On 04/02/14 12:27, Richard Sandiford wrote: > This patch adds return and simple_return patterns to the s390 backend, > which eanbles shrink-wrapping and conditional returns to be used. > > Perhaps the only subtle thing is the handling of call-clobbered base > registers. The idea is to emit the initialising main_pool pattern in > both early_mach -- at the very beginning of the function -- and in the > prologue. Then, if shrink-wrapping is used, the one added by early_mach > will still be the first in the function. If shrink-wrapping isn't used > then the one added by the prologue will be the first in the function. > s390_mainpool_start then deletes whichever isn't needed. > > Tested in the same way as the previous patches. OK to install? > > Thanks, > Richard > > > gcc/ > * config/s390/s390-protos.h (s390_can_use_simple_return_insn) > (s390_can_use_return_insn): Declare. > * config/s390/s390.h (EPILOGUE_USES): Define. > * config/s390/s390.c (s390_mainpool_start): Allow two main_pool > instructions. > (s390_chunkify_start): Handle return JUMP_LABELs. > (s390_early_mach): Emit a main_pool instruction on the entry edge. > (s300_set_up_by_prologue, s390_can_use_simple_return_insn) > (s390_can_use_return_insn): New functions. > (s390_fix_long_loop_prediction): Handle conditional returns. > (TARGET_SET_UP_BY_PROLOGUE): Define. > * config/s390/s390.md (ANY_RETURN): New code iterator. > (*creturn, *csimple_return, return, simple_return): New patterns.
Ok to apply. Thanks! -Andreas-
