On 01/08/14 01:14, Eric Botcazou wrote:
Committed after private email approval from Jakub. I made one
additional trivial change (missing whitespace in a comment).
This breaks bootstrap with RTL checking enabled:
/home/eric/svn/gcc/libgcc/config/libbid/bid64_noncomp.c:119:1: internal
compiler error: RTL check: expected code 'set' or 'clobber', have 'parallel'
in combine_reaching_defs, at ree.c:711
There were two issues in that code. The first assumed the form of
DEF_INSN was (set (dest) (src)), the second assumed that the destination
must be a reg before checking its REGNO.
ree.c already had some code which effectively defined the form that the
defining insn could take. It's not quite "single_set", though I'd
really prefer that be the form in the future. Anyway, I pulled that
code out of merge_def_and_ext so that it could also be used by
combine_reaching_defs.
With that I was able to bootstrap & regression test with
--enable-checking=rtl as well as a normal bootstrap and regression test
on x86_64-unknown-linux-gnu.
OK for the trunk?
* ree.c (get_sub_rtx): New function, extracted from...
(merge_def_and_ext): Here.
(combine_reaching_defs): Use get_sub_rtx.
diff --git a/gcc/ree.c b/gcc/ree.c
index ec09c7a..b41e891 100644
--- a/gcc/ree.c
+++ b/gcc/ree.c
@@ -580,27 +580,17 @@ make_defs_and_copies_lists (rtx extend_insn, const_rtx
set_pat,
return ret;
}
-/* Merge the DEF_INSN with an extension. Calls combine_set_extension
- on the SET pattern. */
-
-static bool
-merge_def_and_ext (ext_cand *cand, rtx def_insn, ext_state *state)
+static rtx *
+get_sub_rtx (rtx def_insn)
{
- enum machine_mode ext_src_mode;
- enum rtx_code code;
- rtx *sub_rtx;
- rtx s_expr;
- int i;
-
- ext_src_mode = GET_MODE (XEXP (SET_SRC (cand->expr), 0));
- code = GET_CODE (PATTERN (def_insn));
- sub_rtx = NULL;
+ enum rtx_code code = GET_CODE (PATTERN (def_insn));
+ rtx *sub_rtx = NULL;
if (code == PARALLEL)
{
- for (i = 0; i < XVECLEN (PATTERN (def_insn), 0); i++)
+ for (int i = 0; i < XVECLEN (PATTERN (def_insn), 0); i++)
{
- s_expr = XVECEXP (PATTERN (def_insn), 0, i);
+ rtx s_expr = XVECEXP (PATTERN (def_insn), 0, i);
if (GET_CODE (s_expr) != SET)
continue;
@@ -609,7 +599,7 @@ merge_def_and_ext (ext_cand *cand, rtx def_insn, ext_state
*state)
else
{
/* PARALLEL with multiple SETs. */
- return false;
+ return NULL;
}
}
}
@@ -618,10 +608,27 @@ merge_def_and_ext (ext_cand *cand, rtx def_insn,
ext_state *state)
else
{
/* It is not a PARALLEL or a SET, what could it be ? */
- return false;
+ return NULL;
}
gcc_assert (sub_rtx != NULL);
+ return sub_rtx;
+}
+
+/* Merge the DEF_INSN with an extension. Calls combine_set_extension
+ on the SET pattern. */
+
+static bool
+merge_def_and_ext (ext_cand *cand, rtx def_insn, ext_state *state)
+{
+ enum machine_mode ext_src_mode;
+ rtx *sub_rtx;
+
+ ext_src_mode = GET_MODE (XEXP (SET_SRC (cand->expr), 0));
+ sub_rtx = get_sub_rtx (def_insn);
+
+ if (sub_rtx == NULL)
+ return false;
if (REG_P (SET_DEST (*sub_rtx))
&& (GET_MODE (SET_DEST (*sub_rtx)) == ext_src_mode
@@ -707,8 +714,13 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat,
ext_state *state)
/* If there is an overlap between the destination of DEF_INSN and
CAND->insn, then this transformation is not safe. Note we have
to test in the widened mode. */
+ rtx *dest_sub_rtx = get_sub_rtx (def_insn);
+ if (dest_sub_rtx == NULL
+ || !REG_P (SET_DEST (*dest_sub_rtx)))
+ return false;
+
rtx tmp_reg = gen_rtx_REG (GET_MODE (SET_DEST (PATTERN (cand->insn))),
- REGNO (SET_DEST (PATTERN (def_insn))));
+ REGNO (SET_DEST (*dest_sub_rtx)));
if (reg_overlap_mentioned_p (tmp_reg, SET_DEST (PATTERN (cand->insn))))
return false;