aarch64_secondary_reload enforced a secondary reload via aarch64_sve_reload_be for memory and pseudo registers, but failed to do the same for subregs of pseudo registers. To avoid this and any similar problems, the patch instead tests for things that the move patterns handle directly; if the operand isn't one of those, we should use the reload pattern instead.
The patch fixes an ICE in sve/mask_struct_store_3.c for aarch64_be, where the bogus target description was (rightly) causing LRA to cycle. Tested on aarch64_be-elf and aarch64-linux-gnu. OK to install? Richard 2018-01-26 Richard Sandiford <richard.sandif...@linaro.org> gcc/ PR tearget/83845 * config/aarch64/aarch64.c (aarch64_secondary_reload): Tighten check for operands that need to go through aarch64_sve_reload_be. Index: gcc/config/aarch64/aarch64.c =================================================================== --- gcc/config/aarch64/aarch64.c 2018-01-19 11:57:11.141991997 +0000 +++ gcc/config/aarch64/aarch64.c 2018-01-26 13:32:54.240529011 +0000 @@ -7249,9 +7249,14 @@ aarch64_secondary_reload (bool in_p ATTR machine_mode mode, secondary_reload_info *sri) { + /* Use aarch64_sve_reload_be for SVE reloads that cannot be handled + directly by the *aarch64_sve_mov<mode>_be move pattern. See the + comment at the head of aarch64-sve.md for more details about the + big-endian handling. */ if (BYTES_BIG_ENDIAN && reg_class_subset_p (rclass, FP_REGS) - && (MEM_P (x) || (REG_P (x) && !HARD_REGISTER_P (x))) + && !((REG_P (x) && HARD_REGISTER_P (x)) + || aarch64_simd_valid_immediate (x, NULL)) && aarch64_sve_data_mode_p (mode)) { sri->icode = CODE_FOR_aarch64_sve_reload_be;