S/390: Implement -mrecord-mcount

This is the counterpart of the i386 feature introduced by
39a5a6a4: Add direct support for Linux kernel __fentry__ patching.

2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>

	* config/s390/s390.c (s390_function_profiler): Generate
	__mcount_loc section.
	* config/s390/s390.opt: Add the new option.

2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>

	* testsuite/gcc.target/s390/mrecord-mcount.c: New testcase.

From-SVN: r262733

gcc/ChangeLog

 2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>
 
+	* gcc/config/s390/s390.c (s390_function_profiler): Generate
+	__mcount_loc section.
+	* gcc/config/s390/s390.opt: Add the new option.
+
+2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>
+
 	* common.opt: Add the new warning.
 	* config/s390/s390.c (s390_function_profiler): Emit "brasl
 	%r0,__fentry__" when -mfentry is specified.

gcc/config/s390/s390.c

@@ -13151,6 +13151,9 @@ s390_function_profiler (FILE *file, int labelno)
       op[4] = gen_rtx_CONST (Pmode, op[4]);
     }
 
+  if (flag_record_mcount)
+    fprintf (file, "1:\n");
+
   if (flag_fentry)
     {
       if (cfun->static_chain_decl)
@@ -13204,6 +13207,13 @@ s390_function_profiler (FILE *file, int labelno)
       output_asm_insn ("basr\t%0,%0", op);
       output_asm_insn ("l\t%0,%1", op);
     }
+
+  if (flag_record_mcount)
+    {
+      fprintf (file, "\t.section __mcount_loc, \"a\",@progbits\n");
+      fprintf (file, "\t.%s 1b\n", TARGET_64BIT ? "quad" : "long");
+      fprintf (file, "\t.previous\n");
+    }
 }
 
 /* Encode symbol attributes (local vs. global, tls model) of a SYMBOL_REF

gcc/config/s390/s390.opt

@@ -298,3 +298,7 @@ mfentry
 Target Report Var(flag_fentry)
 Emit profiling counter call at function entry before prologue. The compiled
 code will require a 64-bit CPU and glibc 2.29 or newer to run.
+
+mrecord-mcount
+Target Report Var(flag_record_mcount)
+Generate __mcount_loc section with all _mcount and __fentry__ calls.

gcc/testsuite/ChangeLog

 2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>
 
+	* testsuite/gcc.target/s390/mrecord-mcount.c: New testcase.
+
+2018-07-16  Ilya Leoshkevich  <iii@linux.ibm.com>
+
 	* gcc.target/s390/mfentry-m64.c: New testcase.
 
 2018-07-16  Hristian Kirtchev  <kirtchev@adacore.com>

gcc/testsuite/gcc.target/s390/mrecord-mcount.c

+/* { dg-do compile } */
+/* { dg-options "-pg -mrecord-mcount" } */
+
+void
+profileme (void)
+{
+  /* { dg-final { scan-assembler ".section __mcount_loc, \"a\",@progbits" } } */
+  /* { dg-final { scan-assembler ".quad 1b" } } */
+  /* { dg-final { scan-assembler ".previous" } } */
+}