From 9b747072b98c6f8a0ffb058e89b45d36b47152cc Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Sat, 9 Feb 2019 08:50:58 +1030 Subject: [PATCH] [RS6000] Correct save_reg_p Fixes lack of r30 save/restore on // -m32 -fpic -ftls-model=initial-exec __thread char* p; char** f1 (void) { return &p; } and // -m32 -fpic -msecure-plt extern int foo (int); int f1 (int x) { return foo (x); } These are both caused by save_reg_p returning false when the pic offset table reg (r30 for ABI_V4) was used, due to the logic not exactly matching that in rs6000_emit_prologue to set up r30. I also noticed that save_reg_p isn't following the comment regarding calls_eh_return (since svn 267049, git 0edf78b1b2a0), and the comment needs tweaking too. For why the revised comment is correct, grep for saves_all_registers in lra.c, and yes, we do want to save the pic offset table reg for eh_return. PR target/88343 * config/rs6000/rs6000.c (save_reg_p): Correct calls_eh_return case. Match logic in rs6000_emit_prologue emitting pic_offset_table setup. From-SVN: r268708 --- gcc/ChangeLog | 7 +++++++ gcc/config/rs6000/rs6000.c | 25 +++++++++++++++++-------- 2 files changed, 24 insertions(+), 8 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9e5a140b0e1..0079a6948e8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2019-02-09 Alan Modra + + PR target/88343 + * config/rs6000/rs6000.c (save_reg_p): Correct calls_eh_return + case. Match logic in rs6000_emit_prologue emitting pic_offset_table + setup. + 2019-02-08 Vladimir Makarov PR middle-end/88560 diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c index 711278c7422..b4ff18d414c 100644 --- a/gcc/config/rs6000/rs6000.c +++ b/gcc/config/rs6000/rs6000.c @@ -24008,21 +24008,30 @@ rs6000_split_multireg_move (rtx dst, rtx src) static bool save_reg_p (int reg) { - /* We need to mark the PIC offset register live for the same conditions - as it is set up, or otherwise it won't be saved before we clobber it. */ - if (reg == RS6000_PIC_OFFSET_TABLE_REGNUM && !TARGET_SINGLE_PIC_BASE) { /* When calling eh_return, we must return true for all the cases where conditional_register_usage marks the PIC offset reg - call used. */ + call used or fixed. */ + if (crtl->calls_eh_return + && ((DEFAULT_ABI == ABI_V4 && flag_pic) + || (DEFAULT_ABI == ABI_DARWIN && flag_pic) + || (TARGET_TOC && TARGET_MINIMAL_TOC))) + return true; + + /* We need to mark the PIC offset register live for the same + conditions as it is set up in rs6000_emit_prologue, or + otherwise it won't be saved before we clobber it. */ if (TARGET_TOC && TARGET_MINIMAL_TOC - && (crtl->calls_eh_return - || df_regs_ever_live_p (reg) - || !constant_pool_empty_p ())) + && !constant_pool_empty_p ()) + return true; + + if (DEFAULT_ABI == ABI_V4 + && (flag_pic == 1 || (flag_pic && TARGET_SECURE_PLT)) + && df_regs_ever_live_p (RS6000_PIC_OFFSET_TABLE_REGNUM)) return true; - if ((DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_DARWIN) + if (DEFAULT_ABI == ABI_DARWIN && flag_pic && crtl->uses_pic_offset_table) return true; } -- 2.30.2