Here's the command I use to test:
LD_LIBRARY_PATH=~/nacl/v8/out/native/lib.target make -j48 \
-f Makefile.standalone WASM=1 && \
LD_LIBRARY_PATH=~/nacl/v8/out/native/lib.target ./pnacl-sz -O2 -filetype=asm \
-target=arm32 ./torture-s2wasm-sexpr-wasm/20000112-1.c.s.wast.wasm
You'll probably need to adjust your LD_LIBRARY_PATH to point to where your v8 libraries are.
You'll need to build v8 as a shared library. Build it like this:
make -j48 native component=shared_library
wasm-run-torture-tests.py can be used to run all the tests, or some subset. Running a subset will enable verbose output. You can download the torture tests from the WebAssembly waterfall.