diff options
| author | Jakub Jelinek <jakub@redhat.com> | 2023-01-03 12:12:35 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2023-01-03 12:12:35 +0100 |
| commit | 4fb639a7fee5df32a2d1e7afa40fdf31d280464b (patch) | |
| tree | a9a9bfea30476fc781043db1c39b9b6c96b50783 /gcc | |
| parent | 201c21b0e847679645df1af3dd13459274f41047 (diff) | |
| download | gcc-4fb639a7fee5df32a2d1e7afa40fdf31d280464b.zip gcc-4fb639a7fee5df32a2d1e7afa40fdf31d280464b.tar.gz gcc-4fb639a7fee5df32a2d1e7afa40fdf31d280464b.tar.bz2 | |
cfgrtl: Don't try to redirect asm goto to EXIT [PR108263]
The following testcase distilled from Linux kernel on ppc64le ICEs,
because fixup_reorder_chain sees a bb with a single fallthru edge
falling into a bb with simple return and decides to redirect
that fallthru edge to EXIT. That is possible if the bb ending
in the fallthru edge doesn't end with a jump or ends with a normal
unconditional jump, but not when the bb ends with asm goto which can despite
a single fallthru have multiple labels to the fallthrough basic block.
The following patch makes sure we never try to redirect such cases to EXIT.
2023-01-03 Jakub Jelinek <jakub@redhat.com>
PR rtl-optimization/108263
* cfgrtl.cc (fixup_reorder_chain): Avoid trying to redirect
asm goto to EXIT.
* gcc.dg/pr108263.c: New test.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cfgrtl.cc | 8 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr108263.c | 25 |
2 files changed, 31 insertions, 2 deletions
diff --git a/gcc/cfgrtl.cc b/gcc/cfgrtl.cc index fcc2edb..1d84b29 100644 --- a/gcc/cfgrtl.cc +++ b/gcc/cfgrtl.cc @@ -3910,6 +3910,7 @@ fixup_reorder_chain (void) rtx ret_label = NULL_RTX; basic_block nb; edge_iterator ei; + bool asm_goto = false; if (EDGE_COUNT (bb->succs) == 0) continue; @@ -4016,7 +4017,9 @@ fixup_reorder_chain (void) || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) continue; - /* Otherwise we'll have to use the fallthru fixup below. */ + /* Otherwise we'll have to use the fallthru fixup below. + But avoid redirecting asm goto to EXIT. */ + asm_goto = true; } else { @@ -4048,7 +4051,8 @@ fixup_reorder_chain (void) return rather than a jump to the return block. */ rtx_insn *ret, *use; basic_block dest; - if (bb_is_just_return (e_fall->dest, &ret, &use) + if (!asm_goto + && bb_is_just_return (e_fall->dest, &ret, &use) && ((PATTERN (ret) == simple_return_rtx && targetm.have_simple_return ()) || (PATTERN (ret) == ret_rtx && targetm.have_return ()))) { diff --git a/gcc/testsuite/gcc.dg/pr108263.c b/gcc/testsuite/gcc.dg/pr108263.c new file mode 100644 index 0000000..688df32 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr108263.c @@ -0,0 +1,25 @@ +/* PR rtl-optimization/108263 */ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ + +int v, *p; + +void +foo (void) +{ + int i; + for (i = 0; ; i++) + { + if (v) + { + __label__ l1; + asm goto ("" : : : : l1); + l1: + return; + } + if (p[i]) + break; + } + asm goto ("" : : "r" (i) : : l2); +l2:; +} |