Added $lut support to blif backend (by user eddiehung from reddit)

diff --git a/backends/blif/blif.cc b/backends/blif/blif.cc
index 1c06fe519563144de69701be680516aa0cc7aa91..498f13511658c64d4379cf5e11fbe85423fcb2d5 100644 (file)
--- a/backends/blif/blif.cc
+++ b/backends/blif/blif.cc
@@ -190,6 +190,29 @@ struct BlifDumper
                                continue;
                        }
 
+                       if (!config->icells_mode && cell->type == "$lut") {
+                               fprintf(f, ".names");
+                               auto &inputs = cell->connections.at("\\I");
+                               auto width = cell->parameters.at("\\WIDTH").as_int();
+                               log_assert(inputs.width == width);
+                               for (int i = 0; i < inputs.width; i++) {
+                                       fprintf(f, " %s", cstr(inputs.extract(i, 1)));
+                               }
+                               auto &output = cell->connections.at("\\O");
+                               log_assert(output.width == 1);
+                               fprintf(f, " %s", cstr(output));
+                               fprintf(f, "\n");
+                               auto mask = cell->parameters.at("\\LUT").as_string();
+                               for (int i = 0; i < (1 << width); i++) {
+                                       if (mask[i] == '0') continue;
+                                       for (int j = width-1; j >= 0; j--) {
+                                               fputc((i>>j)&1 ? '1' : '0', f);
+                                       }
+                                       fprintf(f, " %c\n", mask[i]);
+                               }
+                               continue;
+                       }
+
                        fprintf(f, ".%s %s", subckt_or_gate(cell->type), cstr(cell->type));
                        for (auto &conn : cell->connections)
                        for (int i = 0; i < conn.second.width; i++) {