This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH, RFC] PR 55415 : Pessimistic misalignment from eipa_sra pass
On Thu, Nov 29, 2012 at 11:06:41AM +0100, Martin Jambor wrote:
> Hi,
>
> thanks for the review. When writing a reply I realized I indeed made
> a mistake or two in the part concerning prev_base and the code was not
> what it intended to be. I'll re-write it today.
OK, this is it. The part in tree-sra.c, in which I make IPA-SRA punt
when the alignment of the loads in the callee are not as big as
alignment of the required types of the new arguments, remained the
same.
In ipa-prop.h, I now use maximum of the alignment from
get_pointer_alignment_1 and the type alignment propagated from the
callee. I now also recognize cases where the dereference is buried
below a COMPONENT_REF or ARRAY_REF (this is checked by new testcase
ipa-sra-9.c which fails at least on on sparc64 when things go wrong).
The patch has passed bootstrap and testing on x86_64-linux,
ppc64-linux and sparc64-linux.
Thanks,
Martin
2012-11-29 Martin Jambor <mjambor@suse.cz>
PR middle-end/52890
PR tree-optimization/55415
PR tree-optimization/54386
PR target/55448
* ipa-prop.c (ipa_modify_call_arguments): Be optimistic when
get_pointer_alignment_1 returns false and the base was not a
dereference.
* tree-sra.c (access_precludes_ipa_sra_p): New parameter req_align,
added check for required alignment. Update the user.
* testsuite/gcc.dg/ipa/ipa-sra-7.c: New test.
* testsuite/gcc.dg/ipa/ipa-sra-8.c: Likewise.
* testsuite/gcc.dg/ipa/ipa-sra-9.c: Likewise.
* testsuite/gcc.target/i386/pr55448.c: Likewise.
*** /tmp/cY007b_ipa-prop.c Fri Nov 30 12:26:26 2012
--- gcc/ipa-prop.c Thu Nov 29 16:05:04 2012
*************** ipa_modify_call_arguments (struct cgraph
*** 2888,2893 ****
--- 2888,2895 ----
{
tree expr, base, off;
location_t loc;
+ unsigned int deref_align;
+ bool deref_base = false;
/* We create a new parameter out of the value of the old one, we can
do the following kind of transformations:
*************** ipa_modify_call_arguments (struct cgraph
*** 2920,2928 ****
{
HOST_WIDE_INT base_offset;
tree prev_base;
if (TREE_CODE (base) == ADDR_EXPR)
! base = TREE_OPERAND (base, 0);
prev_base = base;
base = get_addr_base_and_unit_offset (base, &base_offset);
/* Aggregate arguments can have non-invariant addresses. */
--- 2922,2936 ----
{
HOST_WIDE_INT base_offset;
tree prev_base;
+ bool addrof;
if (TREE_CODE (base) == ADDR_EXPR)
! {
! base = TREE_OPERAND (base, 0);
! addrof = true;
! }
! else
! addrof = false;
prev_base = base;
base = get_addr_base_and_unit_offset (base, &base_offset);
/* Aggregate arguments can have non-invariant addresses. */
*************** ipa_modify_call_arguments (struct cgraph
*** 2934,2939 ****
--- 2942,2952 ----
}
else if (TREE_CODE (base) == MEM_REF)
{
+ if (!addrof)
+ {
+ deref_base = true;
+ deref_align = TYPE_ALIGN (TREE_TYPE (base));
+ }
off = build_int_cst (adj->alias_ptr_type,
base_offset
+ adj->offset / BITS_PER_UNIT);
*************** ipa_modify_call_arguments (struct cgraph
*** 2956,2962 ****
unsigned int align;
unsigned HOST_WIDE_INT misalign;
! get_pointer_alignment_1 (base, &align, &misalign);
misalign += (tree_to_double_int (off)
.sext (TYPE_PRECISION (TREE_TYPE (off))).low
* BITS_PER_UNIT);
--- 2969,2985 ----
unsigned int align;
unsigned HOST_WIDE_INT misalign;
! if (deref_base)
! {
! align = deref_align;
! misalign = 0;
! }
! else
! {
! get_pointer_alignment_1 (base, &align, &misalign);
! if (TYPE_ALIGN (type) > align)
! align = TYPE_ALIGN (type);
! }
misalign += (tree_to_double_int (off)
.sext (TYPE_PRECISION (TREE_TYPE (off))).low
* BITS_PER_UNIT);
*** /dev/null Thu Oct 25 13:49:30 2012
--- gcc/testsuite/gcc.dg/ipa/ipa-sra-7.c Wed Nov 28 14:19:30 2012
***************
*** 0 ****
--- 1,42 ----
+ /* { dg-do run } */
+ /* { dg-options "-O3" } */
+
+ typedef unsigned int myint __attribute__((aligned(1)));
+
+ typedef struct __attribute__((packed)) S {
+ unsigned a, b, c;
+ } SS;
+
+ typedef SS __attribute__((aligned(1))) SSS;
+
+
+ static unsigned int __attribute__ ((noinline))
+ get_a (SSS *p)
+ {
+ return p->a;
+ };
+
+ static int __attribute__ ((noinline, noclone))
+ foo (SS *p)
+ {
+ int r = (int) get_a(p) + 2;
+ return r;
+ }
+
+ char buf[512];
+
+ static SSS * __attribute__ ((noinline, noclone))
+ get_sss (void)
+ {
+ return (SSS *)(buf + 1);
+ }
+
+
+ int
+ main(int argc, char *argv[])
+ {
+ SSS *p = get_sss();
+ if (foo(p) != 2)
+ __builtin_abort ();
+ return 0;
+ }
*** /dev/null Thu Oct 25 13:49:30 2012
--- gcc/testsuite/gcc.dg/ipa/ipa-sra-8.c Fri Nov 30 00:52:03 2012
***************
*** 0 ****
--- 1,41 ----
+ /* { dg-do run } */
+ /* { dg-options "-O3" } */
+
+ typedef unsigned int myint __attribute__((aligned(1)));
+
+ typedef struct S {
+ unsigned a, b, c;
+ } SS;
+
+ typedef SS __attribute__((aligned(1))) SSS;
+
+
+ static unsigned int __attribute__ ((noinline))
+ get_a (SS s)
+ {
+ return s.a;
+ };
+
+ static int __attribute__ ((noinline, noclone))
+ foo (SSS *p)
+ {
+ int r = (int) get_a(*p) + 2;
+ return r;
+ }
+
+ char buf[512];
+
+ static SSS * __attribute__ ((noinline, noclone))
+ get_sss (void)
+ {
+ return (SSS *)(buf + 1);
+ }
+
+ int
+ main(int argc, char *argv[])
+ {
+ SSS *p = get_sss();
+ if (foo(p) != 2)
+ __builtin_abort ();
+ return 0;
+ }
*** /dev/null Thu Oct 25 13:49:30 2012
--- gcc/testsuite/gcc.dg/ipa/ipa-sra-9.c Fri Nov 30 00:52:12 2012
***************
*** 0 ****
--- 1,44 ----
+ /* { dg-do run } */
+ /* { dg-options "-O3" } */
+
+ typedef unsigned int myint __attribute__((aligned(1)));
+
+ typedef struct S {
+ unsigned a, b, c;
+ } SS;
+
+ typedef struct U {
+ SS s[2];
+ } UU;
+
+ typedef UU __attribute__((aligned(1))) UUU;
+
+ static unsigned int __attribute__ ((noinline))
+ get_a (SS s)
+ {
+ return s.a;
+ };
+
+ static int __attribute__ ((noinline, noclone))
+ foo (UUU *p)
+ {
+ int r = (int) get_a(p->s[0]) + 2;
+ return r;
+ }
+
+ char buf[512];
+
+ static UUU * __attribute__ ((noinline, noclone))
+ get_uuu (void)
+ {
+ return (UUU *)(buf + 1);
+ }
+
+ int
+ main(int argc, char *argv[])
+ {
+ UUU *p = get_uuu();
+ if (foo(p) != 2)
+ __builtin_abort ();
+ return 0;
+ }
*** /dev/null Thu Oct 25 13:49:30 2012
--- gcc/testsuite/gcc.target/i386/pr55448.c Thu Nov 29 15:42:16 2012
***************
*** 0 ****
--- 1,26 ----
+ /* { dg-do compile } */
+ /* { dg-options "-O2 -mavx" } */
+
+ #include <immintrin.h>
+
+ static inline __m256 add1(const __m256 *a, const __m256 *b)
+ {
+ return _mm256_add_ps(*a, *b);
+ }
+
+ void foo1(__m256 *a, const __m256 b)
+ {
+ *a = add1(a, &b);
+ }
+
+ static inline __m128 add2(const __m128 *a, const __m128 *b)
+ {
+ return _mm_add_ps(*a, *b);
+ }
+
+ void foo2(__m128 *a, const __m128 b)
+ {
+ *a = add2(a, &b);
+ }
+
+ /* { dg-final { scan-assembler-not "vmovups" } } */
*** /tmp/yTaOsa_tree-sra.c Fri Nov 30 12:26:26 2012
--- gcc/tree-sra.c Wed Nov 28 14:19:30 2012
*************** unmodified_by_ref_scalar_representative
*** 3891,3902 ****
return repr;
}
! /* Return true iff this access precludes IPA-SRA of the parameter it is
! associated with. */
static bool
! access_precludes_ipa_sra_p (struct access *access)
{
/* Avoid issues such as the second simple testcase in PR 42025. The problem
is incompatible assign in a call statement (and possibly even in asm
statements). This can be relaxed by using a new temporary but only for
--- 3891,3903 ----
return repr;
}
! /* Return true iff this ACCESS precludes IPA-SRA of the parameter it is
! associated with. REQ_ALIGN is the minimum required alignment. */
static bool
! access_precludes_ipa_sra_p (struct access *access, unsigned int req_align)
{
+ unsigned int exp_align;
/* Avoid issues such as the second simple testcase in PR 42025. The problem
is incompatible assign in a call statement (and possibly even in asm
statements). This can be relaxed by using a new temporary but only for
*************** access_precludes_ipa_sra_p (struct acces
*** 3908,3913 ****
--- 3909,3918 ----
|| gimple_code (access->stmt) == GIMPLE_ASM))
return true;
+ exp_align = get_object_alignment (access->expr);
+ if (exp_align < req_align)
+ return true;
+
return false;
}
*************** splice_param_accesses (tree parm, bool *
*** 3943,3949 ****
tree a1_alias_type;
access = (*access_vec)[i];
modification = access->write;
! if (access_precludes_ipa_sra_p (access))
return NULL;
a1_alias_type = reference_alias_ptr_type (access->expr);
--- 3948,3954 ----
tree a1_alias_type;
access = (*access_vec)[i];
modification = access->write;
! if (access_precludes_ipa_sra_p (access, TYPE_ALIGN (access->type)))
return NULL;
a1_alias_type = reference_alias_ptr_type (access->expr);
*************** splice_param_accesses (tree parm, bool *
*** 3966,3972 ****
else if (ac2->size != access->size)
return NULL;
! if (access_precludes_ipa_sra_p (ac2)
|| (ac2->type != access->type
&& (TREE_ADDRESSABLE (ac2->type)
|| TREE_ADDRESSABLE (access->type)))
--- 3971,3977 ----
else if (ac2->size != access->size)
return NULL;
! if (access_precludes_ipa_sra_p (ac2, TYPE_ALIGN (access->type))
|| (ac2->type != access->type
&& (TREE_ADDRESSABLE (ac2->type)
|| TREE_ADDRESSABLE (access->type)))