procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Initialize value in bit_value_unop.

Browse source 
bit_value_binop initializes VAL regardless of the final mask.  It even
has a comment to that effect:

  /* Ensure that VAL is initialized (to any value).  */

However, bit_value_unop, which in theory shares the same API, does not.
This causes range-ops to choke on uninitialized VALs for some inputs to
ABS.

Instead of fixing the callers, it's cleaner to make bit_value_unop and
bit_value_binop consistent.

gcc/ChangeLog:

	* tree-ssa-ccp.cc (bit_value_unop): Initialize val when appropriate.
This commit is contained in:
Aldy Hernandez 2023-07-25 12:25:30 -04:00
parent ad0dde0af1
commit 7a48d8d28c
1 changed files with 5 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
gcc/tree-ssa-ccp.cc
View file

@ -1359,7 +1359,10 @@ bit_value_unop (enum tree_code code, signop type_sgn, int type_precision,
case ABS_EXPR:
case ABSU_EXPR:
if (wi::sext (rmask, rtype_precision) == -1)
*mask = -1;
{
*mask = -1;
*val = 0;
}
else if (wi::neg_p (rmask))
{
/* Result is either rval or -rval. */
@ -1385,6 +1388,7 @@ bit_value_unop (enum tree_code code, signop type_sgn, int type_precision,
default:
*mask = -1;
*val = 0;
break;
}
}