From 73168547c7777ca50db232abd1c51219bb6a8c2a Mon Sep 17 00:00:00 2001 From: Iain Sandoe Date: Sun, 1 Sep 2013 15:39:28 +0000 Subject: [PATCH] backport: re PR target/51784 (PIC register not correctly preserved in nested funcs / with non-local goto) gcc: Backport from mainline: 2013-07-22 Uros Bizjak * config/i386/i386.md (nonlocal_goto_receiver): Delete insn if it is not needed after split. 2013-07-20 Iain Sandoe PR target/51784 * config/i386/i386.c (output_set_got) [TARGET_MACHO]: Adjust to emit a second label for nonlocal goto receivers. Don't output pic base labels unless we're producing PIC; mark that action unreachable(). (ix86_save_reg): If the function contains a nonlocal label, save the PIC base reg. * config/darwin-protos.h (machopic_should_output_picbase_label): New. * gcc/config/darwin.c (emitted_pic_label_num): New GTY. (update_pic_label_number_if_needed): New. (machopic_output_function_base_name): Adjust for nonlocal receiver case. (machopic_should_output_picbase_label): New. * config/i386/i386.md (enum unspecv): UNSPECV_NLGR: New. (nonlocal_goto_receiver): New insn and split. From-SVN: r202147 --- gcc/ChangeLog | 25 +++++++++++++++++++++++++ gcc/config/darwin-protos.h | 1 + gcc/config/darwin.c | 30 +++++++++++++++++++++++++----- gcc/config/i386/i386.c | 30 ++++++++++++++++-------------- gcc/config/i386/i386.md | 37 +++++++++++++++++++++++++++++++++++-- 5 files changed, 102 insertions(+), 21 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index aafd0bdf8434..015e4a99b3b0 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,28 @@ +2013-09-01 Iain Sandoe + + Backport from mainline: + 2013-07-22 Uros Bizjak + + * config/i386/i386.md (nonlocal_goto_receiver): Delete insn if + it is not needed after split. + + 2013-07-20 Iain Sandoe + + PR target/51784 + * config/i386/i386.c (output_set_got) [TARGET_MACHO]: Adjust to emit a + second label for nonlocal goto receivers. Don't output pic base labels + unless we're producing PIC; mark that action unreachable(). + (ix86_save_reg): If the function contains a nonlocal label, save the + PIC base reg. + * config/darwin-protos.h (machopic_should_output_picbase_label): New. + * gcc/config/darwin.c (emitted_pic_label_num): New GTY. + (update_pic_label_number_if_needed): New. + (machopic_output_function_base_name): Adjust for nonlocal receiver + case. + (machopic_should_output_picbase_label): New. + * config/i386/i386.md (enum unspecv): UNSPECV_NLGR: New. + (nonlocal_goto_receiver): New insn and split. + 2013-08-28 Uros Bizjak Backport from mainline diff --git a/gcc/config/darwin-protos.h b/gcc/config/darwin-protos.h index e0220864facf..bb487e066c50 100644 --- a/gcc/config/darwin-protos.h +++ b/gcc/config/darwin-protos.h @@ -26,6 +26,7 @@ extern void machopic_validate_stub_or_non_lazy_ptr (const char *); extern void machopic_output_function_base_name (FILE *); extern const char *machopic_indirection_name (rtx, bool); extern const char *machopic_mcount_stub_name (void); +extern bool machopic_should_output_picbase_label (void); #ifdef RTX_CODE diff --git a/gcc/config/darwin.c b/gcc/config/darwin.c index 63684e3a02cd..aec3d13d6d95 100644 --- a/gcc/config/darwin.c +++ b/gcc/config/darwin.c @@ -362,14 +362,13 @@ machopic_gen_offset (rtx orig) static GTY(()) const char * function_base_func_name; static GTY(()) int current_pic_label_num; +static GTY(()) int emitted_pic_label_num; -void -machopic_output_function_base_name (FILE *file) +static void +update_pic_label_number_if_needed (void) { const char *current_name; - /* If dynamic-no-pic is on, we should not get here. */ - gcc_assert (!MACHO_DYNAMIC_NO_PIC_P); /* When we are generating _get_pc thunks within stubs, there is no current function. */ if (current_function_decl) @@ -387,7 +386,28 @@ machopic_output_function_base_name (FILE *file) ++current_pic_label_num; function_base_func_name = "L_machopic_stub_dummy"; } - fprintf (file, "L%011d$pb", current_pic_label_num); +} + +void +machopic_output_function_base_name (FILE *file) +{ + /* If dynamic-no-pic is on, we should not get here. */ + gcc_assert (!MACHO_DYNAMIC_NO_PIC_P); + + update_pic_label_number_if_needed (); + fprintf (file, "L%d$pb", current_pic_label_num); +} + +bool +machopic_should_output_picbase_label (void) +{ + update_pic_label_number_if_needed (); + + if (current_pic_label_num == emitted_pic_label_num) + return false; + + emitted_pic_label_num = current_pic_label_num; + return true; } /* The suffix attached to non-lazy pointer symbols. */ diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index a6b53e99e546..51d5120daced 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -8613,17 +8613,12 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED) if (!flag_pic) { - xops[2] = gen_rtx_LABEL_REF (Pmode, label ? label : gen_label_rtx ()); + if (TARGET_MACHO) + /* We don't need a pic base, we're not producing pic. */ + gcc_unreachable (); + xops[2] = gen_rtx_LABEL_REF (Pmode, label ? label : gen_label_rtx ()); output_asm_insn ("mov%z0\t{%2, %0|%0, %2}", xops); - -#if TARGET_MACHO - /* Output the Mach-O "canonical" label name ("Lxx$pb") here too. This - is what will be referenced by the Mach-O PIC subsystem. */ - if (!label) - ASM_OUTPUT_LABEL (asm_out_file, MACHOPIC_FUNCTION_BASE_NAME); -#endif - targetm.asm_out.internal_label (asm_out_file, "L", CODE_LABEL_NUMBER (XEXP (xops[2], 0))); } @@ -8636,12 +8631,18 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED) xops[2] = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (name)); xops[2] = gen_rtx_MEM (QImode, xops[2]); output_asm_insn ("call\t%X2", xops); - /* Output the Mach-O "canonical" label name ("Lxx$pb") here too. This - is what will be referenced by the Mach-O PIC subsystem. */ + #if TARGET_MACHO - if (!label) + /* Output the Mach-O "canonical" pic base label name ("Lxx$pb") here. + This is what will be referenced by the Mach-O PIC subsystem. */ + if (machopic_should_output_picbase_label () || !label) ASM_OUTPUT_LABEL (asm_out_file, MACHOPIC_FUNCTION_BASE_NAME); - else + + /* When we are restoring the pic base at the site of a nonlocal label, + and we decided to emit the pic base above, we will still output a + local label used for calculating the correction offset (even though + the offset will be 0 in that case). */ + if (label) targetm.asm_out.internal_label (asm_out_file, "L", CODE_LABEL_NUMBER (label)); #endif @@ -8717,7 +8718,8 @@ ix86_save_reg (unsigned int regno, bool maybe_eh_return) && (df_regs_ever_live_p (REAL_PIC_OFFSET_TABLE_REGNUM) || crtl->profile || crtl->calls_eh_return - || crtl->uses_const_pool)) + || crtl->uses_const_pool + || cfun->has_nonlocal_label)) return ix86_select_alt_pic_regnum () == INVALID_REGNUM; if (crtl->calls_eh_return && maybe_eh_return) diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index f6124c2cf0df..747a68ef662e 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -202,7 +202,10 @@ ;; For RDRAND support UNSPECV_RDRAND -]) + + ;; Non-local goto. + UNSPECV_NLGR + ]) ;; Constants to represent rounding modes in the ROUND instruction (define_constants @@ -16801,7 +16804,37 @@ emit_insn (gen_set_got (pic_offset_table_rtx)); DONE; }) - + +(define_insn_and_split "nonlocal_goto_receiver" + [(unspec_volatile [(const_int 0)] UNSPECV_NLGR)] + "TARGET_MACHO && !TARGET_64BIT && flag_pic" + "#" + "&& reload_completed" + [(const_int 0)] +{ + if (crtl->uses_pic_offset_table) + { + rtx xops[3]; + rtx label_rtx = gen_label_rtx (); + rtx tmp; + + /* Get a new pic base. */ + emit_insn (gen_set_got_labelled (pic_offset_table_rtx, label_rtx)); + /* Correct this with the offset from the new to the old. */ + xops[0] = xops[1] = pic_offset_table_rtx; + label_rtx = gen_rtx_LABEL_REF (SImode, label_rtx); + tmp = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, label_rtx), + UNSPEC_MACHOPIC_OFFSET); + xops[2] = gen_rtx_CONST (Pmode, tmp); + ix86_expand_binary_operator (MINUS, SImode, xops); + } + else + /* No pic reg restore needed. */ + emit_note (NOTE_INSN_DELETED); + + DONE; +}) + ;; Avoid redundant prefixes by splitting HImode arithmetic to SImode. (define_split -- 2.47.2