AUTO_MEMORIES detection cannot run as shipped

[oharboe]

AUTO_MEMORIES detection cannot run as shipped. Two bugs in
extract_memories.tcl, one commit each, in the order the flow hits them.

flow/Makefile orders the two steps correctly. Detection runs first and
produces the inventory, and gen_memories.py turns that into
results/memories/, which includes blackboxes.txt, the list of modules
synthesis is to blackbox:

$(RESULTS_DIR)/memories_inferred.json: $(VERILOG_FILES) $(SCRIPTS_DIR)/memories/extract_memories.tcl

do-auto-memories: $(RESULTS_DIR)/memories_inferred.json
	... --yosys-json $(RESULTS_DIR)/memories_inferred.json ...

1. The blackbox guard fires on the step that produces the blackbox
list. extract_memories.tcl reads its sources through
synth_preamble.tcl's read_design_sources, and every frontend branch
of that proc calls auto_memories_blackboxes, which errors when
results/memories/blackboxes.txt is absent. So the pass whose output
that list is derived from fails because the list does not exist yet.
The first commit clears AUTO_MEMORIES for the extraction process only.

2. proc reaches Tcl, not yosys. yosys -import cannot shadow a Tcl
built-in, and proc is the one that defines a procedure, so the bare
word defines a procedure instead of running the pass:

ERROR: TCL interpreter returned an error:
wrong # args: should be "proc name args body"

memory -nomap on the next line is unaffected, because memory is not
a Tcl built-in. The second commit qualifies the call as yosys proc,
which is how the flow already disambiguates elsewhere
(yosys read_slang in synth_preamble.tcl).

Either bug stops the pass on its own, and the second is reached on every
run, so the detection pass cannot have completed as shipped.

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request updates the extract_memories.tcl script to temporarily disable AUTO_MEMORIES by setting set ::env(AUTO_MEMORIES) 0 before reading design sources, preventing errors when the blackboxes file does not yet exist. Additionally, it replaces the bare proc command with yosys proc to ensure the Yosys command is executed rather than defining a Tcl procedure. There are no review comments, and I have no feedback to provide.

[openroad-ci]

🔍 QoR check

Metrics reflect the PR merge build — i.e. what will land on the target branch.

Commit 8f986f2 · Jenkins build #2 · Baseline: build · View build on dashboard

62 design(s) checked — 0 with regression(s), 1 without a comparable baseline.