MATCH: Fix zero_one_valued_p not to match signed 1 bit integers
Checks
Commit Message
So for the attached testcase, we assumed that zero_one_valued_p would
be the value [0,1] but currently zero_one_valued_p matches also
signed 1 bit integers.
This changes that not to match that and fixes the 2 new testcases at
all optimization levels.
OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
Note the GCC 13 patch will be slightly different due to the changes
made to zero_one_valued_p.
PR tree-optimization/110165
PR tree-optimization/110166
gcc/ChangeLog:
* match.pd (zero_one_valued_p): Don't accept
signed 1-bit integers.
gcc/testsuite/ChangeLog:
* gcc.c-torture/execute/pr110165-1.c: New test.
* gcc.c-torture/execute/pr110166-1.c: New test.
---
gcc/match.pd | 13 ++++++--
.../gcc.c-torture/execute/pr110165-1.c | 28 ++++++++++++++++
.../gcc.c-torture/execute/pr110166-1.c | 33 +++++++++++++++++++
3 files changed, 71 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr110165-1.c
create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr110166-1.c
Comments
On Fri, Jun 9, 2023 at 3:48 AM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> So for the attached testcase, we assumed that zero_one_valued_p would
> be the value [0,1] but currently zero_one_valued_p matches also
> signed 1 bit integers.
> This changes that not to match that and fixes the 2 new testcases at
> all optimization levels.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
OK.
> Note the GCC 13 patch will be slightly different due to the changes
> made to zero_one_valued_p.
>
> PR tree-optimization/110165
> PR tree-optimization/110166
>
> gcc/ChangeLog:
>
> * match.pd (zero_one_valued_p): Don't accept
> signed 1-bit integers.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.c-torture/execute/pr110165-1.c: New test.
> * gcc.c-torture/execute/pr110166-1.c: New test.
> ---
> gcc/match.pd | 13 ++++++--
> .../gcc.c-torture/execute/pr110165-1.c | 28 ++++++++++++++++
> .../gcc.c-torture/execute/pr110166-1.c | 33 +++++++++++++++++++
> 3 files changed, 71 insertions(+), 3 deletions(-)
> create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr110165-1.c
> create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr110166-1.c
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index 4ad037d641a..9a6bc2e9348 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -1984,12 +1984,19 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> @0)
>
> /* zero_one_valued_p will match when a value is known to be either
> - 0 or 1 including constants 0 or 1. */
> + 0 or 1 including constants 0 or 1.
> + Signed 1-bits includes -1 so they cannot match here. */
> (match zero_one_valued_p
> @0
> - (if (INTEGRAL_TYPE_P (type) && wi::leu_p (tree_nonzero_bits (@0), 1))))
> + (if (INTEGRAL_TYPE_P (type)
> + && (TYPE_UNSIGNED (type)
> + || TYPE_PRECISION (type) > 1)
> + && wi::leu_p (tree_nonzero_bits (@0), 1))))
> (match zero_one_valued_p
> - truth_valued_p@0)
> + truth_valued_p@0
> + (if (INTEGRAL_TYPE_P (type)
> + && (TYPE_UNSIGNED (type)
> + || TYPE_PRECISION (type) > 1))))
>
> /* Transform { 0 or 1 } * { 0 or 1 } into { 0 or 1 } & { 0 or 1 }. */
> (simplify
> diff --git a/gcc/testsuite/gcc.c-torture/execute/pr110165-1.c b/gcc/testsuite/gcc.c-torture/execute/pr110165-1.c
> new file mode 100644
> index 00000000000..9521a19428e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.c-torture/execute/pr110165-1.c
> @@ -0,0 +1,28 @@
> +struct s
> +{
> + int t : 1;
> +};
> +
> +int f(struct s t, int a, int b) __attribute__((noinline));
> +int f(struct s t, int a, int b)
> +{
> + int bd = t.t;
> + if (bd) a|=b;
> + return a;
> +}
> +
> +int main(void)
> +{
> + struct s t;
> + for(int i = -1;i <= 1; i++)
> + {
> + int a = 0x10;
> + int b = 0x0f;
> + int c = a | b;
> + struct s t = {i};
> + int r = f(t, a, b);
> + int exp = (i != 0) ? a | b : a;
> + if (exp != r)
> + __builtin_abort();
> + }
> +}
> diff --git a/gcc/testsuite/gcc.c-torture/execute/pr110166-1.c b/gcc/testsuite/gcc.c-torture/execute/pr110166-1.c
> new file mode 100644
> index 00000000000..f999d47fe69
> --- /dev/null
> +++ b/gcc/testsuite/gcc.c-torture/execute/pr110166-1.c
> @@ -0,0 +1,33 @@
> +struct s
> +{
> + int t : 1;
> + int t1 : 1;
> +};
> +
> +int f(struct s t) __attribute__((noinline));
> +int f(struct s t)
> +{
> + int c = t.t;
> + int d = t.t1;
> + if (c > d)
> + t.t = d;
> + else
> + t.t = c;
> + return t.t;
> +}
> +
> +int main(void)
> +{
> + struct s t;
> + for(int i = -1;i <= 0; i++)
> + {
> + for(int j = -1;j <= 0; j++)
> + {
> + struct s t = {i, j};
> + int r = f(t);
> + int exp = i < j ? i : j;
> + if (exp != r)
> + __builtin_abort();
> + }
> + }
> +}
> --
> 2.31.1
>
On Fri, Jun 09, 2023 at 11:06:04AM +0200, Richard Biener via Gcc-patches wrote:
> On Fri, Jun 9, 2023 at 3:48 AM Andrew Pinski via Gcc-patches
> <gcc-patches@gcc.gnu.org> wrote:
> >
> > So for the attached testcase, we assumed that zero_one_valued_p would
> > be the value [0,1] but currently zero_one_valued_p matches also
> > signed 1 bit integers.
> > This changes that not to match that and fixes the 2 new testcases at
> > all optimization levels.
> >
> > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
>
> OK.
Note, this means it won't return true for zero INTEGER_CSTs with
signed 1-bit precision type. Such value is in the [0, 1] range.
Though, I guess signed 1-bit precision types are so rare and problematic
that it doesn't hurt not to optimize that.
Jakub
@@ -1984,12 +1984,19 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
@0)
/* zero_one_valued_p will match when a value is known to be either
- 0 or 1 including constants 0 or 1. */
+ 0 or 1 including constants 0 or 1.
+ Signed 1-bits includes -1 so they cannot match here. */
(match zero_one_valued_p
@0
- (if (INTEGRAL_TYPE_P (type) && wi::leu_p (tree_nonzero_bits (@0), 1))))
+ (if (INTEGRAL_TYPE_P (type)
+ && (TYPE_UNSIGNED (type)
+ || TYPE_PRECISION (type) > 1)
+ && wi::leu_p (tree_nonzero_bits (@0), 1))))
(match zero_one_valued_p
- truth_valued_p@0)
+ truth_valued_p@0
+ (if (INTEGRAL_TYPE_P (type)
+ && (TYPE_UNSIGNED (type)
+ || TYPE_PRECISION (type) > 1))))
/* Transform { 0 or 1 } * { 0 or 1 } into { 0 or 1 } & { 0 or 1 }. */
(simplify
new file mode 100644
@@ -0,0 +1,28 @@
+struct s
+{
+ int t : 1;
+};
+
+int f(struct s t, int a, int b) __attribute__((noinline));
+int f(struct s t, int a, int b)
+{
+ int bd = t.t;
+ if (bd) a|=b;
+ return a;
+}
+
+int main(void)
+{
+ struct s t;
+ for(int i = -1;i <= 1; i++)
+ {
+ int a = 0x10;
+ int b = 0x0f;
+ int c = a | b;
+ struct s t = {i};
+ int r = f(t, a, b);
+ int exp = (i != 0) ? a | b : a;
+ if (exp != r)
+ __builtin_abort();
+ }
+}
new file mode 100644
@@ -0,0 +1,33 @@
+struct s
+{
+ int t : 1;
+ int t1 : 1;
+};
+
+int f(struct s t) __attribute__((noinline));
+int f(struct s t)
+{
+ int c = t.t;
+ int d = t.t1;
+ if (c > d)
+ t.t = d;
+ else
+ t.t = c;
+ return t.t;
+}
+
+int main(void)
+{
+ struct s t;
+ for(int i = -1;i <= 0; i++)
+ {
+ for(int j = -1;j <= 0; j++)
+ {
+ struct s t = {i, j};
+ int r = f(t);
+ int exp = i < j ? i : j;
+ if (exp != r)
+ __builtin_abort();
+ }
+ }
+}