Hi!
Regardless of the outcome of the general-regs-only stuff in x86gprintrin.h,
apparently general-regs-only is much bigger hammer than no-sse, and e.g.
using 387 instructions in the unwinder isn't a big deal, it never needs
to realign the stack because of it.
So, the following patch uses no-sse (and adds no-mmx to it, even when not
strictly needed).
Bootstrapped/regtested on x86_64-linux and i686-linux, on the latter
both normally and with -msse2 -mfpmath=sse -mstackrealign in the options and
--enable-cet, ok for trunk?
2022-03-15 Jakub Jelinek <ja...@redhat.com>
PR target/104890
* config/i386/i386.h (LIBGCC2_UNWIND_ATTRIBUTE): Use no-mmx,no-sse
instead of general-regs-only.
--- gcc/config/i386/i386.h.jj 2022-03-09 15:25:28.355498493 +0100
+++ gcc/config/i386/i386.h 2022-03-14 15:27:33.831976579 +0100
@@ -2848,10 +2848,10 @@ extern enum attr_cpu ix86_schedule;
#define NUM_X86_64_MS_CLOBBERED_REGS 12
#endif
-/* __builtin_eh_return can't handle stack realignment, so restrict to
- general regs in 32-bit libgcc functions that call it. */
+/* __builtin_eh_return can't handle stack realignment, so disable MMX/SSE
+ in 32-bit libgcc functions that call it. */
#ifndef __x86_64__
-#define LIBGCC2_UNWIND_ATTRIBUTE __attribute__((target ("general-regs-only")))
+#define LIBGCC2_UNWIND_ATTRIBUTE __attribute__((target ("no-mmx,no-sse")))
#endif
/*
Jakub
