From: Maciej W. Rozycki <macro@orcam.me.uk>
Date: Sun, 12 Jan 2025 16:48:53 +0000 (+0000)
Subject: Alpha: Add memory clobbers to `builtin_longjmp' expansion
X-Git-Tag: basepoints/gcc-16~2721
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=46861167f548ec622918d95acd2424b64f56797d;p=thirdparty%2Fgcc.git

Alpha: Add memory clobbers to `builtin_longjmp' expansion

Add the same memory clobbers to `builtin_longjmp' for Alpha as with
commit 41439bf6a647 ("builtins.c (expand_builtin_longjmp): Added two
memory clobbers."), to prevent instructions that access memory via the
frame or stack pointer from being moved across the write to the frame
pointer.

	gcc/
	* config/alpha/alpha.md (builtin_longjmp): Add memory clobbers.
---

diff --git a/gcc/config/alpha/alpha.md b/gcc/config/alpha/alpha.md
index 376c4cba90c5..35c8030422f5 100644
--- a/gcc/config/alpha/alpha.md
+++ b/gcc/config/alpha/alpha.md
@@ -5005,6 +5005,8 @@
   rtx pv = gen_rtx_REG (Pmode, 27);
 
   /* This bit is the same as expand_builtin_longjmp.  */
+  emit_clobber (gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode)));
+  emit_clobber (gen_rtx_MEM (BLKmode, hard_frame_pointer_rtx));
   emit_move_insn (hard_frame_pointer_rtx, fp);
   emit_move_insn (pv, lab);
   emit_stack_restore (SAVE_NONLOCAL, stack);