https://gcc.gnu.org/g:0451bc503da9c858e9f1ddfb8faec367c2e032c8
commit r15-2896-g0451bc503da9c858e9f1ddfb8faec367c2e032c8
Author: Peter Bergner <berg...@linux.ibm.com>
Date: Tue Jun 18 17:42:45 2024 -0500
rs6000: ROP - Do not disable shrink-wrapping for leaf functions [PR114759]
Only disable shrink-wrapping when using -mrop-protect when we know we
will be emitting the ROP-protect hash instructions (ie, non-leaf functions).
2024-06-17 Peter Bergner <berg...@linux.ibm.com>
gcc/
PR target/114759
* config/rs6000/rs6000.cc (rs6000_override_options_after_change):
Move
the disabling of shrink-wrapping from here....
* config/rs6000/rs6000-logue.cc (rs6000_emit_prologue): ...to here.
gcc/testsuite/
PR target/114759
* gcc.target/powerpc/pr114759-1.c: New test.
Diff:
---
gcc/config/rs6000/rs6000-logue.cc | 5 +++++
gcc/config/rs6000/rs6000.cc | 4 ----
gcc/testsuite/gcc.target/powerpc/pr114759-1.c | 16 ++++++++++++++++
3 files changed, 21 insertions(+), 4 deletions(-)
diff --git a/gcc/config/rs6000/rs6000-logue.cc
b/gcc/config/rs6000/rs6000-logue.cc
index edc0d6c8f520..fdb6414f486f 100644
--- a/gcc/config/rs6000/rs6000-logue.cc
+++ b/gcc/config/rs6000/rs6000-logue.cc
@@ -3012,6 +3012,11 @@ rs6000_emit_prologue (void)
&& (lookup_attribute ("no_split_stack",
DECL_ATTRIBUTES (cfun->decl))
== NULL));
+ /* If we are inserting ROP-protect hash instructions, disable shrink-wrap
+ until the bug where the hashst insn is emitted in the wrong location
+ is fixed. See PR101324 for details. */
+ if (info->rop_hash_size)
+ flag_shrink_wrap = 0;
frame_pointer_needed_indeed
= frame_pointer_needed && df_regs_ever_live_p (HARD_FRAME_POINTER_REGNUM);
diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index 0bcc6a2d0ab6..f2bd9edea8a1 100644
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -3431,10 +3431,6 @@ rs6000_override_options_after_change (void)
else if (!OPTION_SET_P (flag_cunroll_grow_size))
flag_cunroll_grow_size = flag_peel_loops || optimize >= 3;
- /* If we are inserting ROP-protect instructions, disable shrink wrap. */
- if (rs6000_rop_protect)
- flag_shrink_wrap = 0;
-
/* One of the late-combine passes runs after register allocation
and can match define_insn_and_splits that were previously used
only before register allocation. Some of those define_insn_and_splits
diff --git a/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
b/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
new file mode 100644
index 000000000000..579e08e920f2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mdejagnu-cpu=power10 -mrop-protect
-fdump-rtl-pro_and_epilogue" } */
+/* { dg-require-effective-target rop_ok } Only enable on supported ABIs. */
+
+/* Verify we still attempt shrink-wrapping when using -mrop-protect
+ and there are no function calls. */
+
+long
+foo (long arg)
+{
+ if (arg)
+ asm ("" ::: "r20");
+ return 0;
+}
+
+/* { dg-final { scan-rtl-dump-times "Performing shrink-wrapping" 1
"pro_and_epilogue" } } */
