Hello,
On Sun, Mar 10 2019, Martin Jambor wrote:
> Hi,
>
> after we have accidentally dropped the mailing list from our discussion
> (my apologies for not spotting that in time), Richi has approved the
> following patch which I have bootstrapped and tested on x86_64-linux
> (all languages) and on i686-linux, aarch64-linux and ppc64-linux (C, C++
> and Fortran) and so I am about to commit it to trunk.
>
> It XFAILS three guality tests which pass at -O0, which means there are
> three additional XPASSes - there already are 5 pre-existing XPASSes in
> that testcase and 29 outright failures. I will come back to this next
> in April and see whether I can make the tests pass by decoupling the
> roles now played by cannot_scalarize_away_bitmap (or at least massage
> the testcase to go make the XPASSes go away). But I won't have time to
> do it next two weeks and this patch is important enough to have it in
> trunk now. I intend to backport it to gcc 8 in April too.
>
> Thanks,
>
> Martin
>
>
> 2019-03-08 Martin Jambor <mjam...@suse.cz>
>
> PR tree-optimization/85762
> PR tree-optimization/87008
> PR tree-optimization/85459
> * tree-sra.c (contains_vce_or_bfcref_p): New parameter, set the bool
> it points to if there is a type changing MEM_REF. Adjust all callers.
> (build_accesses_from_assign): Disable total scalarization if
> contains_vce_or_bfcref_p returns true through the new parameter, for
> both rhs and lhs.
>
> testsuite/
> * g++.dg/tree-ssa/pr87008.C: New test.
> * gcc.dg/guality/pr54970.c: Xfail tests querying a[0] everywhere.
this patch has been on trunk for over a month and at least so far nobody
complained. I have applied it to gcc-8-branch and did a bootstrap and
testing on an x86_64-linux machine and there were no problems either.
Therefore I would propose to backport it - the other option being leaving
the gcc 8 regression(s) unfixed. What do you think?
Martin
2019-04-16 Martin Jambor <mjam...@suse.cz>
Backport from mainline
2019-03-10 Martin Jambor <mjam...@suse.cz>
PR tree-optimization/85762
PR tree-optimization/87008
PR tree-optimization/85459
* tree-sra.c (contains_vce_or_bfcref_p): New parameter, set the bool
it points to if there is a type changing MEM_REF. Adjust all callers.
(build_accesses_from_assign): Disable total scalarization if
contains_vce_or_bfcref_p returns true through the new parameter, for
both rhs and lhs.
testsuite/
* g++.dg/tree-ssa/pr87008.C: New test.
* gcc.dg/guality/pr54970.c: Xfail tests querying a[0] everywhere.
---
gcc/testsuite/g++.dg/tree-ssa/pr87008.C | 17 ++++++++++++
gcc/testsuite/gcc.dg/guality/pr54970.c | 6 ++---
gcc/tree-sra.c | 36 ++++++++++++++++++-------
3 files changed, 47 insertions(+), 12 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/tree-ssa/pr87008.C
diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr87008.C
b/gcc/testsuite/g++.dg/tree-ssa/pr87008.C
new file mode 100644
index 00000000000..eef521f9ad5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tree-ssa/pr87008.C
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+extern void dontcallthis();
+
+struct A { long a, b; };
+struct B : A {};
+template<class T>void cp(T&a,T const&b){a=b;}
+long f(B x){
+ B y; cp<A>(y,x);
+ B z; cp<A>(z,x);
+ if (y.a - z.a)
+ dontcallthis ();
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump-not "dontcallthis" "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/guality/pr54970.c
b/gcc/testsuite/gcc.dg/guality/pr54970.c
index 1819d023e21..f12a9aac1d2 100644
--- a/gcc/testsuite/gcc.dg/guality/pr54970.c
+++ b/gcc/testsuite/gcc.dg/guality/pr54970.c
@@ -8,17 +8,17 @@
int
main ()
{
- int a[] = { 1, 2, 3 }; /* { dg-final { gdb-test 15 "a\[0\]" "1" } } */
+ int a[] = { 1, 2, 3 }; /* { dg-final { gdb-test 15 "a\[0\]" "1" {
xfail { *-*-* } } } } */
int *p = a + 2; /* { dg-final { gdb-test 15 "a\[1\]" "2" } } */
int *q = a + 1; /* { dg-final { gdb-test 15 "a\[2\]" "3" } } */
/* { dg-final { gdb-test 15 "*p" "3" } } */
asm volatile (NOP); /* { dg-final { gdb-test 15 "*q" "2" } } */
- *p += 10; /* { dg-final { gdb-test 20 "a\[0\]" "1" } } */
+ *p += 10; /* { dg-final { gdb-test 20 "a\[0\]" "1" {
xfail { *-*-* } } } } */
/* { dg-final { gdb-test 20 "a\[1\]" "2" } } */
/* { dg-final { gdb-test 20 "a\[2\]" "13" } } */
/* { dg-final { gdb-test 20 "*p" "13" } } */
asm volatile (NOP); /* { dg-final { gdb-test 20 "*q" "2" } } */
- *q += 10; /* { dg-final { gdb-test 25 "a\[0\]" "1" } } */
+ *q += 10; /* { dg-final { gdb-test 25 "a\[0\]" "1" {
xfail { *-*-* } } } } */
/* { dg-final { gdb-test 25 "a\[1\]" "12" } } */
/* { dg-final { gdb-test 25 "a\[2\]" "13" } } */
/* { dg-final { gdb-test 25 "*p" "13" } } */
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index bb373b33b7a..e1ebdfaa225 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -1150,29 +1150,36 @@ contains_view_convert_expr_p (const_tree ref)
return false;
}
-/* Return true if REF contains a VIEW_CONVERT_EXPR or a MEM_REF that performs
- type conversion or a COMPONENT_REF with a bit-field field declaration. */
+/* Return true if REF contains a VIEW_CONVERT_EXPR or a COMPONENT_REF with a
+ bit-field field declaration. If TYPE_CHANGING_P is non-NULL, set the bool
+ it points to will be set if REF contains any of the above or a MEM_REF
+ expression that effectively performs type conversion. */
static bool
-contains_vce_or_bfcref_p (const_tree ref)
+contains_vce_or_bfcref_p (const_tree ref, bool *type_changing_p = NULL)
{
while (handled_component_p (ref))
{
if (TREE_CODE (ref) == VIEW_CONVERT_EXPR
|| (TREE_CODE (ref) == COMPONENT_REF
&& DECL_BIT_FIELD (TREE_OPERAND (ref, 1))))
- return true;
+ {
+ if (type_changing_p)
+ *type_changing_p = true;
+ return true;
+ }
ref = TREE_OPERAND (ref, 0);
}
- if (TREE_CODE (ref) != MEM_REF
+ if (!type_changing_p
+ || TREE_CODE (ref) != MEM_REF
|| TREE_CODE (TREE_OPERAND (ref, 0)) != ADDR_EXPR)
return false;
tree mem = TREE_OPERAND (TREE_OPERAND (ref, 0), 0);
if (TYPE_MAIN_VARIANT (TREE_TYPE (ref))
!= TYPE_MAIN_VARIANT (TREE_TYPE (mem)))
- return true;
+ *type_changing_p = true;
return false;
}
@@ -1368,15 +1375,26 @@ build_accesses_from_assign (gimple *stmt)
lacc->grp_assignment_write = 1;
if (storage_order_barrier_p (rhs))
lacc->grp_unscalarizable_region = 1;
+
+ if (should_scalarize_away_bitmap && !is_gimple_reg_type (lacc->type))
+ {
+ bool type_changing_p = false;
+ contains_vce_or_bfcref_p (lhs, &type_changing_p);
+ if (type_changing_p)
+ bitmap_set_bit (cannot_scalarize_away_bitmap,
+ DECL_UID (lacc->base));
+ }
}
if (racc)
{
racc->grp_assignment_read = 1;
- if (should_scalarize_away_bitmap && !gimple_has_volatile_ops (stmt)
- && !is_gimple_reg_type (racc->type))
+ if (should_scalarize_away_bitmap && !is_gimple_reg_type (racc->type))
{
- if (contains_vce_or_bfcref_p (rhs))
+ bool type_changing_p = false;
+ contains_vce_or_bfcref_p (rhs, &type_changing_p);
+
+ if (type_changing_p || gimple_has_volatile_ops (stmt))
bitmap_set_bit (cannot_scalarize_away_bitmap,
DECL_UID (racc->base));
else
--
2.21.0
