spike --isa=rv32im tries to use the 64bit version of `pk`. No termination of 32 bit programs

[ghost]

hello,

I have a gcc toolchain built for RV32IM. I experienced the "no termination problem" (e.g. as reported here https://github.com/riscv/riscv-pk/issues/92) and investigated a bit.

A possible explanation for this issue is that Spike looks for the 64bit version of pk even though we run a 32-bit executable.

Spike is configured/built with --prefix=$RISCV --with-fesvr=$RISCV --with-isa=rv32im

The gcc toolchain is configured/built with --prefix=$RISCV --with-arch=rv32im --with-abi=ilp32 --disable-linux

PK is configured/built with --prefix=$RISCV --host=riscv32-unknown-elf --enable-32bit.

Here I suspect that Spike finds pk in the current directory, built for 32bit, and everything is fine:

$ cd $TOP/riscv-pk/build
$ echo -e '#include <stdio.h>\n int main(void) { printf("Hello world!\\n"); return 0; }' > hello.c && riscv32-unknown-elf-gcc -o hello hello.c && spike pk hello
Hello world!

If I run Spike from another directory, spike fallbacks to the 64bit version of pk:

damien@gre051335:~/projets/SERENE/src/polen-infra/riscv-tools(build-rv32im)          sam. mai 05 11:21:19
$ cd $TOP
$ find -name pk
./riscv-pk/pk
./riscv-pk/build/pk
./riscv/riscv64-unknown-elf/bin/pk
./riscv/riscv32-unknown-elf/bin/pk
$ echo -e '#include <stdio.h>\n int main(void) { printf("Hello world!\\n"); return 0; }' > hello.c && riscv32-unknown-elf-gcc -o hello hello.c && spike pk hello
    # here the program does not terminate. Halted with ctrl-C.
^C: 
core   0: 0x0000000080000004 (0x34011173) csrrw   sp, mscratch, sp
: 
core   0: 0xffffffff80000008 (0x1a010063) beqz    sp, pc + 416
: 
core   0: 0xffffffff8000000c (0x04a13823) sd      a0, 80(sp)
core   0: exception trap_illegal_instruction, epc 0xffffffff8000000c
core   0:           tval 0x0000000000000000
: 
core   0: 0x0000000080000004 (0x34011173) csrrw   sp, mscratch, sp

Renaming the 64bit version of pk makes Spike unhappy:

$ cd $TOP
$ find -name pk
./riscv-pk/pk
./riscv-pk/build/pk
./riscv/riscv64-unknown-elf/bin/pk
./riscv/riscv32-unknown-elf/bin/pk
$ mv ./riscv/riscv64-unknown-elf/bin/pk ./riscv/riscv64-unknown-elf/bin/pk64 
$ echo -e '#include <stdio.h>\n int main(void) { printf("Hello world!\\n"); return 0; }' > hello.c && riscv32-unknown-elf-gcc -o hello hello.c && spike pk hello
terminate called after throwing an instance of 'std::runtime_error'
  what():  could not open pk (did you misspell it? If VCS, did you forget +permissive/+permissive-off?)

Last, copying the 32-bit version of pk in the current directory makes Spike happy again:

$ cd $TOP
$ mv ./riscv/riscv64-unknown-elf/bin/pk64 ./riscv/riscv64-unknown-elf/bin/pk
$ find -name pk
./riscv-pk/pk
./riscv-pk/build/pk
./riscv/riscv64-unknown-elf/bin/pk
./riscv/riscv32-unknown-elf/bin/pk
$ cp ./riscv/riscv32-unknown-elf/bin/pk .
$ echo -e '#include <stdio.h>\n int main(void) { printf("Hello world!\\n"); return 0; }' > hello.c && riscv32-unknown-elf-gcc -o hello hello.c && spike pk hello
Hello world!

[emelcher]

This issue is related.

[ghost]

https://github.com/riscv/riscv-pk/issues/39

It looks like spike does not find pk at its expected location. So I assume the problem is more on spike's side.

Any hints?

[nmeum]

I think I had the same issue you described, the thing is that spike uses the RV64IMAFDC ISA by default. If I attempt to invoke a hello word program cross compiled with riscv32-unknown-elf-gcc with this ISA spike doesn't terminate on my system either.

I managed to fix this by invoking spike as spike --isa=RV32IMAFDC pk test where test is a hello world program cross compiled with riscv32-unknown-elf-gcc.

[ibndias]

spike --isa=RV32IMAFDC pk test works, but the --isa=RV32IMAFD doesn't!

I recheck my riscv-gnu-toolchain, it was compiled with --with-arch=rv32gc as mentioned by the readme.md while my spike was compiled with --with-isa=rv32ima because i was using riscv-tools's build-rv32ima.sh

So the exception trap_illegal_instruction was because the program has compressed instruction that's not supported by the spike