common.opt (fcompare-debug=, [...]): New.

gcc/ChangeLog:
* common.opt (fcompare-debug=, fcompare-debug-second): New.
(fdump-final-insns=, gtoggle): New.
* doc/invoke.texi: Document them.
* final.c (rest_of_clean_state): Dump final insn stream.
* gcc.c (invoke_as): Hook in -fcompare-debug.
(static_spec_functions): Add compare-debug-dump-opt,
compare-debug-self-opt and compare-debug-auxbase-opt.
(compare_debug, compare_debug_second, compare_debug_opt): New.
(switches_debug_check, n_switches_debug_check): New.
(debug_auxbase_opt, debug_check_temp_file): New.
(process_command): Handle -fno-compare-debug, -fcompare-debug and
-fcompare-debug=*.
(do_self_spec): Handle arguments after switches.
(do_spec_1): Add .gk extension to temp file basenames for compare.
(check_live_switch): Take SWITCH_IGNORE into account, and earlier.
(cc1_options): Use it instead of normal auxbase computation for
the second compare-debug compilation.
(compare_files): New.
(main): Set up and implement compare debug mode.
(compare_debug_dump_opt_spec_function): New.
(compare_debug_self_opt_spec_function): New.
(compare_debug_auxbase_opt_spec_function): New.
* toplev.c (process_options): Handle flag_gtoggle,
flag_dump_final_insns.
* coverage.c (coverage_begin_output): Don't overwrite .gcno file
during -fcompare-debug-second compilation.
gcc/cp/ChangeLog:
* repo.c (get_base_filename): Use aux_base_name rather than
alternate temporary file during second compare debug compilation.
(finish_repo): Skip during -fcompare-debug-second.
gcc/ada/ChangeLog:
* lib-writ.adb (flag_compare_debug): Import.
(Write_ALI): Skip during -fcompare-debug-second.
gcc/fortran/ChangeLog:
* options.c (gfc_post_options): Disable dump_parse_tree
during -fcompare-debug-second.
gcc/objc/ChangeLog:
* objc-act.c (objc_init): Skip print_struct_values during
-fcompare-debug-second.

From-SVN: r148271

1 files changed, 58 insertions, 1 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index c669c21..99aa2ca 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -302,13 +302,15 @@ Objective-C and Objective-C++ Dialects}.
 -fdump-tree-vrp@r{[}-@var{n}@r{]} @gol
 -ftree-vectorizer-verbose=@var{n} @gol
 -fdump-tree-storeccp@r{[}-@var{n}@r{]} @gol
+-fdump-final-insns=@var{file} @gol
+-fcompare-debug@r{[}=@var{opts}@r{]}  -fcompare-debug-second @gol
 -feliminate-dwarf2-dups -feliminate-unused-debug-types @gol
 -feliminate-unused-debug-symbols -femit-class-debug-always @gol
 -fmem-report -fpre-ipa-mem-report -fpost-ipa-mem-report -fprofile-arcs @gol
 -frandom-seed=@var{string} -fsched-verbose=@var{n} @gol
 -fsel-sched-verbose -fsel-sched-dump-cfg -fsel-sched-pipelining-verbose @gol
 -ftest-coverage  -ftime-report -fvar-tracking @gol
--g  -g@var{level}  -gcoff -gdwarf-2 @gol
+-g  -g@var{level}  -gtoggle  -gcoff  -gdwarf-2 @gol
 -ggdb  -gstabs  -gstabs+  -gvms  -gxcoff  -gxcoff+ @gol
 -fno-merge-debug-strings -fno-dwarf2-cfi-asm @gol
 -fdebug-prefix-map=@var{old}=@var{new} @gol
@@ -4384,6 +4386,61 @@ debug format is long obsolete, but the option cannot be changed now.
 Instead use an additional @option{-g@var{level}} option to change the
 debug level for DWARF2.
 
+@item -gtoggle
+@opindex gtoggle
+Turn off generation of debug info, if leaving out this option would have
+generated it, or turn it on at level 2 otherwise.  The position of this
+argument in the command line does not matter, it takes effect after all
+other options are processed, and it does so only once, no matter how
+many times it is given.  This is mainly intended to be used with
+@option{-fcompare-debug}.
+
+@item -fdump-final-insns=@var{file}
+@opindex fdump-final-insns=
+Dump the final internal representation (RTL) to @var{file}.
+
+@item -fcompare-debug@r{[}=@var{opts}@r{]}
+@opindex fcompare-debug
+@opindex fno-compare-debug
+If no error occurs during compilation, run the compiler a second time,
+adding @var{opts} and @option{-fcompare-debug-second} to the arguments
+passed to the second compilation.  Dump the final internal
+representation in both compilations, and print an error if they differ.
+
+If the equal sign is omitted, the default @option{-gtoggle} is used.
+
+The environment variable @env{GCC_COMPARE_DEBUG}, if defined, non-empty
+and nonzero, implicitly enables @option{-fcompare-debug}.  If
+@env{GCC_COMPARE_DEBUG} is defined to a string starting with a dash,
+then it is used for @var{opts}, otherwise the default @option{-gtoggle}
+is used.
+
+@option{-fcompare-debug=}, with the equal sign but without @var{opts},
+is equivalent to @option{-fno-compare-debug}, which disables the dumping
+of the final representation and the second compilation, preventing even
+@env{GCC_COMPARE_DEBUG} from taking effect.
+
+To verify full coverage during @option{-fcompare-debug} testing, set
+@env{GCC_COMPARE_DEBUG} to say @samp{-fcompare-debug-not-overridden},
+which GCC will reject as an invalid option in any actual compilation
+(rather than preprocessing, assembly or linking).  To get just a
+warning, setting @env{GCC_COMPARE_DEBUG} to @samp{-w%n-fcompare-debug
+not overridden} will do.
+
+@item -fcompare-debug-second
+@opindex fcompare-debug-second
+This option is implicitly passed to the compiler for the second
+compilation requested by @option{-fcompare-debug}, along with options to
+silence warnings, and omitting other options that would cause
+side-effect compiler outputs to files or to the standard output.  Dump
+files and preserved temporary files are renamed so as to contain the
+@code{.gk} additional extension during the second compilation, to avoid
+overwriting those generated by the first.
+
+When this option is passed to the compiler driver, it causes the
+@emph{first} compilation to be skipped, which makes it useful for little
+other than debugging the compiler proper.
+
 @item -feliminate-dwarf2-dups
 @opindex feliminate-dwarf2-dups
 Compress DWARF2 debugging information by eliminating duplicated