Hi,
I plan to backport the patch to fix PR100775: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100775 To gcc11 since this is a general bug to -fzero-call-used-regs. And should be fixed in gcc11 as well. I have tested the patch with gcc11 release branch on both x86 and aarch64, no regression. Okay for commit? thanks. Qing. ================================================== >From 737a0ccccb0824111f46da44c5578b9769070c52 Mon Sep 17 00:00:00 2001 From: Qing Zhao <qing.z...@oracle.com> Date: Thu, 10 Mar 2022 23:22:29 +0000 Subject: [PATCH] middle-end: updating the reg use in exit block for -fzero-call-used-regs [PR100775] GCC11 backport. In the pass_zero_call_used_regs, when updating dataflow info after adding the register zeroing sequence in the epilogue of the function, we should call "df_update_exit_block_uses" to update the register use information in the exit block to include all the registers that have been zeroed. gcc/ChangeLog: PR middle-end/100775 * function.c (gen_call_used_regs_seq): Call df_update_exit_block_uses when updating df. gcc/testsuite/ChangeLog: PR middle-end/100775 * gcc.target/arm/pr100775.c: New test. --- gcc/function.c | 2 +- gcc/testsuite/gcc.target/arm/pr100775.c | 9 +++++++++ 2 files changed, 10 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.target/arm/pr100775.c diff --git a/gcc/function.c b/gcc/function.c index fc7b147b5f1..0495e9f1b81 100644 --- a/gcc/function.c +++ b/gcc/function.c @@ -5922,7 +5922,7 @@ gen_call_used_regs_seq (rtx_insn *ret, unsigned int zero_regs_type) /* Update the data flow information. */ crtl->must_be_zero_on_return |= zeroed_hardregs; - df_set_bb_dirty (EXIT_BLOCK_PTR_FOR_FN (cfun)); + df_update_exit_block_uses (); } } diff --git a/gcc/testsuite/gcc.target/arm/pr100775.c b/gcc/testsuite/gcc.target/arm/pr100775.c new file mode 100644 index 00000000000..c648cd5e8f7 --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/pr100775.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-skip-if "" { ! { arm_thumb1_ok || arm_thumb2_ok } } } */ +/* { dg-options "-mthumb -fzero-call-used-regs=used" } */ + +int +foo (int x) +{ + return x; +} -- 2.27.0
