[gcc r15-1013] fold-const: Handle CTZ like CLZ in tree_call_nonnegative_warnv_p [PR115337]

[Jakub Jelinek via Gcc-cvs]

https://gcc.gnu.org/g:181861b072ff1ef650c1a9d0290a4a672b9e747c

commit r15-1013-g181861b072ff1ef650c1a9d0290a4a672b9e747c
Author: Jakub Jelinek <ja...@redhat.com>
Date:   Tue Jun 4 15:52:09 2024 +0200

    fold-const: Handle CTZ like CLZ in tree_call_nonnegative_warnv_p [PR115337]
    
    I think we can handle CTZ exactly like CLZ in tree_call_nonnegative_warnv_p.
    Like CLZ, if it is UB at zero, the result range is [0, prec-1] and if it is
    well defined at zero, the second argument provides the value at zero.
    
    2024-06-04  Jakub Jelinek  <ja...@redhat.com>
    
            PR tree-optimization/115337
            * fold-const.cc (tree_call_nonnegative_warnv_p): Handle
            CASE_CFN_CTZ like CASE_CFN_CLZ.

Diff:
---
 gcc/fold-const.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 048c654c848..92b048c307e 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -15250,6 +15250,7 @@ tree_call_nonnegative_warnv_p (tree type, combined_fn 
fn, tree arg0, tree arg1,
       return true;
 
     CASE_CFN_CLZ:
+    CASE_CFN_CTZ:
       if (arg1)
        return RECURSE (arg1);
       return true;