From 803d222e533efbc385411d4b5a2d0ec0551b9f16 Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Thu, 21 Dec 2023 10:20:19 +0000 Subject: aarch64: Fix early RA handling of deleted insns [PR113094] The testcase constructs a sequence of insns that are fully dead and yet (due to forced options) are not removed as such. This triggered a case where we would emit a meaningless reload for a to-be-deleted insn. We can't delete the insns first because that might disrupt the iteration ranges. So this patch turns them into notes before the walk and then continues to delete them properly afterwards. gcc/ PR target/113094 * config/aarch64/aarch64-early-ra.cc (apply_allocation): Stub out instructions that are going to be deleted before iterating over the rest. gcc/testsuite/ PR target/113094 * gcc.target/aarch64/pr113094.c: New test. --- gcc/config/aarch64/aarch64-early-ra.cc | 3 +++ gcc/testsuite/gcc.target/aarch64/pr113094.c | 10 ++++++++++ 2 files changed, 13 insertions(+) create mode 100644 gcc/testsuite/gcc.target/aarch64/pr113094.c (limited to 'gcc') diff --git a/gcc/config/aarch64/aarch64-early-ra.cc b/gcc/config/aarch64/aarch64-early-ra.cc index 24415bd..5d2da3e 100644 --- a/gcc/config/aarch64/aarch64-early-ra.cc +++ b/gcc/config/aarch64/aarch64-early-ra.cc @@ -3210,6 +3210,9 @@ early_ra::maybe_convert_to_strided_access (rtx_insn *insn) void early_ra::apply_allocation () { + for (auto *insn : m_dead_insns) + set_insn_deleted (insn); + rtx_insn *prev; for (auto insn_range : m_insn_ranges) for (rtx_insn *insn = insn_range.first; diff --git a/gcc/testsuite/gcc.target/aarch64/pr113094.c b/gcc/testsuite/gcc.target/aarch64/pr113094.c new file mode 100644 index 0000000..b79e1f7 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/pr113094.c @@ -0,0 +1,10 @@ +/* { dg-options "-fno-tree-dse -Ofast -fno-tree-coalesce-vars -fno-dce -fno-tree-dce" } */ + +struct TV4 { + __attribute__((vector_size(sizeof(int) * 4))) int v; +}; +void modify() { + struct TV4 __trans_tmp_1, temp; + temp.v[0] = temp.v[3] = 0; + __trans_tmp_1 = temp; +} -- cgit v1.1