This patch fixes an ICE for a combination of:
- -fstack-clash-protection
- a frame that has SVE save slots
- a frame that has no GPR save slots
- a frame that has a VG save slot
The allocation code was folding the SVE save slot allocation into
the initial frame allocation, so that we had one allocation of
size <size of SVE registers> + 16. But the VG save code itself
expected the allocations to remain separate, since it wants to
store at a constant offset from SP or FP.
The VG save isn't shrink-wrapped and so acts as a probe of the
initial allocations. It should therefore be safe to keep separate
allocations in this case.
The scans in locally_streaming_1.c expect no stack clash protection,
so the patch forces that and adds a separate compile-only test for
when protection is enabled.
Tested on aarch64-linux-gnu & pushed.
Richard
gcc/
PR target/113995
* config/aarch64/aarch64.cc (aarch64_expand_prologue): Don't
fold the SVE allocation into the initial allocation if the
initial allocation includes a VG save.
gcc/testsuite/
PR target/113995
* gcc.target/aarch64/sme/locally_streaming_1.c: Require
-fno-stack-clash-protection.
* gcc.target/aarch64/sme/locally_streaming_1_scp.c: New test.
---
gcc/config/aarch64/aarch64.cc | 9 +++++++--
.../gcc.target/aarch64/sme/locally_streaming_1.c | 2 +-
.../gcc.target/aarch64/sme/locally_streaming_1_scp.c | 3 +++
3 files changed, 11 insertions(+), 3 deletions(-)
create mode 100644
gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1_scp.c
diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 104f7e1831e..6a39ed8eddf 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -9523,7 +9523,9 @@ aarch64_expand_prologue (void)
if (aarch64_cfun_enables_pstate_sm ())
force_isa_mode = AARCH64_FL_SM_ON;
- if (flag_stack_clash_protection && known_eq (callee_adjust, 0))
+ if (flag_stack_clash_protection
+ && known_eq (callee_adjust, 0)
+ && known_lt (frame.reg_offset[VG_REGNUM], 0))
{
/* Fold the SVE allocation into the initial allocation.
We don't do this in aarch64_layout_arg to avoid pessimizing
@@ -9651,7 +9653,10 @@ aarch64_expand_prologue (void)
if (maybe_ne (sve_callee_adjust, 0))
{
gcc_assert (!flag_stack_clash_protection
- || known_eq (initial_adjust, 0));
+ || known_eq (initial_adjust, 0)
+ /* The VG save isn't shrink-wrapped and so serves as
+ a probe of the initial allocation. */
+ || known_eq (frame.reg_offset[VG_REGNUM], bytes_below_sp));
aarch64_allocate_and_probe_stack_space (tmp1_rtx, tmp0_rtx,
sve_callee_adjust,
force_isa_mode,
diff --git a/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1.c
b/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1.c
index 4bb637f4781..cb235f5c832 100644
--- a/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1.c
+++ b/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1.c
@@ -1,4 +1,4 @@
-// { dg-options "-O -fomit-frame-pointer" }
+// { dg-options "-O -fomit-frame-pointer -fno-stack-clash-protection" }
// { dg-final { check-function-bodies "**" "" } }
void consume_za () [[arm::streaming, arm::inout("za")]];
diff --git a/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1_scp.c
b/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1_scp.c
new file mode 100644
index 00000000000..6b7f47dce7a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sme/locally_streaming_1_scp.c
@@ -0,0 +1,3 @@
+// { dg-options "-O -fomit-frame-pointer -fstack-clash-protection" }
+
+#include "locally_streaming_1.c"
--
2.25.1
