Merge dataflow branch into mainline

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@125624 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 111 insertions, 17 deletions

diff --git a/gcc/function.c b/gcc/function.c
index 7d2063c3a22..10fe7febe6c 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -63,6 +63,8 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 #include "tree-gimple.h"
 #include "tree-pass.h"
 #include "predict.h"
+#include "df.h"
+#include "timevar.h"
 #include "vecprim.h"
 
 #ifndef LOCAL_ALIGNMENT
@@ -100,7 +102,7 @@ int current_function_is_leaf;
 
 /* Nonzero if function being compiled doesn't modify the stack pointer
    (ignoring the prologue and epilogue).  This is only valid after
-   life_analysis has run.  */
+   pass_stack_ptr_mod has run.  */
 int current_function_sp_is_unchanging;
 
 /* Nonzero if the function being compiled is a leaf function which only
@@ -3485,13 +3487,32 @@ pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree siz
     }
 }
 
-/* Walk the tree of blocks describing the binding levels within a function
-   and warn about variables the might be killed by setjmp or vfork.
-   This is done after calling flow_analysis and before global_alloc
-   clobbers the pseudo-regs to hard regs.  */
 
-void
-setjmp_vars_warning (tree block)
+/* True if register REGNO was alive at a place where `setjmp' was
+   called and was set more than once or is an argument.  Such regs may
+   be clobbered by `longjmp'.  */
+
+static bool
+regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
+{
+  /* There appear to be cases where some local vars never reach the
+     backend but have bogus regnos.  */
+  if (regno >= max_reg_num ())
+    return false;
+
+  return ((REG_N_SETS (regno) > 1
+	   || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
+	  && REGNO_REG_SET_P (setjmp_crosses, regno));
+}
+
+/* Walk the tree of blocks describing the binding levels within a
+   function and warn about variables the might be killed by setjmp or
+   vfork.  This is done after calling flow_analysis before register
+   allocation since that will clobber the pseudo-regs to hard
+   regs.  */
+
+static void
+setjmp_vars_warning (bitmap setjmp_crosses, tree block)
 {
   tree decl, sub;
 
@@ -3500,32 +3521,47 @@ setjmp_vars_warning (tree block)
       if (TREE_CODE (decl) == VAR_DECL
 	  && DECL_RTL_SET_P (decl)
 	  && REG_P (DECL_RTL (decl))
-	  && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
+	  && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
 	warning (OPT_Wclobbered, "variable %q+D might be clobbered by" 
                  " %<longjmp%> or %<vfork%>", decl);
     }
 
   for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
-    setjmp_vars_warning (sub);
+    setjmp_vars_warning (setjmp_crosses, sub);
 }
 
 /* Do the appropriate part of setjmp_vars_warning
    but for arguments instead of local variables.  */
 
-void
-setjmp_args_warning (void)
+static void
+setjmp_args_warning (bitmap setjmp_crosses)
 {
   tree decl;
   for (decl = DECL_ARGUMENTS (current_function_decl);
        decl; decl = TREE_CHAIN (decl))
     if (DECL_RTL (decl) != 0
 	&& REG_P (DECL_RTL (decl))
-	&& regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
+	&& regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
       warning (OPT_Wclobbered, 
                "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
 	       decl);
 }
 
+/* Generate warning messages for variables live across setjmp.  */
+
+void 
+generate_setjmp_warnings (void)
+{
+  bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
+
+  if (n_basic_blocks == NUM_FIXED_BLOCKS
+      || bitmap_empty_p (setjmp_crosses))
+    return;
+
+  setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
+  setjmp_args_warning (setjmp_crosses);
+}
+
 
 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
    and create duplicate blocks.  */
@@ -4328,6 +4364,14 @@ expand_function_end (void)
       if (flag_exceptions)
 	sjlj_emit_function_exit_after (get_last_insn ());
     }
+  else
+    {
+      /* We want to ensure that instructions that may trap are not
+	 moved into the epilogue by scheduling, because we don't
+	 always emit unwind information for the epilogue.  */
+      if (flag_non_call_exceptions)
+	emit_insn (gen_blockage ());
+    }
 
   /* If this is an implementation of throw, do what's necessary to
      communicate between __builtin_eh_return and the epilogue.  */
@@ -4782,7 +4826,7 @@ keep_stack_depressed (rtx insns)
 		    && !fixed_regs[regno]
 		    && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
 		    && !REGNO_REG_SET_P
-		         (EXIT_BLOCK_PTR->il.rtl->global_live_at_start, regno)
+		    (DF_LR_IN (EXIT_BLOCK_PTR), regno)
 		    && !refers_to_regno_p (regno,
 					   end_hard_regno (Pmode, regno),
 					   info.equiv_reg_src, NULL)
@@ -4993,8 +5037,8 @@ emit_equiv_load (struct epi_info *p)
    this into place with notes indicating where the prologue ends and where
    the epilogue begins.  Update the basic block information when possible.  */
 
-void
-thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
+static void
+thread_prologue_and_epilogue_insns (void)
 {
   int inserted = 0;
   edge e;
@@ -5016,6 +5060,11 @@ thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
       seq = gen_prologue ();
       emit_insn (seq);
 
+      /* Insert an explicit USE for the frame pointer 
+         if the profiling is on and the frame pointer is required.  */
+      if (current_function_profile && frame_pointer_needed)
+        emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx));
+
       /* Retain a map of the prologue insns.  */
       record_insns (seq, &prologue);
       prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
@@ -5254,13 +5303,18 @@ epilogue_done:
 	}
     }
 #endif
+
+  /* Threading the prologue and epilogue changes the artificial refs
+     in the entry and exit blocks.  */
+  epilogue_completed = 1;
+  df_update_entry_exit_and_calls ();
 }
 
 /* Reposition the prologue-end and epilogue-begin notes after instruction
    scheduling and delayed branch scheduling.  */
 
 void
-reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
+reposition_prologue_and_epilogue_notes (void)
 {
 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
   rtx insn, last, note;
@@ -5273,7 +5327,7 @@ reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
       /* Scan from the beginning until we reach the last prologue insn.
 	 We apparently can't depend on basic_block_{head,end} after
 	 reorg has run.  */
-      for (insn = f; insn; insn = NEXT_INSN (insn))
+      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
 	{
 	  if (NOTE_P (insn))
 	    {
@@ -5354,6 +5408,13 @@ current_function_name (void)
 {
   return lang_hooks.decl_printable_name (cfun->decl, 2);
 }
+
+/* Returns the raw (mangled) name of the current function.  */
+const char *
+current_function_assembler_name (void)
+{
+  return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun->decl));
+}
 
 
 static unsigned int
@@ -5411,5 +5472,38 @@ struct tree_opt_pass pass_leaf_regs =
   0                                     /* letter */
 };
 
+static unsigned int
+rest_of_handle_thread_prologue_and_epilogue (void)
+{
+  if (optimize)
+    cleanup_cfg (CLEANUP_EXPENSIVE);
+  /* On some machines, the prologue and epilogue code, or parts thereof,
+     can be represented as RTL.  Doing so lets us schedule insns between
+     it and the rest of the code and also allows delayed branch
+     scheduling to operate in the epilogue.  */
+
+  thread_prologue_and_epilogue_insns ();
+  return 0;
+}
+
+struct tree_opt_pass pass_thread_prologue_and_epilogue =
+{
+  "pro_and_epilogue",                   /* name */
+  NULL,                                 /* gate */
+  rest_of_handle_thread_prologue_and_epilogue, /* execute */
+  NULL,                                 /* sub */
+  NULL,                                 /* next */
+  0,                                    /* static_pass_number */
+  TV_THREAD_PROLOGUE_AND_EPILOGUE,      /* tv_id */
+  0,                                    /* properties_required */
+  0,                                    /* properties_provided */
+  0,                                    /* properties_destroyed */
+  TODO_verify_flow,                     /* todo_flags_start */
+  TODO_dump_func |
+  TODO_df_finish |
+  TODO_ggc_collect,                     /* todo_flags_finish */
+  'w'                                   /* letter */
+};
+
 
 #include "gt-function.h"