From cd9ba4ca3051a5ca411f9d333f2a4cc170136740 Mon Sep 17 00:00:00 2001 From: Segher Boessenkool Date: Wed, 9 May 2018 14:51:00 +0200 Subject: [PATCH] rs6000: Give an argument to every REG_CFA_REGISTER (PR85645) The one for the prologue mflr did not have any value set, which means use the SET that is in the insn pattern. This works fine, except when some late pass decides to replace the SET_SRC -- this changes the meaning of the REG_CFA_REGISTER! Such passes should not do these things, but let's be more explicit here, for extra robustness. It could be argued that this defaulting is a design misfeature (it does not save much space either, etc.) PR rtl-optimization/85645 * config/rs6000/rs6000.c (rs6000_emit_prologue_components): Put a SET in the REG_CFA_REGISTER note for LR, don't leave it empty. From-SVN: r260077 --- gcc/ChangeLog | 6 ++++++ gcc/config/rs6000/rs6000.c | 6 +++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1c81e4f5552..0acd815b35c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2018-05-09 Segher Boessenkool + + PR rtl-optimization/85645 + * config/rs6000/rs6000.c (rs6000_emit_prologue_components): Put a SET + in the REG_CFA_REGISTER note for LR, don't leave it empty. + 2018-05-09 Segher Boessenkool PR rtl-optimization/85645 diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c index 6fb79f29a62..19913da9584 100644 --- a/gcc/config/rs6000/rs6000.c +++ b/gcc/config/rs6000/rs6000.c @@ -26151,10 +26151,11 @@ rs6000_emit_prologue_components (sbitmap components) /* Prologue for LR. */ if (bitmap_bit_p (components, 0)) { + rtx lr = gen_rtx_REG (reg_mode, LR_REGNO); rtx reg = gen_rtx_REG (reg_mode, 0); - rtx_insn *insn = emit_move_insn (reg, gen_rtx_REG (reg_mode, LR_REGNO)); + rtx_insn *insn = emit_move_insn (reg, lr); RTX_FRAME_RELATED_P (insn) = 1; - add_reg_note (insn, REG_CFA_REGISTER, NULL); + add_reg_note (insn, REG_CFA_REGISTER, gen_rtx_SET (reg, lr)); int offset = info->lr_save_offset; if (info->push_p) @@ -26162,7 +26163,6 @@ rs6000_emit_prologue_components (sbitmap components) insn = emit_insn (gen_frame_store (reg, ptr_reg, offset)); RTX_FRAME_RELATED_P (insn) = 1; - rtx lr = gen_rtx_REG (reg_mode, LR_REGNO); rtx mem = copy_rtx (SET_DEST (single_set (insn))); add_reg_note (insn, REG_CFA_OFFSET, gen_rtx_SET (mem, lr)); } -- 2.30.2