Masm for Rust's signed `overflowing_div` can produce wrong result

[mooori]

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Bug description

For example (-1i8).overflowing_div(-2i8):

Rust result: (0, false)
Rust result as bytes: [0, 0] // expected
Vm out bytes: [1, 0] // actual

Rust source

pub fn f(a: i8, b: i8) -> (i8, bool) {
    a.overflowing_div(b)
}

Potential explanation

Based on the generated test_overflowing_div_i8.hir:

• The generated hir entrypoint has i32 arguments for what are originally i8 operands
• Perhaps the operands have been zero-extended instead of sign-extended
  • -1i8 = 0xFF: zext yields 255i32, sext yields -1i32
  • -2i8 = 0xFE: zext yields 254i32, sext yields -2i32
  • 255/254 = 1 instead of -1/-2 = 0

How can this be reproduced?

• Checkout test: add tests for overflowing arith #959
• Unignore test_overflowing_div_i8 in rust_masm_tests/instructions.rs
• Execute it with:

UPDATE_EXPECT=1 cargo nextest run -p miden-integration-tests -- rust_masm_tests::instructions::test_overflowing_div_i8