https://gcc.gnu.org/g:75097ad09e8169912d8640f49ac0379e8a713215
commit r16-3142-g75097ad09e8169912d8640f49ac0379e8a713215
Author: Richard Henderson <richard.hender...@linaro.org>
Date: Thu Aug 7 09:37:36 2025 +0000
aarch64: Fix gcs save/restore_stack_nonlocal
The save/restore_stack_nonlocal patterns passed a DImode rtx to
gen_tbranch_neqi3 for a QImode compare. But since we're seeding
r16 with 1, GCSEnabled will clear the only set bit in r16, so we
can use CBNZ instead of TBNZ.
gcc:
* config/aarch64/aarch64.md (tbranch_<EQL><SHORT>3): Remove.
(save_stack_nonlocal): Use aarch64_gen_compare_zero_and_branch.
(restore_stack_nonlocal): Likewise.
gcc/testsuite:
* gcc.target/aarch64/gcs-nonlocal-3.c: Match cbnz.
Diff:
---
gcc/config/aarch64/aarch64.md | 14 +++++++-------
gcc/testsuite/gcc.target/aarch64/gcs-nonlocal-3.c | 2 +-
2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 3da5bc2122df..7fbd07ebfc3a 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -1413,16 +1413,16 @@
/* Save GCS with code like
mov x16, 1
chkfeat x16
- tbnz x16, 0, .L_done
+ cbnz x16, .L_done
mrs tmp, gcspr_el0
str tmp, [%0, 8]
.L_done: */
- rtx done_label = gen_label_rtx ();
+ auto done_label = gen_label_rtx ();
rtx r16 = gen_rtx_REG (DImode, R16_REGNUM);
emit_move_insn (r16, const1_rtx);
emit_insn (gen_aarch64_chkfeat ());
- emit_insn (gen_tbranch_neqi3 (r16, const0_rtx, done_label));
+ emit_jump_insn (aarch64_gen_compare_zero_and_branch (NE, r16,
done_label));
rtx gcs_slot = adjust_address (operands[0], Pmode, GET_MODE_SIZE
(Pmode));
rtx gcs = gen_reg_rtx (Pmode);
emit_insn (gen_aarch64_load_gcspr (gcs));
@@ -1445,7 +1445,7 @@
/* Restore GCS with code like
mov x16, 1
chkfeat x16
- tbnz x16, 0, .L_done
+ cbnz x16, .L_done
ldr tmp1, [%1, 8]
mrs tmp2, gcspr_el0
subs tmp2, tmp1, tmp2
@@ -1456,12 +1456,12 @@
b.ne .L_loop
.L_done: */
- rtx loop_label = gen_label_rtx ();
- rtx done_label = gen_label_rtx ();
+ auto loop_label = gen_label_rtx ();
+ auto done_label = gen_label_rtx ();
rtx r16 = gen_rtx_REG (DImode, R16_REGNUM);
emit_move_insn (r16, const1_rtx);
emit_insn (gen_aarch64_chkfeat ());
- emit_insn (gen_tbranch_neqi3 (r16, const0_rtx, done_label));
+ emit_jump_insn (aarch64_gen_compare_zero_and_branch (NE, r16,
done_label));
rtx gcs_slot = adjust_address (operands[1], Pmode, GET_MODE_SIZE
(Pmode));
rtx gcs_old = gen_reg_rtx (Pmode);
emit_move_insn (gcs_old, gcs_slot);
diff --git a/gcc/testsuite/gcc.target/aarch64/gcs-nonlocal-3.c
b/gcc/testsuite/gcc.target/aarch64/gcs-nonlocal-3.c
index e2391555150b..7a76b14e1e74 100644
--- a/gcc/testsuite/gcc.target/aarch64/gcs-nonlocal-3.c
+++ b/gcc/testsuite/gcc.target/aarch64/gcs-nonlocal-3.c
@@ -7,7 +7,7 @@ void run (void (*)());
** bar.0:
** ...
** hint 40 // chkfeat x16
-** tbnz w16, 0, (\.L[0-9]+)
+** cbnz x16, (\.L[0-9]+)
** ...
** mrs (x[0-9]+), s3_3_c2_c5_1 // gcspr_el0
** subs x[0-9]+, x[0-9]+, \2
