[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.

1 files changed, 57 insertions, 0 deletions

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)
 {