Hi!
MEM_REFs which can represent type punning on lhs don't force
non-gimple types to be addressable. This causes various problems
in the expander, which wasn't prepared to handle that.
This patch tries to fix what I've found and adds a bunch of
testcases. The original report was with just -O2 on some large testcase
from Eigen, most of the testcases have -fno-tree-sra just because
I've given up on delta when it stopped reducing at 32KB.
The first problem (the one from Eigen) is _mm_store_pd into
a std::complex<double> var, which is a single field and thus
has DCmode TYPE_MODE. As starting with 4.6 that var is not
TREE_ADDRESSABLE, its DECL_RTL is a CONCAT, and for assignments
to concat expand_assignment was expecting either that
from has COMPLEX_TYPE (and matching mode to the store), or
that it is a real or imaginary subpart store, thus when
trying to store a V2DF mode value it expected it to be
real part store (bitpos == 0) and tried to set a DFmode pseudo
from V2DFmode rtx.
Further testing revealed that it is possible to hit many other
cases with CONCAT destination, it can be a store of just a few bits,
or can overlap parts of both real and imaginary, or be partially
out of bounds.
The patch handles the case from Eigen - bitpos == 0 bitsize ==
GET_MODE_BITSIZE (GET_MODE (to_rtx)) non-COMPLEX_TYPE by setting
each half separately, if it is a store which is not touching
one of the parts by just adjusting bitpos for the imaginary
case and storing just to one of the parts (this is
the bitpos + bitsize < half_bitsize resp. bitpos >= half_bitsize
case) and finally adds a generic slow one for the very unusual
cases with partial overlap of both.
After testing it with the testcases I wrote, I found a bunch of
other ICEs though, and reproduced them even without CONCAT
on the LHS (the testcases below which don't contain any _Complex
keyword).
Bootstrapped/regtested on x86_64-linux and i686-linux,
regtested with a cross compiler on these new testcases also
for powerpc{,64}-linux and s390{,x}-linux.
Ok for trunk and after a while for 4.6?
2011-03-30 Jakub Jelinek <ja...@redhat.com>
PR middle-end/48335
* expr.c (expand_assignment): Handle all possibilities
if TO_RTX is CONCAT.
* expmed.c (store_bit_field_1): Avoid trying to create
invalid SUBREGs.
(store_split_bit_field): If SUBREG_REG (op0) or
op0 itself has smaller mode than word, return it
for offset 0 and const0_rtx for out of bounds stores.
If word is const0_rtx, skip it.
* gcc.c-torture/compile/pr48335-1.c: New test.
* gcc.dg/pr48335-1.c: New test.
* gcc.dg/pr48335-2.c: New test.
* gcc.dg/pr48335-3.c: New test.
* gcc.dg/pr48335-4.c: New test.
* gcc.dg/pr48335-5.c: New test.
* gcc.dg/pr48335-6.c: New test.
* gcc.dg/pr48335-7.c: New test.
* gcc.dg/pr48335-8.c: New test.
* gcc.target/i386/pr48335-1.c: New test.
--- gcc/expr.c.jj 2011-03-23 17:15:55.000000000 +0100
+++ gcc/expr.c 2011-03-30 11:38:15.000000000 +0200
@@ -4278,16 +4278,47 @@ expand_assignment (tree to, tree from, b
/* Handle expand_expr of a complex value returning a CONCAT. */
else if (GET_CODE (to_rtx) == CONCAT)
{
- if (COMPLEX_MODE_P (TYPE_MODE (TREE_TYPE (from))))
+ unsigned short mode_bitsize = GET_MODE_BITSIZE (GET_MODE (to_rtx));
+ if (COMPLEX_MODE_P (TYPE_MODE (TREE_TYPE (from)))
+ && bitpos == 0
+ && bitsize == mode_bitsize)
+ result = store_expr (from, to_rtx, false, nontemporal);
+ else if (bitsize == mode_bitsize / 2
+ && (bitpos == 0 || bitpos == GET_MODE_BITSIZE (mode1)))
+ result = store_expr (from, XEXP (to_rtx, bitpos != 0), false,
+ nontemporal);
+ else if (bitpos + bitsize <= mode_bitsize / 2)
+ result = store_field (XEXP (to_rtx, 0), bitsize, bitpos,
+ mode1, from, TREE_TYPE (tem),
+ get_alias_set (to), nontemporal);
+ else if (bitpos >= mode_bitsize / 2)
+ result = store_field (XEXP (to_rtx, 1), bitsize,
+ bitpos - mode_bitsize / 2, mode1, from,
+ TREE_TYPE (tem), get_alias_set (to),
+ nontemporal);
+ else if (bitpos == 0 && bitsize == mode_bitsize)
{
- gcc_assert (bitpos == 0);
- result = store_expr (from, to_rtx, false, nontemporal);
+ rtx from_rtx = expand_normal (from);
+ from_rtx = simplify_gen_subreg (GET_MODE (to_rtx), from_rtx,
+ TYPE_MODE (TREE_TYPE (from)), 0);
+ emit_move_insn (XEXP (to_rtx, 0),
+ read_complex_part (from_rtx, false));
+ emit_move_insn (XEXP (to_rtx, 1),
+ read_complex_part (from_rtx, true));
+ result = NULL;
}
else
{
- gcc_assert (bitpos == 0 || bitpos == GET_MODE_BITSIZE (mode1));
- result = store_expr (from, XEXP (to_rtx, bitpos != 0), false,
- nontemporal);
+ rtx temp = assign_stack_temp (GET_MODE (to_rtx),
+ GET_MODE_SIZE (GET_MODE (to_rtx)),
+ 0);
+ write_complex_part (temp, XEXP (to_rtx, 0), false);
+ write_complex_part (temp, XEXP (to_rtx, 1), true);
+ result = store_field (temp, bitsize, bitpos, mode1, from,
+ TREE_TYPE (tem), get_alias_set (to),
+ nontemporal);
+ emit_move_insn (XEXP (to_rtx, 0), read_complex_part (temp,
false));
+ emit_move_insn (XEXP (to_rtx, 1), read_complex_part (temp, true));
}
}
else
--- gcc/expmed.c.jj 2011-03-23 17:15:55.000000000 +0100
+++ gcc/expmed.c 2011-03-30 13:37:54.000000000 +0200
@@ -422,7 +422,10 @@ store_bit_field_1 (rtx str_rtx, unsigned
&& byte_offset % GET_MODE_SIZE (fieldmode) == 0)
: (! SLOW_UNALIGNED_ACCESS (fieldmode, MEM_ALIGN (op0))
|| (offset * BITS_PER_UNIT % bitsize == 0
- && MEM_ALIGN (op0) % GET_MODE_BITSIZE (fieldmode) == 0))))
+ && MEM_ALIGN (op0) % GET_MODE_BITSIZE (fieldmode) == 0)))
+ && (MEM_P (op0)
+ || GET_MODE (op0) == fieldmode
+ || validate_subreg (fieldmode, GET_MODE (op0), op0, byte_offset)))
{
if (MEM_P (op0))
op0 = adjust_address (op0, fieldmode, offset);
@@ -479,6 +482,7 @@ store_bit_field_1 (rtx str_rtx, unsigned
struct expand_operand ops[2];
enum insn_code icode = optab_handler (movstrict_optab, fieldmode);
rtx arg0 = op0;
+ unsigned HOST_WIDE_INT subreg_off;
if (GET_CODE (arg0) == SUBREG)
{
@@ -491,15 +495,18 @@ store_bit_field_1 (rtx str_rtx, unsigned
arg0 = SUBREG_REG (arg0);
}
- arg0 = gen_rtx_SUBREG (fieldmode, arg0,
- (bitnum % BITS_PER_WORD) / BITS_PER_UNIT
- + (offset * UNITS_PER_WORD));
-
- create_fixed_operand (&ops[0], arg0);
- /* Shrink the source operand to FIELDMODE. */
- create_convert_operand_to (&ops[1], value, fieldmode, false);
- if (maybe_expand_insn (icode, 2, ops))
- return true;
+ subreg_off = (bitnum % BITS_PER_WORD) / BITS_PER_UNIT
+ + (offset * UNITS_PER_WORD);
+ if (validate_subreg (fieldmode, GET_MODE (arg0), arg0, subreg_off))
+ {
+ arg0 = gen_rtx_SUBREG (fieldmode, arg0, subreg_off);
+
+ create_fixed_operand (&ops[0], arg0);
+ /* Shrink the source operand to FIELDMODE. */
+ create_convert_operand_to (&ops[1], value, fieldmode, false);
+ if (maybe_expand_insn (icode, 2, ops))
+ return true;
+ }
}
/* Handle fields bigger than a word. */
@@ -1045,22 +1052,32 @@ store_split_bit_field (rtx op0, unsigned
if (GET_CODE (op0) == SUBREG)
{
int word_offset = (SUBREG_BYTE (op0) / UNITS_PER_WORD) + offset;
- word = operand_subword_force (SUBREG_REG (op0), word_offset,
- GET_MODE (SUBREG_REG (op0)));
+ enum machine_mode sub_mode = GET_MODE (SUBREG_REG (op0));
+ if (sub_mode != BLKmode && GET_MODE_SIZE (sub_mode) < UNITS_PER_WORD)
+ word = word_offset ? const0_rtx : op0;
+ else
+ word = operand_subword_force (SUBREG_REG (op0), word_offset,
+ GET_MODE (SUBREG_REG (op0)));
offset = 0;
}
else if (REG_P (op0))
{
- word = operand_subword_force (op0, offset, GET_MODE (op0));
+ enum machine_mode op0_mode = GET_MODE (op0);
+ if (op0_mode != BLKmode && GET_MODE_SIZE (op0_mode) < UNITS_PER_WORD)
+ word = offset ? const0_rtx : op0;
+ else
+ word = operand_subword_force (op0, offset, GET_MODE (op0));
offset = 0;
}
else
word = op0;
/* OFFSET is in UNITs, and UNIT is in bits.
- store_fixed_bit_field wants offset in bytes. */
- store_fixed_bit_field (word, offset * unit / BITS_PER_UNIT, thissize,
- thispos, part);
+ store_fixed_bit_field wants offset in bytes. If WORD is const0_rtx,
+ it is jut an out of bounds access. Ignore it. */
+ if (word != const0_rtx)
+ store_fixed_bit_field (word, offset * unit / BITS_PER_UNIT, thissize,
+ thispos, part);
bitsdone += thissize;
}
}
--- gcc/testsuite/gcc.c-torture/compile/pr48335-1.c.jj 2011-03-30
11:32:24.000000000 +0200
+++ gcc/testsuite/gcc.c-torture/compile/pr48335-1.c 2011-03-30
11:31:47.000000000 +0200
@@ -0,0 +1,41 @@
+/* PR middle-end/48335 */
+
+struct S { float d; };
+
+void bar (struct S);
+
+void
+f0 (int x)
+{
+ struct S s = {.d = 0.0f };
+ ((char *) &s.d)[0] = x;
+ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f1 (int x)
+{
+ struct S s = {.d = 0.0f };
+ ((char *) &s.d)[1] = x;
+ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (int x)
+{
+ struct S s = {.d = 0.0f };
+ ((char *) &s.d)[2] = x;
+ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f3 (int x)
+{
+ struct S s = {.d = 0.0f };
+ ((char *) &s.d)[3] = x;
+ s.d *= 7.0;
+ bar (s);
+}
--- gcc/testsuite/gcc.dg/pr48335-1.c.jj 2011-03-30 10:57:29.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-1.c 2011-03-29 18:28:03.000000000 +0200
@@ -0,0 +1,48 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef long long T __attribute__((may_alias));
+
+struct S
+{
+ _Complex float d __attribute__((aligned (8)));
+};
+
+void bar (struct S);
+
+void
+f1 (T x)
+{
+ struct S s;
+ *(T *) &s.d = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (int x)
+{
+ struct S s = { .d = 0.0f };
+ *(char *) &s.d = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f3 (int x)
+{
+ struct S s = { .d = 0.0f };
+ ((char *) &s.d)[2] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f4 (int x, int y)
+{
+ struct S s = { .d = 0.0f };
+ ((char *) &s.d)[y] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
--- gcc/testsuite/gcc.dg/pr48335-2.c.jj 2011-03-30 10:57:29.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-2.c 2011-03-29 18:27:53.000000000 +0200
@@ -0,0 +1,58 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef long long T __attribute__((may_alias, aligned (1)));
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ _Complex float d __attribute__((aligned (8)));
+};
+
+void bar (struct S);
+
+void
+f1 (T x)
+{
+ struct S s;
+ *(T *) ((char *) &s.d + 1) = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (int x)
+{
+ struct S s = { .d = 0.0f };
+ ((U *)((char *) &s.d + 1))[0] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f3 (int x)
+{
+ struct S s = { .d = 0.0f };
+ ((U *)((char *) &s.d + 1))[1] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f4 (int x)
+{
+ struct S s = { .d = 0.0f };
+ ((U *)((char *) &s.d + 1))[2] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f5 (int x)
+{
+ struct S s = { .d = 0.0f };
+ ((U *)((char *) &s.d + 1))[3] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
--- gcc/testsuite/gcc.dg/pr48335-3.c.jj 2011-03-30 11:43:38.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-3.c 2011-03-30 11:42:54.000000000 +0200
@@ -0,0 +1,48 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ double d;
+};
+
+void bar (struct S);
+
+void
+f1 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[0] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[1] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f3 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[2] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f4 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[3] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
--- gcc/testsuite/gcc.dg/pr48335-4.c.jj 2011-03-30 12:59:11.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-4.c 2011-03-30 12:55:51.000000000 +0200
@@ -0,0 +1,39 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ double d;
+};
+
+void bar (struct S);
+
+void
+f1 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[-1] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[-2] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f3 (int x)
+{
+ struct S s = { .d = 0.0 };
+ ((U *)((char *) &s.d + 1))[5] = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
--- gcc/testsuite/gcc.dg/pr48335-5.c.jj 2011-03-30 13:09:30.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-5.c 2011-03-30 13:01:10.000000000 +0200
@@ -0,0 +1,38 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef long long T __attribute__((may_alias));
+
+struct S
+{
+ _Complex float d __attribute__((aligned (8)));
+};
+
+int
+f1 (struct S x)
+{
+ struct S s = x;
+ return *(T *) &s.d;
+}
+
+int
+f2 (struct S x)
+{
+ struct S s = x;
+ return *(char *) &s.d;
+}
+
+int
+f3 (struct S x)
+{
+ struct S s = x;
+ return ((char *) &s.d)[2];
+}
+
+int
+f4 (struct S x, int y)
+{
+ struct S s = x;
+ return ((char *) &s.d)[y];
+}
--- gcc/testsuite/gcc.dg/pr48335-6.c.jj 2011-03-30 13:09:30.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-6.c 2011-03-30 13:04:58.000000000 +0200
@@ -0,0 +1,46 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef long long T __attribute__((may_alias, aligned (1)));
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ _Complex float d __attribute__((aligned (8)));
+};
+
+T
+f1 (struct S x)
+{
+ struct S s = x;
+ return *(T *) ((char *) &s.d + 1);
+}
+
+int
+f2 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[0];
+}
+
+int
+f3 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[1];
+}
+
+int
+f4 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[2];
+}
+
+int
+f5 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[3];
+}
--- gcc/testsuite/gcc.dg/pr48335-7.c.jj 2011-03-30 13:09:30.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-7.c 2011-03-30 13:07:17.000000000 +0200
@@ -0,0 +1,38 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ double d;
+};
+
+int
+f1 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[0];
+}
+
+int
+f2 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[1];
+}
+
+int
+f3 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[2];
+}
+
+int
+f4 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[3];
+}
--- gcc/testsuite/gcc.dg/pr48335-8.c.jj 2011-03-30 13:09:30.000000000 +0200
+++ gcc/testsuite/gcc.dg/pr48335-8.c 2011-03-30 13:08:17.000000000 +0200
@@ -0,0 +1,31 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra" } */
+
+typedef short U __attribute__((may_alias, aligned (1)));
+
+struct S
+{
+ double d;
+};
+
+int
+f1 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[-1];
+}
+
+int
+f2 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[-2];
+}
+
+int
+f3 (struct S x)
+{
+ struct S s = x;
+ return ((U *)((char *) &s.d + 1))[5];
+}
--- gcc/testsuite/gcc.target/i386/pr48335-1.c.jj 2011-03-30
10:57:16.000000000 +0200
+++ gcc/testsuite/gcc.target/i386/pr48335-1.c 2011-03-29 18:28:12.000000000
+0200
@@ -0,0 +1,32 @@
+/* PR middle-end/48335 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-sra -msse2" } */
+
+#include <emmintrin.h>
+
+typedef __float128 T __attribute__((may_alias));
+
+struct S
+{
+ _Complex double d __attribute__((aligned (16)));
+};
+
+void bar (struct S);
+
+void
+f1 (T x)
+{
+ struct S s;
+ *(T *) &s.d = x;
+ __real__ s.d *= 7.0;
+ bar (s);
+}
+
+void
+f2 (__m128d x)
+{
+ struct S s;
+ _mm_store_pd ((double *) &s.d, x);
+ __real__ s.d *= 7.0;
+ bar (s);
+}
Jakub
