On 8/30/26 8:26 PM, wangjue wrote:
From: juewang <[email protected]>
Handle conditional arithmetic wrapped in a sign or zero extension when
the unchanged value is known to have the same extension. Query the
promoted lowpart directly instead of searching for its definition.
gcc/ChangeLog:
* ifcvt.cc (noce_cond_arith_operation): New function.
(noce_operand_known_extended_p): New function.
(noce_try_cond_arith): Handle arithmetic operations wrapped in an
extension.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/pr122769.c: Add the branch cost and restrict the
test to compatible optimization options.
* gcc.target/riscv/zicond-conditional-add-extend.c: New test.
Thanks. Please make sure to note how you've tested patches. For a
patch to the generic part of the compiler the patch must be bootstrapped
and regression tested on a major target (x86_64 and aarch64 are the most
common).
I took care of throwing this into my tester overnight. While the
nightly runs aren't done, it did pass x86_64 and aarch64 with no
regressions.
However, it did flag a failure on riscv64-elf. In particular
gcc.target/riscv/pr123322.c fails. It's pretty obvious that the test in
question just needed to be updated for the improved code generation.
I've fixed that and pushed your patch to the trunk.
Thanks!
jeff
