* match.pd: Three new patterns
@ 2015-06-12 12:25 Marek Polacek
2015-06-13 10:25 ` Marc Glisse
0 siblings, 1 reply; 14+ messages in thread
From: Marek Polacek @ 2015-06-12 12:25 UTC (permalink / raw)
To: GCC Patches, Richard Biener, Marc Glisse
This patch brings three new patterns for match.pd. I think these are
rare, but it shouldn't hurt to have them.
(I suppose you'd be happier if I was moving patterns from fold-const to
match.pd. I'll work on that as well.)
Given previous discussion, I don't think there's much to say otherwise,
but I'd appreciate if someone could glance over this.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2015-06-12 Marek Polacek <polacek@redhat.com>
* match.pd ((x & y) + (x ^ y) -> x | y,
(x & y) + (x | y) -> x + y,
(x | y) - (x ^ y) -> x & y): New patterns.
* gcc.dg/fold-plus-1.c: New test.
* gcc.dg/fold-plus-2.c: New test.
* gcc.dg/fold-minus-2.c: New test.
--- gcc/match.pd
+++ gcc/match.pd
@@ -325,6 +325,21 @@ along with GCC; see the file COPYING3. If not see
(bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
(bit_xor @0 @1))
+/* (x & y) + (x ^ y) -> x | y */
+(simplify
+ (plus:c (bit_and @0 @1) (bit_xor @0 @1))
+ (bit_ior @0 @1))
+
+/* (x & y) + (x | y) -> x + y */
+(simplify
+ (plus:c (bit_and @0 @1) (bit_ior @0 @1))
+ (plus @0 @1))
+
+/* (x | y) - (x ^ y) -> x & y */
+(simplify
+ (minus (bit_ior @0 @1) (bit_xor @0 @1))
+ (bit_and @0 @1))
+
(simplify
(abs (negate @0))
(abs @0))
--- gcc/testsuite/gcc.dg/fold-plus-1.c
+++ gcc/testsuite/gcc.dg/fold-plus-1.c
@@ -0,0 +1,70 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a ^ b;
+ return tem1 + tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a ^ b;
+ return tem1 + tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b ^ a;
+ return tem1 + tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b ^ a;
+ return tem1 + tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
--- gcc/testsuite/gcc.dg/fold-plus-2.c
+++ gcc/testsuite/gcc.dg/fold-plus-2.c
@@ -0,0 +1,69 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a | b;
+ return tem1 + tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a | b;
+ return tem1 + tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b | a;
+ return tem1 + tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b | a;
+ return tem1 + tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
--- gcc/testsuite/gcc.dg/fold-minus-2.c
+++ gcc/testsuite/gcc.dg/fold-minus-2.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a ^ b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a ^ b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b ^ a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b ^ a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-12 12:25 match.pd: Three new patterns Marek Polacek
@ 2015-06-13 10:25 ` Marc Glisse
2015-06-16 13:37 ` Richard Biener
2015-06-18 15:42 ` match.pd: Three new patterns Marek Polacek
0 siblings, 2 replies; 14+ messages in thread
From: Marc Glisse @ 2015-06-13 10:25 UTC (permalink / raw)
To: Marek Polacek; +Cc: GCC Patches, Richard Biener
They look fine to me.
> +/* (x & y) + (x ^ y) -> x | y */
This also works if you replace + with | or ^.
> +/* (x | y) - (x ^ y) -> x & y */
For symmetry, you probably also want:
(x | y) - (x & y) -> x ^ y
(they both also work with ^ instead of -)
> +/* (x & y) + (x | y) -> x + y */
Again for symmetry, it seems like this comes with
x + y - (x | y) -> x & y
x + y - (x & y) -> x | y
which seem fine when overflow is undefined or wraps, but not if for
instance it saturates.
--
Marc Glisse
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-13 10:25 ` Marc Glisse
@ 2015-06-16 13:37 ` Richard Biener
2015-06-18 16:57 ` match.pd: Three new patterns (and some more) Marek Polacek
2015-06-18 15:42 ` match.pd: Three new patterns Marek Polacek
1 sibling, 1 reply; 14+ messages in thread
From: Richard Biener @ 2015-06-16 13:37 UTC (permalink / raw)
To: Marc Glisse; +Cc: Marek Polacek, GCC Patches
On Sat, 13 Jun 2015, Marc Glisse wrote:
> They look fine to me.
>
> > +/* (x & y) + (x ^ y) -> x | y */
>
> This also works if you replace + with | or ^.
>
> > +/* (x | y) - (x ^ y) -> x & y */
>
> For symmetry, you probably also want:
> (x | y) - (x & y) -> x ^ y
>
> (they both also work with ^ instead of -)
We already have
/* (x & y) ^ (x | y) -> x ^ y */
(simplify
(bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
(bit_xor @0 @1))
but of course with minus it doesn't commutate so it's hard to
merge.
> > +/* (x & y) + (x | y) -> x + y */
>
> Again for symmetry, it seems like this comes with
> x + y - (x | y) -> x & y
> x + y - (x & y) -> x | y
> which seem fine when overflow is undefined or wraps, but not if for instance
> it saturates.
Can you adjust according to Marcs comment and re-submit? If you like
you can do it as followup as well and thus the original patch is ok
as well.
Thanks,
Richard.
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-13 10:25 ` Marc Glisse
2015-06-16 13:37 ` Richard Biener
@ 2015-06-18 15:42 ` Marek Polacek
2015-06-19 15:34 ` Marek Polacek
1 sibling, 1 reply; 14+ messages in thread
From: Marek Polacek @ 2015-06-18 15:42 UTC (permalink / raw)
To: Marc Glisse; +Cc: GCC Patches, Richard Biener
On Sat, Jun 13, 2015 at 12:05:42PM +0200, Marc Glisse wrote:
> They look fine to me.
Thanks!
> >+/* (x & y) + (x ^ y) -> x | y */
>
> This also works if you replace + with | or ^.
Done.
> >+/* (x | y) - (x ^ y) -> x & y */
>
> For symmetry, you probably also want:
> (x | y) - (x & y) -> x ^ y
Done.
> (they both also work with ^ instead of -)
Done (except (x & y) ^ (x | y) -> x ^ y which we already have).
> >+/* (x & y) + (x | y) -> x + y */
>
> Again for symmetry, it seems like this comes with
> x + y - (x | y) -> x & y
> x + y - (x & y) -> x | y
> which seem fine when overflow is undefined or wraps, but not if for instance
> it saturates.
I'll leave this as a follow-up.
Testing a new patch. Thanks again.
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns (and some more)
2015-06-16 13:37 ` Richard Biener
@ 2015-06-18 16:57 ` Marek Polacek
2015-06-22 14:40 ` Richard Biener
0 siblings, 1 reply; 14+ messages in thread
From: Marek Polacek @ 2015-06-18 16:57 UTC (permalink / raw)
To: Richard Biener; +Cc: Marc Glisse, GCC Patches
On Tue, Jun 16, 2015 at 03:35:15PM +0200, Richard Biener wrote:
> We already have
>
> /* (x & y) ^ (x | y) -> x ^ y */
> (simplify
> (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
> (bit_xor @0 @1))
>
> but of course with minus it doesn't commutate so it's hard to
> merge.
Yeah :(.
> > > +/* (x & y) + (x | y) -> x + y */
> >
> > Again for symmetry, it seems like this comes with
> > x + y - (x | y) -> x & y
> > x + y - (x & y) -> x | y
> > which seem fine when overflow is undefined or wraps, but not if for instance
> > it saturates.
>
> Can you adjust according to Marcs comment and re-submit? If you like
> you can do it as followup as well and thus the original patch is ok
> as well.
Sure. This is a new version with some more patters. Thanks.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2015-06-18 Marek Polacek <polacek@redhat.com>
* match.pd ((x ^ y) ^ (x | y) -> x & y,
(x & y) + (x ^ y) -> x | y, (x & y) | (x ^ y) -> x | y,
(x & y) ^ (x ^ y) -> x | y, (x & y) + (x | y) -> x + y,
(x | y) - (x ^ y) -> x & y, (x | y) - (x & y) -> x ^ y): New patterns.
* gcc.dg/fold-ior-1.c: New test.
* gcc.dg/fold-minus-2.c: New test.
* gcc.dg/fold-minus-3.c: New test.
* gcc.dg/fold-plus-1.c: New test.
* gcc.dg/fold-plus-2.c: New test.
* gcc.dg/fold-xor-4.c: New test.
* gcc.dg/fold-xor-5.c: New test.
diff --git gcc/match.pd gcc/match.pd
index 1ab2b1c..badb80a 100644
--- gcc/match.pd
+++ gcc/match.pd
@@ -325,6 +325,34 @@ along with GCC; see the file COPYING3. If not see
(bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
(bit_xor @0 @1))
+/* (x ^ y) ^ (x | y) -> x & y */
+(simplify
+ (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
+ (bit_and @0 @1))
+
+/* (x & y) + (x ^ y) -> x | y */
+/* (x & y) | (x ^ y) -> x | y */
+/* (x & y) ^ (x ^ y) -> x | y */
+(for op (plus bit_ior bit_xor)
+ (simplify
+ (op:c (bit_and @0 @1) (bit_xor @0 @1))
+ (bit_ior @0 @1)))
+
+/* (x & y) + (x | y) -> x + y */
+(simplify
+ (plus:c (bit_and @0 @1) (bit_ior @0 @1))
+ (plus @0 @1))
+
+/* (x | y) - (x ^ y) -> x & y */
+(simplify
+ (minus (bit_ior @0 @1) (bit_xor @0 @1))
+ (bit_and @0 @1))
+
+/* (x | y) - (x & y) -> x ^ y */
+(simplify
+ (minus (bit_ior @0 @1) (bit_and @0 @1))
+ (bit_xor @0 @1))
+
(simplify
(abs (negate @0))
(abs @0))
diff --git gcc/testsuite/gcc.dg/fold-ior-1.c gcc/testsuite/gcc.dg/fold-ior-1.c
index e69de29..0358eb5 100644
--- gcc/testsuite/gcc.dg/fold-ior-1.c
+++ gcc/testsuite/gcc.dg/fold-ior-1.c
@@ -0,0 +1,69 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a ^ b;
+ return tem1 | tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a ^ b;
+ return tem1 | tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b ^ a;
+ return tem1 | tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b ^ a;
+ return tem1 | tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = a & b;
+ return tem1 | tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = a & b;
+ return tem1 | tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = b & a;
+ return tem1 | tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = b & a;
+ return tem1 | tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-minus-2.c gcc/testsuite/gcc.dg/fold-minus-2.c
index e69de29..6501f2f 100644
--- gcc/testsuite/gcc.dg/fold-minus-2.c
+++ gcc/testsuite/gcc.dg/fold-minus-2.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a ^ b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a ^ b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b ^ a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b ^ a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-minus-3.c gcc/testsuite/gcc.dg/fold-minus-3.c
index e69de29..e7adce6 100644
--- gcc/testsuite/gcc.dg/fold-minus-3.c
+++ gcc/testsuite/gcc.dg/fold-minus-3.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-plus-1.c gcc/testsuite/gcc.dg/fold-plus-1.c
index e69de29..40d6aa2 100644
--- gcc/testsuite/gcc.dg/fold-plus-1.c
+++ gcc/testsuite/gcc.dg/fold-plus-1.c
@@ -0,0 +1,70 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a ^ b;
+ return tem1 + tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a ^ b;
+ return tem1 + tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b ^ a;
+ return tem1 + tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b ^ a;
+ return tem1 + tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-plus-2.c gcc/testsuite/gcc.dg/fold-plus-2.c
index e69de29..713abf6 100644
--- gcc/testsuite/gcc.dg/fold-plus-2.c
+++ gcc/testsuite/gcc.dg/fold-plus-2.c
@@ -0,0 +1,69 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a | b;
+ return tem1 + tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a | b;
+ return tem1 + tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b | a;
+ return tem1 + tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b | a;
+ return tem1 + tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a & b;
+ return tem1 + tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b & a;
+ return tem1 + tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-xor-4.c gcc/testsuite/gcc.dg/fold-xor-4.c
index e69de29..b5a2c48 100644
--- gcc/testsuite/gcc.dg/fold-xor-4.c
+++ gcc/testsuite/gcc.dg/fold-xor-4.c
@@ -0,0 +1,69 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = a ^ b;
+ return tem1 ^ tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = a ^ b;
+ return tem1 ^ tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a & b;
+ int tem2 = b ^ a;
+ return tem1 ^ tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b & a;
+ int tem2 = b ^ a;
+ return tem1 ^ tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = a & b;
+ return tem1 ^ tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = a & b;
+ return tem1 ^ tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = b & a;
+ return tem1 ^ tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = b & a;
+ return tem1 ^ tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-xor-5.c gcc/testsuite/gcc.dg/fold-xor-5.c
index e69de29..15ee76c 100644
--- gcc/testsuite/gcc.dg/fold-xor-5.c
+++ gcc/testsuite/gcc.dg/fold-xor-5.c
@@ -0,0 +1,69 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = a ^ b;
+ return tem1 ^ tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = a ^ b;
+ return tem1 ^ tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a | b;
+ int tem2 = b ^ a;
+ return tem1 ^ tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b | a;
+ int tem2 = b ^ a;
+ return tem1 ^ tem2;
+}
+
+int
+fn5 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = a | b;
+ return tem1 ^ tem2;
+}
+
+int
+fn6 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = a | b;
+ return tem1 ^ tem2;
+}
+
+int
+fn7 (int a, int b)
+{
+ int tem1 = a ^ b;
+ int tem2 = b | a;
+ return tem1 ^ tem2;
+}
+
+int
+fn8 (int a, int b)
+{
+ int tem1 = b ^ a;
+ int tem2 = b | a;
+ return tem1 ^ tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-18 15:42 ` match.pd: Three new patterns Marek Polacek
@ 2015-06-19 15:34 ` Marek Polacek
2015-06-19 16:22 ` Marc Glisse
2015-06-22 14:54 ` Richard Biener
0 siblings, 2 replies; 14+ messages in thread
From: Marek Polacek @ 2015-06-19 15:34 UTC (permalink / raw)
To: Marc Glisse; +Cc: GCC Patches, Richard Biener
On Thu, Jun 18, 2015 at 05:41:18PM +0200, Marek Polacek wrote:
> > Again for symmetry, it seems like this comes with
> > x + y - (x | y) -> x & y
> > x + y - (x & y) -> x | y
> > which seem fine when overflow is undefined or wraps, but not if for instance
> > it saturates.
>
> I'll leave this as a follow-up.
...here.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2015-06-19 Marek Polacek <polacek@redhat.com>
* match.pd (x + y - (x | y) -> x & y,
(x + y) - (x & y) -> x | y): New patterns.
* gcc.dg/fold-minus-4.c: New test.
* gcc.dg/fold-minus-5.c: New test.
diff --git gcc/match.pd gcc/match.pd
index badb80a..61ff710 100644
--- gcc/match.pd
+++ gcc/match.pd
@@ -343,6 +343,18 @@ along with GCC; see the file COPYING3. If not see
(plus:c (bit_and @0 @1) (bit_ior @0 @1))
(plus @0 @1))
+/* x + y - (x | y) -> x & y */
+(simplify
+ (minus (plus @0 @1) (bit_ior @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
+ (bit_and @0 @1)))
+
+/* (x + y) - (x & y) -> x | y */
+(simplify
+ (minus (plus @0 @1) (bit_and @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
+ (bit_ior @0 @1)))
+
/* (x | y) - (x ^ y) -> x & y */
(simplify
(minus (bit_ior @0 @1) (bit_xor @0 @1))
diff --git gcc/testsuite/gcc.dg/fold-minus-4.c gcc/testsuite/gcc.dg/fold-minus-4.c
index e69de29..2d76b4f 100644
--- gcc/testsuite/gcc.dg/fold-minus-4.c
+++ gcc/testsuite/gcc.dg/fold-minus-4.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-minus-5.c gcc/testsuite/gcc.dg/fold-minus-5.c
index e69de29..a31e1cc 100644
--- gcc/testsuite/gcc.dg/fold-minus-5.c
+++ gcc/testsuite/gcc.dg/fold-minus-5.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-19 15:34 ` Marek Polacek
@ 2015-06-19 16:22 ` Marc Glisse
2015-06-22 19:10 ` Marek Polacek
2015-06-22 14:54 ` Richard Biener
1 sibling, 1 reply; 14+ messages in thread
From: Marc Glisse @ 2015-06-19 16:22 UTC (permalink / raw)
To: Marek Polacek; +Cc: GCC Patches, Richard Biener
On Fri, 19 Jun 2015, Marek Polacek wrote:
> +/* x + y - (x | y) -> x & y */
> +(simplify
> + (minus (plus @0 @1) (bit_ior @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> + (bit_and @0 @1)))
> +
> +/* (x + y) - (x & y) -> x | y */
> +(simplify
> + (minus (plus @0 @1) (bit_and @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> + (bit_ior @0 @1)))
It could be macroized so they are handled by the same piece of code, but
that's not important for a couple lines.
As far as I can tell, TYPE_SATURATING is for fixed point numbers only, are
we allowed to use bit_ior/bit_and on those? I never know what kind of
integers are supposed to be supported, so I would have checked
TYPE_OVERFLOW_UNDEFINED (type) || TYPE_OVERFLOW_WRAPS (type) since those
are the 2 cases where we know it is safe (for TYPE_OVERFLOW_TRAPS it is
never clear if we are supposed to preserve traps or just avoid introducing
new ones). Well, the reviewer will know, I'll shut up :-)
(I still believe that the necessity for TYPE_OVERFLOW_SANITIZED here
points to a design issue in ubsan, but it is way too late to discuss that)
It is probably not worth the trouble adding the variant:
x+(y-(x&y)) -> x|y
since it decomposes as
y-(x&y) -> y&~x
x+(y&~x) -> x|y
x+(y-(x|y)) -> x-(x&~y) -> x&y is less likely to happen because the first
transform y-(x|y) -> -(x&~y) increases the number of insns. Bah, we can't
handle everything...
--
Marc Glisse
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns (and some more)
2015-06-18 16:57 ` match.pd: Three new patterns (and some more) Marek Polacek
@ 2015-06-22 14:40 ` Richard Biener
0 siblings, 0 replies; 14+ messages in thread
From: Richard Biener @ 2015-06-22 14:40 UTC (permalink / raw)
To: Marek Polacek; +Cc: Marc Glisse, GCC Patches
On Thu, 18 Jun 2015, Marek Polacek wrote:
> On Tue, Jun 16, 2015 at 03:35:15PM +0200, Richard Biener wrote:
> > We already have
> >
> > /* (x & y) ^ (x | y) -> x ^ y */
> > (simplify
> > (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
> > (bit_xor @0 @1))
> >
> > but of course with minus it doesn't commutate so it's hard to
> > merge.
>
> Yeah :(.
>
> > > > +/* (x & y) + (x | y) -> x + y */
> > >
> > > Again for symmetry, it seems like this comes with
> > > x + y - (x | y) -> x & y
> > > x + y - (x & y) -> x | y
> > > which seem fine when overflow is undefined or wraps, but not if for instance
> > > it saturates.
> >
> > Can you adjust according to Marcs comment and re-submit? If you like
> > you can do it as followup as well and thus the original patch is ok
> > as well.
>
> Sure. This is a new version with some more patters. Thanks.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
Ok.
Thanks,
Richard.
> 2015-06-18 Marek Polacek <polacek@redhat.com>
>
> * match.pd ((x ^ y) ^ (x | y) -> x & y,
> (x & y) + (x ^ y) -> x | y, (x & y) | (x ^ y) -> x | y,
> (x & y) ^ (x ^ y) -> x | y, (x & y) + (x | y) -> x + y,
> (x | y) - (x ^ y) -> x & y, (x | y) - (x & y) -> x ^ y): New patterns.
>
> * gcc.dg/fold-ior-1.c: New test.
> * gcc.dg/fold-minus-2.c: New test.
> * gcc.dg/fold-minus-3.c: New test.
> * gcc.dg/fold-plus-1.c: New test.
> * gcc.dg/fold-plus-2.c: New test.
> * gcc.dg/fold-xor-4.c: New test.
> * gcc.dg/fold-xor-5.c: New test.
>
> diff --git gcc/match.pd gcc/match.pd
> index 1ab2b1c..badb80a 100644
> --- gcc/match.pd
> +++ gcc/match.pd
> @@ -325,6 +325,34 @@ along with GCC; see the file COPYING3. If not see
> (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
> (bit_xor @0 @1))
>
> +/* (x ^ y) ^ (x | y) -> x & y */
> +(simplify
> + (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
> + (bit_and @0 @1))
> +
> +/* (x & y) + (x ^ y) -> x | y */
> +/* (x & y) | (x ^ y) -> x | y */
> +/* (x & y) ^ (x ^ y) -> x | y */
> +(for op (plus bit_ior bit_xor)
> + (simplify
> + (op:c (bit_and @0 @1) (bit_xor @0 @1))
> + (bit_ior @0 @1)))
> +
> +/* (x & y) + (x | y) -> x + y */
> +(simplify
> + (plus:c (bit_and @0 @1) (bit_ior @0 @1))
> + (plus @0 @1))
> +
> +/* (x | y) - (x ^ y) -> x & y */
> +(simplify
> + (minus (bit_ior @0 @1) (bit_xor @0 @1))
> + (bit_and @0 @1))
> +
> +/* (x | y) - (x & y) -> x ^ y */
> +(simplify
> + (minus (bit_ior @0 @1) (bit_and @0 @1))
> + (bit_xor @0 @1))
> +
> (simplify
> (abs (negate @0))
> (abs @0))
> diff --git gcc/testsuite/gcc.dg/fold-ior-1.c gcc/testsuite/gcc.dg/fold-ior-1.c
> index e69de29..0358eb5 100644
> --- gcc/testsuite/gcc.dg/fold-ior-1.c
> +++ gcc/testsuite/gcc.dg/fold-ior-1.c
> @@ -0,0 +1,69 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = a ^ b;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = a ^ b;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = b ^ a;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = b ^ a;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn5 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = a & b;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn6 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = a & b;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn7 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = b & a;
> + return tem1 | tem2;
> +}
> +
> +int
> +fn8 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = b & a;
> + return tem1 | tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-minus-2.c gcc/testsuite/gcc.dg/fold-minus-2.c
> index e69de29..6501f2f 100644
> --- gcc/testsuite/gcc.dg/fold-minus-2.c
> +++ gcc/testsuite/gcc.dg/fold-minus-2.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = a ^ b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = a ^ b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = b ^ a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = b ^ a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-minus-3.c gcc/testsuite/gcc.dg/fold-minus-3.c
> index e69de29..e7adce6 100644
> --- gcc/testsuite/gcc.dg/fold-minus-3.c
> +++ gcc/testsuite/gcc.dg/fold-minus-3.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-plus-1.c gcc/testsuite/gcc.dg/fold-plus-1.c
> index e69de29..40d6aa2 100644
> --- gcc/testsuite/gcc.dg/fold-plus-1.c
> +++ gcc/testsuite/gcc.dg/fold-plus-1.c
> @@ -0,0 +1,70 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = a ^ b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = a ^ b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = b ^ a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = b ^ a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn5 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = a & b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn6 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = a & b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn7 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = b & a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn8 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = b & a;
> + return tem1 + tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-plus-2.c gcc/testsuite/gcc.dg/fold-plus-2.c
> index e69de29..713abf6 100644
> --- gcc/testsuite/gcc.dg/fold-plus-2.c
> +++ gcc/testsuite/gcc.dg/fold-plus-2.c
> @@ -0,0 +1,69 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = a | b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = a | b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = b | a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = b | a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn5 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = a & b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn6 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = a & b;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn7 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = b & a;
> + return tem1 + tem2;
> +}
> +
> +int
> +fn8 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = b & a;
> + return tem1 + tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-xor-4.c gcc/testsuite/gcc.dg/fold-xor-4.c
> index e69de29..b5a2c48 100644
> --- gcc/testsuite/gcc.dg/fold-xor-4.c
> +++ gcc/testsuite/gcc.dg/fold-xor-4.c
> @@ -0,0 +1,69 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = a ^ b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = a ^ b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a & b;
> + int tem2 = b ^ a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b & a;
> + int tem2 = b ^ a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn5 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = a & b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn6 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = a & b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn7 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = b & a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn8 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = b & a;
> + return tem1 ^ tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-xor-5.c gcc/testsuite/gcc.dg/fold-xor-5.c
> index e69de29..15ee76c 100644
> --- gcc/testsuite/gcc.dg/fold-xor-5.c
> +++ gcc/testsuite/gcc.dg/fold-xor-5.c
> @@ -0,0 +1,69 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = a ^ b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = a ^ b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a | b;
> + int tem2 = b ^ a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b | a;
> + int tem2 = b ^ a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn5 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = a | b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn6 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = a | b;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn7 (int a, int b)
> +{
> + int tem1 = a ^ b;
> + int tem2 = b | a;
> + return tem1 ^ tem2;
> +}
> +
> +int
> +fn8 (int a, int b)
> +{
> + int tem1 = b ^ a;
> + int tem2 = b | a;
> + return tem1 ^ tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ " "cddce1" } } */
>
>
> Marek
>
>
--
Richard Biener <rguenther@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham Norton, HRB 21284 (AG Nuernberg)
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-19 15:34 ` Marek Polacek
2015-06-19 16:22 ` Marc Glisse
@ 2015-06-22 14:54 ` Richard Biener
1 sibling, 0 replies; 14+ messages in thread
From: Richard Biener @ 2015-06-22 14:54 UTC (permalink / raw)
To: Marek Polacek; +Cc: Marc Glisse, GCC Patches
On Fri, 19 Jun 2015, Marek Polacek wrote:
> On Thu, Jun 18, 2015 at 05:41:18PM +0200, Marek Polacek wrote:
> > > Again for symmetry, it seems like this comes with
> > > x + y - (x | y) -> x & y
> > > x + y - (x & y) -> x | y
> > > which seem fine when overflow is undefined or wraps, but not if for instance
> > > it saturates.
> >
> > I'll leave this as a follow-up.
>
> ...here.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2015-06-19 Marek Polacek <polacek@redhat.com>
>
> * match.pd (x + y - (x | y) -> x & y,
) missing
> (x + y) - (x & y) -> x | y): New patterns.
>
> * gcc.dg/fold-minus-4.c: New test.
> * gcc.dg/fold-minus-5.c: New test.
>
> diff --git gcc/match.pd gcc/match.pd
> index badb80a..61ff710 100644
> --- gcc/match.pd
> +++ gcc/match.pd
> @@ -343,6 +343,18 @@ along with GCC; see the file COPYING3. If not see
> (plus:c (bit_and @0 @1) (bit_ior @0 @1))
> (plus @0 @1))
>
> +/* x + y - (x | y) -> x & y */
Please wrap x + y in () here as well.
Ok with that changes.
Thanks,
Richard.
> +(simplify
> + (minus (plus @0 @1) (bit_ior @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> + (bit_and @0 @1)))
> +
> +/* (x + y) - (x & y) -> x | y */
> +(simplify
> + (minus (plus @0 @1) (bit_and @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> + (bit_ior @0 @1)))
> +
> /* (x | y) - (x ^ y) -> x & y */
> (simplify
> (minus (bit_ior @0 @1) (bit_xor @0 @1))
> diff --git gcc/testsuite/gcc.dg/fold-minus-4.c gcc/testsuite/gcc.dg/fold-minus-4.c
> index e69de29..2d76b4f 100644
> --- gcc/testsuite/gcc.dg/fold-minus-4.c
> +++ gcc/testsuite/gcc.dg/fold-minus-4.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-minus-5.c gcc/testsuite/gcc.dg/fold-minus-5.c
> index e69de29..a31e1cc 100644
> --- gcc/testsuite/gcc.dg/fold-minus-5.c
> +++ gcc/testsuite/gcc.dg/fold-minus-5.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = a | b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = a | b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = b | a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = b | a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
>
> Marek
>
>
--
Richard Biener <rguenther@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham Norton, HRB 21284 (AG Nuernberg)
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-19 16:22 ` Marc Glisse
@ 2015-06-22 19:10 ` Marek Polacek
2015-06-23 8:15 ` Richard Biener
0 siblings, 1 reply; 14+ messages in thread
From: Marek Polacek @ 2015-06-22 19:10 UTC (permalink / raw)
To: Marc Glisse; +Cc: GCC Patches, Richard Biener
On Fri, Jun 19, 2015 at 05:51:53PM +0200, Marc Glisse wrote:
> On Fri, 19 Jun 2015, Marek Polacek wrote:
>
> >+/* x + y - (x | y) -> x & y */
> >+(simplify
> >+ (minus (plus @0 @1) (bit_ior @0 @1))
> >+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> >+ (bit_and @0 @1)))
> >+
> >+/* (x + y) - (x & y) -> x | y */
> >+(simplify
> >+ (minus (plus @0 @1) (bit_and @0 @1))
> >+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> >+ (bit_ior @0 @1)))
>
> It could be macroized so they are handled by the same piece of code, but
> that's not important for a couple lines.
Yeah, that could be done, but I didn't see much value in doing that.
> As far as I can tell, TYPE_SATURATING is for fixed point numbers only, are
> we allowed to use bit_ior/bit_and on those? I never know what kind of
> integers are supposed to be supported, so I would have checked
> TYPE_OVERFLOW_UNDEFINED (type) || TYPE_OVERFLOW_WRAPS (type) since those are
> the 2 cases where we know it is safe (for TYPE_OVERFLOW_TRAPS it is never
> clear if we are supposed to preserve traps or just avoid introducing new
> ones). Well, the reviewer will know, I'll shut up :-)
I think you're right about TYPE_SATURATING so I've dropped that and instead
replaced it with TYPE_OVERFLOW_TRAPS. That should do the right thing
together with TYPE_OVERFLOW_SANITIZED.
> (I still believe that the necessity for TYPE_OVERFLOW_SANITIZED here points
> to a design issue in ubsan, but it is way too late to discuss that)
I think delayed folding would help here a bit. Also, we've been talking
about doing the signed overflow sanitization earlier, but so far I didn't
implement that. And -ftrapv should be merged into the ubsan infrastructure
some day.
> It is probably not worth the trouble adding the variant:
> x+(y-(x&y)) -> x|y
> since it decomposes as
> y-(x&y) -> y&~x
> x+(y&~x) -> x|y
> x+(y-(x|y)) -> x-(x&~y) -> x&y is less likely to happen because the first
> transform y-(x|y) -> -(x&~y) increases the number of insns. Bah, we can't
> handle everything...
That sounds about right ;). Thanks!
So, Richi, is this variant ok as well? I also added one ubsan test.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2015-06-22 Marek Polacek <polacek@redhat.com>
* match.pd ((x + y) - (x | y) -> x & y,
(x + y) - (x & y) -> x | y): New patterns.
* gcc.dg/fold-minus-4.c: New test.
* gcc.dg/fold-minus-5.c: New test.
* c-c++-common/ubsan/overflow-add-5.c: New test.
diff --git gcc/match.pd gcc/match.pd
index badb80a..6d520ef 100644
--- gcc/match.pd
+++ gcc/match.pd
@@ -343,6 +343,18 @@ along with GCC; see the file COPYING3. If not see
(plus:c (bit_and @0 @1) (bit_ior @0 @1))
(plus @0 @1))
+/* (x + y) - (x | y) -> x & y */
+(simplify
+ (minus (plus @0 @1) (bit_ior @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type))
+ (bit_and @0 @1)))
+
+/* (x + y) - (x & y) -> x | y */
+(simplify
+ (minus (plus @0 @1) (bit_and @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type))
+ (bit_ior @0 @1)))
+
/* (x | y) - (x ^ y) -> x & y */
(simplify
(minus (bit_ior @0 @1) (bit_xor @0 @1))
diff --git gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
index e69de29..905a60a 100644
--- gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
+++ gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow" } */
+
+int __attribute__ ((noinline))
+foo (int i, int j)
+{
+ return (i + j) - (i | j);
+}
+
+/* { dg-output "signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 2147483647 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+
+int __attribute__ ((noinline))
+bar (int i, int j)
+{
+ return (i + j) - (i & j);
+}
+
+/* { dg-output "\[^\n\r]*signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 1 cannot be represented in type 'int'" } */
+
+int
+main ()
+{
+ int r = foo (__INT_MAX__, 1);
+ asm volatile ("" : "+g" (r));
+ r = bar (__INT_MAX__, 1);
+ asm volatile ("" : "+g" (r));
+ return 0;
+}
diff --git gcc/testsuite/gcc.dg/fold-minus-4.c gcc/testsuite/gcc.dg/fold-minus-4.c
index e69de29..2d76b4f 100644
--- gcc/testsuite/gcc.dg/fold-minus-4.c
+++ gcc/testsuite/gcc.dg/fold-minus-4.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-minus-5.c gcc/testsuite/gcc.dg/fold-minus-5.c
index e69de29..a31e1cc 100644
--- gcc/testsuite/gcc.dg/fold-minus-5.c
+++ gcc/testsuite/gcc.dg/fold-minus-5.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-22 19:10 ` Marek Polacek
@ 2015-06-23 8:15 ` Richard Biener
2015-06-23 8:26 ` Marek Polacek
0 siblings, 1 reply; 14+ messages in thread
From: Richard Biener @ 2015-06-23 8:15 UTC (permalink / raw)
To: Marek Polacek; +Cc: Marc Glisse, GCC Patches
On Mon, 22 Jun 2015, Marek Polacek wrote:
> On Fri, Jun 19, 2015 at 05:51:53PM +0200, Marc Glisse wrote:
> > On Fri, 19 Jun 2015, Marek Polacek wrote:
> >
> > >+/* x + y - (x | y) -> x & y */
> > >+(simplify
> > >+ (minus (plus @0 @1) (bit_ior @0 @1))
> > >+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> > >+ (bit_and @0 @1)))
> > >+
> > >+/* (x + y) - (x & y) -> x | y */
> > >+(simplify
> > >+ (minus (plus @0 @1) (bit_and @0 @1))
> > >+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_SATURATING (type))
> > >+ (bit_ior @0 @1)))
> >
> > It could be macroized so they are handled by the same piece of code, but
> > that's not important for a couple lines.
>
> Yeah, that could be done, but I didn't see much value in doing that.
>
> > As far as I can tell, TYPE_SATURATING is for fixed point numbers only, are
> > we allowed to use bit_ior/bit_and on those? I never know what kind of
> > integers are supposed to be supported, so I would have checked
> > TYPE_OVERFLOW_UNDEFINED (type) || TYPE_OVERFLOW_WRAPS (type) since those are
> > the 2 cases where we know it is safe (for TYPE_OVERFLOW_TRAPS it is never
> > clear if we are supposed to preserve traps or just avoid introducing new
> > ones). Well, the reviewer will know, I'll shut up :-)
>
> I think you're right about TYPE_SATURATING so I've dropped that and instead
> replaced it with TYPE_OVERFLOW_TRAPS. That should do the right thing
> together with TYPE_OVERFLOW_SANITIZED.
Are you sure? The point is that if the minus or the plus in the original
expression saturate the result isn't correct, no?
> > (I still believe that the necessity for TYPE_OVERFLOW_SANITIZED here points
> > to a design issue in ubsan, but it is way too late to discuss that)
>
> I think delayed folding would help here a bit. Also, we've been talking
> about doing the signed overflow sanitization earlier, but so far I didn't
> implement that. And -ftrapv should be merged into the ubsan infrastructure
> some day.
>
> > It is probably not worth the trouble adding the variant:
> > x+(y-(x&y)) -> x|y
> > since it decomposes as
> > y-(x&y) -> y&~x
> > x+(y&~x) -> x|y
> > x+(y-(x|y)) -> x-(x&~y) -> x&y is less likely to happen because the first
> > transform y-(x|y) -> -(x&~y) increases the number of insns. Bah, we can't
> > handle everything...
>
> That sounds about right ;). Thanks!
>
> So, Richi, is this variant ok as well? I also added one ubsan test.
As said, removing TYPE_SATURATING doesn't sound correct. I'm not sure
about TYPE_OVERFLOW_TRAPS - we're certainly removing traps elsewhere
(look for the scarce use of this flag in fold-const.c and match.pd
where I only preserved those that were originally in fold-const.c).
So, TYPE_OVERFLOW_TRAPS is your choice but TYPE_SATURATING is
required IMHO.
Richard.
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2015-06-22 Marek Polacek <polacek@redhat.com>
>
> * match.pd ((x + y) - (x | y) -> x & y,
> (x + y) - (x & y) -> x | y): New patterns.
>
> * gcc.dg/fold-minus-4.c: New test.
> * gcc.dg/fold-minus-5.c: New test.
> * c-c++-common/ubsan/overflow-add-5.c: New test.
>
> diff --git gcc/match.pd gcc/match.pd
> index badb80a..6d520ef 100644
> --- gcc/match.pd
> +++ gcc/match.pd
> @@ -343,6 +343,18 @@ along with GCC; see the file COPYING3. If not see
> (plus:c (bit_and @0 @1) (bit_ior @0 @1))
> (plus @0 @1))
>
> +/* (x + y) - (x | y) -> x & y */
> +(simplify
> + (minus (plus @0 @1) (bit_ior @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type))
> + (bit_and @0 @1)))
> +
> +/* (x + y) - (x & y) -> x | y */
> +(simplify
> + (minus (plus @0 @1) (bit_and @0 @1))
> + (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type))
> + (bit_ior @0 @1)))
> +
> /* (x | y) - (x ^ y) -> x & y */
> (simplify
> (minus (bit_ior @0 @1) (bit_xor @0 @1))
> diff --git gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
> index e69de29..905a60a 100644
> --- gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
> +++ gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
> @@ -0,0 +1,30 @@
> +/* { dg-do run } */
> +/* { dg-options "-fsanitize=signed-integer-overflow" } */
> +
> +int __attribute__ ((noinline))
> +foo (int i, int j)
> +{
> + return (i + j) - (i | j);
> +}
> +
> +/* { dg-output "signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
> +/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 2147483647 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
> +
> +int __attribute__ ((noinline))
> +bar (int i, int j)
> +{
> + return (i + j) - (i & j);
> +}
> +
> +/* { dg-output "\[^\n\r]*signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
> +/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 1 cannot be represented in type 'int'" } */
> +
> +int
> +main ()
> +{
> + int r = foo (__INT_MAX__, 1);
> + asm volatile ("" : "+g" (r));
> + r = bar (__INT_MAX__, 1);
> + asm volatile ("" : "+g" (r));
> + return 0;
> +}
> diff --git gcc/testsuite/gcc.dg/fold-minus-4.c gcc/testsuite/gcc.dg/fold-minus-4.c
> index e69de29..2d76b4f 100644
> --- gcc/testsuite/gcc.dg/fold-minus-4.c
> +++ gcc/testsuite/gcc.dg/fold-minus-4.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = a & b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = b & a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
> diff --git gcc/testsuite/gcc.dg/fold-minus-5.c gcc/testsuite/gcc.dg/fold-minus-5.c
> index e69de29..a31e1cc 100644
> --- gcc/testsuite/gcc.dg/fold-minus-5.c
> +++ gcc/testsuite/gcc.dg/fold-minus-5.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fdump-tree-cddce1" } */
> +
> +int
> +fn1 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = a | b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn2 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = a | b;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn3 (int a, int b)
> +{
> + int tem1 = a + b;
> + int tem2 = b | a;
> + return tem1 - tem2;
> +}
> +
> +int
> +fn4 (int a, int b)
> +{
> + int tem1 = b + a;
> + int tem2 = b | a;
> + return tem1 - tem2;
> +}
> +
> +/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
> +/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
>
> Marek
>
>
--
Richard Biener <rguenther@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham Norton, HRB 21284 (AG Nuernberg)
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-23 8:15 ` Richard Biener
@ 2015-06-23 8:26 ` Marek Polacek
2015-06-23 8:40 ` Richard Biener
0 siblings, 1 reply; 14+ messages in thread
From: Marek Polacek @ 2015-06-23 8:26 UTC (permalink / raw)
To: Richard Biener; +Cc: Marc Glisse, GCC Patches
On Tue, Jun 23, 2015 at 09:56:33AM +0200, Richard Biener wrote:
> > I think you're right about TYPE_SATURATING so I've dropped that and instead
> > replaced it with TYPE_OVERFLOW_TRAPS. That should do the right thing
> > together with TYPE_OVERFLOW_SANITIZED.
>
> Are you sure? The point is that if the minus or the plus in the original
> expression saturate the result isn't correct, no?
Yes, but I thought that TYPE_SATURATING is only true for fixed-point, i.e.
those _Accum/_Sat/_Fract (?), and you can't do bitwise & or | on them, which
means that the TYPE_SATURATING check wouldn't be necessary.
> As said, removing TYPE_SATURATING doesn't sound correct. I'm not sure
> about TYPE_OVERFLOW_TRAPS - we're certainly removing traps elsewhere
> (look for the scarce use of this flag in fold-const.c and match.pd
> where I only preserved those that were originally in fold-const.c).
>
> So, TYPE_OVERFLOW_TRAPS is your choice but TYPE_SATURATING is
> required IMHO.
Ok, I guess I'll add TYPE_SATURATING back, even though I'm not clear
on that one, and commit.
Thanks,
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-23 8:26 ` Marek Polacek
@ 2015-06-23 8:40 ` Richard Biener
2015-06-23 10:18 ` Marek Polacek
0 siblings, 1 reply; 14+ messages in thread
From: Richard Biener @ 2015-06-23 8:40 UTC (permalink / raw)
To: Marek Polacek; +Cc: Marc Glisse, GCC Patches
On Tue, 23 Jun 2015, Marek Polacek wrote:
> On Tue, Jun 23, 2015 at 09:56:33AM +0200, Richard Biener wrote:
> > > I think you're right about TYPE_SATURATING so I've dropped that and instead
> > > replaced it with TYPE_OVERFLOW_TRAPS. That should do the right thing
> > > together with TYPE_OVERFLOW_SANITIZED.
> >
> > Are you sure? The point is that if the minus or the plus in the original
> > expression saturate the result isn't correct, no?
>
> Yes, but I thought that TYPE_SATURATING is only true for fixed-point, i.e.
> those _Accum/_Sat/_Fract (?), and you can't do bitwise & or | on them, which
> means that the TYPE_SATURATING check wouldn't be necessary.
Who says you can't do bitwise ops on them? I can't see that being
enforced in the GIMPLE checking in tree-cfg.c. Yes, there is no
such thing as a "saturating" bitwise and but bitwise and should
just work fine.
You can check with a arm cross what the C FE does when you use
bitwise ops but I believe the regular and/ior md patterns work
just fine (there are no special modes/registers but they seem
to be shared with regular registers, just special operations
are available).
Richard.
>
> > As said, removing TYPE_SATURATING doesn't sound correct. I'm not sure
> > about TYPE_OVERFLOW_TRAPS - we're certainly removing traps elsewhere
> > (look for the scarce use of this flag in fold-const.c and match.pd
> > where I only preserved those that were originally in fold-const.c).
> >
> > So, TYPE_OVERFLOW_TRAPS is your choice but TYPE_SATURATING is
> > required IMHO.
>
> Ok, I guess I'll add TYPE_SATURATING back, even though I'm not clear
> on that one, and commit.
>
> Thanks,
>
> Marek
>
>
--
Richard Biener <rguenther@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham Norton, HRB 21284 (AG Nuernberg)
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: match.pd: Three new patterns
2015-06-23 8:40 ` Richard Biener
@ 2015-06-23 10:18 ` Marek Polacek
0 siblings, 0 replies; 14+ messages in thread
From: Marek Polacek @ 2015-06-23 10:18 UTC (permalink / raw)
To: Richard Biener; +Cc: Marc Glisse, GCC Patches
On Tue, Jun 23, 2015 at 10:22:35AM +0200, Richard Biener wrote:
> Who says you can't do bitwise ops on them? I can't see that being
> enforced in the GIMPLE checking in tree-cfg.c. Yes, there is no
> such thing as a "saturating" bitwise and but bitwise and should
> just work fine.
>
> You can check with a arm cross what the C FE does when you use
> bitwise ops but I believe the regular and/ior md patterns work
> just fine (there are no special modes/registers but they seem
> to be shared with regular registers, just special operations
> are available).
Ok ;). Applied the following then.
2015-06-23 Marek Polacek <polacek@redhat.com>
* match.pd ((x + y) - (x | y) -> x & y,
(x + y) - (x & y) -> x | y): New patterns.
* gcc.dg/fold-minus-4.c: New test.
* gcc.dg/fold-minus-5.c: New test.
* c-c++-common/ubsan/overflow-add-5.c: New test.
diff --git gcc/match.pd gcc/match.pd
index badb80a..9c88e3e 100644
--- gcc/match.pd
+++ gcc/match.pd
@@ -343,6 +343,20 @@ along with GCC; see the file COPYING3. If not see
(plus:c (bit_and @0 @1) (bit_ior @0 @1))
(plus @0 @1))
+/* (x + y) - (x | y) -> x & y */
+(simplify
+ (minus (plus @0 @1) (bit_ior @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
+ && !TYPE_SATURATING (type))
+ (bit_and @0 @1)))
+
+/* (x + y) - (x & y) -> x | y */
+(simplify
+ (minus (plus @0 @1) (bit_and @0 @1))
+ (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
+ && !TYPE_SATURATING (type))
+ (bit_ior @0 @1)))
+
/* (x | y) - (x ^ y) -> x & y */
(simplify
(minus (bit_ior @0 @1) (bit_xor @0 @1))
diff --git gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
index e69de29..905a60a 100644
--- gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
+++ gcc/testsuite/c-c++-common/ubsan/overflow-add-5.c
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow" } */
+
+int __attribute__ ((noinline))
+foo (int i, int j)
+{
+ return (i + j) - (i | j);
+}
+
+/* { dg-output "signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 2147483647 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+
+int __attribute__ ((noinline))
+bar (int i, int j)
+{
+ return (i + j) - (i & j);
+}
+
+/* { dg-output "\[^\n\r]*signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 - 1 cannot be represented in type 'int'" } */
+
+int
+main ()
+{
+ int r = foo (__INT_MAX__, 1);
+ asm volatile ("" : "+g" (r));
+ r = bar (__INT_MAX__, 1);
+ asm volatile ("" : "+g" (r));
+ return 0;
+}
diff --git gcc/testsuite/gcc.dg/fold-minus-4.c gcc/testsuite/gcc.dg/fold-minus-4.c
index e69de29..2d76b4f 100644
--- gcc/testsuite/gcc.dg/fold-minus-4.c
+++ gcc/testsuite/gcc.dg/fold-minus-4.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a & b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b & a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " & " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
diff --git gcc/testsuite/gcc.dg/fold-minus-5.c gcc/testsuite/gcc.dg/fold-minus-5.c
index e69de29..a31e1cc 100644
--- gcc/testsuite/gcc.dg/fold-minus-5.c
+++ gcc/testsuite/gcc.dg/fold-minus-5.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-cddce1" } */
+
+int
+fn1 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn2 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = a | b;
+ return tem1 - tem2;
+}
+
+int
+fn3 (int a, int b)
+{
+ int tem1 = a + b;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+int
+fn4 (int a, int b)
+{
+ int tem1 = b + a;
+ int tem2 = b | a;
+ return tem1 - tem2;
+}
+
+/* { dg-final { scan-tree-dump-not " \\+ " "cddce1" } } */
+/* { dg-final { scan-tree-dump-not " \\| " "cddce1" } } */
Marek
^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2015-06-23 10:10 UTC | newest]
Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-06-12 12:25 match.pd: Three new patterns Marek Polacek
2015-06-13 10:25 ` Marc Glisse
2015-06-16 13:37 ` Richard Biener
2015-06-18 16:57 ` match.pd: Three new patterns (and some more) Marek Polacek
2015-06-22 14:40 ` Richard Biener
2015-06-18 15:42 ` match.pd: Three new patterns Marek Polacek
2015-06-19 15:34 ` Marek Polacek
2015-06-19 16:22 ` Marc Glisse
2015-06-22 19:10 ` Marek Polacek
2015-06-23 8:15 ` Richard Biener
2015-06-23 8:26 ` Marek Polacek
2015-06-23 8:40 ` Richard Biener
2015-06-23 10:18 ` Marek Polacek
2015-06-22 14:54 ` Richard Biener
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