r265490 allowed the compiler to choose in a more flexible way whether to
use load or load-address-relative-long (LARL) instruction. When it
chose LARL for literal pool references, the latter ones were rewritten
by pass_s390_early_mach to use UNSPEC_LTREF, which assumes base register
usage, which in turn is not compatible with LARL. The end result was an
ICE because of unrecognizable insn.
UNSPEC_LTREF and friends are necessary in order to communicate the
dependency on the base register to pass_sched2. When relative
addressing is used, no base register is necessary, so in such cases the
rewrite must be avoided.
gcc/ChangeLog:
2018-11-09 Ilya Leoshkevich <iii@linux.ibm.com>
PR target/87762
* config/s390/s390.c (s390_safe_relative_long_p): New function.
(annotate_constant_pool_refs): Skip insns which support
relative addressing.
(annotate_constant_pool_refs_1): New helper function.
(find_constant_pool_ref): Skip insns which support relative
addression.
(find_constant_pool_ref_1): New helper function.
(replace_constant_pool_ref): Skip insns which support
relative addressing.
(replace_constant_pool_ref_1): New helper function.
(s390_mainpool_start): Adapt to the new signature.
(s390_mainpool_finish): Likewise.
(s390_chunkify_start): Likewise.
(s390_chunkify_finish): Likewise.
(pass_s390_early_mach::execute): Likewise.
(s390_prologue_plus_offset): Likewise.
(s390_emit_prologue): Likewise.
(s390_emit_epilogue): Likewise.
From-SVN: r265991
