The following removes safelen handling from LIM - it is not really
useful information to it and it was used to derive incorrect conclusions
about dependences.
Bootstrapped and tested on x86_64-unknown-linux-gnu.
I'll commit this on Monday to leave some time for comments (but many
are already in the PR).
Richard.
2017-12-15 Richard Biener <rguent...@suse.de>
PR tree-optimization/81877
* tree-ssa-loop-im.c (ref_indep_loop_p): Remove safelen parameters.
(outermost_indep_loop): Adjust.
(ref_indep_loop_p_1): Likewise. Remove safelen handling again.
(can_sm_ref_p): Adjust.
* g++.dg/torture/pr81877.C: New testcase.
* g++.dg/vect/pr70729.cc: XFAIL.
* g++.dg/vect/pr70729-nest.cc: XFAIL.
Index: gcc/tree-ssa-loop-im.c
===================================================================
--- gcc/tree-ssa-loop-im.c (revision 255678)
+++ gcc/tree-ssa-loop-im.c (working copy)
@@ -199,7 +199,7 @@ static struct
static bitmap_obstack lim_bitmap_obstack;
static obstack mem_ref_obstack;
-static bool ref_indep_loop_p (struct loop *, im_mem_ref *, struct loop *);
+static bool ref_indep_loop_p (struct loop *, im_mem_ref *);
static bool ref_always_accessed_p (struct loop *, im_mem_ref *, bool);
/* Minimum cost of an expensive expression. */
@@ -548,10 +548,10 @@ outermost_indep_loop (struct loop *outer
aloop != loop;
aloop = superloop_at_depth (loop, loop_depth (aloop) + 1))
if ((!ref->stored || !bitmap_bit_p (ref->stored, aloop->num))
- && ref_indep_loop_p (aloop, ref, loop))
+ && ref_indep_loop_p (aloop, ref))
return aloop;
- if (ref_indep_loop_p (loop, ref, loop))
+ if (ref_indep_loop_p (loop, ref))
return loop;
else
return NULL;
@@ -2150,20 +2150,13 @@ record_dep_loop (struct loop *loop, im_m
}
/* Returns true if REF is independent on all other memory
- references in LOOP. REF_LOOP is where REF is accessed, SAFELEN is the
- safelen to apply. */
+ references in LOOP. */
static bool
-ref_indep_loop_p_1 (int safelen, struct loop *loop, im_mem_ref *ref,
- bool stored_p, struct loop *ref_loop)
+ref_indep_loop_p_1 (struct loop *loop, im_mem_ref *ref, bool stored_p)
{
stored_p |= (ref->stored && bitmap_bit_p (ref->stored, loop->num));
- if (loop->safelen > safelen
- /* Check that REF is accessed inside LOOP. */
- && (loop == ref_loop || flow_loop_nested_p (loop, ref_loop)))
- safelen = loop->safelen;
-
bool indep_p = true;
bitmap refs_to_check;
@@ -2174,32 +2167,6 @@ ref_indep_loop_p_1 (int safelen, struct
if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID))
indep_p = false;
- else if (safelen > 1)
- {
- if (dump_file && (dump_flags & TDF_DETAILS))
- {
- fprintf (dump_file,"REF is independent due to safelen %d\n",
- safelen);
- print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM);
- fprintf (dump_file, "\n");
- }
-
- /* We need to recurse to properly handle UNANALYZABLE_MEM_ID. */
- struct loop *inner = loop->inner;
- while (inner)
- {
- if (!ref_indep_loop_p_1 (safelen, inner, ref, stored_p, ref_loop))
- {
- indep_p = false;
- break;
- }
- inner = inner->next;
- }
-
- /* Avoid caching here as safelen depends on context and refs
- are shared between different contexts. */
- return indep_p;
- }
else
{
if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)))
@@ -2210,7 +2177,7 @@ ref_indep_loop_p_1 (int safelen, struct
struct loop *inner = loop->inner;
while (inner)
{
- if (!ref_indep_loop_p_1 (safelen, inner, ref, stored_p, ref_loop))
+ if (!ref_indep_loop_p_1 (inner, ref, stored_p))
{
indep_p = false;
break;
@@ -2264,14 +2231,14 @@ ref_indep_loop_p_1 (int safelen, struct
}
/* Returns true if REF is independent on all other memory references in
- LOOP. REF_LOOP is the loop where REF is accessed. */
+ LOOP. */
static bool
-ref_indep_loop_p (struct loop *loop, im_mem_ref *ref, struct loop *ref_loop)
+ref_indep_loop_p (struct loop *loop, im_mem_ref *ref)
{
gcc_checking_assert (MEM_ANALYZABLE (ref));
- return ref_indep_loop_p_1 (0, loop, ref, false, ref_loop);
+ return ref_indep_loop_p_1 (loop, ref, false);
}
/* Returns true if we can perform store motion of REF from LOOP. */
@@ -2307,7 +2274,7 @@ can_sm_ref_p (struct loop *loop, im_mem_
/* And it must be independent on all other memory references
in LOOP. */
- if (!ref_indep_loop_p (loop, ref, loop))
+ if (!ref_indep_loop_p (loop, ref))
return false;
return true;
Index: gcc/testsuite/g++.dg/torture/pr81877.C
===================================================================
--- gcc/testsuite/g++.dg/torture/pr81877.C (nonexistent)
+++ gcc/testsuite/g++.dg/torture/pr81877.C (working copy)
@@ -0,0 +1,22 @@
+/* { dg-do run } */
+
+void __attribute__((noipa)) g(int p, int *out)
+{
+ int x = 0, y;
+#pragma GCC ivdep
+ for (int i = 0; i < 100; i++)
+ {
+ int &r = p ? x : y;
+ r = 42;
+ out[i] = x;
+ }
+}
+
+int main()
+{
+ int out[100] = { 0 };
+ g (1, out);
+ if (out[0] != 42)
+ __builtin_abort ();
+ return 0;
+}
Index: gcc/testsuite/g++.dg/vect/pr70729-nest.cc
===================================================================
--- gcc/testsuite/g++.dg/vect/pr70729-nest.cc (revision 255684)
+++ gcc/testsuite/g++.dg/vect/pr70729-nest.cc (working copy)
@@ -76,4 +76,4 @@ void Ss::foo (int n)
}
}
-// { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" { target x86_64-*-*
i?86-*-* } } }
+// { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" { xfail *-*-* } } }
Index: gcc/testsuite/g++.dg/vect/pr70729.cc
===================================================================
--- gcc/testsuite/g++.dg/vect/pr70729.cc (revision 255684)
+++ gcc/testsuite/g++.dg/vect/pr70729.cc (working copy)
@@ -70,4 +70,4 @@ void Ss::foo (float *in, float w)
}
}
-// { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" { target x86_64-*-*
i?86-*-* } } }
+// { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" { xfail *-*-* } } }
