diff mbox series

Export value/mask known bits from CCP.

Message ID 20230717075645.243653-1-aldyh@redhat.com
State New
Headers show
Series Export value/mask known bits from CCP. | expand

Commit Message

Aldy Hernandez July 17, 2023, 7:56 a.m. UTC 
Currently CCP throws away the known 1 bits because VRP and irange have
traditionally only had a way of tracking known 0s (set_nonzero_bits).
With the ability to keep all the known bits in the irange, we can now
save this between passes.

OK?

gcc/ChangeLog:

	* tree-ssa-ccp.cc (ccp_finalize): Export value/mask known bits.
---
 gcc/tree-ssa-ccp.cc | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

Comments

Richard Biener July 17, 2023, 11:52 a.m. UTC | #1 
On Mon, Jul 17, 2023 at 9:57 AM Aldy Hernandez via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> Currently CCP throws away the known 1 bits because VRP and irange have
> traditionally only had a way of tracking known 0s (set_nonzero_bits).
> With the ability to keep all the known bits in the irange, we can now
> save this between passes.
>
> OK?

OK.

> gcc/ChangeLog:
>
>         * tree-ssa-ccp.cc (ccp_finalize): Export value/mask known bits.
> ---
>  gcc/tree-ssa-ccp.cc | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/gcc/tree-ssa-ccp.cc b/gcc/tree-ssa-ccp.cc
> index 0d0f02a8442..64d5fa81334 100644
> --- a/gcc/tree-ssa-ccp.cc
> +++ b/gcc/tree-ssa-ccp.cc
> @@ -1020,11 +1020,9 @@ ccp_finalize (bool nonzero_p)
>        else
>         {
>           unsigned int precision = TYPE_PRECISION (TREE_TYPE (val->value));
> -         wide_int nonzero_bits
> -           = (wide_int::from (val->mask, precision, UNSIGNED)
> -              | wi::to_wide (val->value));
> -         nonzero_bits &= get_nonzero_bits (name);
> -         set_nonzero_bits (name, nonzero_bits);
> +         wide_int value = wi::to_wide (val->value);
> +         wide_int mask = wide_int::from (val->mask, precision, UNSIGNED);
> +         set_bitmask (name, value, mask);
>         }
>      }
>
> --
> 2.40.1
>
diff mbox series

Patch

diff --git a/gcc/tree-ssa-ccp.cc b/gcc/tree-ssa-ccp.cc
index 0d0f02a8442..64d5fa81334 100644
--- a/gcc/tree-ssa-ccp.cc
+++ b/gcc/tree-ssa-ccp.cc
@@ -1020,11 +1020,9 @@  ccp_finalize (bool nonzero_p)
       else
 	{
 	  unsigned int precision = TYPE_PRECISION (TREE_TYPE (val->value));
-	  wide_int nonzero_bits
-	    = (wide_int::from (val->mask, precision, UNSIGNED)
-	       | wi::to_wide (val->value));
-	  nonzero_bits &= get_nonzero_bits (name);
-	  set_nonzero_bits (name, nonzero_bits);
+	  wide_int value = wi::to_wide (val->value);
+	  wide_int mask = wide_int::from (val->mask, precision, UNSIGNED);
+	  set_bitmask (name, value, mask);
 	}
     }