Makefile

TARGET   := game
BUILD    := build
SOURCES  := source
INCLUDE  := include

CC       := arm-none-eabi-gcc
AS       := arm-none-eabi-gcc
OBJCOPY  := arm-none-eabi-objcopy

ARCH     := -mcpu=arm7tdmi -mtune=arm7tdmi
CFLAGS   := $(ARCH) -mthumb -mthumb-interwork -O2 -Wall -Wextra \
            -ffreestanding -fno-builtin -DGBA_BUILD -I$(INCLUDE)
ASFLAGS  := $(ARCH) -mthumb-interwork -x assembler-with-cpp
# -lgcc: software integer division/64-bit helpers (ARM7TDMI has no divider)
LDFLAGS  := $(ARCH) -mthumb -mthumb-interwork -T gba.ld -nostartfiles -nostdlib -Wl,-Map,$(BUILD)/$(TARGET).map
LDLIBS   := -lgcc

C_FILES  := $(wildcard $(SOURCES)/*.c)
S_FILES  := $(SOURCES)/crt0.s $(filter-out $(SOURCES)/crt0.s,$(wildcard $(SOURCES)/*.s))
OBJS     := $(patsubst $(SOURCES)/%.c,$(BUILD)/%.o,$(C_FILES)) \
            $(patsubst $(SOURCES)/%.s,$(BUILD)/%.o,$(S_FILES))

.PHONY: all clean run host model

all: $(BUILD)/$(TARGET).gba

# regenerate source/model_data.c + include/model_data.h from the weights
model:
	python3 tools/export_model.py model/stories260K.bin model/tok512.bin .

# native build of the same engine, for fast testing (host/test_llm.c)
host: | $(BUILD)
	gcc -O2 -Wall -I$(INCLUDE) host/test_llm.c $(SOURCES)/llm.c $(SOURCES)/model_data.c -o $(BUILD)/host_llm

$(BUILD)/%.o: $(SOURCES)/%.c | $(BUILD)
	$(CC) $(CFLAGS) -c $< -o $@

$(BUILD)/%.o: $(SOURCES)/%.s | $(BUILD)
	$(AS) $(ASFLAGS) -c $< -o $@

$(BUILD)/$(TARGET).elf: $(OBJS) gba.ld
	$(CC) $(LDFLAGS) $(OBJS) $(LDLIBS) -o $@

# gbafix (vendored from devkitPro gba-tools) embeds the Nintendo logo and
# fixes the header checksums -- required for the ROM to boot on real hardware.
$(BUILD)/gbafix: tools/gbafix.c | $(BUILD)
	cc -O2 -o $@ $<

$(BUILD)/$(TARGET).gba: $(BUILD)/$(TARGET).elf $(BUILD)/gbafix
	$(OBJCOPY) -O binary $< $@
	$(BUILD)/gbafix $@
	@echo "Built $@ (real-hardware ready)"

$(BUILD):
	mkdir -p $(BUILD)

run: $(BUILD)/$(TARGET).gba
	mgba $(BUILD)/$(TARGET).gba

clean:
	rm -rf $(BUILD)