From 92383fee5c764578927b7a3f559c50c28ad395f4 Mon Sep 17 00:00:00 2001 From: Georg-Johann Lay Date: Mon, 10 Jul 2017 08:22:47 +0000 Subject: [PATCH] Move jump-tables out of .text again. gcc/ Move jump-tables out of .text again. PR target/81075 * config/avr/avr.c (ASM_OUTPUT_ADDR_VEC_ELT): Remove function. (ASM_OUTPUT_ADDR_VEC): New function. (avr_adjust_insn_length) [JUMP_TABLE_DATA_P]: Return 0. (avr_final_prescan_insn) [avr_log.insn_addresses]: Dump INSN_ADDRESSes as asm comment. * config/avr/avr.h (JUMP_TABLES_IN_TEXT_SECTION): Adjust comment. (ASM_OUTPUT_ADDR_VEC_ELT): Remove define. (ASM_OUTPUT_ADDR_VEC): Define to avr_output_addr_vec. * config/avr/avr.md (*tablejump): Adjust comment. * config/avr/elf.h (ASM_OUTPUT_BEFORE_CASE_LABEL): Remove. * config/avr/avr-log.c (avr_log_set_avr_log) : New detail. * config/avr/avr-protos.h (avr_output_addr_vec_elt): Remove proto. (avr_output_addr_vec): New proto. (avr_log_t) : New field. From-SVN: r250091 --- gcc/ChangeLog | 21 +++++++++ gcc/config/avr/avr-log.c | 1 + gcc/config/avr/avr-protos.h | 3 +- gcc/config/avr/avr.c | 91 +++++++++++++++++++++++++++++++++++-- gcc/config/avr/avr.h | 8 +++- gcc/config/avr/avr.md | 2 +- gcc/config/avr/elf.h | 5 -- 7 files changed, 117 insertions(+), 14 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 2a0c6d6e007..8e71bc79359 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,24 @@ +2017-07-10 Georg-Johann Lay + + Move jump-tables out of .text again. + + PR target/81075 + * config/avr/avr.c (ASM_OUTPUT_ADDR_VEC_ELT): Remove function. + (ASM_OUTPUT_ADDR_VEC): New function. + (avr_adjust_insn_length) [JUMP_TABLE_DATA_P]: Return 0. + (avr_final_prescan_insn) [avr_log.insn_addresses]: Dump + INSN_ADDRESSes as asm comment. + * config/avr/avr.h (JUMP_TABLES_IN_TEXT_SECTION): Adjust comment. + (ASM_OUTPUT_ADDR_VEC_ELT): Remove define. + (ASM_OUTPUT_ADDR_VEC): Define to avr_output_addr_vec. + * config/avr/avr.md (*tablejump): Adjust comment. + * config/avr/elf.h (ASM_OUTPUT_BEFORE_CASE_LABEL): Remove. + * config/avr/avr-log.c (avr_log_set_avr_log) : + New detail. + * config/avr/avr-protos.h (avr_output_addr_vec_elt): Remove proto. + (avr_output_addr_vec): New proto. + (avr_log_t) : New field. + 2017-07-09 H.J. Lu PR target/81313 diff --git a/gcc/config/avr/avr-log.c b/gcc/config/avr/avr-log.c index 2b1c43fae39..1cd7b028c06 100644 --- a/gcc/config/avr/avr-log.c +++ b/gcc/config/avr/avr-log.c @@ -302,6 +302,7 @@ avr_log_set_avr_log (void) SET_DUMP_DETAIL (address_cost); SET_DUMP_DETAIL (builtin); SET_DUMP_DETAIL (constraints); + SET_DUMP_DETAIL (insn_addresses); SET_DUMP_DETAIL (legitimate_address_p); SET_DUMP_DETAIL (legitimize_address); SET_DUMP_DETAIL (legitimize_reload_address); diff --git a/gcc/config/avr/avr-protos.h b/gcc/config/avr/avr-protos.h index abe0575e17c..56e149832d5 100644 --- a/gcc/config/avr/avr-protos.h +++ b/gcc/config/avr/avr-protos.h @@ -87,7 +87,7 @@ extern bool avr_emit_movmemhi (rtx*); extern int avr_epilogue_uses (int regno); extern int avr_starting_frame_offset (void); -extern void avr_output_addr_vec_elt (FILE *stream, int value); +extern void avr_output_addr_vec (rtx_insn*, rtx); extern const char *avr_out_sbxx_branch (rtx_insn *insn, rtx operands[]); extern const char* avr_out_bitop (rtx, rtx*, int*); extern const char* avr_out_plus (rtx, rtx*, int* =NULL, int* =NULL, bool =true); @@ -175,6 +175,7 @@ typedef struct unsigned address_cost :1; unsigned builtin :1; unsigned constraints :1; + unsigned insn_addresses :1; unsigned legitimate_address_p :1; unsigned legitimize_address :1; unsigned legitimize_reload_address :1; diff --git a/gcc/config/avr/avr.c b/gcc/config/avr/avr.c index ba35b9e1542..734ede10d6f 100644 --- a/gcc/config/avr/avr.c +++ b/gcc/config/avr/avr.c @@ -3088,6 +3088,10 @@ avr_final_prescan_insn (rtx_insn *insn, rtx *operand ATTRIBUTE_UNUSED, rtx_cost (PATTERN (insn), VOIDmode, INSN, 0, optimize_insn_for_speed_p())); } + + if (avr_log.insn_addresses) + fprintf (asm_out_file, ";; ADDR = %d\n", + (int) INSN_ADDRESSES (INSN_UID (insn))); } /* Return 0 if undefined, 1 if always true or always false. */ @@ -9137,6 +9141,12 @@ avr_adjust_insn_length (rtx_insn *insn, int len) rtx *op = recog_data.operand; enum attr_adjust_len adjust_len; + /* As we pretend jump tables in .text, fix branch offsets crossing jump + tables now. */ + + if (JUMP_TABLE_DATA_P (insn)) + return 0; + /* Some complex insns don't need length adjustment and therefore the length need not/must not be adjusted for these insns. It is easier to state this in an insn attribute "adjust_len" than @@ -12312,17 +12322,88 @@ avr_out_reload_inpsi (rtx *op, rtx clobber_reg, int *len) } -/* Worker function for `ASM_OUTPUT_ADDR_VEC_ELT'. */ +/* Worker function for `ASM_OUTPUT_ADDR_VEC'. */ +/* Emit jump tables out-of-line so that branches crossing the table + get shorter offsets. If we have JUMP + CALL, then put the tables + in a dedicated non-.text section so that CALLs get better chance to + be relaxed to RCALLs. + + We emit the tables by hand because `function_rodata_section' does not + work as expected, cf. PR71151, and we do *NOT* want the table to be + in .rodata, hence setting JUMP_TABLES_IN_TEXT_SECTION = 0 is of limited + use; and setting it to 1 attributes table lengths to branch offsets... + Moreover, fincal.c keeps switching section before each table entry + which we find too fragile as to rely on section caching. */ void -avr_output_addr_vec_elt (FILE *stream, int value) +avr_output_addr_vec (rtx_insn *labl, rtx table) { - if (AVR_HAVE_JMP_CALL) - fprintf (stream, "\t.word gs(.L%d)\n", value); + FILE *stream = asm_out_file; + + app_disable(); + + // Switch to appropriate (sub)section. + + if (DECL_SECTION_NAME (current_function_decl) + && symtab_node::get (current_function_decl) + && ! symtab_node::get (current_function_decl)->implicit_section) + { + // .subsection will emit the code after the function and in the + // section as chosen by the user. + + switch_to_section (current_function_section ()); + fprintf (stream, "\t.subsection\t1\n"); + } else - fprintf (stream, "\trjmp .L%d\n", value); + { + // Since PR63223 there is no restriction where to put the table; it + // may even reside above 128 KiB. We put it in a section as high as + // possible and avoid progmem in order not to waste flash <= 64 KiB. + + const char *sec_name = ".jumptables.gcc"; + + // The table belongs to its host function, therefore use fine + // grained sections so that, if that function is removed by + // --gc-sections, the child table(s) may also be removed. */ + + tree asm_name = DECL_ASSEMBLER_NAME (current_function_decl); + const char *fname = IDENTIFIER_POINTER (asm_name); + fname = targetm.strip_name_encoding (fname); + sec_name = ACONCAT ((sec_name, ".", fname, NULL)); + + fprintf (stream, "\t.section\t%s,\"%s\",@progbits\n", sec_name, + AVR_HAVE_JMP_CALL ? "a" : "ax"); + } + + // Output the label that preceeds the table. + + ASM_OUTPUT_ALIGN (stream, 1); + targetm.asm_out.internal_label (stream, "L", CODE_LABEL_NUMBER (labl)); + + // Output the table's content. + + int vlen = XVECLEN (table, 0); + + for (int idx = 0; idx < vlen; idx++) + { + int value = CODE_LABEL_NUMBER (XEXP (XVECEXP (table, 0, idx), 0)); + + if (AVR_HAVE_JMP_CALL) + fprintf (stream, "\t.word gs(.L%d)\n", value); + else + fprintf (stream, "\trjmp .L%d\n", value); + } + + // Switch back to original section. As we clobbered the section above, + // forget the current section before switching back. + + in_section = NULL; + switch_to_section (current_function_section ()); } + +/* Implement `TARGET_CONDITIONAL_REGISTER_USAGE'. */ + static void avr_conditional_register_usage (void) { diff --git a/gcc/config/avr/avr.h b/gcc/config/avr/avr.h index 3158887fc01..d5fc345bbeb 100644 --- a/gcc/config/avr/avr.h +++ b/gcc/config/avr/avr.h @@ -398,6 +398,10 @@ typedef struct avr_args #define SUPPORTS_INIT_PRIORITY 0 +/* We pretend jump tables are in text section because otherwise, + final.c will switch to .rodata before jump tables and thereby + triggers __do_copy_data. As we implement ASM_OUTPUT_ADDR_VEC, + we still have full control over the jump tables themselves. */ #define JUMP_TABLES_IN_TEXT_SECTION 1 #define ASM_COMMENT_START " ; " @@ -447,8 +451,8 @@ typedef struct avr_args fprintf (STREAM, "\tpop\tr%d", REGNO); \ } -#define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE) \ - avr_output_addr_vec_elt (STREAM, VALUE) +#define ASM_OUTPUT_ADDR_VEC(TLABEL, TDATA) \ + avr_output_addr_vec (TLABEL, TDATA) #define ASM_OUTPUT_ALIGN(STREAM, POWER) \ do { \ diff --git a/gcc/config/avr/avr.md b/gcc/config/avr/avr.md index a9be9a406c3..2cdddb25cd0 100644 --- a/gcc/config/avr/avr.md +++ b/gcc/config/avr/avr.md @@ -5185,7 +5185,7 @@ (set_attr "cc" "none")]) ;; table jump -;; For entries in jump table see avr_output_addr_vec_elt. +;; For entries in jump table see avr_output_addr_vec. ;; Table made from ;; "rjmp .L" instructions for <= 8K devices diff --git a/gcc/config/avr/elf.h b/gcc/config/avr/elf.h index f6b18d2e814..e11c04e9d6d 100644 --- a/gcc/config/avr/elf.h +++ b/gcc/config/avr/elf.h @@ -31,11 +31,6 @@ #undef STRING_LIMIT #define STRING_LIMIT ((unsigned) 64) -/* Output alignment 2**1 for jump tables. */ -#undef ASM_OUTPUT_BEFORE_CASE_LABEL -#define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE, PREFIX, NUM, TABLE) \ - ASM_OUTPUT_ALIGN (FILE, 1); - /* Be conservative in crtstuff.c. */ #undef INIT_SECTION_ASM_OP #undef FINI_SECTION_ASM_OP -- 2.30.2