Added self-documenting Makefile

Makefile

@@ -1,11 +1,49 @@
-MODE = machine
-VLEN = 256
-XLEN = 64
-SPLIT = 10000
-INTEGER = 0
-PATTERN = '.*'
-TESTFLOAT3LEVEL = 2
-REPEAT = 1
+##-----------------------------
+##RISC-V Vector Tests Generator
+##-----------------------------
+##
+##Usage: make all -j$(nproc) --environment-overrides [OPTIONS]
+##
+##Example: to generate isa=rv32gcv varch=vlen:128,elen:32 mode=machine tests, use:
+## make all --environment-overrides VLEN=128 XLEN=32 MODE=machine -j$(nproc)
+##
+##Subcommands:
+  help: ## Show this help message.
+	@fgrep -h "##" $(MAKEFILE_LIST) | fgrep -v fgrep | sed -e 's/\\$$//' | sed -e 's/##//'
+
+  all:  ## Generate tests.
+  all: compile-stage2
+
+##
+##Options:
+
+  MODE = machine##
+        ##Can be [machine], [virtual] or [user]; for more info, see https://github.com/riscv/riscv-test-env
+        ##
+  VLEN = 256##
+        ##Can vary from [64] to [4096] (upper boundary is limited by Spike)
+        ##
+  XLEN = 64##
+        ##Can be [32] or [64]; note that we do not support specifying ELEN yet, ELEN is always consistent with XLEN
+        ##
+  SPLIT = 10000##
+        ##Split on assembly file lines (excluding test data)
+        ##
+  INTEGER = 0##
+        ##Set to [1] if you don't want float tests (i.e. for Zve32x or Zve64x)
+        ##
+  PATTERN = '.*'##
+        ##Set to a valid regex to generate the tests of your interests (e.g. PATTERN='^v[ls].+\.v$' to generate only load/store tests)
+        ##
+  TESTFLOAT3LEVEL = 2##
+        ##Testing level for testfloat3 generated cases, can be one of [1] or [2].
+        ##
+  REPEAT = 1##
+        ##Set to greater value to repeat the same V instruction n times for a better coverage (only valid for float instructions).
+        ##
+  TEST_MODE = self##
+        ##Change to [cosim] if you want to generate faster tests without self-verification (to be used with co-simulators).
+        ##
 SPIKE_INSTALL = $(RISCV)
 OUTPUT = out/v$(VLEN)x$(XLEN)$(MODE)
 OUTPUT_STAGE1 = $(OUTPUT)/tests/stage1/
@@ -14,7 +52,6 @@ OUTPUT_STAGE2_PATCH = $(OUTPUT)/patches/stage2/
 OUTPUT_STAGE1_BIN = $(OUTPUT)/bin/stage1/
 OUTPUT_STAGE2_BIN = $(OUTPUT)/bin/stage2/
 CONFIGS = configs/
-TEST_MODE = self
 
 SPIKE = spike
 PATCHER_SPIKE = build/pspike
@@ -54,8 +91,6 @@ ENV = env/riscv-test-env/v
 ENV_CSRCS = env/riscv-test-env/v/vm.c env/riscv-test-env/v/string.c env/riscv-test-env/v/entry.S
 endif
 
-all: compile-stage2
-
 build: build-generator build-merger
 
 build-generator:

README.md

@@ -27,18 +27,7 @@ make -j$(nproc)
 
 After `make`, you will find all the generated tests in `out/v[vlen]x[xlen][mode]/bin/stage2/`.
 
-Options:
-
-- `VLEN`, default is 256
-- `XLEN`, default is 64, we do not support specifying ELEN yet, ELEN is consistent with XLEN
-- `MODE`, default is `machine`, can be `machine`, `virtual` or `user`
-- `INTEGER`, default is 0, set to 1 if you don't want float tests (i.e. for Zve32x or Zve64x)
-- `PATTERN`, default is `.*`, set to a valid regex to generate the tests of your interests (e.g. `PATTERN='^v[ls].+\.v$'` to generate load/store tests)
-- `TESTFLOAT3LEVEL`, default is 2, must be one of 1 or 2, testing level for testfloat3 generated cases.
-- `TEST_MODE`, default is `self`, set to `cosim` if you want to generate faster tests without self-verification (to be used with co-simulators).
-- `REPEAT`, default is `1`, set to greater value to repeat the same V instruction n times for a better coverage (only valid for float instructions).
-
-For example, to generate `isa=rv32gcv varch=vlen:128,elen:32 mode=machine` tests, use `make -e VLEN=128 XLEN=32 MODE=machine -j$(nproc)`.
+For more advanced options, run `make help`.
 
 > Note: [single/single.go](single/single.go) generates tests directly from stage 1, suitable for targets with co-simulators (or simply use `TEST_MODE=cosim` if you're lazy).