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Merge remote-tracking branch 'origin/eddie/peepopt_dffmuxext' into xc7dsp

This commit is contained in:
Eddie Hung 2019-09-11 13:37:11 -07:00
parent 0ebbecf833 bdb5e0f29c
commit c0f26c2da8
2 changed files with 116 additions and 27 deletions
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72
passes/pmgen/peepopt_dffmux.pmg
View File

@ -1,30 +1,48 @@
pattern dffmux
state <IdString> muxAB
state <IdString> cemuxAB rstmuxBA
state <SigSpec> sigD
match dff
select dff->type == $dff
select GetSize(port(dff, \D)) > 1
endmatch
match mux
select mux->type == $mux
select GetSize(port(mux, \Y)) > 1
match rstmux
select rstmux->type == $mux
select GetSize(port(rstmux, \Y)) > 1
index <SigSpec> port(rstmux, \Y) === port(dff, \D)
choice <IdString> BA {\B, \A}
select port(rstmux, BA).is_fully_const()
set rstmuxBA BA
optional
endmatch
code sigD
if (rstmux)
sigD = port(rstmux, rstmuxBA == \B ? \A : \B);
else
sigD = port(dff, \D);
endcode
match cemux
select cemux->type == $mux
select GetSize(port(cemux, \Y)) > 1
index <SigSpec> port(cemux, \Y) === sigD
choice <IdString> AB {\A, \B}
//select port(mux, AB)[GetSize(port(mux, \Y))-1].wire
index <SigSpec> port(mux, \Y) === port(dff, \D)
define <IdString> BA (AB == \A ? \B : \A)
index <SigSpec> port(mux, BA) === port(dff, \Q)
set muxAB AB
index <SigSpec> port(cemux, AB) === port(dff, \Q)
set cemuxAB AB
endmatch
code
SigSpec &D = mux->connections_.at(muxAB);
SigSpec &D = cemux->connections_.at(cemuxAB == \A ? \B : \A);
SigSpec &Q = dff->connections_.at(\Q);
Const rst;
if (rstmux)
rst = port(rstmux, rstmuxBA).as_const();
int width = GetSize(D);
SigSpec AB = port(mux, muxAB);
if (AB[width-1] == AB[width-2]) {
if (D[width-1] == D[width-2]) {
did_something = true;
SigBit sign = D[width-1];
@ -33,31 +51,31 @@ code
for (i = width-1; i >= 2; i--) {
if (!is_signed) {
module->connect(Q[i], sign);
if (D[i-1] != sign)
if (D[i-1] != sign || (rst.size() && rst[i-1] != rst[width-1]))
break;
}
else {
module->connect(Q[i], Q[i-1]);
if (D[i-2] != sign)
if (D[i-2] != sign || (rst.size() && rst[i-1] != rst[width-1]))
break;
}
}
mux->connections_.at(\A).remove(i, width-i);
mux->connections_.at(\B).remove(i, width-i);
mux->connections_.at(\Y).remove(i, width-i);
mux->fixup_parameters();
cemux->connections_.at(\A).remove(i, width-i);
cemux->connections_.at(\B).remove(i, width-i);
cemux->connections_.at(\Y).remove(i, width-i);
cemux->fixup_parameters();
dff->connections_.at(\D).remove(i, width-i);
dff->connections_.at(\Q).remove(i, width-i);
dff->fixup_parameters();
log("dffmux pattern in %s: dff=%s, mux=%s; removed top %d bits.\n", log_id(module), log_id(dff), log_id(mux), width-i);
log("dffcemux pattern in %s: dff=%s, cemux=%s; removed top %d bits.\n", log_id(module), log_id(dff), log_id(cemux), width-i);
accept;
}
else {
int count = 0;
for (int i = width-1; i >= 0; i--) {
if (AB[i].wire)
if (D[i].wire)
continue;
Wire *w = Q[i].wire;
auto it = w->attributes.find(\init);
@ -67,23 +85,23 @@ code
else
init = State::Sx;
if (init == State::Sx || init == AB[i].data) {
if (init == State::Sx || init == D[i].data) {
count++;
module->connect(Q[i], AB[i]);
mux->connections_.at(\A).remove(i);
mux->connections_.at(\B).remove(i);
mux->connections_.at(\Y).remove(i);
module->connect(Q[i], D[i]);
cemux->connections_.at(\A).remove(i);
cemux->connections_.at(\B).remove(i);
cemux->connections_.at(\Y).remove(i);
dff->connections_.at(\D).remove(i);
dff->connections_.at(\Q).remove(i);
}
}
if (count > 0) {
did_something = true;
mux->fixup_parameters();
cemux->fixup_parameters();
dff->fixup_parameters();
log("dffcemux pattern in %s: dff=%s, cemux=%s; removed %d constant bits.\n", log_id(module), log_id(dff), log_id(cemux), count);
}
log("dffmux pattern in %s: dff=%s, mux=%s; removed %d constant bits.\n", log_id(module), log_id(dff), log_id(mux), count);
accept;
}
endcode

71
tests/various/peepopt.ys
View File

@ -78,3 +78,74 @@ clean
select -assert-count 1 t:$dff r:WIDTH=2 %i
select -assert-count 1 t:$mux r:WIDTH=2 %i
select -assert-count 0 t:$dff t:$mux %% t:* %D
###################
design -reset
read_verilog <<EOT
module peepopt_dffmuxext_const(input clk, ce, input [1:0] i, output reg [5:0] o);
always @(posedge clk) if (ce) o <= {1'b0, i[1], 2'b1x, i[0], 1'bz};
endmodule
EOT
proc
equiv_opt -assert peepopt
design -load postopt
select -assert-count 1 t:$dff r:WIDTH=2 %i
select -assert-count 1 t:$mux r:WIDTH=2 %i
select -assert-count 0 t:$dff t:$mux %% t:* %D
###################
design -reset
read_verilog <<EOT
module peepopt_dffmuxext_const_init(input clk, ce, input [1:0] i, (* init=6'b0x00x1 *) output reg [5:0] o);
always @(posedge clk) if (ce) o <= {1'b0, i[1], 2'b1x, i[0], 1'bz};
endmodule
EOT
proc
equiv_opt -assert peepopt
design -load postopt
select -assert-count 1 t:$dff r:WIDTH=5 %i
select -assert-count 1 t:$mux r:WIDTH=5 %i
select -assert-count 0 t:$dff t:$mux %% t:* %D
####################
design -reset
read_verilog <<EOT
module peepopt_dffmuxext_unsigned_rst(input clk, ce, rst, input [1:0] i, output reg [3:0] o);
always @(posedge clk) if (rst) o <= 0; else if (ce) o <= i;
endmodule
EOT
proc
equiv_opt -assert peepopt
design -load postopt
wreduce
select -assert-count 1 t:$dff r:WIDTH=2 %i
select -assert-count 2 t:$mux
select -assert-count 2 t:$mux r:WIDTH=2 %i
select -assert-count 0 t:$dff t:$mux %% t:* %D
####################
design -reset
read_verilog <<EOT
module peepopt_dffmuxext_signed_rst(input clk, ce, rstn, input signed [1:0] i, output reg signed [3:0] o);
always @(posedge clk) begin
if (ce) o <= i;
if (!rstn) o <= 4'b1111;
end
endmodule
EOT
proc
equiv_opt -assert peepopt
design -load postopt
wreduce
select -assert-count 1 t:$dff r:WIDTH=2 %i
select -assert-count 2 t:$mux
select -assert-count 2 t:$mux r:WIDTH=2 %i
select -assert-count 0 t:$logic_not t:$dff t:$mux %% t:* %D