From 67b977ada8b0fece1138d67d2ebfbf2e9b030d01 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Mon, 13 Feb 2012 21:14:25 +0100 Subject: [PATCH] cselib.c (expand_loc): Return sp, fp, hfp or cfa base reg right away if seen. * cselib.c (expand_loc): Return sp, fp, hfp or cfa base reg right away if seen. From-SVN: r184169 --- gcc/ChangeLog | 3 +++ gcc/cselib.c | 12 +++++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 58208ed..7a469e4 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,8 @@ 2012-02-13 Jakub Jelinek + * cselib.c (expand_loc): Return sp, fp, hfp or cfa base reg right + away if seen. + * cselib.c (dump_cselib_val): Don't assume l->setting_insn is non-NULL. diff --git a/gcc/cselib.c b/gcc/cselib.c index 456c875..7d3e4ca 100644 --- a/gcc/cselib.c +++ b/gcc/cselib.c @@ -1372,8 +1372,18 @@ expand_loc (struct elt_loc_list *p, struct expand_value_data *evd, unsigned int regno = UINT_MAX; struct elt_loc_list *p_in = p; - for (; p; p = p -> next) + for (; p; p = p->next) { + /* Return these right away to avoid returning stack pointer based + expressions for frame pointer and vice versa, which is something + that would confuse DSE. See the comment in cselib_expand_value_rtx_1 + for more details. */ + if (REG_P (p->loc) + && (REGNO (p->loc) == STACK_POINTER_REGNUM + || REGNO (p->loc) == FRAME_POINTER_REGNUM + || REGNO (p->loc) == HARD_FRAME_POINTER_REGNUM + || REGNO (p->loc) == cfa_base_preserved_regno)) + return p->loc; /* Avoid infinite recursion trying to expand a reg into a the same reg. */ if ((REG_P (p->loc)) -- 2.7.4