https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116256
--- Comment #9 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jeff Law <l...@gcc.gnu.org>: https://gcc.gnu.org/g:9d68a2a67351fc5b56262c0028ef8fd1d1466627 commit r15-8080-g9d68a2a67351fc5b56262c0028ef8fd1d1466627 Author: Jeff Law <j...@ventanamicro.com> Date: Sun Mar 16 17:43:48 2025 -0600 [RISC-V][PR target/116256][V4] Fix minor code quality regression in reassociated arithmetic Arggh. This time add arguments for rv32. Hand edited the testcase part of the patch, but I think I got it right. One. More. Time. -pedantic-errors this time ;( Adding an explicit -std=gnu23 to shut that up. Part of me wants to know why that's getting added by the pre-commit, but not enough to chase it down. -- This failed pre-commit CI the first time through. The only change is in the return type in the test bool -> _Bool. The patch for target/116256 significantly simplified the condition and, I guess not too surprisingly, exposed a minor code quality regression. Specifically the split part of the define_insn_and_split only splits after reload (because we use a match_scratch). So there's nothing to combine the load-immediate with the subsequent add into an addi when the immediate fits into a simm12 field. This patch adjusts the split code to handle that scenario directly and generate the more efficient code. We can squeeze out the slli in this test with a bit more work, but that's out of scope right now since that isn't a regression. Tested in my tester. Waiting on pre-commit testing to render a verdict. PR target/116256 gcc * config/riscv/riscv.md (reassociation splitters): Do not load the adjusted addend into a register if it fits in a simm12. gcc/testsuite * gcc.target/riscv/pr116256-1.c: New test.
