py/emitnative: Fix case of clobbered REG_TEMP0 when loading const obj.

The `emit_load_reg_with_object()` helper function will clobber `REG_TEMP0`.
This is currently OK on architectures where `REG_RET` and `REG_TEMP0` are
the same (all architectures except RV32), because all callers of
`emit_load_reg_with_object()` use either `REG_RET` or `REG_TEMP0` as the
destination register.  But on RV32 these registers are different and so
when `REG_RET` is the destination, `REG_TEMP0` is clobbered, leading to
incorrectly generated machine code.

This commit fixes the issue simply by using `REG_TEMP0` as the destination
register for all uses of `emit_load_reg_with_object()`, and adds a comment
to make sure the caller of this function is careful.

Signed-off-by: Damien George <damien@micropython.org>

0 files changed, 0 insertions, 0 deletions