diff options
Diffstat (limited to 'techlibs/common/cmp2lcu.v')
| -rw-r--r-- | techlibs/common/cmp2lcu.v | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/techlibs/common/cmp2lcu.v b/techlibs/common/cmp2lcu.v index e42f346d1..a221727e7 100644 --- a/techlibs/common/cmp2lcu.v +++ b/techlibs/common/cmp2lcu.v @@ -12,8 +12,11 @@ parameter A_WIDTH = 0; parameter B_WIDTH = 0; parameter Y_WIDTH = 0; +(* force_downto *) input [A_WIDTH-1:0] A; +(* force_downto *) input [B_WIDTH-1:0] B; +(* force_downto *) output [Y_WIDTH-1:0] Y; parameter _TECHMAP_CELLTYPE_ = ""; @@ -32,7 +35,9 @@ generate else begin // Perform sign extension on A and B localparam WIDTH = A_WIDTH > B_WIDTH ? A_WIDTH : B_WIDTH; + (* force_downto *) wire [WIDTH-1:0] AA = {{(WIDTH-A_WIDTH){A_SIGNED ? A[A_WIDTH-1] : 1'b0}}, A}; + (* force_downto *) wire [WIDTH-1:0] BB = {{(WIDTH-B_WIDTH){B_SIGNED ? B[B_WIDTH-1] : 1'b0}}, B}; // For $ge operation, start with the assumption that A and B are // equal (propagating this equality if A and B turn out to be so) @@ -54,9 +59,13 @@ parameter LCU_WIDTH = 1; parameter BUDGET = 0; parameter CI = 0; +(* force_downto *) input [AB_WIDTH-1:0] A; // A from original $gt/$ge +(* force_downto *) input [AB_WIDTH-1:0] B; // B from original $gt/$ge +(* force_downto *) input [LCU_WIDTH-1:0] P; // P of $lcu +(* force_downto *) input [LCU_WIDTH-1:0] G; // G of $lcu output Y; @@ -66,6 +75,7 @@ parameter [LCU_WIDTH-1:0] _TECHMAP_CONSTMSK_P_ = 0; generate if (AB_WIDTH == 0) begin + (* force_downto *) wire [LCU_WIDTH-1:0] CO; $lcu #(.WIDTH(LCU_WIDTH)) _TECHMAP_REPLACE_ (.P(P), .G(G), .CI(CI), .CO(CO)); assign Y = CO[LCU_WIDTH-1]; @@ -104,8 +114,10 @@ generate else begin // Propagate only if all pairs are equal // (inconclusive evidence to say A >= B) + (* force_downto *) wire [LCU_WIDTH-1:0] P_ = {P[LCU_WIDTH-1:1], P[0] & PP}; // Generate if any comparisons call for it + (* force_downto *) wire [LCU_WIDTH-1:0] G_ = {G[LCU_WIDTH-1:1], G[0] | GG}; end if (AB_WIDTH == 1) |