https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114639
--- Comment #14 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Pan Li <pa...@gcc.gnu.org>: https://gcc.gnu.org/g:e40a3d86511efcea71e9eadde8fb9f96be52f790 commit r14-9908-ge40a3d86511efcea71e9eadde8fb9f96be52f790 Author: Pan Li <pan2...@intel.com> Date: Thu Apr 11 09:39:44 2024 +0800 RISC-V: Bugfix ICE for the vector return arg in mode switch This patch would like to fix a ICE in mode sw for below example code. during RTL pass: mode_sw test.c: In function âvbool16_t j(vuint64m4_t)â: test.c:15:1: internal compiler error: in create_pre_exit, at mode-switching.cc:451 15 | } | ^ 0x3978f12 create_pre_exit __RISCV_BUILD__/../gcc/mode-switching.cc:451 0x3979e9e optimize_mode_switching __RISCV_BUILD__/../gcc/mode-switching.cc:849 0x397b9bc execute __RISCV_BUILD__/../gcc/mode-switching.cc:1324 extern size_t get_vl (); vbool16_t test (vuint64m4_t a) { unsigned long b; return __riscv_vmsne_vx_u64m4_b16 (a, b, get_vl ()); } The create_pre_exit would like to find a return value copy. If not, there will be a reason in assert but not available for above sample code when vector calling convension is enabled by default. This patch would like to override the TARGET_FUNCTION_VALUE_REGNO_P for vector register and then we will have hard_regno_nregs for copy_num, aka there is a return value copy. As a side-effect of allow vector in TARGET_FUNCTION_VALUE_REGNO_P, the TARGET_GET_RAW_RESULT_MODE will have vector mode and which is sizeless cannot be converted to fixed_size_mode. Thus override the hook TARGET_GET_RAW_RESULT_MODE and return VOIDmode when the regno is-not-a fixed_size_mode. The below tests are passed for this patch. * The fully riscv regression tests. * The reproducing test in bugzilla PR114639. PR target/114639 gcc/ChangeLog: * config/riscv/riscv.cc (riscv_function_value_regno_p): New func impl for hook TARGET_FUNCTION_VALUE_REGNO_P. (riscv_get_raw_result_mode): New func imple for hook TARGET_GET_RAW_RESULT_MODE. (TARGET_FUNCTION_VALUE_REGNO_P): Impl the hook. (TARGET_GET_RAW_RESULT_MODE): Ditto. * config/riscv/riscv.h (V_RETURN): New macro for vector return. (GP_RETURN_FIRST): New macro for the first GPR in return. (GP_RETURN_LAST): New macro for the last GPR in return. (FP_RETURN_FIRST): Diito but for FPR. (FP_RETURN_LAST): Ditto. (FUNCTION_VALUE_REGNO_P): Remove as deprecated and replace by TARGET_FUNCTION_VALUE_REGNO_P. gcc/testsuite/ChangeLog: * g++.target/riscv/rvv/base/pr114639-1.C: New test. * gcc.target/riscv/rvv/base/pr114639-1.c: New test. Signed-off-by: Pan Li <pan2...@intel.com>
