The testcase used to get scheduled differently depending on the
presence of debug insns with MEMs. It's not clear to me why those
MEMs affected scheduling, but the cselib pre-canonicalization of the
MEM address is not used at all when analyzing debug insns, so the
memory allocation and lookup are pure waste. Somehow, avoiding that
waste fixes the problem, or makes it go latent.
Regstrapped on x86_64-linux-gnu. Ok to install?
for gcc/ChangeLog
PR debug/106746
* sched-deps.cc (sched_analyze_2): Skip cselib address lookup
within debug insns.
for gcc/testsuite/ChangeLog
PR debug/106746
* gcc.dg/target/i386/pr106746.c: New.
---
gcc/sched-deps.cc | 36 +++++++++++++++---------------
gcc/testsuite/gcc.target/i386/pr106746.c | 29 ++++++++++++++++++++++++
2 files changed, 47 insertions(+), 18 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/pr106746.c
diff --git a/gcc/sched-deps.cc b/gcc/sched-deps.cc
index f9371b81fb41e..a9214f674329a 100644
--- a/gcc/sched-deps.cc
+++ b/gcc/sched-deps.cc
@@ -2605,26 +2605,26 @@ sched_analyze_2 (class deps_desc *deps, rtx x, rtx_insn
*insn)
case MEM:
{
- /* Reading memory. */
- rtx_insn_list *u;
- rtx_insn_list *pending;
- rtx_expr_list *pending_mem;
- rtx t = x;
-
- if (sched_deps_info->use_cselib)
- {
- machine_mode address_mode = get_address_mode (t);
-
- t = shallow_copy_rtx (t);
- cselib_lookup_from_insn (XEXP (t, 0), address_mode, 1,
- GET_MODE (t), insn);
- XEXP (t, 0)
- = cselib_subst_to_values_from_insn (XEXP (t, 0), GET_MODE (t),
- insn);
- }
-
if (!DEBUG_INSN_P (insn))
{
+ /* Reading memory. */
+ rtx_insn_list *u;
+ rtx_insn_list *pending;
+ rtx_expr_list *pending_mem;
+ rtx t = x;
+
+ if (sched_deps_info->use_cselib)
+ {
+ machine_mode address_mode = get_address_mode (t);
+
+ t = shallow_copy_rtx (t);
+ cselib_lookup_from_insn (XEXP (t, 0), address_mode, 1,
+ GET_MODE (t), insn);
+ XEXP (t, 0)
+ = cselib_subst_to_values_from_insn (XEXP (t, 0), GET_MODE (t),
+ insn);
+ }
+
t = canon_rtx (t);
pending = deps->pending_read_insns;
pending_mem = deps->pending_read_mems;
diff --git a/gcc/testsuite/gcc.target/i386/pr106746.c
b/gcc/testsuite/gcc.target/i386/pr106746.c
new file mode 100644
index 0000000000000..14f7dab71d691
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr106746.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fsched2-use-superblocks -fcompare-debug -Wno-psabi" } */
+
+typedef char __attribute__((__vector_size__ (64))) U;
+typedef short __attribute__((__vector_size__ (64))) V;
+typedef int __attribute__((__vector_size__ (64))) W;
+
+char c;
+U a;
+U *r;
+W foo0_v512u32_0;
+
+void
+foo (W)
+{
+ U u;
+ V v;
+ W w = __builtin_shuffle (foo0_v512u32_0, foo0_v512u32_0);
+ u =
+ __builtin_shufflevector (a, u, 3, 0, 4, 9, 9, 6, 7, 8, 5,
+ 0, 6, 1, 8, 1, 2, 8, 6,
+ 1, 8, 4, 9, 3, 8, 4, 6, 0, 9, 0, 1, 8, 2, 3, 3,
+ 0, 4, 9, 9, 6, 7, 8, 5,
+ 0, 6, 1, 8, 1, 2, 8, 6,
+ 1, 8, 4, 9, 3, 8, 4, 6, 0, 9, 0, 1, 8, 2, 3);
+ v *= c;
+ w &= c;
+ *r = (U) v + (U) w;
+}
--
Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/
Free Software Activist GNU Toolchain Engineer
Disinformation flourishes because many people care deeply about injustice
but very few check the facts. Ask me about <https://stallmansupport.org>
