From: Richard Sandiford <richard.sandif...@arm.com>
The prologue/epilogue pass allows the prologue sequence
to contain jumps. The sequence is then partitioned into
basic blocks using find_many_sub_basic_blocks.
This patch treats epilogues in the same way. It's needed for
a follow-on aarch64 patch that adds conditional code to both
the prologue and the epilogue.
Tested on aarch64-linux-gnu (including with a follow-on patch)
and x86_64-linux-gnu. OK to install?
Richard
gcc/
* function.cc (thread_prologue_and_epilogue_insns): Handle
epilogues that contain jumps.
---
This is a previously approved patch that was not committed
because it was not needed at the time, but i'd like to commit
it as it is needed for the followup aarch64 eh_return changes:
https://gcc.gnu.org/pipermail/gcc-patches/2022-November/605769.html
---
gcc/function.cc | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/gcc/function.cc b/gcc/function.cc
index dd2c1136e07..70d1cd65303 100644
--- a/gcc/function.cc
+++ b/gcc/function.cc
@@ -6120,6 +6120,11 @@ thread_prologue_and_epilogue_insns (void)
&& returnjump_p (BB_END (e->src)))
e->flags &= ~EDGE_FALLTHRU;
}
+
+ auto_sbitmap blocks (last_basic_block_for_fn (cfun));
+ bitmap_clear (blocks);
+ bitmap_set_bit (blocks, BLOCK_FOR_INSN (epilogue_seq)->index);
+ find_many_sub_basic_blocks (blocks);
}
else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
{
@@ -6218,6 +6223,11 @@ thread_prologue_and_epilogue_insns (void)
set_insn_locations (seq, epilogue_location);
emit_insn_before (seq, insn);
+
+ auto_sbitmap blocks (last_basic_block_for_fn (cfun));
+ bitmap_clear (blocks);
+ bitmap_set_bit (blocks, BLOCK_FOR_INSN (insn)->index);
+ find_many_sub_basic_blocks (blocks);
}
}
--
2.25.1
