https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116282
--- Comment #4 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:7aed8dedeb9613925930447bf2457c3fd9972d91 commit r15-2971-g7aed8dedeb9613925930447bf2457c3fd9972d91 Author: Jeff Law <j...@ventanamicro.com> Date: Sat Aug 17 09:52:55 2024 -0600 [RISC-V][PR target/116282] Stabilize pattern conditions So as expected the core problem with target/116282 is that the cost of certain constant synthesis cases varied depending on whether or not we're allowed to generate new pseudos or not. That in turn meant that in obscure cases an insn might change from recognizable to unrecognizable and triggers the observed failure. So we need to keep the cost stable, at least when called from a pattern's condition. So we pass another boolean down when necessary. I've tried to keep API fallout minimized. Built and tested on rv32 in my tester. Let's see what pre-commit testing has to say though ð Note this will also require a minor change to the in-flight constant synthesis work. PR target/116282 gcc/ * config/riscv/riscv-protos.h (riscv_const_insns): Add new argument. * config/riscv/riscv.cc (riscv_build_integer): Add new argument ALLOW_NEW_PSEUDOS. Pass it down to recursive calls and check it before using synthesis which allows new registers to be created. (riscv_split_integer_cost): Pass new argument to riscv_build_integer. (riscv_integer_cost): Add ALLOW_NEW_PSEUDOS argument, pass it down to riscv_build_integer. (riscv_legitimate_constant_p): Pass new argument to riscv_const_insns. (riscv_const_insns): New argment ALLOW_NEW_PSEUDOS. Pass it down to riscv_integer_cost and riscv_const_insns. (riscv_split_const_insns): Pass new argument to riscv_const_insns. (riscv_move_integer, riscv_rtx_costs): Similarly. * config/riscv/riscv.md (shadd with costly constant): Pass new argument to riscv_const_insns. * config/riscv/bitmanip.md (and with costly constant): Pass new argument to riscv_const_insns. gcc/testsuite/ * gcc.target/riscv/pr116282.c: New test.
