PR rtl-optimization/52773

	* calls.c (emit_library_call_value): When pushing arguments use
	stack_pointer_rtx rather than virtual_outgoing_args_rtx in
	CALL_INSN_FUNCTION_USAGE.  Only emit one of use of the magic
	stack pointer reference into CALL_INSN_FUNCTION_USAGE.

	PR rtl-optimization/52773
	* gcc.c-torture/compile/pr52773.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@219796 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 15 insertions, 7 deletions

diff --git a/gcc/calls.c b/gcc/calls.c
index 1c2f0adfa23..ec44624d7c9 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -3808,6 +3808,7 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
   int reg_parm_stack_space = 0;
   int needed;
   rtx_insn *before_call;
+  bool have_push_fusage;
   tree tfom;			/* type_for_mode (outmode, 0) */
 
 #ifdef REG_PARM_STACK_SPACE
@@ -4165,6 +4166,8 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
 
   /* Push the args that need to be pushed.  */
 
+  have_push_fusage = false;
+
   /* ARGNUM indexes the ARGVEC array in the order in which the arguments
      are to be pushed.  */
   for (count = 0; count < nargs; count++, argnum--)
@@ -4256,14 +4259,19 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
 	  if (argblock)
 	    use = plus_constant (Pmode, argblock,
 				 argvec[argnum].locate.offset.constant);
+	  else if (have_push_fusage)
+	    continue;
 	  else
-	    /* When arguments are pushed, trying to tell alias.c where
-	       exactly this argument is won't work, because the
-	       auto-increment causes confusion.  So we merely indicate
-	       that we access something with a known mode somewhere on
-	       the stack.  */
-	    use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
-				gen_rtx_SCRATCH (Pmode));
+	    {
+	      /* When arguments are pushed, trying to tell alias.c where
+		 exactly this argument is won't work, because the
+		 auto-increment causes confusion.  So we merely indicate
+		 that we access something with a known mode somewhere on
+		 the stack.  */
+	      use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
+				  gen_rtx_SCRATCH (Pmode));
+	      have_push_fusage = true;
+	    }
 	  use = gen_rtx_MEM (argvec[argnum].mode, use);
 	  use = gen_rtx_USE (VOIDmode, use);
 	  call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);