From: Clifford Wolf Date: Sat, 30 Aug 2014 13:12:39 +0000 (+0200) Subject: Replaced $__alu CO/CS outputs with full-width CO output X-Git-Tag: yosys-0.4~198 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=eb571cba6a8a2a53b179578d07798517addac7c0;p=yosys.git Replaced $__alu CO/CS outputs with full-width CO output --- diff --git a/techlibs/common/techmap.v b/techlibs/common/techmap.v index 1486b801e..452b64b8f 100644 --- a/techlibs/common/techmap.v +++ b/techlibs/common/techmap.v @@ -251,19 +251,18 @@ endmodule // ALU Infrastructure // -------------------------------------------------------- -module \$__alu_ripple (A, B, CI, X, Y, CO, CS); +module \$__alu_ripple (A, B, CI, X, Y, CO); parameter WIDTH = 1; input [WIDTH-1:0] A, B; output [WIDTH-1:0] X, Y; input CI; - output CO, CS; + output [WIDTH-1:0] CO; wire [WIDTH:0] carry; assign carry[0] = CI; - assign CO = carry[WIDTH]; - assign CS = carry[WIDTH-1]; + assign CO = carry[WIDTH:1]; genvar i; generate @@ -291,7 +290,7 @@ module \$__lcu (P, G, CI, CO); input [WIDTH-1:0] P, G; input CI; - output reg [WIDTH:0] CO; + output [WIDTH-1:0] CO; integer i, j; reg [WIDTH-1:0] p, g; @@ -326,23 +325,20 @@ module \$__lcu (P, G, CI, CO); end end - assign CO = {g, CI}; + assign CO = g; endmodule -module \$__alu_lookahead (A, B, CI, X, Y, CO, CS); +module \$__alu_lookahead (A, B, CI, X, Y, CO); parameter WIDTH = 1; input [WIDTH-1:0] A, B; output [WIDTH-1:0] X, Y; input CI; - output CO, CS; + output [WIDTH-1:0] CO; wire [WIDTH-1:0] P, G; - wire [WIDTH:0] C; - - assign CO = C[WIDTH]; - assign CS = C[WIDTH-1]; + wire [WIDTH:0] carry; genvar i; generate @@ -354,15 +350,16 @@ module \$__alu_lookahead (A, B, CI, X, Y, CO, CS); \$_XOR_ gate2 ( .A(a), .B(b), .Y(p) ); \$_XOR_ gate3 ( .A(p), .B(c), .Y(y) ); - assign a = A[i], b = B[i], c = C[i]; + assign a = A[i], b = B[i], c = carry[i]; assign P[i] = p, G[i] = g, X[i] = p, Y[i] = y; end endgenerate - \$__lcu #(.WIDTH(WIDTH)) lcu (.P(P), .G(G), .CI(CI), .CO(C)); + \$__lcu #(.WIDTH(WIDTH)) lcu (.P(P), .G(G), .CI(CI), .CO(CO)); + assign carry = {CO, CI}; endmodule -module \$__alu (A, B, CI, BI, X, Y, CO, CS); +module \$__alu (A, B, CI, BI, X, Y, CO); parameter A_SIGNED = 0; parameter B_SIGNED = 0; parameter A_WIDTH = 1; @@ -375,19 +372,19 @@ module \$__alu (A, B, CI, BI, X, Y, CO, CS); // carry in, sub, carry out, carry sign input CI, BI; - output CO, CS; + output [Y_WIDTH-1:0] CO; wire [Y_WIDTH-1:0] A_buf, B_buf; \$pos #(.A_SIGNED(A_SIGNED), .A_WIDTH(A_WIDTH), .Y_WIDTH(Y_WIDTH)) A_conv (.A(A), .Y(A_buf)); \$pos #(.A_SIGNED(B_SIGNED), .A_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) B_conv (.A(B), .Y(B_buf)); `ifdef ALU_RIPPLE - \$__alu_ripple #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO), .CS(CS)); + \$__alu_ripple #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO)); `else if (Y_WIDTH <= 4) begin - \$__alu_ripple #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO), .CS(CS)); + \$__alu_ripple #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO)); end else begin - \$__alu_lookahead #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO), .CS(CS)); + \$__alu_lookahead #(.WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A_buf), .B(BI ? ~B_buf : B_buf), .CI(CI), .X(X), .Y(Y), .CO(CO)); end `endif endmodule @@ -397,7 +394,7 @@ endmodule // ALU Cell Types: Compare, Add, Subtract // -------------------------------------------------------- -`define ALU_COMMONS(_width, _ci, _bi) """ +`define ALU_COMMONS(_width, _sub) """ parameter A_SIGNED = 0; parameter B_SIGNED = 0; parameter A_WIDTH = 1; @@ -410,8 +407,8 @@ endmodule input [B_WIDTH-1:0] B; output [Y_WIDTH-1:0] Y; - wire alu_co, alu_cs; - wire [WIDTH-1:0] alu_x, alu_y; + wire [WIDTH-1:0] alu_x, alu_y, alu_co; + wire [WIDTH:0] carry = {alu_co, |_sub}; \$__alu #( .A_SIGNED(A_SIGNED), @@ -422,41 +419,40 @@ endmodule ) alu ( .A(A), .B(B), - .CI(_ci), - .BI(_bi), + .CI(|_sub), + .BI(|_sub), .X(alu_x), .Y(alu_y), - .CO(alu_co), - .CS(alu_cs) + .CO(alu_co) ); wire cf, of, zf, sf; - assign cf = !alu_co; - assign of = alu_co ^ alu_cs; + assign cf = !carry[WIDTH]; + assign of = carry[WIDTH] ^ carry[WIDTH-1]; assign sf = alu_y[WIDTH-1]; """ module \$lt (A, B, Y); wire [1023:0] _TECHMAP_DO_ = "RECURSION; opt_const -mux_undef -mux_bool -fine;;;"; - `ALU_COMMONS(`MAX(A_WIDTH, B_WIDTH), 1, 1) + `ALU_COMMONS(`MAX(A_WIDTH, B_WIDTH), 1) assign Y = A_SIGNED && B_SIGNED ? of != sf : cf; endmodule module \$le (A, B, Y); wire [1023:0] _TECHMAP_DO_ = "RECURSION; opt_const -mux_undef -mux_bool -fine;;;"; - `ALU_COMMONS(`MAX(A_WIDTH, B_WIDTH), 1, 1) + `ALU_COMMONS(`MAX(A_WIDTH, B_WIDTH), 1) assign Y = &alu_x || (A_SIGNED && B_SIGNED ? of != sf : cf); endmodule module \$add (A, B, Y); wire [1023:0] _TECHMAP_DO_ = "RECURSION; opt_const -mux_undef -mux_bool -fine;;;"; - `ALU_COMMONS(Y_WIDTH, 0, 0) + `ALU_COMMONS(Y_WIDTH, 0) assign Y = alu_y; endmodule module \$sub (A, B, Y); wire [1023:0] _TECHMAP_DO_ = "RECURSION; opt_const -mux_undef -mux_bool -fine;;;"; - `ALU_COMMONS(Y_WIDTH, 1, 1) + `ALU_COMMONS(Y_WIDTH, 1) assign Y = alu_y; endmodule