https://gcc.gnu.org/g:9e9c8aaab10ffeeb58c4936b55e8126ad5e31307
commit r16-1408-g9e9c8aaab10ffeeb58c4936b55e8126ad5e31307
Author: Jakub Jelinek <ja...@redhat.com>
Date: Wed Jun 11 07:00:27 2025 +0200
internal-fn: Fix up .POPCOUNT expansion
Apparently my ranger during expansion patch broke bootstrap on
aarch64-linux, while building libsupc++, there is endless recursion
on __builtin_popcountl (x) == 1 expansion.
The hack to temporarily replace SSA_NAME_VAR of the lhs which replaced
the earlier hack to temporarily change the gimple_call_lhs relies on
the lhs being expanded with EXPAND_WRITE when expanding that ifn call.
Unfortunately, in two spots I was using expand_normal (lhs) instead
of expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE) which was used
everywhere else in internal-fn.cc. This happened to work fine in the
past, but doesn't anymore. git blame shows it was my patch using
these incorrect calls.
2025-06-11 Jakub Jelinek <ja...@redhat.com>
* internal-fn.cc (expand_POPCOUNT): Use
expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE) instead of
expand_normal (lhs).
Diff:
---
gcc/internal-fn.cc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc
index a0a73fefb906..3f4ac937367d 100644
--- a/gcc/internal-fn.cc
+++ b/gcc/internal-fn.cc
@@ -5561,7 +5561,7 @@ expand_POPCOUNT (internal_fn fn, gcall *stmt)
expand_unary_optab_fn (fn, stmt, popcount_optab);
rtx_insn *popcount_insns = end_sequence ();
start_sequence ();
- rtx plhs = expand_normal (lhs);
+ rtx plhs = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
rtx pcmp = emit_store_flag (NULL_RTX, EQ, plhs, const1_rtx, lhsmode, 0, 0);
if (pcmp == NULL_RTX)
{
@@ -5603,7 +5603,7 @@ expand_POPCOUNT (internal_fn fn, gcall *stmt)
{
start_sequence ();
emit_insn (cmp_insns);
- plhs = expand_normal (lhs);
+ plhs = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
if (GET_MODE (cmp) != GET_MODE (plhs))
cmp = convert_to_mode (GET_MODE (plhs), cmp, 1);
/* For `<= 1`, we need to produce `2 - cmp` or `cmp ? 1 : 2` as that
