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| author | Jakub Jelinek <jakub@redhat.com> | 2022-12-16 10:19:22 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2023-02-10 13:46:30 +0100 |
| commit | 4db6e1bf2f1647521dcd709bc3673f565fc327a5 (patch) | |
| tree | da7d9253a918e694013bd568853d3e76c9d64f1c /gcc | |
| parent | bc1ee711eeab4b0d55463cd153747d30c69225c7 (diff) | |
| download | gcc-4db6e1bf2f1647521dcd709bc3673f565fc327a5.zip gcc-4db6e1bf2f1647521dcd709bc3673f565fc327a5.tar.gz gcc-4db6e1bf2f1647521dcd709bc3673f565fc327a5.tar.bz2 | |
loop-invariant: Split preheader edge if the preheader bb ends with jump [PR106751]
The RTL loop passes only request simple preheaders, but don't require
fallthru preheaders, while move_invariant_reg apparently assumes the
latter, that it can just append instruction(s) to the end of the preheader
basic block.
The following patch fixes that by splitting the preheader edge if
the preheader bb ends with a JUMP_INSN (asm goto in this case).
Without that we get control flow in the middle of a bb.
2022-12-16 Jakub Jelinek <jakub@redhat.com>
PR rtl-optimization/106751
* loop-invariant.cc (move_invariant_reg): If preheader bb ends
with a JUMP_INSN, split the preheader edge and emit invariants
into the new preheader basic block.
* gcc.c-torture/compile/pr106751.c: New test.
(cherry picked from commit ddcaa60983b50378bde1b7e327086fe0ce101795)
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/loop-invariant.cc | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.c-torture/compile/pr106751.c | 17 |
2 files changed, 19 insertions, 0 deletions
diff --git a/gcc/loop-invariant.cc b/gcc/loop-invariant.cc index f324854..9b5f6cd 100644 --- a/gcc/loop-invariant.cc +++ b/gcc/loop-invariant.cc @@ -1837,6 +1837,8 @@ move_invariant_reg (class loop *loop, unsigned invno) else if (dump_file) fprintf (dump_file, "Invariant %d moved without introducing a new " "temporary register\n", invno); + if (JUMP_P (BB_END (preheader))) + preheader = split_edge (loop_preheader_edge (loop)); reorder_insns (inv->insn, inv->insn, BB_END (preheader)); df_recompute_luids (preheader); diff --git a/gcc/testsuite/gcc.c-torture/compile/pr106751.c b/gcc/testsuite/gcc.c-torture/compile/pr106751.c new file mode 100644 index 0000000..5fbf93b --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/pr106751.c @@ -0,0 +1,17 @@ +/* PR rtl-optimization/106751 */ + +int *foo (void); + +void +bar (void) +{ + asm goto ("" : : : : lab); + __builtin_unreachable (); +lab: + while (1) + { + int o; + asm ("" : "=r" (o) : "g" (1)); + *foo () = o; + } +} |