DFHDL #449 minimized - 2 designs, 31 lines

cell_histogram.scala

import dfhdl.*
class cell_histogram(
    val IMAGE_WIDTH: Int <> CONST = 640,
    val INPUT_BIN_WIDTH: Int <> CONST = 11,
    val OUTPUT_BIN_WIDTH: Int <> CONST = 14
) extends EDDesign:
  val BINS:                    Int <> CONST = 9 + 1
  val PARTIAL_HISTOGRAM_WIDTH: Int <> CONST = INPUT_BIN_WIDTH * BINS
  val CELLS_PER_ROW:           Int <> CONST = IMAGE_WIDTH / 8
  val histogram_adder = new partial_histogram_add(
    INPUT_BIN_WIDTH = INPUT_BIN_WIDTH, OUTPUT_BIN_WIDTH = OUTPUT_BIN_WIDTH, BINS = BINS)

others.scala

import dfhdl.*

class partial_histogram_add(
    val INPUT_BIN_WIDTH: Int <> CONST = 11,
    val OUTPUT_BIN_WIDTH: Int <> CONST = 14,
    val BINS: Int <> CONST = 9,
    val CELL_ROWS: Int <> CONST = 8
) extends EDDesign:
  val INPUT_WIDTH  = INPUT_BIN_WIDTH * BINS * CELL_ROWS
  val OUTPUT_WIDTH = OUTPUT_BIN_WIDTH * BINS
  val partial_histogram = Bits(INPUT_WIDTH)  <> VAR
  val full_histogram    = Bits(OUTPUT_WIDTH) <> VAR
  partial_histogram <> all(0)
  val ROW_OFFSETS = List(0, 99)
  process(all):
    for (i <- 0 until BINS)
      full_histogram.lsbitsAt(i * OUTPUT_BIN_WIDTH, OUTPUT_BIN_WIDTH) :=
        ROW_OFFSETS.map(off =>
          partial_histogram.lsbitsAt(i * INPUT_BIN_WIDTH + off, INPUT_BIN_WIDTH)
            .resize(OUTPUT_BIN_WIDTH)).reduce(_ + _)

reproduce.sh

#!/bin/bash
# DFHDL #449 minimized: 2 designs, 2 files, 31 lines.
#
# MUST run in a directory that has never been compiled before -- copy this tree
# to a NEW path per attempt (bloop keys incremental state by project path, so
# deleting src/.scala-build is NOT sufficient).
set -u
V=$(cat ~/.dfhdl_version)
b(){ scala run src/ --scala 3.8.4 --dep "io.github.dfianthdl::dfhdl::$V" \
     --compiler-plugin "io.github.dfianthdl:::dfhdl-plugin::$V" -O -deprecation \
     -M cell_histogram -- commit 2>&1; }
echo "1. build";  b >/tmp/1.log 2>&1 && echo "   ok" || { tail -3 /tmp/1.log; exit 1; }
echo "2. build again (populates the elaboration cache)"
                  b >/tmp/2.log 2>&1 && echo "   ok" || { tail -3 /tmp/2.log; exit 1; }
echo "3. change one parameter default"
sed -i 's/IMAGE_WIDTH: Int <> CONST = 640/IMAGE_WIDTH: Int <> CONST = 64/' src/cell_histogram.scala
echo "4. rebuild"
if b >/tmp/3.log 2>&1; then echo "   ok (did NOT reproduce - was this path used before?)"
else grep -m1 'NoSuchElementException: key not found: "TW_' /tmp/3.log && echo "   REPRODUCED"; fi
echo "5. clear dfhdl-cache, rebuild identical source"
find src/.scala-build -name dfhdl-cache -type d -exec rm -rf {} + 2>/dev/null
b >/tmp/4.log 2>&1 && echo "   ok - same source is fine once the cache is gone"