* 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.

From-SVN: r14768

1 files changed, 20 insertions, 1 deletions

diff --git a/gcc/rtl.h b/gcc/rtl.h
index d27b4e5..de9386d 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -317,7 +317,7 @@ enum reg_note { REG_DEAD = 1, REG_INC = 2, REG_EQUIV = 3, REG_WAS_0 = 4,
 		REG_NONNEG = 8, REG_NO_CONFLICT = 9, REG_UNUSED = 10,
 		REG_CC_SETTER = 11, REG_CC_USER = 12, REG_LABEL = 13,
 		REG_DEP_ANTI = 14, REG_DEP_OUTPUT = 15, REG_BR_PROB = 16,
-		REG_EXEC_COUNT = 17 };
+		REG_EXEC_COUNT = 17, REG_NOALIAS = 18 };
 /* The base value for branch probability notes.  */
 #define REG_BR_PROB_BASE  10000
 
@@ -803,6 +803,16 @@ extern rtx gen_ble			PROTO((rtx));
 extern rtx eliminate_constant_term	PROTO((rtx, rtx *));
 extern rtx expand_complex_abs		PROTO((enum machine_mode, rtx, rtx, int));
 extern enum machine_mode choose_hard_reg_mode PROTO((int, int));
+extern int rtx_varies_p		PROTO((rtx));
+extern int may_trap_p		PROTO((rtx));
+extern int side_effects_p	PROTO((rtx));
+extern int volatile_refs_p	PROTO((rtx));
+extern int volatile_insn_p	PROTO((rtx));
+extern void remove_note		PROTO((rtx, rtx));
+extern void note_stores		PROTO((rtx, void (*)()));
+extern int refers_to_regno_p	PROTO((int, int, rtx, rtx *));
+extern int reg_overlap_mentioned_p PROTO((rtx, rtx));
+
 
 /* Maximum number of parallel sets and clobbers in any insn in this fn.
    Always at least 3, since the combiner could put that many togetherm
@@ -959,3 +969,12 @@ extern char *regno_pointer_align;
    know what `enum tree_code' means.  */
 
 extern int rtx_to_tree_code	PROTO((enum rtx_code));
+
+extern int true_dependence	PROTO((rtx, enum machine_mode, rtx, int (*)()));
+extern int read_dependence	PROTO((rtx, rtx));
+extern int anti_dependence	PROTO((rtx, rtx));
+extern int output_dependence	PROTO((rtx, rtx));
+extern void init_alias_analysis	PROTO((void));
+extern void end_alias_analysis	PROTO((void));
+extern void mark_user_reg	PROTO((rtx));
+extern void mark_reg_pointer	PROTO((rtx, int));