Merge pull request #1277 from YosysHQ/eddie/fix_1262

opt_expr -fine to now trim LSBs of $alu cells too
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Eddie Hung 2019-08-11 22:10:17 -07:00 committed by GitHub
commit ba1a428f55
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2 changed files with 209 additions and 86 deletions

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@ -641,7 +641,8 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
}
}
if (cell->type.in("$add", "$sub")) {
if (cell->type.in("$add", "$sub"))
{
RTLIL::SigSpec sig_a = assign_map(cell->getPort("\\A"));
RTLIL::SigSpec sig_b = assign_map(cell->getPort("\\B"));
RTLIL::SigSpec sig_y = cell->getPort("\\Y");
@ -665,6 +666,53 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
did_something = true;
}
}
if (cell->type == "$alu")
{
RTLIL::SigSpec sig_a = assign_map(cell->getPort("\\A"));
RTLIL::SigSpec sig_b = assign_map(cell->getPort("\\B"));
RTLIL::SigBit sig_ci = assign_map(cell->getPort("\\CI"));
RTLIL::SigBit sig_bi = assign_map(cell->getPort("\\BI"));
RTLIL::SigSpec sig_x = cell->getPort("\\X");
RTLIL::SigSpec sig_y = cell->getPort("\\Y");
RTLIL::SigSpec sig_co = cell->getPort("\\CO");
if (sig_ci.wire || sig_bi.wire)
goto next_cell;
bool sub = (sig_ci == State::S1 && sig_bi == State::S1);
// If not a subtraction, yet there is a carry or B is inverted
// then no optimisation is possible as carry will not be constant
if (!sub && (sig_ci != State::S0 || sig_bi != State::S0))
goto next_cell;
int i;
for (i = 0; i < GetSize(sig_y); i++) {
if (sig_b.at(i, State::Sx) == State::S0 && sig_a.at(i, State::Sx) != State::Sx) {
module->connect(sig_x[i], sub ? module->Not(NEW_ID, sig_a[i]).as_bit() : sig_a[i]);
module->connect(sig_y[i], sig_a[i]);
module->connect(sig_co[i], sub ? State::S1 : State::S0);
}
else if (!sub && sig_a.at(i, State::Sx) == State::S0 && sig_b.at(i, State::Sx) != State::Sx) {
module->connect(sig_x[i], sig_b[i]);
module->connect(sig_y[i], sig_b[i]);
module->connect(sig_co[i], State::S0);
}
else
break;
}
if (i > 0) {
cover("opt.opt_expr.fine.$alu");
cell->setPort("\\A", sig_a.extract_end(i));
cell->setPort("\\B", sig_b.extract_end(i));
cell->setPort("\\X", sig_x.extract_end(i));
cell->setPort("\\Y", sig_y.extract_end(i));
cell->setPort("\\CO", sig_co.extract_end(i));
cell->fixup_parameters();
did_something = true;
}
}
}
if (cell->type.in("$reduce_xor", "$reduce_xnor", "$shift", "$shiftx", "$shl", "$shr", "$sshl", "$sshr",

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@ -5,144 +5,219 @@ module opt_expr_add_test(input [3:0] i, input [7:0] j, output [8:0] o);
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
equiv_opt -assert opt_expr -fine
design -load postopt
opt_expr -fine
wreduce
select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
design -stash gate
design -import gold -as gold
design -import gate -as gate
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
select -assert-count 1 t:$add r:A_WIDTH=5 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
##########
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_add_test(input [3:0] i, input [7:0] j, output [8:0] o);
assign o = (i << 4) + j;
endmodule
EOT
alumacc
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
design -reset
read_verilog <<EOT
module opt_expr_add_signed_test(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
assign o = (i << 4) + j;
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
equiv_opt -assert opt_expr -fine
design -load postopt
opt_expr -fine
wreduce
select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
design -stash gate
design -import gold -as gold
design -import gate -as gate
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
select -assert-count 1 t:$add r:A_WIDTH=5 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
##########
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_add_signed_test(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
assign o = (i << 4) + j;
endmodule
EOT
alumacc
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
design -reset
read_verilog <<EOT
module opt_expr_sub_test1(input [3:0] i, input [7:0] j, output [8:0] o);
assign o = j - (i << 4);
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
equiv_opt -assert opt_expr -fine
design -load postopt
opt_expr -fine
wreduce
select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
design -stash gate
design -import gold -as gold
design -import gate -as gate
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_sub_test1(input [3:0] i, input [7:0] j, output [8:0] o);
assign o = j - (i << 4);
endmodule
EOT
alumacc
equiv_opt -assert opt_expr -fine
design -load postopt
dump
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
design -reset
read_verilog <<EOT
module opt_expr_sub_signed_test1(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
assign o = j - (i << 4);
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
equiv_opt -assert opt_expr -fine
design -load postopt
opt_expr -fine
wreduce
select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
design -stash gate
design -import gold -as gold
design -import gate -as gate
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_sub_signed_test1(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
assign o = j - (i << 4);
endmodule
EOT
alumacc
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=5 r:Y_WIDTH=5 %i %i %i
##########
design -reset
read_verilog <<EOT
module opt_expr_sub_test2(input [3:0] i, input [7:0] j, output [8:0] o);
assign o = (i << 4) - j;
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
equiv_opt -assert opt_expr -fine
design -load postopt
opt_expr -fine
wreduce
select -assert-count 1 t:$sub r:A_WIDTH=8 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
design -stash gate
design -import gold -as gold
design -import gate -as gate
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
select -assert-count 1 t:$sub r:A_WIDTH=9 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
##########
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_sub_test2(input [3:0] i, input [7:0] j, output [8:0] o);
assign o = (i << 4) - j;
endmodule
EOT
alumacc
opt_expr -fine
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=9 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
##########
design -reset
read_verilog <<EOT
module opt_expr_sub_test4(input [3:0] i, output [8:0] o);
assign o = 5'b00010 - i;
endmodule
EOT
hierarchy -auto-top
proc
design -save gold
opt_expr -fine
wreduce
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$sub r:A_WIDTH=2 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
design -stash gate
##########
design -import gold -as gold
design -import gate -as gate
# alumacc version of above
design -reset
read_verilog <<EOT
module opt_expr_sub_test4(input [3:0] i, output [8:0] o);
assign o = 5'b00010 - i;
endmodule
EOT
miter -equiv -flatten -make_assert -make_outputs gold gate miter
sat -verify -prove-asserts -show-ports miter
wreduce
alumacc
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=2 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
###########
design -reset
read_verilog -icells <<EOT
module opt_expr_alu_test_ci0_bi0(input [7:0] a, input [3:0] b, output [8:0] x, y, co);
\$alu #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(8), .B_WIDTH(8), .Y_WIDTH(9)) alu (.A(a), .B({b, 4'b0000}), .CI(1'b0), .BI(1'b0), .X(x), .Y(y), .CO(co));
endmodule
EOT
check
equiv_opt -assert opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
###########
design -reset
read_verilog -icells <<EOT
module opt_expr_alu_test_ci1_bi1(input [7:0] a, input [3:0] b, output [8:0] x, y, co);
\$alu #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(8), .B_WIDTH(8), .Y_WIDTH(9)) alu (.A(a), .B({b, 4'b0000}), .CI(1'b1), .BI(1'b1), .X(x), .Y(y), .CO(co));
endmodule
EOT
check
equiv_opt opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
###########
design -reset
read_verilog -icells <<EOT
module opt_expr_alu_test_ci0_bi1(input [7:0] a, input [3:0] b, output [8:0] x, y, co);
\$alu #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(8), .B_WIDTH(8), .Y_WIDTH(9)) alu (.A(a), .B({b, 4'b0000}), .CI(1'b0), .BI(1'b1), .X(x), .Y(y), .CO(co));
endmodule
EOT
check
equiv_opt opt_expr -fine
design -load postopt
select -assert-count 1 t:$alu r:A_WIDTH=8 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i