From 166a175983edeacb9494e084ef84f6f7fdec1d91 Mon Sep 17 00:00:00 2001
From: gatecat <gatecat@ds0.me>
Date: Sun, 1 May 2022 09:24:17 +0100
Subject: [PATCH] abc9_ops: Don't leave unused derived modules lying around
These later become accidentally used for techmap replacements for
blackboxes that we don't actually want.
Signed-off-by: gatecat <gatecat@ds0.me>
---
passes/techmap/abc9_ops.cc | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/passes/techmap/abc9_ops.cc b/passes/techmap/abc9_ops.cc
index b8975f178..acafb0b65 100644
--- a/passes/techmap/abc9_ops.cc
+++ b/passes/techmap/abc9_ops.cc
@@ -155,6 +155,9 @@ void prep_hier(RTLIL::Design *design, bool dff_mode)
r.first->second = new Design;
Design *unmap_design = r.first->second;
+ // Keep track of derived versions of modules that we haven't used, to prevent these being used for unwanted techmaps later on.
+ pool<IdString> unused_derived;
+
for (auto module : design->selected_modules())
for (auto cell : module->cells()) {
auto inst_module = design->module(cell->type);
@@ -169,6 +172,7 @@ void prep_hier(RTLIL::Design *design, bool dff_mode)
else {
derived_type = inst_module->derive(design, cell->parameters);
derived_module = design->module(derived_type);
+ unused_derived.insert(derived_type);
}
if (derived_module->get_bool_attribute(ID::abc9_flop)) {
@@ -192,6 +196,7 @@ void prep_hier(RTLIL::Design *design, bool dff_mode)
// as a compatible type, yet will be safely unmapped later
cell->type = derived_type;
cell->parameters.clear();
+ unused_derived.erase(derived_type);
}
continue;
}
@@ -250,7 +255,11 @@ void prep_hier(RTLIL::Design *design, bool dff_mode)
cell->type = derived_type;
cell->parameters.clear();
+ unused_derived.erase(derived_type);
}
+ for (auto unused : unused_derived) {
+ design->remove(design->module(unused));
+ }
}
void prep_bypass(RTLIL::Design *design)