From 2fdad8af6daf385ab688ba5465442fe943187b84 Mon Sep 17 00:00:00 2001 From: Keith Randall Date: Mon, 30 Oct 2023 13:23:00 -0700 Subject: [release-branch.go1.21] cmd/internal/obj/arm64: fix frame pointer restore in epilogue For leaf but nonzero-frame functions. Currently we're not restoring it properly. We also need to restore it before popping the stack frame, so that the frame won't get clobbered by a signal handler in the meantime. For #63830 Fixes #65449 Needs a test, but I'm not at all sure how we would actually do that. Leaving for inspiration. Change-Id: I273a25f2a838f05a959c810145cccc5428eaf164 Reviewed-on: https://go-review.googlesource.com/c/go/+/538635 Reviewed-by: Cherry Mui Reviewed-by: Eric Fang LUCI-TryBot-Result: Go LUCI Reviewed-by: David Chase (cherry picked from commit c9888bdfe2cdd85d14d7d184863d2e8bc42ff73c) Reviewed-on: https://go-review.googlesource.com/c/go/+/560735 TryBot-Bypass: Michael Knyszek Reviewed-by: Keith Randall --- src/cmd/internal/obj/arm64/obj7.go | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/src/cmd/internal/obj/arm64/obj7.go b/src/cmd/internal/obj/arm64/obj7.go index f963f62dcd..f7cca30717 100644 --- a/src/cmd/internal/obj/arm64/obj7.go +++ b/src/cmd/internal/obj/arm64/obj7.go @@ -826,21 +826,24 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) { p.To = obj.Addr{} if c.cursym.Func().Text.Mark&LEAF != 0 { if c.autosize != 0 { + // Restore frame pointer. + // ADD $framesize-8, RSP, R29 p.As = AADD p.From.Type = obj.TYPE_CONST - p.From.Offset = int64(c.autosize) + p.From.Offset = int64(c.autosize) - 8 + p.Reg = REGSP p.To.Type = obj.TYPE_REG - p.To.Reg = REGSP - p.Spadj = -c.autosize + p.To.Reg = REGFP - // Frame pointer. + // Pop stack frame. + // ADD $framesize, RSP, RSP p = obj.Appendp(p, c.newprog) - p.As = ASUB + p.As = AADD p.From.Type = obj.TYPE_CONST - p.From.Offset = 8 - p.Reg = REGSP + p.From.Offset = int64(c.autosize) p.To.Type = obj.TYPE_REG - p.To.Reg = REGFP + p.To.Reg = REGSP + p.Spadj = -c.autosize } } else { aoffset := c.autosize -- cgit v1.2.3-54-g00ecf