[committed][PATCH] Stack clash protection 03/08 - V4

[Jeff Law <law at redhat dot com>]

This patch just provides some generic logging facilities that will be
used by the backends to verify their behavior at a high level.  I don't
think it changed since V3.

This patch was bootstrapped and regression tested with the next patch
(x86 bits).  It was not bootstrapped and regression tested on its own.

Committing to the trunk.

Jeff

commit 02a09d2cdd5c3e1a6b3017587a28ee5d788705b7
Author: law <law@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Wed Sep 20 05:23:51 2017 +0000

            * function.c (dump_stack_clash_frame_info): New function.
            * function.h (dump_stack_clash_frame_info): Prototype.
            (enum stack_clash_probes): New enum.
    
    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@252997 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 070692c5053..97833130937 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,9 @@
 2017-09-19  Jeff Law  <law@redhat.com>
 
+        * function.c (dump_stack_clash_frame_info): New function.
+        * function.h (dump_stack_clash_frame_info): Prototype.
+        (enum stack_clash_probes): New enum.
+
 	* config/alpha/alpha.c (alpha_expand_prologue): Also check
 	flag_stack_clash_protection.
 	* config/arm/arm.c (arm_compute_static_chain_stack_bytes): Likewise.
diff --git a/gcc/function.c b/gcc/function.c
index 3ae5a3afc0b..c03e2ac5142 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -5681,6 +5681,58 @@ get_arg_pointer_save_area (void)
   return ret;
 }
 
+
+/* If debugging dumps are requested, dump information about how the
+   target handled -fstack-check=clash for the prologue.
+
+   PROBES describes what if any probes were emitted.
+
+   RESIDUALS indicates if the prologue had any residual allocation
+   (i.e. total allocation was not a multiple of PROBE_INTERVAL).  */
+
+void
+dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
+{
+  if (!dump_file)
+    return;
+
+  switch (probes)
+    {
+    case NO_PROBE_NO_FRAME:
+      fprintf (dump_file,
+	       "Stack clash no probe no stack adjustment in prologue.\n");
+      break;
+    case NO_PROBE_SMALL_FRAME:
+      fprintf (dump_file,
+	       "Stack clash no probe small stack adjustment in prologue.\n");
+      break;
+    case PROBE_INLINE:
+      fprintf (dump_file, "Stack clash inline probes in prologue.\n");
+      break;
+    case PROBE_LOOP:
+      fprintf (dump_file, "Stack clash probe loop in prologue.\n");
+      break;
+    }
+
+  if (residuals)
+    fprintf (dump_file, "Stack clash residual allocation in prologue.\n");
+  else
+    fprintf (dump_file, "Stack clash no residual allocation in prologue.\n");
+
+  if (frame_pointer_needed)
+    fprintf (dump_file, "Stack clash frame pointer needed.\n");
+  else
+    fprintf (dump_file, "Stack clash no frame pointer needed.\n");
+
+  if (TREE_THIS_VOLATILE (cfun->decl))
+    fprintf (dump_file,
+	     "Stack clash noreturn prologue, assuming no implicit"
+	     " probes in caller.\n");
+  else
+    fprintf (dump_file,
+	     "Stack clash not noreturn prologue.\n");
+}
+
 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
    for the first time.  */
 
diff --git a/gcc/function.h b/gcc/function.h
index 91e01383252..76434cd59a5 100644
--- a/gcc/function.h
+++ b/gcc/function.h
@@ -551,6 +551,14 @@ do {								\
   ((TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn)	     \
    ? MAX (FUNCTION_BOUNDARY, 2 * BITS_PER_UNIT) : FUNCTION_BOUNDARY)
 
+enum stack_clash_probes {
+  NO_PROBE_NO_FRAME,
+  NO_PROBE_SMALL_FRAME,
+  PROBE_INLINE,
+  PROBE_LOOP
+};
+
+extern void dump_stack_clash_frame_info (enum stack_clash_probes, bool);
 
 
 extern void push_function_context (void);