Hi all,
Recently, I have been working on functional simulation and verification of
an extended complex instruction set for an AI chip based on the RISC-V
architecture using QEMU.
Given the complexity of some instructions, I attempted to introduce a set of
helper functions that can print certain intermediate results of IR
corresponding to a single instruction, such as those from sparse matrix
operations.
My implementation approach is as follows:
1. Encapsulate printf within helper functions (to avoid issues where the
printf
address might exceed the ±2GB address space when called directly). Since
helpers
do not support variadic arguments, I defined multiple helper_print
functions with
a maximum of 7 parameters.
2. Designed a syntactic sugar using C macros and the concatenation operator
##
to encapsulate the aforementioned helper_print functions, which can support
up
to 7 parameters.
However, I encountered some issues, such as having to set < #pragma GCC
diagnostic
ignored "-Wformat-security"> for this piece of code, but I think there might be
some security risks involved.
Currently, these macros are temporarily added under target/risc-v, but I believe
they could be designed more generally to support more architectures.
During testing, I found that these interfaces work particularly well for
debugging
simulations of complex instructions.
Therefore, I am sharing this patch with the mailing list in hopes that we can
discuss
and come up with a friendlier and more universal solution. :)
Regards,
Chao
Chao Liu (1):
riscv: Add gen_helper_print() to debug IR
target/riscv/helper.h | 13 ++++++++++++
target/riscv/op_helper.c | 46 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 59 insertions(+)
--
2.40.1
