = TBit || Env.find id p.p_vars = TBitArray(1) ->
+ (n, Earg(Avar(id)))
+ | _ -> (n, eq))
+ p.p_eqs;
+ p_inputs = p.p_inputs;
+ p_outputs = p.p_outputs;
+ p_vars = p.p_vars;
+ }
+
+(*
+ If a = eqn(v1, v2, ...) and b = eqn(v1, v2, ...) <- the same equation
+ then say b = a
+*)
+let same_eq_simplify p =
+ let id_outputs =
+ (List.fold_left (fun x k -> Sset.add k x) Sset.empty p.p_outputs) in
+ let eq_map = Hashtbl.create 42 in
+ List.iter
+ (fun (n, eq) -> if Sset.mem n id_outputs then
+ Hashtbl.add eq_map eq n)
+ p.p_eqs;
+ let simplify_eq (n, eq) =
+ if Sset.mem n id_outputs then
+ (n, eq)
+ else if Hashtbl.mem eq_map eq then
+ (n, Earg(Avar(Hashtbl.find eq_map eq)))
+ else begin
+ Hashtbl.add eq_map eq n;
+ (n, eq)
+ end
+ in
+ let eq2 = List.map simplify_eq p.p_eqs in
+ {
+ p_eqs = eq2;
+ p_inputs = p.p_inputs;
+ p_outputs = p.p_outputs;
+ p_vars = p.p_vars;
+ }
+
+
+(* Replace one specific variable by another argument in the arguments of all equations
+ (possibly a constant, possibly another variable)
+*)
+let eliminate_var var rep p =
+ let rep_arg = function
+ | Avar(i) when i = var -> rep
+ | k -> k
+ in
+ let rep_eqs = List.map
+ (fun (n, eq) -> (n, match eq with
+ | Earg(a) -> Earg(rep_arg a)
+ | Ereg(i) when i = var ->
+ begin match rep with
+ | Avar(j) -> Ereg(j)
+ | Aconst(k) -> Earg(Aconst(k))
+ end
+ | Ereg(j) -> Ereg(j)
+ | Enot(a) -> Enot(rep_arg a)
+ | Ebinop(o, a, b) -> Ebinop(o, rep_arg a, rep_arg b)
+ | Emux(a, b, c) -> Emux(rep_arg a, rep_arg b, rep_arg c)
+ | Erom(u, v, a) -> Erom(u, v, rep_arg a)
+ | Eram(u, v, a, b, c, d) -> Eram(u, v, rep_arg a, rep_arg b, rep_arg c, rep_arg d)
+ | Econcat(a, b) -> Econcat(rep_arg a, rep_arg b)
+ | Eslice(u, v, a) -> Eslice(u, v, rep_arg a)
+ | Eselect(u, a) -> Eselect(u, rep_arg a)
+ ))
+ p.p_eqs in
+ {
+ p_eqs = List.fold_left
+ (fun x (n, eq) ->
+ if n = var then x else (n, eq)::x)
+ [] rep_eqs;
+ p_inputs = p.p_inputs;
+ p_outputs = p.p_outputs;
+ p_vars = Env.remove var p.p_vars;
+ }
+
+(* Remove all equations of type :
+ a = b
+ a = const
+ (except if a is an output variable)
+*)
+let rec eliminate_id p =
+ let id_outputs =
+ (List.fold_left (fun x k -> Sset.add k x) Sset.empty p.p_outputs) in
+
+ let rep =
+ List.fold_left
+ (fun x (n, eq) ->
+ if x = None && (not (Sset.mem n id_outputs)) then
+ match eq with
+ | Earg(rarg) ->
+ Some(n, rarg)
+ | _ -> None
+ else
+ x)
+ None p.p_eqs in
+ match rep with
+ | None -> p, false
+ | Some(n, rep) -> fst (eliminate_id (eliminate_var n rep p)), true
+
+
+(* Eliminate dead equations *)
+let eliminate_dead p =
+ p, false (* TODO *)
+ (* a bit like a topological sort... *)
+
+
+(* Apply all the simplification passes,
+ in the order given in the header of this file
+*)
+let rec simplify p =
+ let p1 = cascade_slices p in
+ let p2 = arith_simplify p1 in
+ let p3 = select_to_id p2 in
+ let p4 = same_eq_simplify p3 in
+ let p5, use5 = eliminate_id p4 in
+ let p6, use6 = eliminate_dead p5 in
+ let pp = p6 in
+ if use5 || use6 then simplify pp else pp
+
diff --git a/tests/clockHMS.mj b/tests/clockHMS.mj
new file mode 100644
index 0000000..27f96ea
--- /dev/null
+++ b/tests/clockHMS.mj
@@ -0,0 +1,69 @@
+repeat<n>(a) = (x:[n]) where
+ if n = 1 then
+ x = a
+ else
+ if n - (2 * (n / 2)) = 1 then
+ u = repeat<n/2>(a);
+ x = a . u . u
+ else
+ u = repeat<n/2>(a);
+ x = u . u
+ end if
+ end if
+end where
+
+fulladder(a,b,c) = (s, r) where
+ s = (a ^ b) ^ c;
+ r = (a & b) + ((a ^ b) & c);
+end where
+
+adder<n>(a:[n], b:[n], c_in) = (o:[n], c_out) where
+ if n = 0 then
+ o = [];
+ c_out = 0
+ else
+ (s_n, c_n1) = fulladder(a[0], b[0], c_in);
+ (s_n1, c_out) = adder<n-1>(a[1..], b[1..], c_n1);
+ o = s_n . s_n1
+ end if
+end where
+
+equal<n, m>(a:[n]) = (eq) where
+ if n = 0 then
+ eq = 1
+ else
+ if m - (2 * (m / 2)) = 1 then
+ eq = a[0] & equal<n-1, m/2>(a[1..]);
+ else
+ eq = (not a[0]) & equal<n-1, m/2>(a[1..]);
+ end if
+ end if
+end where
+
+reg_n<n>(a:[n]) = (r:[n]) where
+ if n = 0 then
+ r = []
+ else
+ r = (reg a[0]) . (reg_n<n-1>(r[1..]))
+ end if
+end where
+
+and_each<n>(a, b:[n]) = (o:[n]) where
+ if n = 0 then
+ o = []
+ else
+ o = (b[0] and a) . and_each<n-1>(a, b[1..])
+ end if
+end where
+
+count_mod<n, m>(in:[n]) = (out:[n]) where
+ neq = not (equal<n, m>(in));
+ (incr, carry) = adder<n>(in, 1 . repeat<n-1>(0), 0);
+ out = and_each<n>(neq, incr)
+end where
+
+main() = (ret:[2],out:[2]) where
+ out = count_mod<2, 3>(ret);
+ ret = reg_n<2>(out)
+end where
+
diff --git a/tests/nadder.mj b/tests/nadder.mj
index 0c95386..b75a83c 100644
--- a/tests/nadder.mj
+++ b/tests/nadder.mj
@@ -6,14 +6,14 @@ end where
adder<n>(a:[n], b:[n], c_in) = (o:[n], c_out) where
if n = 0 then
o = [];
- c_out = 0
+ c_out = c_in
else
- (s_n1, c_n1) = adder<n-1>(a[1..], b[1..], c_in);
- (s_n, c_out) = fulladder(a[0], b[0], c_n1);
+ (s_n, c_n1) = fulladder(a[0], b[0], c_in);
+ (s_n1, c_out) = adder<n-1>(a[1..], b[1..], c_n1);
o = s_n . s_n1
end if
end where
-main(a, b) = (o, c) where
- (o, c) = adder<1>(a,b,0)
-end where \ No newline at end of file
+main(a:[4], b:[4]) = (o:[4], c) where
+ (o, c) = adder<4>(a,b,0)
+end where
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-21 17:24:45 +0000