PR rtl-optimization/106421: ICE in bypass_block from non-local goto.
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Commit Message
This patch fixes PR rtl-optimization/106421, an ICE-on-valid (but
undefined) regression. The fix, as proposed by Richard Biener, is to
defend against BLOCK_FOR_INSN returning NULL in cprop's bypass_block.
This patch has been tested on x86_64-pc-linux-gnu with make bootstrap
and make -k check, both with and without --target_board=unix{-m32},
with no new failures. Ok for mainline?
2023-01-09 Roger Sayle <roger@nextmovesoftware.com>
gcc/ChangeLog
PR rtl-optimization/106421
* cprop.cc (bypass_block): Check that DEST is local to this
function (non-NULL) before calling find_edge.
gcc/testsuite/ChangeLog
PR rtl-optimization/106421
* gcc.dg/pr106421.c: New test case.
Thanks in advance,
Roger
--
Comments
On Mon, Jan 9, 2023 at 8:50 PM Roger Sayle <roger@nextmovesoftware.com> wrote:
>
>
> This patch fixes PR rtl-optimization/106421, an ICE-on-valid (but
> undefined) regression. The fix, as proposed by Richard Biener, is to
> defend against BLOCK_FOR_INSN returning NULL in cprop's bypass_block.
>
> This patch has been tested on x86_64-pc-linux-gnu with make bootstrap
> and make -k check, both with and without --target_board=unix{-m32},
> with no new failures. Ok for mainline?
OK.
>
> 2023-01-09 Roger Sayle <roger@nextmovesoftware.com>
>
> gcc/ChangeLog
> PR rtl-optimization/106421
> * cprop.cc (bypass_block): Check that DEST is local to this
> function (non-NULL) before calling find_edge.
>
> gcc/testsuite/ChangeLog
> PR rtl-optimization/106421
> * gcc.dg/pr106421.c: New test case.
>
>
> Thanks in advance,
> Roger
> --
>
@@ -1622,9 +1622,12 @@ bypass_block (basic_block bb, rtx_insn *setcc, rtx_insn *jump)
{
dest = BLOCK_FOR_INSN (XEXP (new_rtx, 0));
/* Don't bypass edges containing instructions. */
- edest = find_edge (bb, dest);
- if (edest && edest->insns.r)
- dest = NULL;
+ if (dest)
+ {
+ edest = find_edge (bb, dest);
+ if (edest && edest->insns.r)
+ dest = NULL;
+ }
}
else
dest = NULL;
new file mode 100644
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+int main(int argc, char **argv)
+{
+ __label__ loop, end;
+ void jmp(int c) { goto *(c ? &&loop : &&end); }
+loop:
+ jmp(argc < 0);
+end:
+ return 0;
+}
+