rs6000.c (rs6000_emit_prologue_move_from_cr): Rename from…

rs6000.c (rs6000_emit_prologue_move_from_cr): Rename from rs6000_emit_move_from_cr and call renamed function.

	* config/rs6000/rs6000.c (rs6000_emit_prologue_move_from_cr): Rename from
	rs6000_emit_move_from_cr and call renamed function.
	(rs6000_emit_prologue): Call renamed functions.
	* config/rs6000/rs6000.md (prologue_movesi_from_cr): Rename from
	movesi_from_cr, remove volatile CRs.

	* gcc.target/powerpc/cr_shrink-wrap.c: New.

From-SVN: r251543

gcc/ChangeLog

+2017-08-30  Pat Haugen  <pthaugen@us.ibm.com>
+
+	* config/rs6000/rs6000.c (rs6000_emit_prologue_move_from_cr): Rename from
+	rs6000_emit_move_from_cr and call renamed function.
+	(rs6000_emit_prologue): Call renamed functions.
+	* config/rs6000/rs6000.md (prologue_movesi_from_cr): Rename from
+	movesi_from_cr, remove volatile CRs.
+
 2017-08-30  Jon Beniston  <jon@beniston.com>
 	    Richard Biener  <rguenther@suse.de>
 

gcc/config/rs6000/rs6000.c

@@ -26097,10 +26097,14 @@ rs6000_emit_savres_rtx (rs6000_stack_t *info,
   return insn;
 }
 
-/* Emit code to store CR fields that need to be saved into REG.  */
+/* Emit prologue code to store CR fields that need to be saved into REG.  This
+   function should only be called when moving the non-volatile CRs to REG, it
+   is not a general purpose routine to move the entire set of CRs to REG.
+   Specifically, gen_prologue_movesi_from_cr() does not contain uses of the
+   volatile CRs.  */
 
 static void
-rs6000_emit_move_from_cr (rtx reg)
+rs6000_emit_prologue_move_from_cr (rtx reg)
 {
   /* Only the ELFv2 ABI allows storing only selected fields.  */
   if (DEFAULT_ABI == ABI_ELFv2 && TARGET_MFCRF)
@@ -26131,7 +26135,7 @@ rs6000_emit_move_from_cr (rtx reg)
 	 as well, using logical operations to combine the values.  */
     }
 
-  emit_insn (gen_movesi_from_cr (reg));
+  emit_insn (gen_prologue_movesi_from_cr (reg));
 }
 
 /* Return whether the split-stack arg pointer (r12) is used.  */
@@ -26871,7 +26875,7 @@ rs6000_emit_prologue (void)
     {
       cr_save_rtx = gen_rtx_REG (SImode, cr_save_regno);
       START_USE (cr_save_regno);
-      rs6000_emit_move_from_cr (cr_save_rtx);
+      rs6000_emit_prologue_move_from_cr (cr_save_rtx);
     }
 
   /* Do any required saving of fpr's.  If only one or two to save, do
@@ -27109,7 +27113,7 @@ rs6000_emit_prologue (void)
 	{
 	  START_USE (0);
 	  cr_save_rtx = gen_rtx_REG (SImode, 0);
-	  rs6000_emit_move_from_cr (cr_save_rtx);
+	  rs6000_emit_prologue_move_from_cr (cr_save_rtx);
 	}
 
       /* Saving CR requires a two-instruction sequence: one instruction
@@ -27196,7 +27200,7 @@ rs6000_emit_prologue (void)
       /* ??? We might get better performance by using multiple mfocrf
 	 instructions.  */
       crsave = gen_rtx_REG (SImode, 0);
-      emit_insn (gen_movesi_from_cr (crsave));
+      emit_insn (gen_prologue_movesi_from_cr (crsave));
 
       for (i = 0; i < 8; i++)
 	if (!call_used_regs[CR0_REGNO + i])

gcc/config/rs6000/rs6000.md

@@ -13032,12 +13032,14 @@
 }"
   [(set_attr "type" "mfcrf")])
 
-(define_insn "movesi_from_cr"
+;; Don't include the volatile CRs since their values are not used wrt CR save
+;; in the prologue and doing so prevents shrink-wrapping because we can't move the
+;; prologue past an insn (early exit test) that defines a register used in the
+;; prologue.
+(define_insn "prologue_movesi_from_cr"
   [(set (match_operand:SI 0 "gpc_reg_operand" "=r")
-        (unspec:SI [(reg:CC CR0_REGNO) (reg:CC CR1_REGNO)
-		    (reg:CC CR2_REGNO) (reg:CC CR3_REGNO)
-		    (reg:CC CR4_REGNO) (reg:CC CR5_REGNO)
-		    (reg:CC CR6_REGNO) (reg:CC CR7_REGNO)]
+        (unspec:SI [(reg:CC CR2_REGNO) (reg:CC CR3_REGNO)
+		    (reg:CC CR4_REGNO)]
 		   UNSPEC_MOVESI_FROM_CR))]
   ""
   "mfcr %0"

gcc/testsuite/ChangeLog

+2017-08-30  Pat Haugen  <pthaugen@us.ibm.com>
+
+	* gcc.target/powerpc/cr_shrink-wrap.c: New.
+
 2017-08-30  Michael Meissner  <meissner@linux.vnet.ibm.com>
 
 	PR target/82015

gcc/testsuite/gcc.target/powerpc/cr_shrink-wrap.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-rtl-pro_and_epilogue" } */
+
+void foo(int i)
+{
+  if (i > 0)
+    /* Non-volatile CR kill on true path should not prevent shrink-wrap.  */
+    asm ("" : : : "cr2", "cr3");
+}
+
+/* { dg-final { scan-rtl-dump-times "Performing shrink-wrapping" 1 "pro_and_epilogue" } } */