re PR target/63354 (gcc -pg -mprofile-kernel creates unused stack frames on leaf…

re PR target/63354 (gcc -pg -mprofile-kernel creates unused stack frames on leaf functions on ppc64le)

[gcc]

2016-01-21  Anton Blanchard  <anton@samba.org>
	    Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR target/63354
	* config/rs6000/linux64.h (TARGET_KEEP_LEAF_WHEN_PROFILED): New
	#define.
	* config/rs6000/rs6000.c (rs6000_keep_leaf_when_profiled): New
	function.

[gcc/testsuite]

2016-01-21  Anton Blanchard  <anton@samba.org>
	    Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR target/63354
	* gcc.target/powerpc/pr63354.c:  New test.


Co-Authored-By: Bill Schmidt <wschmidt@linux.vnet.ibm.com>

From-SVN: r232684

gcc/ChangeLog

+2016-01-21  Anton Blanchard  <anton@samba.org>
+	    Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+	PR target/63354
+	* config/rs6000/linux64.h (TARGET_KEEP_LEAF_WHEN_PROFILED): New
+	#define.
+	* config/rs6000/rs6000.c (rs6000_keep_leaf_when_profiled): New
+	function.
+
 2016-01-21  Ajit Agarwal  <ajitkum@xilinx.com>
 
 	* config/microblaze/microblaze.c

gcc/config/rs6000/linux64.h

@@ -59,6 +59,9 @@ extern int dot_symbols;
 
 #define TARGET_PROFILE_KERNEL profile_kernel
 
+#undef TARGET_KEEP_LEAF_WHEN_PROFILED
+#define TARGET_KEEP_LEAF_WHEN_PROFILED rs6000_keep_leaf_when_profiled
+
 #define TARGET_USES_LINUX64_OPT 1
 #ifdef HAVE_LD_LARGE_TOC
 #undef TARGET_CMODEL

gcc/config/rs6000/rs6000.c

@@ -26237,6 +26237,14 @@ rs6000_output_function_prologue (FILE *file,
   rs6000_pic_labelno++;
 }
 
+/* -mprofile-kernel code calls mcount before the function prolog,
+   so a profiled leaf function should stay a leaf function.  */
+static bool
+rs6000_keep_leaf_when_profiled ()
+{
+  return TARGET_PROFILE_KERNEL;
+}
+
 /* Non-zero if vmx regs are restored before the frame pop, zero if
    we restore after the pop when possible.  */
 #define ALWAYS_RESTORE_ALTIVEC_BEFORE_POP 0

gcc/testsuite/ChangeLog

+2016-01-21  Anton Blanchard  <anton@samba.org>
+	    Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+	PR target/63354
+	* gcc.target/powerpc/pr63354.c:  New test.
+
 2016-01-21  Vladimir Makarov  <vmakarov@redhat.com>
 
 	PR rtl-optimization/68990

gcc/testsuite/gcc.target/powerpc/pr63354.c

+/* Verify that we don't stack a frame for leaf functions when using
+   -pg -mprofile-kernel.  */
+
+/* { dg-do compile { target { powerpc64*-*-* } } } */
+/* { dg-options "-O2 -pg -mprofile-kernel" } */
+/* { dg-final { scan-assembler-not "mtlr" } } */
+
+int foo(void)
+{
+  return 1;
+}