[PATCH] Add -fchecking

[Richard Biener <rguenther at suse dot de>]

This adds -fchecking as a way to enable internal consistency checks
even in release builds (or disable checking with -fno-checking - up to
a certain extent - with checking enabled).

Bootstrap & regtest running on x86_64-unknown-linux-gnu.

Richard.

2015-10-27  Richard Biener  <rguenther@suse.de>

	* common.opt (fchecking): New flag controlling flag_checking.
	* passes.c (execute_function_todo): Guard checking code with
	flag_checking instead of ENABLE_CHECKING.
	(execute_todo): Likewise.
	(execute_one_pass): Likewise.
	(verify_curr_properties): Always compile.
	* timevar.c: Include options.h.
	(timer::print): Adjust output.
	* doc/invoke.texi (fchecking): Document.

Index: gcc/common.opt
===================================================================
*** gcc/common.opt	(revision 229404)
--- gcc/common.opt	(working copy)
*************** int optimize_fast
*** 46,56 ****
  Variable
  bool in_lto_p = false
  
- ; Enable additional checks of internal state consistency, which may slow
- ; the compiler down.
- Variable
- bool flag_checking = CHECKING_P
- 
  ; 0 means straightforward implementation of complex divide acceptable.
  ; 1 means wide ranges of inputs must work for complex divide.
  ; 2 means C99-like requirements for complex multiply and divide.
--- 46,51 ----
*************** fcheck-new
*** 1002,1007 ****
--- 997,1006 ----
  Common Var(flag_check_new)
  Check the return value of new in C++.
  
+ fchecking
+ Common Var(flag_checking) Init(CHECKING_P)
+ Perform internal consistency checkings.
+ 
  fcombine-stack-adjustments
  Common Report Var(flag_combine_stack_adjustments) Optimization
  Looks for opportunities to reduce stack adjustments and stack references.
Index: gcc/passes.c
===================================================================
*** gcc/passes.c	(revision 229404)
--- gcc/passes.c	(working copy)
*************** execute_function_todo (function *fn, voi
*** 1952,1960 ****
  
    gcc_assert (dom_info_state (fn, CDI_POST_DOMINATORS) == DOM_NONE);
    /* If we've seen errors do not bother running any verifiers.  */
!   if (!seen_error ())
      {
- #if defined ENABLE_CHECKING
        dom_state pre_verify_state = dom_info_state (fn, CDI_DOMINATORS);
        dom_state pre_verify_pstate = dom_info_state (fn, CDI_POST_DOMINATORS);
  
--- 1952,1960 ----
  
    gcc_assert (dom_info_state (fn, CDI_POST_DOMINATORS) == DOM_NONE);
    /* If we've seen errors do not bother running any verifiers.  */
!   if (!seen_error ()
!       && flag_checking)
      {
        dom_state pre_verify_state = dom_info_state (fn, CDI_DOMINATORS);
        dom_state pre_verify_pstate = dom_info_state (fn, CDI_POST_DOMINATORS);
  
*************** execute_function_todo (function *fn, voi
*** 1988,1994 ****
        /* Make sure verifiers don't change dominator state.  */
        gcc_assert (dom_info_state (fn, CDI_DOMINATORS) == pre_verify_state);
        gcc_assert (dom_info_state (fn, CDI_POST_DOMINATORS) == pre_verify_pstate);
- #endif
      }
  
    fn->last_verified = flags & TODO_verify_all;
--- 1991,1996 ----
*************** execute_function_todo (function *fn, voi
*** 2008,2018 ****
  static void
  execute_todo (unsigned int flags)
  {
! #if defined ENABLE_CHECKING
!   if (cfun
        && need_ssa_update_p (cfun))
      gcc_assert (flags & TODO_update_ssa_any);
- #endif
  
    timevar_push (TV_TODO);
  
--- 2010,2019 ----
  static void
  execute_todo (unsigned int flags)
  {
!   if (flag_checking
!       && cfun
        && need_ssa_update_p (cfun))
      gcc_assert (flags & TODO_update_ssa_any);
  
    timevar_push (TV_TODO);
  
*************** clear_last_verified (function *fn, void
*** 2076,2089 ****
  /* Helper function. Verify that the properties has been turn into the
     properties expected by the pass.  */
  
- #ifdef ENABLE_CHECKING
  static void
  verify_curr_properties (function *fn, void *data)
  {
    unsigned int props = (size_t)data;
    gcc_assert ((fn->curr_properties & props) == props);
  }
- #endif
  
  /* Initialize pass dump file.  */
  /* This is non-static so that the plugins can use it.  */
--- 2077,2088 ----
*************** execute_one_pass (opt_pass *pass)
*** 2331,2344 ****
    /* Run pre-pass verification.  */
    execute_todo (pass->todo_flags_start);
  
! #ifdef ENABLE_CHECKING
!   do_per_function (verify_curr_properties,
! 		   (void *)(size_t)pass->properties_required);
! #endif
  
    /* If a timevar is present, start it.  */
    if (pass->tv_id != TV_NONE)
!     timevar_push (pass->tv_id);
  
    /* Do it!  */
    todo_after = pass->execute (cfun);
--- 2330,2342 ----
    /* Run pre-pass verification.  */
    execute_todo (pass->todo_flags_start);
  
!   if (flag_checking)
!     do_per_function (verify_curr_properties,
! 		     (void *)(size_t)pass->properties_required);
  
    /* If a timevar is present, start it.  */
    if (pass->tv_id != TV_NONE)
!     timevar_push (pass->tv_id);
  
    /* Do it!  */
    todo_after = pass->execute (cfun);

Index: gcc/doc/invoke.texi
===================================================================
*** gcc/doc/invoke.texi	(revision 229404)
--- gcc/doc/invoke.texi	(working copy)
*************** Objective-C and Objective-C++ Dialects}.
*** 310,316 ****
  -fsanitize=@var{style} -fsanitize-recover -fsanitize-recover=@var{style} @gol
  -fasan-shadow-offset=@var{number} -fsanitize-sections=@var{s1},@var{s2},... @gol
  -fsanitize-undefined-trap-on-error @gol
! -fcheck-pointer-bounds -fchkp-check-incomplete-type @gol
  -fchkp-first-field-has-own-bounds -fchkp-narrow-bounds @gol
  -fchkp-narrow-to-innermost-array -fchkp-optimize @gol
  -fchkp-use-fast-string-functions -fchkp-use-nochk-string-functions @gol
--- 310,316 ----
  -fsanitize=@var{style} -fsanitize-recover -fsanitize-recover=@var{style} @gol
  -fasan-shadow-offset=@var{number} -fsanitize-sections=@var{s1},@var{s2},... @gol
  -fsanitize-undefined-trap-on-error @gol
! -fcheck-pointer-bounds -fchecking -fchkp-check-incomplete-type @gol
  -fchkp-first-field-has-own-bounds -fchkp-narrow-bounds @gol
  -fchkp-narrow-to-innermost-array -fchkp-optimize @gol
  -fchkp-use-fast-string-functions -fchkp-use-nochk-string-functions @gol
*************** structure field attribute (@pxref{Type A
*** 6145,6150 ****
--- 6145,6156 ----
  functions for controlling the Pointer Bounds Checker.  @xref{Pointer
  Bounds Checker builtins}, for more information.
  
+ @item -fchecking
+ @opindex fchecking
+ @opindex fno-checking
+ Enable internal consistency checking.  The default depends on
+ the compiler configuration.
+ 
  @item -fchkp-check-incomplete-type
  @opindex fchkp-check-incomplete-type
  @opindex fno-chkp-check-incomplete-type
Index: gcc/timevar.c
===================================================================
*** gcc/timevar.c	(revision 229404)
--- gcc/timevar.c	(working copy)
*************** along with GCC; see the file COPYING3.
*** 22,27 ****
--- 22,28 ----
  #include "system.h"
  #include "coretypes.h"
  #include "timevar.h"
+ #include "options.h"
  
  #ifndef HAVE_CLOCK_T
  typedef int clock_t;
*************** timer::print (FILE *fp)
*** 727,736 ****
  #endif
    fprintf (fp, "%8u kB\n", (unsigned) (total->ggc_mem >> 10));
  
! #ifdef ENABLE_CHECKING
!   fprintf (fp, "Extra diagnostic checks enabled; compiler may run slowly.\n");
!   fprintf (fp, "Configure with --enable-checking=release to disable checks.\n");
! #endif
  #ifndef ENABLE_ASSERT_CHECKING
    fprintf (fp, "Internal checks disabled; compiler is not suited for release.\n");
    fprintf (fp, "Configure with --enable-checking=release to enable checks.\n");
--- 728,737 ----
  #endif
    fprintf (fp, "%8u kB\n", (unsigned) (total->ggc_mem >> 10));
  
!   if (CHECKING_P || flag_checking)
!     fprintf (fp, "Extra diagnostic checks enabled; compiler may run slowly.\n");
!   if (CHECKING_P)
!     fprintf (fp, "Configure with --enable-checking=release to disable checks.\n");
  #ifndef ENABLE_ASSERT_CHECKING
    fprintf (fp, "Internal checks disabled; compiler is not suited for release.\n");
    fprintf (fp, "Configure with --enable-checking=release to enable checks.\n");