* Integrate alias analysis changes from jfc@mit.edu

        * Makefile.in (OBJS): Add alias.o
        (alias.o): Add dependencies.
        * alias.c: New file.
        * sched.c: Remove alias analysis code.  It lives in alias.c now.
        (reg_last_uses_size): Declare.
        (sched_analyze_2): Add new arguments to true_dependence.
        (sched_analyze_insn): Use reg_last_uses_size instead of max_reg.
        (schedule_block): Initialize reg_last_uses_size.
        (schedule_insns): Always call init_alias_analysis.
        * calls.c (expand_call): Note calls to malloc, calloc, and realloc;
        mark return value from such functions as a pointer and keep track of
        them for alias analysis.  If a return value from a function is a
        pointer, mark it as such.
        * combine.c (distribute_notes): Handle REG_NOALIAS.
        * cse.c (struct write_data): Delete.  No longer needed.
        (invalidate): Don't call set_nonvarying_address_components anymore.
        Use true_dependence to decide if an entry should be removed from
        the hash table.
        (invalidate_memory): Remove WRITES argument, simplify appropriately.
        Fix all callers.
        (note_mem_written): Similarly for WRITE_PTR argument.
        (invalidate_from_clobbers): Similarly for W argument.
        (invalidate_for_call): Remove memory elements from the hash table.
        (refers_to_mem_p, cse_rtx_addr_varies_p): Deleted.
        (cse_rtx_varies_p): New function.  Derived from old
        cse_rtx_addr_varies_p.
        (cse_insn): Remove WRITES_MEMORY and INIT variables and all references.
        Don't call note_mem_written anymore.  Stack pushes invalidate the stack
        pointer if PUSH_ROUNDING is defined.  No longer need to call
        cse_rtx_addr_varies_p to decide if a MEM should be invalidated.
        (skipped_writes_memory): Remove variable.
        (invalidate_skipped_set): Simplify and wewrite to use invalidate_memory.
        (invalidate_skipped_block): Simplify for new alias analysis code.
        (cse_set_around_loop): Likewise.
        (cse_main): Call init_alias_analysis.
        * flags.h (flag_alias_check, flag_argument_noalias): Declare.
        * toplev.c (flag_alias_check, flag_argument_noalias): Define.
        (f_options): Add new alias checking arguments.
        (main): Set flag_alias_check when optimizing.
        * local_alloc (validate_equiv_mem_from_store): Add new arguments
        to true_dependence.
        (memref_referenced_p): Likewise.
        * loop.c (NUM_STORES): Increase to 30.
        (prescan_loop): Only non-constant calls set unknown_address_altered.
        (invariant_p): Add new arguments to true_dependence.
        (record_giv): Initialize unrolled and shared fields.
        (emit_iv_add_mult): Call record_base_value as needed.
        * loop.h (struct induction): Add unrolled and shared fields.
        * unroll.c  (unroll_loop): Call record_base_value as needed.
        (copy_loop_body): Likewise.
        (final_biv_value): Likewise.
        (final_giv_value): Likewise.
        (find_splittable_regs): Likewise.  Only create one new pseudo
        if we have multiple address GIVs that were combined with the same
        dst_reg GIV.  Note when a new register is created due to unrolling.
        * rtl.c (reg_note_name): Add REG_NOALIAS.
        * rtl.h (enum reg_note): Similarly.
        (rtx_varies_p, may_trap_p, side_effects_p): Declare.
        (volatile_refs_p, volatile_insn_p, remove_note): Likewise.
        (note_stores, refers_to_regno_p, reg_overlap_mentioned_p): Likewise.
        (true_dependence, read_dependence, anti_dependence): Likewise.
        (output_dependence, init_alias_analysis, end_alias_analysis): Likewise.
        (mark_user_reg, mark_reg_pointer): Likewise.
jfc's alias analysis code.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@14768 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 1 insertions, 0 deletions

diff --git a/gcc/combine.c b/gcc/combine.c
index 44cca31aec8..7ce64e45b71 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -11058,6 +11058,7 @@ distribute_notes (notes, from_insn, i3, i2, elim_i2, elim_i1)
 	case REG_EQUAL:
 	case REG_EQUIV:
 	case REG_NONNEG:
+	case REG_NOALIAS:
 	  /* These notes say something about results of an insn.  We can
 	     only support them if they used to be on I3 in which case they
 	     remain on I3.  Otherwise they are ignored.