From e3b3b59683c1e7d31a9d313dd97394abebf644be Mon Sep 17 00:00:00 2001 From: "Vladimir N. Makarov" Date: Fri, 13 Nov 2020 12:45:59 -0500 Subject: [PATCH] Implementation of asm goto outputs gcc/ * cfgexpand.c (expand_asm_stmt): Output asm goto with outputs too. Place insns after asm goto on edges. * doc/extend.texi: Reflect the changes in asm goto documentation. * gimple.c (gimple_build_asm_1): Remove an assert checking output absence for asm goto. * gimple.h (gimple_asm_label_op, gimple_asm_set_label_op): Take possible asm goto outputs into account. * ira.c (ira): Remove critical edges for potential asm goto output reloads. (ira_nullify_asm_goto): New function. * ira.h (ira_nullify_asm_goto): New prototype. * lra-assigns.c (lra_split_hard_reg_for): Use ira_nullify_asm_goto. Check that splitting is done inside a basic block. * lra-constraints.c (curr_insn_transform): Permit output reloads for any jump insn. * lra-spills.c (lra_final_code_change): Remove USEs added in ira for asm gotos. * lra.c (lra_process_new_insns): Place output reload insns after jumps in the beginning of destination BBs. * reload.c (find_reloads): Report error for asm gotos with outputs. Modify them to keep CFG consistency to avoid crashes. * tree-into-ssa.c (rewrite_stmt): Don't put debug stmt after asm goto. gcc/c/ * c-parser.c (c_parser_asm_statement): Parse outputs for asm goto too. * c-typeck.c (build_asm_expr): Remove an assert checking output absence for asm goto. gcc/cp * parser.c (cp_parser_asm_definition): Parse outputs for asm goto too. gcc/testsuite/ * c-c++-common/asmgoto-2.c: Permit output in asm goto. * gcc.c-torture/compile/asmgoto-2.c: New. * gcc.c-torture/compile/asmgoto-3.c: New. * gcc.c-torture/compile/asmgoto-4.c: New. * gcc.c-torture/compile/asmgoto-5.c: New. --- gcc/ira.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) (limited to 'gcc/ira.c') diff --git a/gcc/ira.c b/gcc/ira.c index 5443031..3c824e9 100644 --- a/gcc/ira.c +++ b/gcc/ira.c @@ -5401,6 +5401,48 @@ ira (FILE *f) int ira_max_point_before_emit; bool saved_flag_caller_saves = flag_caller_saves; enum ira_region saved_flag_ira_region = flag_ira_region; + basic_block bb; + edge_iterator ei; + edge e; + bool output_jump_reload_p = false; + + if (ira_use_lra_p) + { + /* First put potential jump output reloads on the output edges + as USE which will be removed at the end of LRA. The major + goal is actually to create BBs for critical edges for LRA and + populate them later by live info. In LRA it will be + difficult to do this. */ + FOR_EACH_BB_FN (bb, cfun) + { + rtx_insn *end = BB_END (bb); + if (!JUMP_P (end)) + continue; + extract_insn (end); + for (int i = 0; i < recog_data.n_operands; i++) + if (recog_data.operand_type[i] != OP_IN) + { + output_jump_reload_p = true; + FOR_EACH_EDGE (e, ei, bb->succs) + if (EDGE_CRITICAL_P (e) + && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) + { + ira_assert (!(e->flags & EDGE_ABNORMAL)); + start_sequence (); + /* We need to put some no-op insn here. We can + not put a note as commit_edges insertion will + fail. */ + emit_insn (gen_rtx_USE (VOIDmode, const1_rtx)); + rtx_insn *insns = get_insns (); + end_sequence (); + insert_insn_on_edge (insns, e); + } + break; + } + } + if (output_jump_reload_p) + commit_edge_insertions (); + } if (flag_ira_verbose < 10) { @@ -5709,6 +5751,21 @@ ira (FILE *f) } } +/* Modify asm goto to avoid further trouble with this insn. We can + not replace the insn by USE as in other asm insns as we still + need to keep CFG consistency. */ +void +ira_nullify_asm_goto (rtx_insn *insn) +{ + ira_assert (JUMP_P (insn) && INSN_CODE (insn) < 0); + rtx tmp = extract_asm_operands (PATTERN (insn)); + PATTERN (insn) = gen_rtx_ASM_OPERANDS (VOIDmode, ggc_strdup (""), "", 0, + rtvec_alloc (0), + rtvec_alloc (0), + ASM_OPERANDS_LABEL_VEC (tmp), + ASM_OPERANDS_SOURCE_LOCATION(tmp)); +} + static void do_reload (void) { -- cgit v1.1