From: Segher Boessenkool Date: Wed, 9 May 2018 12:51:00 +0000 (+0200) Subject: rs6000: Give an argument to every REG_CFA_REGISTER (PR85645) X-Git-Tag: basepoints/gcc-10~6910 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cd9ba4ca3051a5ca411f9d333f2a4cc170136740;p=thirdparty%2Fgcc.git 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 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1c81e4f55529..0acd815b35c8 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 6fb79f29a625..19913da9584a 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)); }