> Am 13.05.2025 um 23:24 schrieb Martin Jambor <mjam...@suse.cz>:
>
> Hi,
>
> this patch fixes (hopefully the) one remaining place where gimple SRA
> was still creating a load into a const aggregates. It occurs when
> there was a replacement for a load but that replacement is not type
> compatible - typically because it was a single field structure.
>
> I have used testcases from duplicates because the original test-case no
> longer reproduces for me.
>
> It is kind of embarrassing how long it took me to get to this given the
> issue is actually very simple. Based on my hazy recollection from
> earlier encounters with SRA and TREE_READONLY, I had expected it to be
> quite bit more convoluted.
>
> Anyway, it passes bootstrap and testing on x86_64-linux, bootstrap on
> Aarch64, testsuite is still running there. OK for master and all active
> release branches if it passes?
Ok
Richard
> Thanks,
>
> Martin
>
>
>
> gcc/ChangeLog:
>
> 2025-05-13 Martin Jambor <mjam...@suse.cz>
>
> PR tree-optimization/111873
> * tree-sra.cc (sra_modify_expr): When processing a load which has
> a type-incompatible replacement, do not store the contents of the
> replacement into the original aggregate when that aggregate is
> const.
>
> gcc/testsuite/ChangeLog:
>
> 2025-05-13 Martin Jambor <mjam...@suse.cz>
>
> * gcc.dg/ipa/pr120044-1.c: New test.
> * gcc.dg/ipa/pr120044-2.c: Likewise.
> * gcc.dg/tree-ssa/pr114864.c: Likewise.
> ---
> gcc/testsuite/gcc.dg/ipa/pr120044-1.c | 17 +++++++++++++++++
> gcc/testsuite/gcc.dg/ipa/pr120044-2.c | 17 +++++++++++++++++
> gcc/testsuite/gcc.dg/tree-ssa/pr114864.c | 15 +++++++++++++++
> gcc/tree-sra.cc | 4 +++-
> 4 files changed, 52 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/gcc.dg/ipa/pr120044-1.c
> create mode 100644 gcc/testsuite/gcc.dg/ipa/pr120044-2.c
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr114864.c
>
> diff --git a/gcc/testsuite/gcc.dg/ipa/pr120044-1.c
> b/gcc/testsuite/gcc.dg/ipa/pr120044-1.c
> new file mode 100644
> index 00000000000..f9fee3e85af
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/ipa/pr120044-1.c
> @@ -0,0 +1,17 @@
> +/* { dg-do run } */
> +/* { dg-options "-O3 -fno-early-inlining -fno-tree-fre -fno-tree-pre
> -fno-code-hoisting -fno-inline" } */
> +
> +struct a {
> + int b;
> +} const c;
> +void d(char p, struct a e) {
> + while (e.b)
> + ;
> +}
> +static unsigned short f(const struct a g) {
> + d(g.b, g);
> + return g.b;
> +}
> +int main() {
> + return f(c);
> +}
> diff --git a/gcc/testsuite/gcc.dg/ipa/pr120044-2.c
> b/gcc/testsuite/gcc.dg/ipa/pr120044-2.c
> new file mode 100644
> index 00000000000..5130791f544
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/ipa/pr120044-2.c
> @@ -0,0 +1,17 @@
> +/* { dg-do run } */
> +/* { dg-options "-O3 -fno-early-inlining -fno-tree-fre -fno-tree-pre
> -fno-code-hoisting -fno-ipa-cp" } */
> +
> +struct a {
> + int b;
> +} const c;
> +void d(char p, struct a e) {
> + while (e.b)
> + ;
> +}
> +static unsigned short f(const struct a g) {
> + d(g.b, g);
> + return g.b;
> +}
> +int main() {
> + return f(c);
> +}
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr114864.c
> b/gcc/testsuite/gcc.dg/tree-ssa/pr114864.c
> new file mode 100644
> index 00000000000..cd9b94c094f
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr114864.c
> @@ -0,0 +1,15 @@
> +/* { dg-do run } */
> +/* { dg-options "-O1 -fno-tree-dce -fno-tree-fre" } */
> +
> +struct a {
> + int b;
> +} const c;
> +void d(const struct a f) {}
> +void e(const struct a f) {
> + f.b == 0 ? 1 : f.b;
> + d(f);
> +}
> +int main() {
> + e(c);
> + return 0;
> +}
> diff --git a/gcc/tree-sra.cc b/gcc/tree-sra.cc
> index 302b73e83b8..4b6daf77284 100644
> --- a/gcc/tree-sra.cc
> +++ b/gcc/tree-sra.cc
> @@ -4205,8 +4205,10 @@ sra_modify_expr (tree *expr, bool write,
> gimple_stmt_iterator *stmt_gsi,
> }
> else
> {
> - gassign *stmt;
> + if (TREE_READONLY (access->base))
> + return false;
>
> + gassign *stmt;
> if (access->grp_partial_lhs)
> repl = force_gimple_operand_gsi (stmt_gsi, repl, true,
> NULL_TREE, true,
> --
> 2.49.0
>
