riscv-tests

riscv-tests

This is a subset of test outputs generated by https://github.com/riscv-software-src/riscv-tests The generated test vectors are checked into version control to make the testing more portable.

The test-vectors are licensed by the test generation license, also available here LICENSE

Building unit tests (requires riscv64-unknown-elf toolchain):

git clone [email protected]:riscv-software-src/riscv-tests.git
cd riscv-tests

export RISCV=/opt/riscv
git submodule update --init --recursive
autoconf
./configure --prefix=$RISCV/target
RISCV_PREFIX="/opt/riscv/bin/riscv64-unknown-elf-" make

# files are output to the isa/ directory, e.g.
ls isa/rv64ui-p-*

# Selecting the test-vectors for Asterisc:
mkdir riscv-tests/rv64ua-p
mkdir riscv-tests/rv64ui-p
mkdir riscv-tests/rv64um-p
mkdir riscv-tests/benchmarks

cp isa/rv64ua-p-* riscv-tests/rv64ua-p/
cp isa/rv64ui-p-* riscv-tests/rv64ui-p/
cp isa/rv64um-p-* riscv-tests/rv64um-p/
cp benchmarks/*.riscv riscv-tests/benchmarks
cp benchmarks/*.riscv.dump riscv-tests/benchmarks

• riscv_test.h defines test environment things
• The "TVM" (test virtual machine) is the feature set required by a test
• We're only interested in rv64u*: 64 bit user-level integer-only instructions.
  • We only care about i (base integer set), and a (atomics), m (multiplication) extensions
  • We don't need the floating point, 32 bit, supervisor variants.
• And there are different target environments too. But we only care about single-core.
  • p = single core, physical memory
  • v = virtual memory enabled, may be interesting (TODO)
  • ignore multi-core tests

Test structure is documented here: https://riscv.org/wp-content/uploads/2015/01/riscv-testing-frameworks-bootcamp-jan2015.pdf But lacks test format definition.

Test format (reverse engineered, cannot find docs):

• ELF file for each test suite to execute
• a .dump file with the matching assembly to understand the test
• entry-point seems to always be 0x80_00_00_00
• test case is small part of it, and test number is contained in register gp during test
  • 1137 is used to indicate exceptions
• cases jump to fail if bad, with single-argument syscall calling convention to signal result:
  • a0 is set to (test_case_num << 1) | 1
  • a7 is set to the function ID, 93 (exit)
  • ecall, indicating test num and fail status
• if not to fail, we end at pass, again a syscall:
  • a0 is set to 0
  • a7 is set to the function ID, 93 (exit)
  • ecall

The .dump files are the disassembled versions of the respective binary files; useful data during test debugging.