MATCH: Add simplifications of `(a == CST) & a`

Message ID 20230916155924.1679335-1-apinski@marvell.com
State Committed
Commit 0fb828af75732d39c644fd145c29d41ca14b8cb1
Headers
Series MATCH: Add simplifications of `(a == CST) & a` |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_gcc_build--master-aarch64 success Testing passed
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Commit Message

Andrew Pinski Sept. 16, 2023, 3:59 p.m. UTC
  `(a == CST) & a` can be either simplified to simplying `a == CST`
or 0 depending on the first bit of the CST.
This is an extension of the already pattern of `X & !X` and allows
us to remove the 2 xfails on gcc.dg/binop-notand1a.c and gcc.dg/binop-notand4a.c.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

	PR tree-optimization/111431

gcc/ChangeLog:

	* match.pd (`(a == CST) & a`): New pattern.

gcc/testsuite/ChangeLog:

	* gcc.dg/binop-notand1a.c: Remove xfail.
	* gcc.dg/binop-notand4a.c: Likewise.
	* gcc.c-torture/execute/pr111431-1.c: New test.
	* gcc.dg/binop-andeq1.c: New test.
	* gcc.dg/binop-andeq2.c: New test.
	* gcc.dg/binop-notand7.c: New test.
	* gcc.dg/binop-notand7a.c: New test.
---
 gcc/match.pd                                  |  8 ++++
 .../gcc.c-torture/execute/pr111431-1.c        | 39 +++++++++++++++++++
 gcc/testsuite/gcc.dg/binop-andeq1.c           | 12 ++++++
 gcc/testsuite/gcc.dg/binop-andeq2.c           | 14 +++++++
 gcc/testsuite/gcc.dg/binop-notand1a.c         |  4 +-
 gcc/testsuite/gcc.dg/binop-notand4a.c         |  4 +-
 gcc/testsuite/gcc.dg/binop-notand7.c          | 12 ++++++
 gcc/testsuite/gcc.dg/binop-notand7a.c         | 12 ++++++
 8 files changed, 99 insertions(+), 6 deletions(-)
 create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
 create mode 100644 gcc/testsuite/gcc.dg/binop-andeq1.c
 create mode 100644 gcc/testsuite/gcc.dg/binop-andeq2.c
 create mode 100644 gcc/testsuite/gcc.dg/binop-notand7.c
 create mode 100644 gcc/testsuite/gcc.dg/binop-notand7a.c
  

Comments

Richard Biener Sept. 18, 2023, 7:37 a.m. UTC | #1
On Sat, Sep 16, 2023 at 6:00 PM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> `(a == CST) & a` can be either simplified to simplying `a == CST`
> or 0 depending on the first bit of the CST.
> This is an extension of the already pattern of `X & !X` and allows
> us to remove the 2 xfails on gcc.dg/binop-notand1a.c and gcc.dg/binop-notand4a.c.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

OK.

>         PR tree-optimization/111431
>
> gcc/ChangeLog:
>
>         * match.pd (`(a == CST) & a`): New pattern.
>
> gcc/testsuite/ChangeLog:
>
>         * gcc.dg/binop-notand1a.c: Remove xfail.
>         * gcc.dg/binop-notand4a.c: Likewise.
>         * gcc.c-torture/execute/pr111431-1.c: New test.
>         * gcc.dg/binop-andeq1.c: New test.
>         * gcc.dg/binop-andeq2.c: New test.
>         * gcc.dg/binop-notand7.c: New test.
>         * gcc.dg/binop-notand7a.c: New test.
> ---
>  gcc/match.pd                                  |  8 ++++
>  .../gcc.c-torture/execute/pr111431-1.c        | 39 +++++++++++++++++++
>  gcc/testsuite/gcc.dg/binop-andeq1.c           | 12 ++++++
>  gcc/testsuite/gcc.dg/binop-andeq2.c           | 14 +++++++
>  gcc/testsuite/gcc.dg/binop-notand1a.c         |  4 +-
>  gcc/testsuite/gcc.dg/binop-notand4a.c         |  4 +-
>  gcc/testsuite/gcc.dg/binop-notand7.c          | 12 ++++++
>  gcc/testsuite/gcc.dg/binop-notand7a.c         | 12 ++++++
>  8 files changed, 99 insertions(+), 6 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
>  create mode 100644 gcc/testsuite/gcc.dg/binop-andeq1.c
>  create mode 100644 gcc/testsuite/gcc.dg/binop-andeq2.c
>  create mode 100644 gcc/testsuite/gcc.dg/binop-notand7.c
>  create mode 100644 gcc/testsuite/gcc.dg/binop-notand7a.c
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index ebb50ee0581..65960a1701e 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -5172,6 +5172,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>   )
>  )
>
> +/* `(a == CST) & a` can be simplified to `0` or `(a == CST)` depending
> +   on the first bit of the CST.  */
> +(simplify
> + (bit_and:c (convert@2 (eq @0 INTEGER_CST@1)) (convert? @0))
> + (if ((wi::to_wide (@1) & 1) != 0)
> +  @2
> +  { build_zero_cst (type); }))
> +
>  /* Optimize
>     # x_5 in range [cst1, cst2] where cst2 = cst1 + 1
>     x_5 ? cstN ? cst4 : cst3
> diff --git a/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c b/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
> new file mode 100644
> index 00000000000..a96dbadf2b5
> --- /dev/null
> +++ b/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
> @@ -0,0 +1,39 @@
> +int
> +foo (int a)
> +{
> +  int b = a == 0;
> +  return (a & b);
> +}
> +
> +#define function(vol,cst) \
> +__attribute__((noipa)) \
> +_Bool func_##cst##_##vol(vol int a) \
> +{ \
> +  vol int b = a == cst; \
> +  return (a & b); \
> +}
> +
> +#define funcdefs(cst) \
> +function(,cst) \
> +function(volatile,cst)
> +
> +#define funcs(f) \
> +f(0) \
> +f(1) \
> +f(5)
> +
> +funcs(funcdefs)
> +
> +#define test(cst) \
> +do { \
> + if(func_##cst##_(a) != func_##cst##_volatile(a))\
> +   __builtin_abort(); \
> +} while(0);
> +int main(void)
> +{
> +  for(int a = -10; a <= 10; a++)
> +   {
> +     funcs(test)
> +   }
> +}
> +
> diff --git a/gcc/testsuite/gcc.dg/binop-andeq1.c b/gcc/testsuite/gcc.dg/binop-andeq1.c
> new file mode 100644
> index 00000000000..2a92b8f95df
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/binop-andeq1.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* PR tree-optimization/111431 */
> +
> +int
> +foo (int a)
> +{
> +  int b = a == 2;
> +  return (a & b);
> +}
> +
> +/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
> diff --git a/gcc/testsuite/gcc.dg/binop-andeq2.c b/gcc/testsuite/gcc.dg/binop-andeq2.c
> new file mode 100644
> index 00000000000..895262fc17e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/binop-andeq2.c
> @@ -0,0 +1,14 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* PR tree-optimization/111431 */
> +
> +int
> +foo (int a)
> +{
> +  int b = a == 1025;
> +  return (a & b);
> +}
> +
> +/* { dg-final { scan-tree-dump-not "return 0"  "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " & "  "optimized" } } */
> +/* { dg-final { scan-tree-dump-times " == 1025;" 1  "optimized" } } */
> diff --git a/gcc/testsuite/gcc.dg/binop-notand1a.c b/gcc/testsuite/gcc.dg/binop-notand1a.c
> index c7e932b2638..d94685eb4ce 100644
> --- a/gcc/testsuite/gcc.dg/binop-notand1a.c
> +++ b/gcc/testsuite/gcc.dg/binop-notand1a.c
> @@ -7,6 +7,4 @@ foo (char a, unsigned short b)
>    return (a & !a) | (b & !b);
>  }
>
> -/* As long as comparisons aren't boolified and casts from boolean-types
> -   aren't preserved, the folding of  X & !X to zero fails.  */
> -/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
> +/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized"  } } */
> diff --git a/gcc/testsuite/gcc.dg/binop-notand4a.c b/gcc/testsuite/gcc.dg/binop-notand4a.c
> index dce6a5c7eb5..bd9c7cce638 100644
> --- a/gcc/testsuite/gcc.dg/binop-notand4a.c
> +++ b/gcc/testsuite/gcc.dg/binop-notand4a.c
> @@ -7,6 +7,4 @@ foo (unsigned char a, _Bool b)
>    return (!a & a) | (b & !b);
>  }
>
> -/* As long as comparisons aren't boolified and casts from boolean-types
> -   aren't preserved, the folding of  X & !X to zero fails.  */
> -/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
> +/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
> diff --git a/gcc/testsuite/gcc.dg/binop-notand7.c b/gcc/testsuite/gcc.dg/binop-notand7.c
> new file mode 100644
> index 00000000000..c2bb6a0449d
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/binop-notand7.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* PR tree-optimization/111431 */
> +
> +int
> +foo (int a)
> +{
> +  int b = !a;
> +  return (a & b);
> +}
> +
> +/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
> diff --git a/gcc/testsuite/gcc.dg/binop-notand7a.c b/gcc/testsuite/gcc.dg/binop-notand7a.c
> new file mode 100644
> index 00000000000..dd50916da61
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/binop-notand7a.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* PR tree-optimization/111431 */
> +
> +unsigned
> +foo (int a)
> +{
> +  int b = !a;
> +  return (a & b);
> +}
> +
> +/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
> --
> 2.31.1
>
  

Patch

diff --git a/gcc/match.pd b/gcc/match.pd
index ebb50ee0581..65960a1701e 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -5172,6 +5172,14 @@  DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
  )
 )
 
+/* `(a == CST) & a` can be simplified to `0` or `(a == CST)` depending
+   on the first bit of the CST.  */
+(simplify
+ (bit_and:c (convert@2 (eq @0 INTEGER_CST@1)) (convert? @0))
+ (if ((wi::to_wide (@1) & 1) != 0)
+  @2
+  { build_zero_cst (type); }))
+
 /* Optimize
    # x_5 in range [cst1, cst2] where cst2 = cst1 + 1
    x_5 ? cstN ? cst4 : cst3
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c b/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
new file mode 100644
index 00000000000..a96dbadf2b5
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr111431-1.c
@@ -0,0 +1,39 @@ 
+int
+foo (int a)
+{
+  int b = a == 0;
+  return (a & b);
+}
+
+#define function(vol,cst) \
+__attribute__((noipa)) \
+_Bool func_##cst##_##vol(vol int a) \
+{ \
+  vol int b = a == cst; \
+  return (a & b); \
+}
+
+#define funcdefs(cst) \
+function(,cst) \
+function(volatile,cst)
+
+#define funcs(f) \
+f(0) \
+f(1) \
+f(5)
+
+funcs(funcdefs)
+
+#define test(cst) \
+do { \
+ if(func_##cst##_(a) != func_##cst##_volatile(a))\
+   __builtin_abort(); \
+} while(0);
+int main(void)
+{
+  for(int a = -10; a <= 10; a++)
+   {
+     funcs(test)
+   }
+}
+
diff --git a/gcc/testsuite/gcc.dg/binop-andeq1.c b/gcc/testsuite/gcc.dg/binop-andeq1.c
new file mode 100644
index 00000000000..2a92b8f95df
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-andeq1.c
@@ -0,0 +1,12 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* PR tree-optimization/111431 */
+
+int
+foo (int a)
+{
+  int b = a == 2;
+  return (a & b);
+}
+
+/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-andeq2.c b/gcc/testsuite/gcc.dg/binop-andeq2.c
new file mode 100644
index 00000000000..895262fc17e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-andeq2.c
@@ -0,0 +1,14 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* PR tree-optimization/111431 */
+
+int
+foo (int a)
+{
+  int b = a == 1025;
+  return (a & b);
+}
+
+/* { dg-final { scan-tree-dump-not "return 0"  "optimized" } } */
+/* { dg-final { scan-tree-dump-not " & "  "optimized" } } */
+/* { dg-final { scan-tree-dump-times " == 1025;" 1  "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-notand1a.c b/gcc/testsuite/gcc.dg/binop-notand1a.c
index c7e932b2638..d94685eb4ce 100644
--- a/gcc/testsuite/gcc.dg/binop-notand1a.c
+++ b/gcc/testsuite/gcc.dg/binop-notand1a.c
@@ -7,6 +7,4 @@  foo (char a, unsigned short b)
   return (a & !a) | (b & !b);
 }
 
-/* As long as comparisons aren't boolified and casts from boolean-types
-   aren't preserved, the folding of  X & !X to zero fails.  */
-/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized"  } } */
diff --git a/gcc/testsuite/gcc.dg/binop-notand4a.c b/gcc/testsuite/gcc.dg/binop-notand4a.c
index dce6a5c7eb5..bd9c7cce638 100644
--- a/gcc/testsuite/gcc.dg/binop-notand4a.c
+++ b/gcc/testsuite/gcc.dg/binop-notand4a.c
@@ -7,6 +7,4 @@  foo (unsigned char a, _Bool b)
   return (!a & a) | (b & !b);
 }
 
-/* As long as comparisons aren't boolified and casts from boolean-types
-   aren't preserved, the folding of  X & !X to zero fails.  */
-/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-notand7.c b/gcc/testsuite/gcc.dg/binop-notand7.c
new file mode 100644
index 00000000000..c2bb6a0449d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-notand7.c
@@ -0,0 +1,12 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* PR tree-optimization/111431 */
+
+int
+foo (int a)
+{
+  int b = !a;
+  return (a & b);
+}
+
+/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-notand7a.c b/gcc/testsuite/gcc.dg/binop-notand7a.c
new file mode 100644
index 00000000000..dd50916da61
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-notand7a.c
@@ -0,0 +1,12 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* PR tree-optimization/111431 */
+
+unsigned
+foo (int a)
+{
+  int b = !a;
+  return (a & b);
+}
+
+/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" } } */