builtins.c (expand_builtin_setjmp_receiver): Use and clobber hard_frame_pointer_rtx.

gcc/
	* builtins.c (expand_builtin_setjmp_receiver): Use and clobber
	hard_frame_pointer_rtx.
	* cse.c (cse_insn): Remove volatile check.
	* cselib.c (cselib_process_insn): Likewise.
	* dse.c (scan_insn): Likewise.

From-SVN: r208498

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d1b7a502361697ef087387e30719a453d2af58dc..5993f2dd31647cd0640cc2480e565831b2bafdc1 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2014-03-11  Richard Sandiford  <rdsandiford@googlemail.com>
+
+       * builtins.c (expand_builtin_setjmp_receiver): Use and clobber
+       hard_frame_pointer_rtx.
+       * cse.c (cse_insn): Remove volatile check.
+       * cselib.c (cselib_process_insn): Likewise.
+       * dse.c (scan_insn): Likewise.
+
 2014-03-11  Joern Rennecke  <joern.rennecke@embecosm.com>
 
        * config/arc/arc.c (conditionalize_nonjump): New function, broken

diff --git a/gcc/builtins.c b/gcc/builtins.c
index 7c6318ee4aba09dfa12e301bd72278cd360c0fc1..e4846c8e6d7d337b7da45b63db7a23aff5f0ee5e 100644 (file)
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -910,18 +910,27 @@ expand_builtin_setjmp_receiver (rtx receiver_label ATTRIBUTE_UNUSED)
 #ifdef HAVE_nonlocal_goto
   if (! HAVE_nonlocal_goto)
 #endif
-    /* First adjust our frame pointer to its actual value.  It was
-       previously set to the start of the virtual area corresponding to
-       the stacked variables when we branched here and now needs to be
-       adjusted to the actual hardware fp value.
-
-       Assignments to virtual registers are converted by
-       instantiate_virtual_regs into the corresponding assignment
-       to the underlying register (fp in this case) that makes
-       the original assignment true.
-       So the following insn will actually be decrementing fp by
-       STARTING_FRAME_OFFSET.  */
-    emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx);
+    {
+      /* First adjust our frame pointer to its actual value.  It was
+        previously set to the start of the virtual area corresponding to
+        the stacked variables when we branched here and now needs to be
+        adjusted to the actual hardware fp value.
+
+        Assignments to virtual registers are converted by
+        instantiate_virtual_regs into the corresponding assignment
+        to the underlying register (fp in this case) that makes
+        the original assignment true.
+        So the following insn will actually be decrementing fp by
+        STARTING_FRAME_OFFSET.  */
+      emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx);
+
+      /* Restoring the frame pointer also modifies the hard frame pointer.
+        Mark it used (so that the previous assignment remains live once
+        the frame pointer is eliminated) and clobbered (to represent the
+        implicit update from the assignment).  */
+      emit_use (hard_frame_pointer_rtx);
+      emit_clobber (hard_frame_pointer_rtx);
+    }
 
 #if !HARD_FRAME_POINTER_IS_ARG_POINTER
   if (fixed_regs[ARG_POINTER_REGNUM])
@@ -965,8 +974,7 @@ expand_builtin_setjmp_receiver (rtx receiver_label ATTRIBUTE_UNUSED)
 
   /* We must not allow the code we just generated to be reordered by
      scheduling.  Specifically, the update of the frame pointer must
-     happen immediately, not later.  Similarly, we must block
-     (frame-related) register values to be used across this code.  */
+     happen immediately, not later.  */
   emit_insn (gen_blockage ());
 }
 

diff --git a/gcc/cse.c b/gcc/cse.c
index dba85f1891c9d701b62965d2b3c636e242583e7c..852d13ebf5bcdc13a1a7ad6fcb2759abba371c0c 100644 (file)
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -5682,11 +5682,6 @@ cse_insn (rtx insn)
          invalidate (XEXP (dest, 0), GET_MODE (dest));
       }
 
-  /* A volatile ASM or an UNSPEC_VOLATILE invalidates everything.  */
-  if (NONJUMP_INSN_P (insn)
-      && volatile_insn_p (PATTERN (insn)))
-    flush_hash_table ();
-
   /* Don't cse over a call to setjmp; on some machines (eg VAX)
      the regs restored by the longjmp come from a later time
      than the setjmp.  */

diff --git a/gcc/cselib.c b/gcc/cselib.c
index 4dfc55778b9236fe62581ef39b76264c30645cf4..26bcbe0776918a7116776ca36dd743bf7fec314d 100644 (file)
--- a/gcc/cselib.c
+++ b/gcc/cselib.c
@@ -2645,12 +2645,10 @@ cselib_process_insn (rtx insn)
 
   cselib_current_insn = insn;
 
-  /* Forget everything at a CODE_LABEL, a volatile insn, or a setjmp.  */
+  /* Forget everything at a CODE_LABEL or a setjmp.  */
   if ((LABEL_P (insn)
        || (CALL_P (insn)
-          && find_reg_note (insn, REG_SETJMP, NULL))
-       || (NONJUMP_INSN_P (insn)
-          && volatile_insn_p (PATTERN (insn))))
+          && find_reg_note (insn, REG_SETJMP, NULL)))
       && !cselib_preserve_constants)
     {
       cselib_reset_table (next_uid);

diff --git a/gcc/dse.c b/gcc/dse.c
index f5c9c7376ea5c968d9ac045049fe19e8c43a2436..09dc5df6e93e2eea0c5a9b4f285e23513baccbd0 100644 (file)
--- a/gcc/dse.c
+++ b/gcc/dse.c
@@ -2470,16 +2470,6 @@ scan_insn (bb_info_t bb_info, rtx insn)
       return;
     }
 
-  /* Cselib clears the table for this case, so we have to essentially
-     do the same.  */
-  if (NONJUMP_INSN_P (insn)
-      && volatile_insn_p (PATTERN (insn)))
-    {
-      add_wild_read (bb_info);
-      insn_info->cannot_delete = true;
-      return;
-    }
-
   /* Look at all of the uses in the insn.  */
   note_uses (&PATTERN (insn), check_mem_read_use, bb_info);