S/390: Fix cfi for GPR 2 FPR saves

gcc/ChangeLog:

2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	    * config/s390/s390.c (s390_save_gprs_to_fprs): Add CFA_REGISTER
	    reg note to the GPR -> FPR save instructions.

gcc/testsuite/ChangeLog:

2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	    * gcc.target/s390/gpr2fprsavecfi.c: New test.

From-SVN: r226149

gcc/ChangeLog

 2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
+	* config/s390/s390.c (s390_save_gprs_to_fprs): Add CFA_REGISTER
+	reg note to the GPR -> FPR save instructions.
+
+2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
 	* config/s390/s390.c (s390_rtx_costs): Make risbg patterns
 	cheaper.
 	(s390_expand_insv): Don't generate risbg pattern for constant zero

gcc/config/s390/s390.c

@@ -10132,6 +10132,10 @@ s390_save_gprs_to_fprs (void)
 	    emit_move_insn (gen_rtx_REG (DImode, cfun_gpr_save_slot (i)),
 			    gen_rtx_REG (DImode, i));
 	  RTX_FRAME_RELATED_P (insn) = 1;
+	  /* This prevents dwarf2cfi from interpreting the set.  Doing
+	     so it might emit def_cfa_register infos setting an FPR as
+	     new CFA.  */
+	  add_reg_note (insn, REG_CFA_REGISTER, PATTERN (insn));
 	}
     }
 }

gcc/testsuite/ChangeLog

 2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
+	* gcc.target/s390/gpr2fprsavecfi.c: New test.
+
+2015-07-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
 	* gcc.target/s390/insv-1.c: New test.
 	* gcc.target/s390/insv-2.c: New test.
 	* gcc.target/s390/insv-3.c: New test.

gcc/testsuite/gcc.target/s390/gpr2fprsavecfi.c

+/* { dg-do compile } */
+/* { dg-options "-O3 -march=z10 -mzarch -fdwarf2-cfi-asm" } */
+
+char *gl[100];
+
+long
+foo ()
+{
+  long r = 0;
+  char bla[100];
+  int i;
+
+  __builtin_memcpy (bla, gl, 100);
+
+  for (i = 0; i < 100; i++)
+    r += bla[i];
+
+  return r;
+}
+
+/* { dg-final { scan-assembler-not "cfi_def_cfa_register" } } */
+/* { dg-final { scan-assembler "cfi_register" } } */
+/* { dg-final { scan-assembler "cfi_def_cfa_offset" } } */