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| author | Richard Biener <rguenther@suse.de> | 2014-04-14 11:49:42 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2014-04-14 11:49:42 +0000 |
| commit | b0f1bf3681b1f835f6402538e0f6471c72a465eb (patch) | |
| tree | de7d0e7139d874aa77d18b13a0eb4a8e293771f4 | |
| parent | 727987844249aafe00ffaf7a8030564c1f731607 (diff) | |
| download | gcc-b0f1bf3681b1f835f6402538e0f6471c72a465eb.zip gcc-b0f1bf3681b1f835f6402538e0f6471c72a465eb.tar.gz gcc-b0f1bf3681b1f835f6402538e0f6471c72a465eb.tar.bz2 | |
re PR c/60819 (dse1 removing not-dead insn (aliasing issue?))
2014-04-14 Richard Biener <rguenther@suse.de>
Marc Glisse <marc.glisse@inria.fr>
PR c/60819
c-family/
* c-common.c (convert_vector_to_pointer_for_subscript): Properly
apply may-alias the scalar pointer type when applicable.
* gcc.target/i386/vec-may_alias.c: New testcase.
Co-Authored-By: Marc Glisse <marc.glisse@inria.fr>
From-SVN: r209365
| -rw-r--r-- | gcc/c-family/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/c-family/c-common.c | 15 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.target/i386/vec-may_alias.c | 25 |
4 files changed, 52 insertions, 1 deletions
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog index f510bcc..206b47b 100644 --- a/gcc/c-family/ChangeLog +++ b/gcc/c-family/ChangeLog @@ -1,3 +1,10 @@ +2014-04-14 Richard Biener <rguenther@suse.de> + Marc Glisse <marc.glisse@inria.fr> + + PR c/60819 + * c-common.c (convert_vector_to_pointer_for_subscript): Properly + apply may-alias the scalar pointer type when applicable. + 2014-04-12 Igor Zamyatin <igor.zamyatin@intel.com> PR middle-end/60467 diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c index 1d56bc0..c0e247b 100644 --- a/gcc/c-family/c-common.c +++ b/gcc/c-family/c-common.c @@ -11784,8 +11784,21 @@ convert_vector_to_pointer_for_subscript (location_t loc, c_common_mark_addressable_vec (*vecp); type = build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type)); - type = build_pointer_type (type); type1 = build_pointer_type (TREE_TYPE (*vecp)); + bool ref_all = TYPE_REF_CAN_ALIAS_ALL (type1); + if (!ref_all + && !DECL_P (*vecp)) + { + /* If the original vector isn't declared may_alias and it + isn't a bare vector look if the subscripting would + alias the vector we subscript, and if not, force ref-all. */ + alias_set_type vecset = get_alias_set (*vecp); + alias_set_type sset = get_alias_set (type); + if (!alias_sets_must_conflict_p (sset, vecset) + && !alias_set_subset_of (sset, vecset)) + ref_all = true; + } + type = build_pointer_type_for_mode (type, ptr_mode, ref_all); *vecp = build1 (ADDR_EXPR, type1, *vecp); *vecp = convert (type, *vecp); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e944a0e..3665588 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2014-04-14 Richard Biener <rguenther@suse.de> + Marc Glisse <marc.glisse@inria.fr> + + PR c/60819 + * gcc.target/i386/vec-may_alias.c: New testcase. + 2014-04-14 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> * lib/target-supports.exp diff --git a/gcc/testsuite/gcc.target/i386/vec-may_alias.c b/gcc/testsuite/gcc.target/i386/vec-may_alias.c new file mode 100644 index 0000000..e970497 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/vec-may_alias.c @@ -0,0 +1,25 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -w -Wno-abi" } */ + +typedef int v2si __attribute__ ((vector_size (8))); +typedef short v4hi __attribute__ ((vector_size (8))); +typedef short v4hia __attribute__ ((vector_size (8), may_alias)); + +__attribute__ ((noinline, noclone)) +int f (v2si A, int N) +{ return ((v4hia)A)[N]; } + +__attribute__ ((noinline, noclone)) +int g (v2si A, int N) +{ return ((v4hi)A)[N]; } + +int main() +{ + v2si x = { 0, 0 }, y = { 1, 1 }; + if (f (x, 0) || f (x, 1) || f (x, 2) || f (x, 3)) + __builtin_abort (); + if (g (y, 0) != 1 || g (y, 1) || g (y, 2) != 1 || g (y, 3)) + __builtin_abort (); + return 0; +} + |